24.06.2009

Simulations of the AGATA Response to Relativistic

Heavy Ions Beams

Pavel Detistov

University of Sofia “St Kliment Ohridski”

24.06.2009

The Problem

• Radiative Electron Capture (REC) – K and L shells are considered

• Primary Bremsstrahlung• Secondary Bremsstrahlung

Passage of charged ions through matter involves interaction with material’s atomic shells.

σatomic interactions ~ 10000 times σnuclear

The main processes are defined as:

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Solution

Simulation model is based on GEANT4 toolkit

Creation of new process classes in order to represent different processes:

1.G4ionRadioactiveElectronCaptureK (& L)

2.G4ionPrimaryBremsstrahlung

3. SecondaryBremsstrahlung

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WHAT IS AGATA?

Advanced GAmma-ray Tracking Array

High efficiency 4π detector array

180 detectors grouped in 60 equal triple clusters

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RISING @ GSI

• Array of ex-EUROBALL cluster detectors

Three campaigns: Fast Beam Campaign Stopped Beam CampaigngRising Campaign

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Stopped beam campaign

Rising Stopped beam

Agata Stopped beam

535 keV

535 keV

719 keV

(7-)

( 4+)

( 2+)

0+

280 μs

202Pt

535 keV

535 keV

719 keV

(7-)

( 4+)

( 2+)

0+

280 μs

202Pt

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Rising for 202Pt

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Spectra for 202Pt

0.01

0.1

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En$rgy, k$V

Agata for 202Pt

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En$rgy, k$V

Rising vs Agata

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Fast Beam campaign

Rising Fast Beam Campaign

Agata Fast beam configuration 1

Agata Fast beam configuration 2

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Spectra for 37Ca experiment

37Ca @ 9Be with 195.7 AMeV700 mg/cm2 Be Target

36Ca: 21+ → 0g.s.

+

with E = 3015 keV

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Agata configuration 2 spectra for 37Ca with data

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Agata configuration 1 spectra for 37Ca with data

Data are taken from P.Doornenbal’s thesis @ GSI

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Rising spectra for 37Ca with data

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Conclusions

AGATA benefits from its higher efficiency compared to RISING array

Due to the high multiplicity (~103)of the background tracking algorithms should be able to deal with that!

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Thank you for Thank you for your attentionyour attention!!