A high energy detector for FAIR. Dr. José Sánchez del Río Sáez Universidad Europea de Madrid (UEM) and Instituto Estructura de la Materia (IEM)

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1 A high energy detector for FAIR Dr. José Sánchez del Río Sáez Universidad Europea de Madrid (UEM) and Instituto Estructura de la Materia (IEM)

2 Outline 1.The new facility FAIR 2. The R3B branch: experimental setup 3. Detectors in R3B 4. El experiment S Gamma and protons calorimeter for the new R3B facility 6. The end-cap: phoswich configuration 7. Experimental results in phoswich configuration

3 Outline (II) 8. Montecarlo simulation prgrams 9. Best selction of the optimum length of the crystals in phoswich configuration 10. Photopeak efficiencies for gammas and protons 11. Protons in CEPA: The telescope ΔE vs E 12. Beam tests with protons and gammas 13. Montecarlos simulations results

4 Outline (III) 14. Endcap design for the calorimeter: Different models proposed 15. The R3BRoot program 16. Simulations resultsfor the barrel with R3BRoot 17. Conlussions 18. Future aims

5 The new FAIR

6 The new FAIR

7 FAIR - Facility for Antiproton & Ion Darmstadt Germany FAIR SIS 100/300 UNILAC SIS 18 ESR Rare-Isotope Production Target GSI today HESR Super FRS Antiproton Production Target RESR CR 100 m FLAIR NESR 7

8 The FAIR research community SFRS: Production and separation of exotic nuclei NUSTAR 8

9 NUSTAR a facility for NUclear STructure & Astrophysis Research Supercon ducting Fragment Separator High Energy Reaction Set-up Multi- Storage Rings Energy bunched and stopped beams Low energy and stopped beams Super-FRS Secondary beams produce by fragmentation and fission R 3 B Research with Relativistic Radioactive Beams Olof Tengblad ISNP 2009 MUMBAI 9

10 Super-FRS radioactive beams at FAIR Z Energy (0 1.5 GeV/u) Half-lives ( s - >s) N 8 10

11 The Super-FRS 11

12 NUSTAR > 800 members from 37 countries and 146 institutions Annual NUSTAR Collaboration Meeting 12

13 NuSTAR Experiments Nuclear reactions Relativistic energies R 3 B Cooled beams EXL High-res. spectroscopy HISPEC Decay properties Stopped beams DESPEC Ground state properties Masses MATS, ILIMA Radii, momenta LASPEC New tools Electron RIB scattering ELISe p-bar RIB collider AIC 13

14 The Modularized FAIR start Module 0 SIS100 op. 2015/16 Module 1 SIS100-EXP op. 2015/16 Module 2 SFRS +R3B op Module 3 Antiproton, CR, HESR MODULE DECISION CONSTRUCTION TIME (month) START CONSTRUCTION Olof Tengblad ISNP 2009 MUMBAI Module 0-3 Cost: 1027 M Available: 1039 M OPERATIONAL / / / / / /

15 Central Topics for NuSTAR at FAIR Quest for the limits of existence Halos, Open Quantum Systems, Few Body Correlations Changing shell structure far away from stability Skins, new collective modes, nuclear matter, neutron stars Phases and symmetries of the nuclear many body system Origin of the elements unified theory (ab-initio, density functional, shell model) Neutron Skins Pygmy Resonance Neutron stars Halos Talk: I33. Peter von Neumann-Cosel, Pygmy dipole resonance in stable nuclei 15

16 R 3 B: Reactions with Relativistic Radioactive Beams Kinematically complete measurement of reactions with high-energy secondary beams Nuclear Astrophysics Structure of exotic nuclei Neutron-rich matter A universal fixed-target experiment for complete inversekinematics reactions with relativistic RIBs (~ MeV/u), Experiments with the most exotic (<1 ion/s) and short-lived nuclei - exploring the isospin frontier at and beyond the driplines Concept built on existing ALADIN-LAND experiment at GSI 16

17 How does it work FAIR (Facility for antiproton and ion research) R 3 B p n H R 3 B collaboration: 50 institutes 180 scientists Olof Tengblad ISNP 2009 MUMBAI 17

18 Reaction mechanism: Coulomb dissociation Diffraction Absorption Final state interaction High Energy Reaction Studies setup for kinematical complete measurements Exp. variables: Beam energy 30 MeV 1 GeV/A Target material H Pb Projectile 6 He 238 U Observables: n-momentum distribution Charge fragment momentum Invariant mass Angular correlations Olof Tengblad ISNP 2009 MUMBAI 18

