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AGATA Performance C ommissioning @ PRESPEC. AGATA Commissioning WG. Demonstrate the performance of AGATA in a RIB facility at relativistic beam energies .
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AGATA Performance Commissioning@ PRESPEC AGATA Commissioning WG
Demonstratethe performance of AGATA in a RIB facility at relativisticbeamenergies. Experimentally determine typicalbackgroundlevels, P/N-ratios and detectionsensitivityforCoulex and fragmentationexperiments. Optimisebackgroundconditionsiffeasible. Obtainfirst data-set fortheoptimisation of Pulse-ShapeAnalysis and Gamma-Ray Tracking algorithms(new conditions at the GSI environment). Aim of the AGATA performance commissioning
FRS Introduction AGATA@GSI-FRS 2. LYCCA 3. AGATA
RelativisticCoulomb Excitation Au, Pb Target 250-500 mg/cm2 FRS: RIB RIB: LYCCA Twocommontechniques @ FRS (Z,A) (Z,A) (Z,A)* • Secondaryfragmentationorparticleknockout Be Target 250-500 mg/cm2 FRS: RIB RIB: LYCCA (Z,A) (Z,A-2) (Z,A-2)*
AGATA S2' @ GSI: efficiency vs. # triple (double) clusters EFFICIENCY RESOLUTION • “Reference physics case”: Eg,o = 1 MeV, recoil nucleus at b = 0.43 (E = 100 MeV/u), Mg = 1 (GEANT4 AGATA code from NIMA 621 (2010) 331-343, E.Farnea et al.)
RelativisticCoulomb Excitation Au, Pb Target 250-500 mg/cm2 FRS: RIB RIB: LYCCA Twocommontechniques @ FRS (Z,A) (Z,A) (Z,A)* • Secondaryfragmentationorparticleknockout Be Target 250-500 mg/cm2 FRS: RIB RIB: LYCCA (Z,A) (Z,A-2) (Z,A-2)*
Relativistic Coulomb Excitation Au, Pb Target 250-500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Twocommontechniques @ FRS (Z,A) (Z,A) (Z,A)* 300 MeV/u 100 MeV/u • Secondaryfragmentationorparticleknockout Be Target 250-500 mg/cm2 Bremsstrahlungsbackground FRS: RIB RIB: LYCCA (Z,A) (Z,A-2) (Z,A-2)*
Relativistic Coulomb Excitation Au, Pb Target 250-500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Twocommontechniques @ FRS (Z,A) (Z,A) (Z,A)* 300 MeV/u 100 MeV/u Counts Smoothbackground Eg
Effect of the lead absorber No shielding 2mm Pb shielding Really needed? how thick? Test it ! 10+5 5+5 0+5
Relativistic Coulomb Excitation (justanexample) Energy Degrader Au Target 500 mg/cm2 FRS: RIB RIB: LYCCA Coulexbenchmark case 54Cr 54Cr 54Cr* 300 MeV/u 100 MeV/u 104particles/spill pg-rate@AGATA = I54xNatxsCoulexxeg 2+ 839.9 keV, 7.9 ps, B(E2) = 14.6 W.u. 0+ 54Cr
Relativistic Coulomb Excitation Au Target 500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Coulexbenchmark case 54Cr 54Cr 54Cr* 300 MeV/u 100 MeV/u 104particles/spill pg-rate@AGATA = I54xNatxsCoulexxeg 2+ 839.9 keV, 7.9 ps, B(E2) = 14.6 W.u. 0+ 716 C/hour 54Cr
Relativistic Coulomb Excitation Au Target 500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Coulexbenchmark case 54Cr 54Cr 54Cr* 300 MeV/u 100 MeV/u 104particles/spill pg-rate@AGATA = I54xNatxsCoulexxeg RAW 2+ 839.9 keV, 7.9 ps, B(E2) = 14.6 W.u. 0+ 716 C/hour 54Cr
Relativistic Coulomb Excitation Highefficiencyconfiguration (d = 8.5 cm) Au Target 500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Coulexbenchmark case 54Cr 54Cr 54Cr* 300 MeV/u 100 MeV/u 104particles/spill pg-rate@AGATA = I54xNatxsCoulexxeg RAW 2+ 839.9 keV, 7.9 ps, B(E2) = 14.6 W.u. 0+ 716 C/hour 54Cr
Relativistic Coulomb Excitation Highefficiencyconfiguration (d = 8.5 cm) Au Target 500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Coulexbenchmark case 54Cr 54Cr 54Cr* 300 MeV/u 130 MeV/u 104particles/s pg-rate@AGATA = I54xNatxsCoulexxeg AGATA Simulation 2+ RISING Exp. 839.9 keV, 7.9 ps, B(E2) = 14.6 W.u. 0+ 54Cr PhD A. Buerger
Up to A<90 (tokeepgood A resolution in LYCCA) • Eg in typicalCoulex/Fragmentationenergyrangei.e. 400keV-1.5 MeV • Large B(E2) in ordertooptimisebeam-time • Lifetime of thelevelabove 4 ps (todecayafterthe target) • Stablebeam (tofacilitate FRS start-up, etc) Beamcandidates (fromnndcdatabase) s ~ B(E2h)xZ2
Simultaneous Coulomb excitation of the Au-target atoms online inspection of the ARRAY performance (notDopplershifted). Concomitantaspects • Ensure (online, butaftersomehoursduetothelowyield) thatparticle-gamma coincidences are workingproperly. • Allowsto determine Peak/Total-ratio and backgroundlevelforthe RAW spectrum, althoughtheseparameters are actuallyrelevant in theDopplerCorrectedspectrum.
