Update of analysis of technical run data

Update of analysis of technical run data

T. Spadaro

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Done in the past:- block by block time resolution- T0 correction per column of blocks- muon clustering algorithm- first studies of time correlation with other detectors

Update:- absolute time-zero correction block by block- Novel time reconstruction for LAV, analysis of hit topologies- Analysis of time distributions and LAV-CHOD correlation

To do:- efficiency studies for photons

Outline: done and to do

7/06/2013Update of analysis of Tech. run data - CERN - NA62 PVeto WG

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Data of run 390:- 1 CHOD

candidate and 1 Cedar candidate in time

- 1 cluster on LKr in time + 1 additional LKr cluster close in space with CHOD hit

- Occupancy of few %

Study of hit categories on data


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Data of run 390:- 1 CHOD candidate

and 1 Cedar candidate in time


- Event selection aiming at enriching LAV content

Analyze TDC hit pairs for Low and High threshold of the same physical channel



Hit status definition:1: Tr-Tr 4: Le-Tr2: Tr-Le 5: Le (only hit)3: Le-Le 6: Tr (only hit)

status High

status Low

Station 1

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Data of run 390:- 1 CHOD candidate

and 1 Cedar candidate in time


- Event selection aiming at enriching LAV content

Analyze TDC hit pairs for Low and High threshold of the same physical channel




status High

status Low

Station 2

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Correlate leading hit times

Time correlation vs category: complete hits



status High

status Low

Station 1

dTleading(High-Low) (ns)

?

Odd structure at negative and positive times, check if there are other hits for that channel in the same event

Plot dT vs NToT(Low)

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Check edge population for complete hits


status HighStation 1


status Low

1 2 3 4 1 2 3 4 1 2 3 4NToT (Low) NToT (Low) NToT (Low)

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Leading-leading category



status High

status Low

Station 1


Both trailing edges lost due to HPTDC 5-ns dead time?

Is there a contribution from the 3-time-slot acquisition window? Plot dT vs T(DAQ,Low)

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Check DAQ effect for leading-leading category


status High

status Low

Station 1

TCedar – Tleading(High) (ns)

TCedar – Tleading(High) (ns)

“physics” peak

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Check DAQ effect for leading-leading category


status High

status Low

Station 1

Tleading(High) (ns)

TCedar (ns)

TCedar (ns)

Tleading(High) (ns)Tleading(High) (ns)

CompleteLeading-leading

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Leading-leading time correlation



status High

status Low

Station 1


High-threshold trailing lost, due to HPTDC 5-ns dead time?

If so, ToT of Low threshold should be smaller than that for complete hits: Plot vs ToT(Low)

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High threshold trailing missing



High-threshold trailing lost, due to HPTDC 5-ns dead time?If so, ToT of Low threshold should be smaller than that for complete hits

ToT(Low) (ns)


ToT(Low) (ns)

True, but not always, maybe a DAQ effect is present, too?Check it by plotting also vs Tleading high

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status High

status Low

Station 1


Low-threshold trailing lost, due to DAQ window?

Plot dT vs Trail(DAQ, High)

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status High

status Low

Station 1

dTtrailing(High-Low) (ns)

Where are both leading times?

Plot vs T(DAQ,Low)Plot vs NToTPlot vs NHit/event

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Trailing-trailing time correlation


status High

status Low

Station 1

TCedar – Ttrailing(High) (ns)

TCedar – Ttrailing(Low) (ns)

“physics” peak

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status High

status Low

Station 1

dTtrailing(High-Low) (ns)

High-threshold leading lost...... configuration of low threshold is strange (Tr-Le)

Check vs NToT(Low)Check vs T(DAQ,Tr, High)

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status High

status Low

Station 1

dT(trailing High- leading Low) (ns)

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Run 392 (muon run), merged thanks to Giuseppe including LKr info

minimal request: 1 CHOD candidate

Use muon run for time calibration: rescale all of the LAV times by subtracting the LAV-CHOD time difference

Use High-threshold hits, global time resolution < 1 ns

Time calibration from muon run


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Use Low-threshold hits, since there is no slewing correction:

non-zero offset, ~ -3 ns (compatible with expectation: ~ Trise/2)

resolution worse, ~ 2ns

Time calibration from muon run


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CHOD population comparing muon and kaon run

Check LAV-CHOD correlation


muon run

kaon run

YCH

OD

(cm

)

XCHOD (cm)

XCHOD (cm)

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Check CHOD-LAV alignment, muon run


DT (ns)

Df (rad)

Check time and position correlation with respect to CHOD, Hi-thr

a second peak 25-ns away, time-correlatedmuon run

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Select main time peak, plot a.u. ratio N(CHOD&LAV)/N(CHOD)

Check LAV-CHOD correlation


muon run

YCH

OD

(cm

)

XCHOD (cm)

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Compare muon and kaon run


Check time and f correlation with respect to CHOD, low-threshold

second peak ~40 ns away from the main peakmuon run

kaon run

Df (rad)

Df (rad)

DT

CH

OD

-LAV(n

s)

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Second peak enhanced in the kaon run and for the low threshold

kaon run

muon run

TLAV (ns)

TLAV (ns)

DT

CH

OD

-LAV(n

s)

low threshold

low threshold

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Second peak enhanced in the kaon run and for the low threshold

kaon run

muon run

DTCHOD-LAV(ns)

low threshold

high threshold

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Second peak related to real muons: reflection of a physics signal

muon run

DfLAV-LAV(mrad)

high threshold

DT

LAV-L

AV

(ns)

2 hits in station 1 1 hit in station 1,1 hit in station 2

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Second peak appearance is channel dependent: check high threshold

muon run

Electronic channel of low threshold

DTCHOD-LAV (ns)

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Second peak appearance is channel dependent: check low threshold

muon run

Electronic channel of low threshold

low thresholdDTCHOD-LAV (ns)

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Conclusions and to-do


Absolute time-zero correction block by block satisfactory- resolution < 1 ns on the entire LAV station

A secondary channel-dependent reflection peak biased the time alignment:

- maximum of event occupancy met when (part of) main peak and all of the secondary peak are sampled in the 75-ns DAQ window

- main peak is partly cut expect an effect on efficiency- effect of DAQ window has an impact on hit topologies

LAV-CHOD correlation studied in muon runs- Second peak related to real muons: reflection of a physics signal- geometrical correlation to be validated with MC

Final validation of LAV capability after optimization of HW setup will be done:

- muon runs, using specific channels completely contained in the DAQ window

- kaon runs, using photons (on going)

Update of analysis of technical run data

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