Objectives Determine Detector offsets in hall B

reference frame and thus absolute beam position at Hycal

Examine Flux calculation and see if beam trips can be eliminated more effectively by changing parameters within existing software

Beam PositionMathew Reece amp Dustin Woolford

Beam Position Ideally to find the absolute beam position two

BPMs can be used and then offsets determined from the projection of that line to other detectors

However there is a magnetic field present between the two BPMs in hall B Is it negligible

There is a single run (4943) where the beam position is known to change abruptly midway through the run at BPM1 and at Hycal but very little at BPM2

Whats known BPM data suggests that readouts are in the

hall B frame HYCAL x = 002 mm beam right y = 009

mm high relative to CLAS center line Gamma Profiler needs to be determined

Linearity By using only data from (4349)

the unknown detector offsets do not affect the calculations

We assume that the beam is linear between the BPMs and compare every other event in the run with the first event

The angles are determined by the arctangent of the difference between the measured points on a detector for the first event and a later event divided by the distance between that detector and BPM 2 As shown on the previous slide α1 is for BPM 1 and α2 is for the γ profiler

By our conventions the ratio α2α1 will be -1 if the beam is linear [since arctan x = -arctan (-x)]

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Beam PositionMathew Reece amp Dustin Woolford

Beam Position Ideally to find the absolute beam position two

BPMs can be used and then offsets determined from the projection of that line to other detectors

However there is a magnetic field present between the two BPMs in hall B Is it negligible

There is a single run (4943) where the beam position is known to change abruptly midway through the run at BPM1 and at Hycal but very little at BPM2

Whats known BPM data suggests that readouts are in the

hall B frame HYCAL x = 002 mm beam right y = 009

mm high relative to CLAS center line Gamma Profiler needs to be determined

Linearity By using only data from (4349)

the unknown detector offsets do not affect the calculations

We assume that the beam is linear between the BPMs and compare every other event in the run with the first event

The angles are determined by the arctangent of the difference between the measured points on a detector for the first event and a later event divided by the distance between that detector and BPM 2 As shown on the previous slide α1 is for BPM 1 and α2 is for the γ profiler

By our conventions the ratio α2α1 will be -1 if the beam is linear [since arctan x = -arctan (-x)]

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Beam Position Ideally to find the absolute beam position two

BPMs can be used and then offsets determined from the projection of that line to other detectors

However there is a magnetic field present between the two BPMs in hall B Is it negligible

There is a single run (4943) where the beam position is known to change abruptly midway through the run at BPM1 and at Hycal but very little at BPM2

Whats known BPM data suggests that readouts are in the

hall B frame HYCAL x = 002 mm beam right y = 009

mm high relative to CLAS center line Gamma Profiler needs to be determined

Linearity By using only data from (4349)

the unknown detector offsets do not affect the calculations

We assume that the beam is linear between the BPMs and compare every other event in the run with the first event

The angles are determined by the arctangent of the difference between the measured points on a detector for the first event and a later event divided by the distance between that detector and BPM 2 As shown on the previous slide α1 is for BPM 1 and α2 is for the γ profiler

By our conventions the ratio α2α1 will be -1 if the beam is linear [since arctan x = -arctan (-x)]

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Whats known BPM data suggests that readouts are in the

hall B frame HYCAL x = 002 mm beam right y = 009

mm high relative to CLAS center line Gamma Profiler needs to be determined

Linearity By using only data from (4349)

the unknown detector offsets do not affect the calculations

We assume that the beam is linear between the BPMs and compare every other event in the run with the first event

The angles are determined by the arctangent of the difference between the measured points on a detector for the first event and a later event divided by the distance between that detector and BPM 2 As shown on the previous slide α1 is for BPM 1 and α2 is for the γ profiler

By our conventions the ratio α2α1 will be -1 if the beam is linear [since arctan x = -arctan (-x)]

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Linearity By using only data from (4349)

the unknown detector offsets do not affect the calculations

We assume that the beam is linear between the BPMs and compare every other event in the run with the first event

The angles are determined by the arctangent of the difference between the measured points on a detector for the first event and a later event divided by the distance between that detector and BPM 2 As shown on the previous slide α1 is for BPM 1 and α2 is for the γ profiler

By our conventions the ratio α2α1 will be -1 if the beam is linear [since arctan x = -arctan (-x)]

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Important note It is important to verify

that the beam position on BPM 2 does not vary significantly in order for this method to be valid As the graph shows the location where the beam passes through BPM 2 does not move more than 02 mm during the run

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Now that the constancy of BPM 2 has been verified let us look at the α2α1 ratio

Ratio of Change in Beam Angles for run 4349

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0 60000 120000 180000 240000 300000

