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β - delayed neutrons measurements and opportunities with BELEN detector

β - delayed neutrons measurements and opportunities with BELEN detector. ROGER CABALLERO FOLCH, 1 de juny de 2012. Introduction. Experiment. Analysis. BELEN. Contents. Introduction: Astrophysics and Nuclear Physics motivation. Experiment: Setup and detectors. Analysis - Ongoing work.

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β - delayed neutrons measurements and opportunities with BELEN detector

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  1. β-delayed neutrons measurements and opportunities with BELEN detector ROGER CABALLERO FOLCH, 1 de juny de 2012

  2. Introduction Experiment Analysis BELEN Contents Introduction: Astrophysics and Nuclear Physics motivation Experiment: Setup and detectors Analysis - Ongoing work BEtadeLayEd Neutron detector (BELEN) outlook goals

  3. Introduction Experiment Analysis BELEN Introduction Current questions in the field of nuclear physics • What are the limits of nuclear existence? • What is the heaviest element we can make? • Do new forms of collective motion occur far from the valley of nuclear stability? • Are there new forms of nuclear matter in very loosely bound nuclear systems? • How does the ordering of quantum states, with all of its consequent implications for nuclear structure and reactions, alter in highly dilute or neutron-rich matter? • Do symmetries seen in near-stable nuclei also appear far from stability and do we observe new symmetries? • How are the elements and isotopes found in the Universe formed? • Where are the sites of the r-process(es) of nucleosynthesis? • What is the nuclear equation of state for neutron stars? • etc, etc. Taken from NUPECC long range plans

  4. Introduction Experiment Analysis BELEN Introduction Experimental resources • Main Experimental Research Activities • Nuclear structure and dynamics • Nuclear astrophysics • Fundamental interactions • Nuclear physics tools and applications • Main Research Facilities • GSI (Germany) • ISOLDE (CERN) • n_TOFF (CERN) • Univ. of Jyväskylä • (Finland) • INFN-LNL (Italy) • GANIL (France) • …also installations overseas • (TRIUMF, RIKEN, etc.) Laboratories • Nuclear force (T=0 pairing) • Structure of nucleons • Reactions with exotic (halo) nuclei • Extending the limits of nuclear chart • Mass measurements • Cross section measurements • Beta decay studies

  5. Introduction Experiment Analysis BELEN Introduction Nucleosynthesis in nature Fusion in commonstars: from H only He & Li areproduced CNO cycle. Morenucleiwithfusionreaction up to Fe. Beyond Fe nucleosynthesis proceeds through: s-process, r-process, p-process, etc

  6. Introduction Experiment Analysis BELEN Introduction Nucleosynthesis s-process

  7. Introduction Experiment Analysis BELEN Introduction Nucleosynthesis s-process

  8. Introduction Experiment Analysis BELEN Introduction Nucleosynthesis s-process

  9. Introduction Experiment Analysis BELEN Introduction Nucleosynthesis r-process

  10. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1940 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  11. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1948 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  12. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1958 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  13. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1968 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  14. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1978 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  15. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1988 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  16. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years Up to 1994 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  17. Introduction Experiment Analysis BELEN Introduction State of the art: Knowledge of masses through the years About 2200 nuclear masses were measured and 3000 nuclidesknown of 8000 thatareassumed to exist. Still far away from the r-process path, Especially for the heavy nuclides. Future RIB facilities: FAIR and RIKEN Up to 2004 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003)

  18. Introduction Experiment Analysis BELEN Introduction FAIR (Facility for Antiproton Ion Research)

  19. -decay Introduction Experiment Analysis BELEN Introduction DESPEC (DecaySPECtroscopy) Beta delayed neutron detector Neutron spectrometer with AIDA β,n, γ-decay of exotic (neutron-rich) nuclei... DESPEC requires different types of equipment to study the multiple aspects of the problem TAS Fast timing array

  20. Introduction Experiment Analysis BELEN Introduction Neutron emission after β- decay scheme To measure neutron emission probabilities after beta decay of neutron rich isotopes with relevance in basic nuclear physics, astrophysics and nuclear technology.