19 Light-Ion Induced Direct Reactions elastic scattering (p,p), (, ), nuclear matter distribution (r), skins, halo structures inelastic scattering (p,p ), (, ), deformation parameters, B(E2) values, transition densities, giant resonances charge exchange reactions (p,n), ( 3 He,t), (d, 2 He), Gamow-Teller strength transfer reactions (p,d), (p,t), (p, 3 He), (d,p), single particle structure, spectroscopic factors spectroscopy beyond the driplines neutron pair correlations neutron (proton) capture cross sections knock-out reactions (p,2p), (p,pn), (p,p 4 He) ground state configurations, nucleon momentum distributions, cluster correlations Olof Tengblad ISNP 2009 MUMBAI 19

20 Poster D2 S. Chakraborty & U.Datta Pramanik et al, Saha Inst of Nuclear Physics, Kolkata, India Olof Tengblad ISNP 2009 MUMBAI 20

21 - Unbound Light Nuclei 21

22 Proton knockout reaction on MeV/u Inverse kinematics Beam: Target: liquid Hydrogen 14 Be (fragmentation of 18 O@304MeV/u) Yu. Aksyutina et al. PLB 666(2008)430 22

23 1 H( 14 Be,2pn) 12 Li Differential cross section as function of relative energy for 12 Li( 11 Li+n) after 1p knockout from 14 Be =1.47(19)MeV 12 Li gs: a virtual s-state with a scattering lenght -13.7(1.6)fm S 2n = 1.26(13) MeV E fn P r r f P M m n f n Yu. Aksyutina et al. PLB 666(2008)430 23

24 1 H( 14 Be, 2p) 13 Li Diferential cross section as function of relative energy from 13Li(11Li+2n) Correlated background E 2 fn 2 2/7 f2 n.2( 21 S2 n Ef 2n ) d de C. Forssén et al. NPA 673 (2008) 143 Yu. Aksyutina et al. PLB 666(2008)430 E r = 1.47(31) MeV three- body resonance 24

25 What do we gain by FAIR Higher Primary beam energy Higher secondary beam intensity Thicker reaction targets In the order of 1 g/cm 2 Implies an extended detection scheme with better efficiency and resolution Reaction products Kinematically forward focused Possible study more exotic nuclei efficient down to 1 ion/s, shorter halflive Olof Tengblad ISNP 2009 MUMBAI 25

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27 Some detectors S2 and S8 scintillators S2 and S8 are scintillators for the time-of-flight (ToF) measurements. The flight time of the particle is measured between S2 or S8 and the POS detector. This information is used together with the energy loss in the PSP detectors for particle identification. The light output at both ends of the scintillators is recorded by two photomultipliers. The time difference of the signals can be used to determine the position of the particle. The thickness of the scintillators can be choosen. Available materials and thicknesses for S2 and S8 and their location can be found at the FRS page. In land02, these detectors are called SCI01 and SCI02 and in the root-tree Sc01 and Sc02.

28 PSP (Stands of position silicon photodiode)

29 POS (position detectors)

30 ROLU

31 Crystal Ball

32 Crystal Ball

33 CSI

34 Silicon Strips Detectors

35 Großer FIberdetektor Position resolution ~ 1mm

36 TFW (Time of flight Wall)

37 LAND (Large Area Neutron Detector) neutrons

38 PDF Drift Chambers

39 DTF (Dick Tof Wand)

40 NTF

41 FAIR (Facility for Antiproton and Ion Research) FAIR(Facilityforantiproton and ion research) ions/s 2-30 GeV/nucleon (0.32 GeV/u) Pillar of Fair: Program centered in the range exotic radioactive beams delivered from the FRS NUSTAR (planned experiments folowing the FRS) R3B project: a fixed Target Experiment that is the sole occupant of the high energy branch R 3 B n H p n NUSTAR (Nuclear STructure, Astrophysics and Reactions) Benefits from the super-frs beams (0.32 GeV/u) with the characteristics inherent to the inflight production method. Many detectors that alows to identify the fragments from the beam delivered by the FRS and determine the momentum before and after the reaction in the target, the same as to detect the decay products. 41

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43 The R3B Set-up in FAIR simulated with R3BRoot

