Purpose of the Experiment

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The P152 Experiment at NIRSOverview

1st Workshop of the Italy-Japan Collaborationon Geant4 Medical Application

8-9 March 2004INFN Genova

Katsuya Amako

KEK

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Purpose of the Experiment

To study nuclear interaction processes of medical heavy ion beam with elements of human body (Water, C, N, Ca, P) by the high spatial resolution emulsion chamber.

For reconstruction of tracks recorded in emulsion, the high-speed automatic film scanning machine is utilized.

To study nuclear interaction processes which are important to the shielding of detectors installed in space-craft/satellite.

Compare the obtained experiment results to the Geant4 simulation and to improve Geant4 physics if necessary.

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Why Emulsion Chamber?

Harp Experiment ps214@CERN

Wide acceptance measurement of hadron producitons from interactions of Proton （ 2GeV ～15GeV ） with nucleus 　

• TPC• Forward spectormeter• Gas Cherenkov• 　 ToF, etc

P152 Experiment

I know this comparison is not fare but….

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The P152 Experiment Group History

Nov. 2002 ： The 1st Kickoff Workshop @NIRS Dec. 2002 ： Submitted a proposal to NIRS Jan. 2003: Proposal approved 4 data takings since April 2003

Members（ NIRS ） N. Kanematsu, M. Komori

（ Nagoya ） K. Niwa, T.Toshito, T.Nakamura, T.Ban, N.Naganawa, S.Takahashi

（ Uchu-ken ） M.Ozaki （ Kobe ） S. Aoki (Aichi) Y.Kodama

(Naruto) H.Yoshida (Ritsumei) S.Tanaka (SLAC) M. Asai, T. Koi

(Tokyo) N.Kokubu (Gunma) K. Yusa

(Toho) H.Shibuya, R.Ogawa, A. Shibazaki, T.Fukushima

(KEK) K. Amako, K.Murakami, T. Sasaki

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HIMAC Overview

Experiment Areas

RFQ Linac800 KeV/u

Alvarez Linac6 MeV/u

Synchrotron800 MeV/u

Ion BeamsHe, N, C, O, Ne, Si, Ar, etc

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ECC and Emulsion Film ECC (Emulsion Cloud Chamber) Emulsion Film

(Standard: Opera Film)

Films are stacked to form ECC

[example]

ECC used in the 1st beam time has 116 films.

[Note]

ECC shown here is not one used in the 1st beam time.

12.5 cm

10 cm

Thickness 288

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Opera Film Structure (Cross section view)

Emulsion Layer (Sensitive area)

Emulsion Layer (Sensitive area)

TAC – Film Base(not sensitive)

200 m 44 m44 m

Particle path

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Auto Scanning Machine ( Nagoya Univ.)

films Head of scanning machine (microscope + CCD)

Scanning Speed~7 hours /1 film (both film sides, ~20,000 tracks)

Spatial Resolution~ 1 m

Angular Resolution~ 1 mrad

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Track Reconstruction

Beam Track Reconstruction135 MeV/u 12C beam

Film# 100

Film# 65

2 cm

2 cm

Total track# ~ 20,000

[Note]Each film layer is colored in the　cyclic sequence of

violet,indigo,blue,green,yellow,orange,red

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Particle ID Particle can be identified by the grain density of track

(ionization density)

Z=6

Z=1Z=2

Z=2

Z=1

Z>2

Z=2Z=1MIP

Prelimiary

ionization/grain density

~300

Need some improvement to separate particles with z>2.

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Machine Time Summary April 2003

Goal: Preliminary test to reconstruct ion interactions in ECC Beam: 12C, 135 MeV/u Target ： ECC only

June 2003 Goal: Preliminary test of particle ID using ECC Beam: 12C, 180 MeV/u Target ： ECC only Permanent magnet spectrormeter for particle ID

Sepember 2003 Goal: Preliminary test to measure interactions of 12C with water Beam: 12C, 430 MeV/u Target ： water

January 2004 Goal: 2nd Preliminary test to measure interactions of 12C with water Beam: 12C, 430 MeV/u Target ： water

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Geant4 Simulation

ECC

Beam Line Elements

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Range Struggling of 12C in ECC and Geant4

Point with error bars

data from June 2003 machine time

Solid lineGeant4 5.0 with

standard physics list

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Plan and Subjects of 2004

Establish technology to identify ions from Z=1 to Z=6

This is the major subjects of this year

Establish technology to determine energy/momentum of ions by

measuring multiple scattering and range

Continue data taking of 12C – water interactions

Continue to compare data with Geant4