  21. Introduction Experiment Analysis BELEN Introduction Example of β-delayed neutron emission neutron BETA

  22. DF3 + QRPA Introduction Experiment Analysis BELEN Experiment Motivation S410: Beta-decay measurements of new isotopes near the third r-process peak (N~126) Halflives (T1/2) Beta delayedneutronemissionprobabilities (Pn) (I.Borzov, et al. 2003) + FRDM + QRPA Astrophysics (r-process) and nuclear structure: nucleosynthesis aspects of the heavy mass elements. Provide valuable information for the test of theoretical models. (P.Moeller, et al. 2003) Exp. T. Kurtukian et al. Phys. Lett. B (Submitted)

  23. t1/2 exists identified Introduction Experiment Analysis BELEN Experiment State of the art Centered N=126 Area of interest Pn (%) QRPA Bn= 2-3 MeV

  24. Introduction Experiment Analysis BELEN Experiment GSI facility. Fragment separator spectrometer (FRS) Beam characteristics 238U beam 1GeV/n 2x109 ions/s intensity 1.6 g/cm2 Be target

  25. Introduction Experiment Analysis BELEN Experiment Fragment separator spectrometer (FRS). Beam characteristics. 1.6 g/cm2 Be target 2x109ions/spill intensity SIMBA + BELEN Bρ settings for: 215Tl, 211Hg and as references 216Po, 205Bi, 135Sb Spill length ~1s with a period around 4s Separation in flight Bρ – ΔE – Bρ

  26. Introduction Experiment Analysis BELEN Experiment Experimental hall (S4) configuration and settings SIMBA & BELEN SCI ITAG MUSIC TPC DEGRADER SLITS

  27. Introduction Experiment Analysis BELEN Experiment Experimental hall (S4) configuration and settings Polyethylene shielding Neutron detector SIMBA

  28. Introduction Experiment Analysis BELEN Experiment ParticleIdentification (ID) The separation method based in Time of Flight (ToF) measurement, Energy Loss (ΔE) in the (MUSIC) ionisation chambers and the B fields (Bρ) set. IDENTIFICATION: Z and A/Z

  29. Introduction Experiment Analysis BELEN Experiment Implantation detector: SIMBA (Silicon Implantation Detector and Beta Absorber) Multilayer silicon detector Allows to measure both ion implants and β-decays. Decay events can be correlated in time with the detection of neutrons. SIMBA detector XY FRONT A B C REAR 2 SSSD (7 segm.) 60x40 mm2 (1mm thick) Tracking layers XY (60 segm.) 60x60 mm2 (0.3mm thick) 2 SSSD (7 segm.) 60x40 mm2 (1mm thick) 3 DSSD (implantation area, 60x40 segm.): 60x40 mm2 (0.7mm thick) Front view

  30. Introduction Experiment Analysis BELEN Experiment Neutron detector: BELEN (Beta Delayed Neutron Detector) - Neutron detector designedby UPC GRETER researchgroup (Barcelona) - The detection of theneutron is based on thedetection of products of the reaction of the neutron with 3He counters: 3He + n 3H + 1H + 765 keV - 30 3He counters: Polyethylene moderator n n Proportional 3He counter Ion beam Silicon β decay detector n

  31. Introduction Experiment Analysis BELEN Experiment Neutron detector: BELEN (Beta Delayed Neutron Detector) BELEN-30 neutron detector · 10 with 10 atm pressure · 20 with 20 atm pressure Neutron shielding SIMBA inside the matrix BEAMLINE

  32. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) Angle correction of eachparticle. TPC information. SCI21-SCI41  ToF TPC21-22 – TPC41-42  Positioncalibration MUSIC 41-42-43  Energy Losscalibration Tracking detectors calibrations & particle ID Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Analysis of halflives and Pn Digital data acquisitionsystemfeatures

  33. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) Physicaleffectsalong time correction. Tracking detectors calibrations & particle ID Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Analysis of halflives and Pn Digital data acquisitionsystemfeatures

  34. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) ID plot evolution in the analysis Tracking detectors calibrations & particle ID Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Analysis of halflives and Pn Digital data acquisitionsystemfeatures

  35. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) 205Bi setting has been used as Z identification reference via isomer gamma rays and 216Po setting as A/Q checking in the region of interest. Tracking detectors calibrations & particle ID Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Z Analysis of halflives and Pn Digital data acquisitionsystemfeatures 205Bi Counts A/Q keV

  36. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) Tracking detectors calibrations & particle ID • SIMBA calibrations are being performed with a 137Cs source • And alpha lines from a 216Po setting • - β-decay curves will provide half lives values Noise Particle ID check via 205Bi isomers,216Po α-decays Counts Implantation Implants SIMBA calibration implantationpatterns keV Beta disintegrations Beta decay Analysis of halflives and Pn Digital data acquisitionsystemfeatures Energy deposited (ch) Ch

  37. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) • Time correlation between neutron and beta decay • -252Cf for BELEN efficiency and can be checked with 135Sb First estimation of 210Po halflife of 150 ms. Compatible with literatur results Tracking detectors calibrations & particle ID Counts Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Analysis of halflives and Pn Digital data acquisitionsystemfeatures Neutron signal Noise Pulser Energy (ch)