44 Calorimeter 3 B R&D Engineering design and Mechanical structure based on carbon fibre alveolus Detect with energy resolution < 5% < 30 MeV p < 300 MeV 44

45 Calorimeter 3 B R&D General design of the detector based on kinematical considerations BARREL ~130 ~40 ~20 Egg shape Highly segmented Thick detection volume Inner radius 30cm Crystal length 13 cm Barrel 3650 crystals = 1.6 Ton Beam FORWARD ENDCAP major challenge! Phoswich LaBr/LaCl? CsI(Tl) kev 45 WG Coordinator: Lola Cortina, Univ. Santiago de Compostela

46 Calorimeter 3 B R&D General design of the detector based on kinematical considerations BARREL ~130 ~40 ~20 Egg shape Highly segmented Thick detection volume Inner radius 30cm Crystal length 13 cm Barrel 3650 crystals = 1.6 Ton Beam FORWARD ENDCAP major challenge! Phoswich LaBr/LaCl? CsI(Tl) kev 46 WG Coordinator: Lola Cortina, Univ. Santiago de Compostela

47 CALIFA s Requirements (CALorimeter for In-Flight gamma detection) PROPERTIES REQUIRED VALUES σ Esum γsumenergy E sum <10% σ N N Goodγenergyresolution 3-5 % ΔE E Good light chargedparticleenergyresolution < 3 % ΔE Ep p Prime mission: measure γ (50 kev 25 MeV) with optimal energy resolution (ideally < 5%) R 3 B Calorimeter Collaboration: USC (Spain), LUND (Sweden), IEM (Spain), GSI (Germany), Chalmers (Sweden), Daresbury (UK), Univ. Complutense (Spain), KTH Stockholm (Sweden), IPN Orsay (France), (Russia), TUD (Germany), TUM (Germany) JINR 47

48 CALIFA s Structure Based on angular distribution of emitted γrays and its corresponding Doppler shift which is more important for low than for high polar angles (because of γ rays sources are moving with relativistic energies). Barrel: Region from ~40º up to 130º in polar angles with 45% of gammas rays emitted in this direction Forward endcap: From ~ 7º up to ~40º and concentrates 50% of the total gamma rays emitted by a moving source This region, particularly between 20-40º is extremely complex because it concentrates a large fraction of the gamma emitted. Also the Doppler shift boosts the energy to times its value. Design features: minimum set, reduction of empty space and gammas escaping 48

49 Forward endcap: Phoswich Design of CALIFA's forward endcap. CALIFA has to record: γ-rays in the energy region 50 kev - 25MeV (emitted by a moving source) Protons up to 300 MeV in Lab system The length of the cristals should be selected according to the detection efficiency at different energies Our suggestion: two scintillator crystals layers in a phoswich configuration with only one common readout (crystals must be optically compatibles). The LaBr and LaCl have both very good energy resolution (3-4% for 662 kev gammas and exhibit high light ouput (32+63 phot/kev)). For protons: useful for particle telescope E/E identification: solve ambiguity M.Turrión For gammas: energy efficiency optimization at reduced cost 49

50 Experimental tests Phoswich: LaBr 3 (3 cm) + LaCl 3 (5 cm) Material EnergyResolution (at 662 kev) (%) Light yield (photons/kevγ) Decay time (ns) LaBr LaCl ST. GOBAIN PHOSWICH HAMAMATSU R5380 PMT 50

51 Simulations results for the scintillation experimental tests Array 3x3 Phoswich configuration Geant 4: gamas, 2 MeV Distance: 30 cm and radius of the beam: 2 cm. Coverage of tefflon.

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53 Univ. Santiago de Compostela CHALMERS Technische Universität München Phoswich concept Test beam with protons New G4 simulations: o -rays o Protons Next step: CEPA, towards a final Endcap geometry

54 Phoswich concept 2 scintillator crystals coupled with a common readout. They must be optically compatible. Different light yield and time response Possible to distinguish the signal from the two crystals. 1

55 Test beam with protons March 2009: Protons at 155 MeV and 180 MeV on LaBr 3 -LaCl 3 phoswich detector at TSL (Uppsala) The phoswich configuration has proved to be successful to resolve the two peaks using different techniques 2

