AGATA at GSI and FAIR

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1 AGATA at GSI and FAIR J. Gerl GSI Darmstadt, Germany NUSPIN + AGATA Venice, Italy July 1, 2016

2 PRESPEC-AGATA Physics Campaign Physics workshop in Istanbul 34 LOIs, 12 proposals initially proposed, 9 accepted by GSI PAC in ,212 Pb 202 Pt protons Sr 80 Zr isospin triplets A=46, 62, Cr, 52 Fe Mg Pd Cd Sn Fe 54, Cr Sc 48 Ar Br neutrons N=50 70,72 Zn 68,74 Ni Mo Zr Te Cd Pd 132 Sn, 131 In Os, W, Evolution of collectivity near 208 Pb Shell structure near 78 Ni, 100 Sn, 132 Sn Development of nuclear collectivity Shell evolution in light nuclei Nuclear structure at the N=Z line M1, E1, E2, E3 strength Physics workshop TU-Darmstadt 15 new LOIs 22 2

3 45 3 Approved proposals and runs in 2012 and 2014 S424: Korten/Gerl Performance commissioning (PRESPEC-AGATA) S429: Rudolph / Podolyák / Gerl Quadrantic evolution of collectivity around 208 Pb S430: Wieland / Gorská Pygmy Dipole Resonance in 64 Fe and the properties of neutron skin S426: Pietralla / Rainovski / Gerl Relativistic M1-Coulomb excitation of 85 Br S433: Gadea / Gorská S428: Pietri Coulomb excitation of the band-terminating 12 + yrast trap in 52 Fe Shape evolution in neutron-rich Zr S434: Recchia / Bentley talk by Damian Ralet Transition rates and mirror energy differences in isobaric multiplets Campaign suffered from severe beam time cuts (imposed by BMBF) and unexpected beam intensity problems in 2014 talk by Tayfun Huyuk talk by Alberto Boso

4 Relativistic Coulomb excitation / fragmentation 112 Sn Au Coulomb interaction excited nucleus Prefragment Equilibrated nucleus

5 Atomic Background Radiation Bremsstrahlung Radiative electron capture (REC) capture of target electrons into bound states of the projectile: Impossibile visualizzare l'immagine. Primary Bremsstrahlung (PB) capture of target electrons into continuum states of the projectile: Impossibile visualizzare l'immagine. Secondary Bremsstrahlung (SB) Stopping of high energy electrons Impossibile visualizzare l'immagine. in the target: High granularity γ detector 22 5

6 Doppler Effect Doppler shift Doppler broadening position sensitive γ detector 22 6

7 22 7 In-beam Spectroscopy production selection identification reaction spectroscopy identification γ detectors Calorimeter

8 AGATA at GSI set-up AGATA Challenge: S2 Geometry FRS beam size!!! 10 triple Cluster + 5 double Cluster + = S2' Geometry: P ph 17%; E = 0.4 % ( sensitivity gain 30x RISING) 22 8

9 AGATA detector layout Status X ADC02 ADC03 ADC01 9

10 45 10 FRS S4 set-up and LYCCA FRS 2 MUSIC Ionization detectors for energy loss 2 plastic detectors for ToF (one of it segm. Finger det.) 2 TPC for position LYCCA 17 silicon DSSSD detectors for tracking and energy loss 144 CsI scintillators for particle energy 3 fast plastic scintillators for time of flight and tracking

11 The Set-up in Reality LYCCA AGATA Hector AGATA Tracking array 3x2+6x3 crystals R = cm ε Ph = 4-7% E = % 22 11

12 45 12 Complex data analysis AGATA NARVAL acquisition Preamplifier traces (on disk) Experiment (simplified) FRS/LYCCA/HECTOR MBS acquisition Raw Data (on disk) Pulse shape analysis Interaction Points (on disk) Analysis (simplified) Make sure everything is correct Lots of parameters to understand / optimize Particle tracking and identification Gamma-Ray tracking and Doppler correction Gamma Spectrum

13 Coarse Spill Structure at FRS S4 hits /100µs 3 s spill 23 khz Coarse spikes with up to 100x hits compared to the mean value per 100 us interval. Voids with up to 50% empty time intervals. multiplicity /100µs mean 2.9 DAQ processing time: 100µs Only 1 hit /100µs contributes. Spikyness reduces data acceptance by up to a facotor of 3!!!!

14 Fine Spill Structure at FRS S4 Fine spikes with up to 50x instantaneous rate compared to mean rate. Severe overloading of particle tracking detectors!!!! Reduced detection efficiency and reduced resolution!!!! 14 GSI accelerator WG initiated to solve the problem 24

15 Particle-AGATA correlation Scattering of 183 AMeV 238 U on a 0.4g/cm 2 Au target foil: no Doppler correction Au cos θ γ Au K α Au K α Au K α Au K β Au K β Au K β Michael Reese

16 Particle-AGATA correlation Scattering of 183 AMeV 238 U on a 0.4g/cm 2 Au target foil: Doppler corrected U E γ 0 = E γ 1 β cosϑγ 2 1 β ab cos θ γ U K α U K α U K α U K β U K β U K β Michael Reese

17 AGATA Efficiency versus P/T 60 Co at nominal position Natasa Lalovic et al

18 Triple DSAM at relativistic energies A=46 multiplet Only possible with ultra-high position resolution of AGATA Mike Bentley et al

19 Lifetimes from decay position Triaxiality in heavy Mo isotopes θ θ θ >θ Only possible with relativistic beams Damian Ralet 22 19

20 Relativistic Coulomb excitation 206 Hg Collectivity around 208 Pb 1068 Pt to Po; A = Referenz: 206 Pb preliminary Tom Alexander Shell model predicts: 0.18 e 2 b

21 Was a Great Collaboration 22 21

22 22 22 FAIR...what gives us confidence 2015 Heuer report confirms excellent science case of FAIR experiments FAIR Council agrees to cover additional construction costs, requests LEB building to be included in MSV and demands new management 2016 GSI/FAIR organisation and management completely changed GSI and FAIR are factually merged and work coherently together New FSB director introduces staged construction along the beam line New technical managing director sets up new project structure dividing FAIR into five machine and four experiment sub-projects Project lead team gets full responsibility for sub-projects LEB building planning caught up time delays and is on schedule Phase 0 experimental programme with FAIR injectors at GSI confirmed for 2018 and the following years until the FAIR facility is operational Based on integrated FAIR time plan first beams will be available in 2022 FAIR (MSV) will be completed in all aspects by 2025

23 FAIR Timeline

24 NUSTAR time line Super-FRS construction and installation commissioning operation NUSTAR caves civil construction NUSTAR experiments construction and operation outside FAIR AGATA at HISPEC installation commissioning operation at FAIR 24

25 HISPEC at the LEB LYCCA wall β, α, isomer tagging

26 22 26 HISPEC-AGATA at FAIR Phase 1 > 100x RIB intensities Flat spill structure 60 AGATA Ge crystals >20% Efficiency Easier control and analysis

27 Conclusions The PRESPEC-AGATA campaign at GSI in could run only a limited experimental programme Data analysis is very complex and time consuming Novel experimental methods emerge from the combination of relativistic beams and AGATA First physics results are popping up The FAIR project is developing well after a re-launch in An experiment campaign with AGATA is envisaged for FAIR Phase 1 in the early 20s. Combining 40 AGATA detectors with strong exotic isotope beams will lead to exciting physics opportunities