  38. Introduction Experiment Analysis BELEN Analysis Analysisprocedure (Preliminary plots / ongoing) • DDAS • Triggerless digital data acquisition • systemused for thefirst time in this • type of experiments at GSI. • Itallows to eliminatethedead time • of conventionalacquisitionsystems • thanks to thedouble memory digital • cards whichallow to acquire data • and reading of previouslytaken data at thesame time. • Advantages: • Increasetheefficiencybyabout 8% (from 27 to 35%) • Flexibility for large time correlation (fundamental to obtaincorrelationswith all neutron and to changethe gates offline) • Allows to correctsome experimental effects, e.g. To reduceneutronbackgroundfromuncorrelated neutrons. Tracking detectors calibrations & particle ID Particle ID check via 205Bi isomers,216Po α-decays SIMBA calibration implantationpatterns Analysis of halflives and Pn Digital data acquisitionsystemfeatures

  39. Introduction Experiment Analysis BELEN Analysis Futureanalysiswork • ImprovedID-Plot via final calibrations of frs detectors • Determineimplantation rates for eachidentifiedisotope • Determineimplant-betacorrelations and neutron-betacorrelations • Implementananalysismethod for derivinghalf-lifes and for determiningbeta-delayedneutronemissionprobabilities. • In collaborationwiththeoreticians, studytheimpact of theseresults on nuclear models, as well as on r-processnucleosynthesiscalculations.

  40. Introduction Experiment Analysis Future goals BELEN Tests and experiments with Beta dELayEdNeutron detector (BELEN) Design of the prototype of the BELEN detector with MCNPX and GEANT4 simulations. Different versions: • BELEN-20 (20atm) for JYFL. Experiments at JYFLTRAP (Finland). Measurements of β delayed neutron emission of fission fragments (UPC, IFIC, CIEMAT): • Nov 2009: 95Rb, 88Br, 94Rb, 138I. (cal. and nucl. Structure) • Jun 2010 : 95Rb, 88Br, 85As, 86As, 85Ge, 91Br, 137I.(decay heat and testing models) Background measurements at GSI and Canfranc underground laboratory. • BELEN-30 (20 (20atm), 10 (10 atm)) for FRS-GSI. Two experiments at GSI with & SIMBA September 2011, nuclei of astrophysical interest: • S323:127Pd, 126Pd, 128Ag S410:215Tl, 211Hg

  41. Introduction Experiment Analysis Future goals BELEN Futuregoals for the UPC Beta dELayEdNeutron detector (BELEN) • Initial plans were for 44 3He counters. • Now collaboration with GSI & JINR (Dubna) • Plans of new design with 90 counters • (detection efficiency ~70%) • 40 count @ 10 atm UPC (refurbishment) • 10 count @ 10 atm GSI • 40 count @ 4 atm JINR • Combine with Advanced Implantation Detector Array (AIDA), Surrey, UK. • Optimizedetectionsystem (BELEN) and itsacquisition (DDAS) for future experiments withmoreexoticbeams (FAIR). • Prepare for first experiments closer to ther-processpath @FAIR/DESPEC (>2018) • Measure Pxn • New experiment at JYFL (Finland) on 2013 • New proposals for RIKEN RIB facility in Japan COUNTERS FOR BEta deLayEd Neutron detector

  42. The end! Institut de Física Corpuscular de València (IFIC) UniversitatPolitècnica de Catalunya (UPC) HelmholtzzentrumfürSchwerionenforschung GmbH (GSI) NSCL, Michigan State University (MSU-USA) CIEMAT (Madrid) Universidade de Santigo de Compostela (USC) Department of Physics, University of Surrey (UK) CFNUL Universidade de Lisboa (Portugal) School of Physics & Astronomy, U. Edinburgh (UK) Department of Physics, University of Liverpool (UK) STFC, Daresbury Laboratory (UK) LaboratoriNazionalidiLegnaro, INFN (Italy) Flerov Laboratory, JINR, Dubna (Russia) CENBG, Université Bordeaux (France) Thanks to A.Algora, Y.Litvinov and K.Smith for some slides

  43. Tomorrow!

  44. DF3 + QRPA State of the art FRDM + QRPA Pn T1/2 K.-L. Kratz, (private communication) K.-L. Kratz, (private communication) Effect of half-lives + FRDM + QRPA (P.Moeller, et al. 2003) (I.Borzov, et al. 2003) Exp. T. Kurtukian et al. Phys. Lett. B (Submitted) r-processpath The Astr. Jour., 579 (2002), H. Schatz et al. Proc. CGS-13 (2009), G. Martinez-Pinedo

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