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ROGER CABALLERO FOLCH, 1 de juny de 2012 Slide 2 Introduction: Astrophysics and Nuclear Physics motivation Experiment: Setup and detectors BEta deLayEd Neutron detector (BELEN) outlook goals Contents AnalysisBELENIntroductionExperiment Analysis - Ongoing work Slide 3 Current questions in the field of nuclear physics AnalysisBELENIntroductionExperiment Introduction 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 Slide 4 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 Jyvskyl (Finland) INFN-LNL (Italy) GANIL (France) also installations overseas (TRIUMF, RIKEN, etc.) Laboratories AnalysisBELENIntroductionExperiment Introduction Slide 5 Nucleosynthesis in nature Fusion in common stars: from H only He & Li are produced CNO cycle. More nuclei with fusion reaction up to Fe. Beyond Fe nucleosynthesis proceeds through: s-process, r-process, p- process, etc AnalysisBELENIntroductionExperiment Introduction Slide 6 Nucleosynthesis s-process AnalysisBELENIntroductionExperiment Introduction Slide 7 Nucleosynthesis s-process AnalysisBELENIntroductionExperiment Introduction Slide 8 Nucleosynthesis s-process AnalysisBELENIntroductionExperiment Introduction Slide 9 Nucleosynthesis r-process AnalysisBELENIntroductionExperiment Introduction Slide 10 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) AnalysisBELENIntroductionExperiment Introduction Slide 11 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) AnalysisBELENIntroductionExperiment Introduction Slide 12 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) AnalysisBELENIntroductionExperiment Introduction Slide 13 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) AnalysisBELENIntroductionExperiment Introduction Slide 14 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) AnalysisBELENIntroductionExperiment Introduction Slide 15 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) AnalysisBELENIntroductionExperiment Introduction Slide 16 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) AnalysisBELENIntroductionExperiment Introduction Slide 17 State of the art: Knowledge of masses through the years Up to 2004 G. Audi et al., Nucl. Phys. A565, 1(1993); A 595, 409 (1995), A729.337(2003) About 2200 nuclear masses were measured and 3000 nuclides known of 8000 that are assumed to exist. Still far away from the r-process path, Especially for the heavy nuclides. Future RIB facilities: FAIR and RIKEN AnalysisBELENIntroductionExperiment Introduction Slide 18 FAIR (Facility for Antiproton Ion Research) AnalysisBELENIntroductionExperiment Introduction Slide 19 ,n, -decay of exotic (neutron- rich) nuclei... DESPEC requires different types of equipment to study the multiple aspects of the problem -decay Beta delayed neutron detector Neutron spectrometer with AIDA Fast timing array TAS DESPEC (Decay SPECtroscopy) AnalysisBELENIntroductionExperiment Introduction Slide 20 Neutron emission after - decay scheme To measure neutron emission probabilities after beta decay of neutron rich isotopes with relevance in basic nuclear physics, astrophysics and nuclear technology. AnalysisBELENIntroductionExperiment Introduction Slide 21 neutron BETA Example of - delayed neutron emission AnalysisBELENIntroductionExperiment Introduction Slide 22 Motivation Half lives (T 1/2 ) Beta delayed neutron emission probabilities (P n ) Astrophysics (r-process) and nuclear structure: nucleosynthesis aspects of the heavy mass elements. Provide valuable information for the test of theoretical models. Exp. T. Kurtukian et al. Phys. Lett. B (Submitted) DF3 + QRPA + FRDM + QRPA (P.Moeller, et al. 2003) (I.Borzov, et al. 2003) AnalysisBELENIntroductionExperiment S410: Beta-decay measurements of new isotopes near the third r-process peak (N~126) Slide 