Analysis report4. 13th. Friday 2007.

H.Yim

To apply efficiency correction on the data spectrum, DEMONS code is investigated and modified.

Kinetic energy vs. Energy Loss(Before ADC conversion)

Kine

tic e

nerg

y [M

eV]

Energy Loss [MeV]

Kine

tic e

nerg

y [M

eV]

Energy Loss [MeV]

Kine

tic e

nerg

y [M

eV]

Overlaid

DEMONS GEANT

Energy Loss [MeV]

E-loss distribution is same with GEANT.

Then, response function is ?

Modified DEMONSOriginal response function Birk’s saturaion function

Kine

tic E

nerg

y [M

eV]

ADC [MeVee]

Kine

tic E

nerg

y [M

eV]

Overlaid with GEANT result

DEMONS

ADC [MeVee]

Birk’s saturation function is successfully implemented in DEMONS code.

Measurement of Birk’s parameter

C1=0.00757

Birk’s saturation function

Original parameter

Measured parameter

~67 ~60.3

ADC[MeVee]ADC[MeVee]

Kine

tic E

[MeV

]

ADC[MeVee] ADC[MeVee]

Kine

tic E

[MeV

] DATA (E549) GEANT

Applying measured Birk’s parameters to simulations

GEANT with new Birk’s paraDEMONS with new Birk’s para

Kine

tic E

nerg

y [M

eV]

ADC [MeVee]

Kine

tic E

nerg

y [M

eV]

ADC [MeVee]

Kine

tic E

nerg

y [M

eV]

ADC [MeVee]

Overlaid

Now, DEMONS and GEANT shows same performance.

(at least, about proton simulation)

Data(E549) & GEANT

Kine

tic e

nerg

y [M

eV]

ADC [MeVee]

Kine

tic e

nerg

y [M

eV]

ADC [MeVee]

Kine

tic e

nerg

y [M

eV]

Overlaid

DEMONS GEANT with new Birk’s para

ADC [MeVee]

Neutron spectrum comparison

ADC [MeVee]ADC [MeVee]

1/

beta

1/

beta

Modified DEMONS Data (E549)

1/beta vs. ADC 1/beta vs. ADC

Now, stripe pattern is well agree.

Neutron efficiency

Momentum MeV/c

Dete

ctio

n e

ffici

ency

10 MeVee

15 MeVee

7 MeVee

5 MeVee

3 MeVee

0 MeVee

20 MeVee

Threshold

Background subtracted spectrum

Semi-inclusive [Line] and background [Point]

Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c]

Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c]

Background subtracted neutron spectra

5 MeVee 7 MeVee 10 MeVee 15 MeVee 20 MeVee

5 MeVee 7 MeVee 10 MeVee 15 MeVee 20 MeVee

Efficiency corrected spectra

Efficiency corrected

Background subtracted

Semi-inclusive

Momentum [MeV/c] Momentum [MeV/c] Momentum [MeV/c]

Summary

• Response function of DEMONS code is modified to make agreement with data.

• Efficiency corrected neutron spectra were obtained.