Simultaneous Coulomb excitation of the Au-target atoms online inspection of the ARRAY performance (notDopplershifted). • Secondaryfragmentationreactions in Au-target same P/N-studyforfragmentationreactions, e.g.54Cr 50,52Cr, 50,52V, etc. Concomitantaspects • Secondaryfragmentationorparticleknockout Au Target 500 mg/cm2 FRS: RIB RIB: LYCCA (Z,A) (Z,A-2) (Z,A-2)*
Au Target 500 mg/cm2 Energy Degrader FRS: RIB RIB: LYCCA Countingratessummary (example) 54Cr 54Cr 54Cr* 300 MeV/u 100 MeV/u 104particles/spill Beam time request: about 1 weektocollectenoughstatistics in everycrystal, and haveenough data to test PSA and tracking algorithms.
The plan istoperforman “easy” Coulomb excitationexperiment in orderto determine experimentallythedetectionsensitivity of the AGATA arrayunder real experimental conditions at GSI, as well as Peak/Noise ratio in the gamma-rayenergyrangearound 1 MeV. Thestatistics/crystalshouldbelargeenoughtooptimise and tostudythe performance of PSA and Tracking algorithms. • Thisbenchmark-measurementwillbeperformed at thetwo “extreme” configurations of high-resolution (d=23.5cm) and high-efficiency (d=8.5cm). Twolongruns. • Simultaneouslyweshouldbeabletosee Coulomb excitationfromtheGold target (no Doppler-shift), whichallowsonetoconfirm online thatparticle-gamma correlationsare madeproperly. • At thesame time, selectingknockoutchannelsvia LYCCA we can studyalsotheseaspectsforsecondaryfragmentationexperiments. • Further ideas are welcome. Summary
11000 7000 3000 1850 1950 2050 2150 2250 Disentanglement of thebackgroundcomponentsvia BaF2 HECTOR detectors (RISING) Origin of the background radiation determined with HECTOR Target area Pb shield BaF2 (HECTOR) projectile –gtime 10 ns FRS area T • downstream radiation • target radiation • neutrons • upstream-beam stopper radiation
11000 7000 3000 1850 1950 2050 2150 2250 Disentanglement of thebackgroundcomponentsvia BaF2 HECTOR detectors (PRESPEC) HECTOR • Relativistic Coulomb Excitation Energy Degrader Au Target 500 mg/cm2 FRS: RIB RIB: LYCCA 54Cr 54Cr 54Cr* 300 MeV/u 130 MeV/u 104particles/s BaF2 (HECTOR) projectile –gtime ? • downstream radiation • target radiation • neutrons • upstream-beam stopper radiation 10 ns T • Proper time-gatefor gamma-rayspectrum in • AGATA (?)
LYCCA A and Z ID around100Sn Slidefrom LYCCA Collaboration
AGATA S2' @ GSI: efficiency vs. # triple (double) clusters • “Reference physics case”: Eg,o = 1 MeV, recoil nucleus at b = 0.43 (E = 100 MeV/u), Mg = 1 (GEANT4 AGATA code from NIMA 621 (2010) 331-343, E.Farnea et al.)