56 Geometry to detect Gamma-rays Calorimetry: recover at least 85% of photo-peak energy with 100% efficiency Spectroscopy: good photo-peak efficiency and energy resolution Acceptable price!! 15 cm long and 8 cm wide seems to be a good balance 3

57 Calorimetry: Geometry to absorb Gamma-rays Int. = 87% of the photo-peak energy at 20 MeV 4

58 Calorimetry: Geometry to absorb Gamma-rays Int. = 91% of the photo-peak energy at 20 MeV with full add-back 4

59 Spectroscopy: Optimize Photo-peak efficiency Ph-Peak eff.= 36% at 10 MeV, 16% at 20 MeV and 7% at 30 MeV 5

60 Spectroscopy: Optimize Photo-peak efficiency Ph-Peak eff.: 74% at 10 MeV, 66% at 20 MeV and 56% at 30 MeV with full add-back 6

61 Next step: CEPA CALIFA Endcap Prototype Assembly Demonstrator to check the capabilities of phoswich for both: protons and gamma-rays Towards the final endcap geometry 7

62 Next step: CEPA CALIFA Endcap Prototype Assembly 25 mm 19 mm 15 mm 40 mm 60 mm 8

63 Next step: CEPA CALIFA Endcap Prototype Assembly 9

64 Next step: CEPA Protons up to 120 MeV stopped in the 1 st crystal Protons up to 200 MeV stopped in the 2 nd crystal Bragg curves for E=180 MeV and E=280 MeV 10

65 Next step: CEPA Protons up to 120 MeV stopped in the 1 st crystal Protons up to 200 MeV stopped in the 2 nd crystal Bragg curves for E p =180 MeV and E p =280 MeV: 11

66 CEPA as E-E phoswich detector 12

67 CEPA as E-E phoswich detector 13

68 CEPA as E-E phoswich detector with nuclear reactions included

69 Tests experimentales para radiación gamma MeV) y protones (150 y 180 MeV) Detector cilíndrico de 20 mm de diámetro en configuración phoswich de 3 cm de longitud de LaBr (Ce) acoplado a un cristal de LaCl de 5 cm, cubierto en su base final de un disco de vidrio que se acopla a un fotomultiplicador Hamamatsu de 8 etapas R530 a) CMAM (Madrid, 2009): Radiación gamma

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79 Experimental results vs Montecarlo Simulations

80 Simulations with R3BRppt for the barreñ and the endcap of CALIFA

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83 What is there Inside R3BRoot?

84 The interface and the events

85 15 MeV event visualization

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89 Barrel efficiencies

90 Simulaciones y diseño del end-cap Geometrías propuestas End cap piramidal Endcap triangular Endcap hexagonal Geometría mixta Resolución en angulo polar 3º 2.5º 2º 3º [20º a 40º] 2º [7º a 20º] Tamaño Número de cristales Volumen muerto total 2.1x3.1x15 cm 3 N=636. V=6% 1x1.18x15 cm 3 N=920 V=3% Lado:1.2-1,6 cm Altura: 15 cm N=900 V=5% N=750 V=5.8%

91 Simulations and endcap design Triangular Prisms End-cap CALIFA Θ=2º Phoswich configuration Volume (cm3) Weight # Crystal types End-cap alveole LaBr g 1 LaCl g 1 Alveole kg 9 9 Phoswich crystals Characterisitcs of an alveole

92 Simulations and endcap design Irregular Rectangular Prisms: a very good candidate Different rings Total # crystals Total Weight (kg) End-cap CALIFA Number of rings Phoswich crystal Number of alveoles Angular resolution

93 Simulations and endcap design Configuración phoswich y red hexagonal

94 Simulations and endcap design End cap y barrel ya implementados en R3BRoot

95 Conclussions We have optimized the optimum geometry for phoswich crystals arrays for gamma radiation and protons We have pèrformed experimental tests of protons and gammas with phoswich crystals and the results coincided with the simulations Using this optimum geometry we have developed the front part of the calorimeter and that adpats perfectly to the barrel We have implemented a detector in R3BRoot to obtain results from the simulations previous to experiments in the new R3B branch of the new FAIR

96 Future aims Implement the physics and geometry if the endcap+barrel for R3BRoot Fabricate the endcap and the barrel from the novel results obtained with the simulations Make tests of protons and gammas with Realizar tests de protones y gammas eith fifferent parts of the calorimeter Make nuclear physics experiments of nuclear phhysics in the new R3B Branch of FAIR