23 State of the art N=126 t 1/2 existsidentified Area of interest P n (%) QRPA B n = 2-3 MeV Centered AnalysisBELENIntroductionExperiment Slide 24 GSI facility. Fragment separator spectrometer (FRS) Beam characteristics 238 U beam 1GeV/n 2x10 9 ions/s intensity 1.6 g/cm 2 Be target AnalysisBELENIntroductionExperiment Slide 25 Fragment separator spectrometer (FRS). Beam characteristics. SIMBA + BELEN 1.6 g/cm 2 Be target 2x10 9 ions/spill intensity B settings for: 215 Tl, 211 Hg and as references 216 Po, 205 Bi, 135 Sb Spill length ~1s with a period around 4s Separation in flight B E B AnalysisBELENIntroductionExperiment Slide 26 Experimental hall (S4) configuration and setting s TPC MUSIC SLITS SCI DEGRADER ITAG SIMBA & BELEN AnalysisBELENIntroductionExperiment Slide 27 Neutron detector SIMBA Polyethylene shielding AnalysisBELENIntroductionExperiment Experimental hall (S4) configuration and setting s Slide 28 Particle Identification (ID) The separation method based in Time of Flight (ToF) measurement, Energy Loss (E) in the (MUSIC) ionisation chambers and the B fields (B) set. AnalysisBELENIntroductionExperiment IDENTIFICATION: Z and A/Z Slide 29 Implantation detector: SIMBA (Silicon Implantation Detector and Beta Absorber) SIMBA detector Multilayer silicon detector Allows to measure both ion implants and -decays. Decay events can be correlated in time with the detection of neutrons. 2 SSSD (7 segm.) 60x40 mm 2 (1mm thick) XYFRONTA B CREAR Tracking layers XY (60 segm.) 60x60 mm 2 (0.3mm thick) 2 SSSD (7 segm.) 60x40 mm2 (1mm thick) 3 DSSD (implantation area, 60x40 segm.): 60x40 mm 2 (0.7mm thick) Front view AnalysisBELENIntroductionExperiment Slide 30 Neutron detector: BELEN (Beta Delayed Neutron Detector) - Neutron detector designed by UPC GRETER research group (Barcelona) - The detection of the neutron is based on the detection of products of the reaction of the neutron with 3He counters: 3 He + n 3 H + 1 H + 765 keV Ion beam n n n Polyethylene moderator Proportional 3 He counter Silicon decay detector - 30 3 He counters: AnalysisBELENIntroductionExperiment Slide 31 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 AnalysisBELENIntroductionExperiment Slide 32 AnalysisBELENIntroductionExperiment Analysis procedure (Preliminary plots / ongoing) Analysis Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features SCI21-SCI41 ToF TPC21-22 TPC41-42 Position calibration MUSIC 41-42-43 Energy Loss calibration Angle correction of each particle. TPC information. Slide 33 Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features Analysis procedure (Preliminary plots / ongoing) AnalysisBELENIntroductionExperiment Analysis Physical effects along time correction. Slide 34 Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features Analysis procedure (Preliminary plots / ongoing) ID plot evolution in the analysis AnalysisBELENIntroductionExperiment Analysis Slide 35 Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features 205 Bi setting has been used as Z identification reference via isomer gamma rays and 216 Po setting as A/Q checking in the region of interest. Analysis procedure (Preliminary plots / ongoing) A/Q Z 205Bi keV Counts AnalysisBELENIntroductionExperiment Analysis Slide 36 Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features Implants keV Ch Beta disintegrations -SIMBA c alibrations are being performed with a 137 Cs source And alpha lines from a 216Po setting - - decay curves will provide half lives values Implantation Counts Energy deposited (ch) Noise Beta decay Analysis procedure (Preliminary plots / ongoing) AnalysisBELENIntroductionExperiment Analysis Slide 37 -Time correlation between neutron and beta decay - 252 Cf for BELEN efficiency and can be checked with 135 