Event

Ra

tio

Ratio

Ideal Ratio

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Determining offsets A Java program that will use BPM2 and Hycal to

determine (xy) at the gamma profiler is written Average offsets for each run must be determined

and then entered into the MySQL database The same program must be re run for BPM2 and

Gamma Profiler to determine (xy cos(x) cos(y) Yet to be completed

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

LuminosityDustin Woolford

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

General Idea Tagged Yield = Cross Section x target thickness x

solid angle x Nγ tagged (exp) Nγ tagged (exp) = Ne (exp) x Tagging ratio Tagging ratio = Nγ tagged (cal) Ne (cal) Given a Tagged yield target thickness solid angle

and the flux the Pi0 cross section can be extracted

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Flux Nγ tagged (exp)

(Flux) Tagged photons per run per T channel Nγί = Neί x Rί where N and R are the number of electrons per T

channel and the tagging ratio respectively Rί is determined during the TAC runs

Neί = ( ηeί w x ηtrigs) x live 1

- ηeί = e- in a T channel in a given window

- w = size of the TDC window

- ηtrigs = of trigger events

Basically average e- rate for a T channel x live time

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Live Time of DAQ Dead time = Live 1 Live 2 Both Live 1 and Live 2 are driven by a 195316 +-

00045 kHz internal clock Live 1 is gated Live 2 is free TDC start is attached to the tagger and the stop is

initiated by a Pi0 event Trigger is also activated by a Pi0 event in hycal There is a 25 ns internal dead time for the TDC separate

from the trigger dead time Donrsquot need to correct for dead time because only tagged

Pi0 event go to elastic scattering

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Considerations Two types of tagging ratios

1) Absolute ndash uses lead glass solid block and is assumed to have 100 efficiency at low photon intensities (TAC)

- given by Rabs = N γTAC e- Ne-

2) Relative ndash uses the pair spectrometer to monitor the tagging ratio during runs but has 006 efficiency

-given by Rrel = N pse+e- - e- Ne-

Method 1 must be used to calibrate 2

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Considerations contrsquod Effects that may reduce the Absolute tagging ratio

from 1 three primary factors1) photon is produced but absorbed before reaching the TAC ( effect is reduced by helium baghellipbut not corrected for )

2) electron decelerates in the target without producing a photon 3) extra electrons in the tagger (effect gets large at high beam intensities so Rrel must be corrected for )

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Corrections (brief list non-exhaustive) Relative tagging ratio has back ground that

must be accounted for (background = Integral of events w)

Rrel is intensity independent at the at low beam intensity ( 01 ndash 100 nA

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Corrections contrsquod To correct for dependence at high beam intensity the relative

tagging ratio per T counter was averaged for all runs Then for each affected run Rrel was normalized to its corresponding average per T counter

Collimators 86 mm and 127 mm were found to cut 4 and 1 of the beam respectively

Run to run stability ( good up to run 5100) Live time problem ( implemented algorithm to solve )

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Tagger Detector Rate 3 ways ( Integral exponential and Poisson method) Integral is primary means The time distribution is integrated over a range which

excludes the triggering events and depletion from LIFO limits The integral is divided by the product of integration interval and of events over which the distribution was accumulated (Aramrsquos luminosity monitoring Primex notes)

Independent of TDC dead time due to using Live 1 Can be used for high and low rate detectors Tosses a lot of data and abstract coincidence detectors are

affected subtly by the LIFO limit and dead time

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Pflux package Prim_ana has Pflux package that links data analysis with the luminosity Attempts to identify and eliminate beam trips Run is pre-segmented into 5 second intervals Pflux Uses the integral

method to calculate tagging rate and live time for each segment Averages live time for all segments and fits Gaussian to the ldquoavg

histogramrdquo Identifies everything outside 3 σ as a beam trip cuts 2 five second intervals following identified beam trip Configurations

- beam_trip activates beam trip cuts - num_bad of 5 second intervals cut after beam trip- livetime_sigma number of standard deviations that contain ldquogoodrdquo data

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

Live Time Study ( courtesy of Eric Clinton and Aram Teymurazyan)

Uses Pflux package to output flux per run per T channel per E channel live time and average flux and live time for each run

Standalone from prim_ana Use Root and excel to graph flux as a

function of sigma and of cut intervals

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

flux vs sigma

0

05

1

15

2

25

3

35

0 2 4 6 8

varied sigma

tota

l F

lux

avg

li

ve t

ime

5003

498850505059

4981

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)

fluxlive t vs number of intervals cut

y = -02219x + 29384

y = -00139x + 20943

y = 0011x + 10802

0

05

1

15

2

25

3

0 2 4 6

of intervals cut after identified beam trip

flu

x l

ive

t

4981

5003

4988

Linear (4988)

Linear (5003)

Linear (4981)