Sb Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features Pulser Noise Neutron signal Counts Energy (ch) Analysis procedure (Preliminary plots / ongoing) First estimation of 210Po halflife of 150 ms. Compatible with literatur results AnalysisBELENIntroductionExperiment Analysis Slide 38 DDAS -Triggerless digital data acquisition system used for the first time in this type of experiments at GSI. -It allows to eliminate the dead time of conventional acquisition systems thanks to the double memory digital cards which allow to acquire data and reading of previously taken data at the same time. -Advantages: 1.Increase the efficiency by about 8% (from 27 to 35%) 2.Flexibility for large time correlation (fundamental to obtain correlations with all neutron and to change the gates offline) 3.Allows to correct some experimental effects, e.g. To reduce neutron background from uncorrelated neutrons. Tracking detectors calibrations & particle ID Particle ID check via 205 Bi isomers, 216 Po -decays SIMBA calibration implantation patterns Analysis of half lives and Pn Digital data acquisition system features Analysis procedure (Preliminary plots / ongoing) AnalysisBELENIntroductionExperiment Analysis Slide 39 Future analysis work Improved ID-Plot via final calibrations of frs detectors Determine implantation rates for each identified isotope Determine implant-beta correlations and neutron-beta correlations Implement an analysis method for deriving half-lifes and for determining beta-delayed neutron emission probabilities. In collaboration with theoreticians, study the impact of these results on nuclear models, as well as on r-process nucleosynthesis calculations. AnalysisBELENIntroductionExperiment Analysis Slide 40 Design of the prototype of the BELEN detector with MCNPX and GEANT4 simulations. Different versions: AnalysisFuture goalsIntroductionExperiment BELEN Tests and experiments with Beta dELayEd Neutron detector (BELEN) Background measurements at GSI and Canfranc underground laboratory. BELEN-20 (20atm) for JYFL. Experiments at JYFLTRAP (Finland). Measurements of delayed neutron emission of fission fragments (UPC, IFIC, CIEMAT): Nov 2009: 95 Rb, 88 Br, 94 Rb, 138 I. (cal. and nucl. Structure) Jun 2010 : 95 Rb, 88 Br, 85 As, 86 As, 85 Ge, 91 Br, 137 I.(decay heat and testing models) BELEN-30 (20 (20atm), 10 (10 atm)) for FRS-GSI. Two experiments at GSI with & SIMBA September 2011, nuclei of astrophysical interest: S323: 127 Pd, 126 Pd, 128 AgS410: 215 Tl, 211 Hg Slide 41 Future goals for the UPC Beta dELayEd Neutron detector (BELEN) AnalysisFuture goalsIntroductionExperiment BELEN Initial plans were for 44 3 He 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. Optimize detection system (BELEN) and its acquisition (DDAS) for future experiments with more exotic beams (FAIR). Prepare for first experiments closer to the r-process path @FAIR/DESPEC (>2018) Measure P xn New experiment at JYFL (Finland) on 2013 New proposals for RIKEN RIB facility in Japan COUNTERS FOR BEta deLayEd Neutron detector Slide 42 The end! Institut de Fsica Corpuscular de Valncia (IFIC) Universitat Politcnica de Catalunya (UPC) Helmholtzzentrum fr Schwerionenforschung 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) Laboratori Nazionali di Legnaro, INFN (Italy) Flerov Laboratory, JINR, Dubna (Russia) CENBG, Universit Bordeaux (France) Thanks to A.Algora, Y.Litvinov and K.Smith for some slides Slide 43 Tomorrow! Slide 44 State of the art FRDM + QRPA K.-L. Kratz, (private communication) r-process path T 1/2 PnPn Exp. T. Kurtukian et al. Phys. Lett. B (Submitted) DF3 + QRPA+ FRDM + QRPA (P.Moeller, et al. 2003) (I.Borzov, et al. 2003) Effect of half-lives The Astr. Jour., 579 (2002), H. Schatz et al. Proc. CGS-13 (2009), G. Martinez-Pinedo K.-L. Kratz, (private communication)