8πLP-CORSET TOF Spectrometer for FF 8πLP - INFN-LNL
Transcript
8πLP-CORSET TOF Spectrometer for FF 8πLP - INFN-LNL
8πLP-CORSET TOF TOF Spectrometer Spectrometer for for FF FF 8πLP-CORSET A. Brondi, G. La Rana, R. Moro, M.Trotta, E. Vardaci, INFN and Dipartimento di Scienze Fisiche dell’Università di Napoli A. Chizhov, G.N. Kniajeva, E.M. Kozulin Flerov Laboratory of Nuclear Reactions, JINR, 141980 Dubna M. Cinausero, E. Fioretto, P.F. Mastinu, G. Prete, V. Rizzi Laboratori Nazionali di Legnaro N. Gelli, F. Lucarelli INFN and Dipartimento di Fisica dell’Università di Firenze FIESTA FIssion of Excited Systems at Tandem-Alpi • Dinamica della Fissione in sistemi di fissilita’ intermedia e in sistemi pesanti; • Dipendenza della densita’ dei livelli dall’isospin; Fission time time scale; scale; 1.1. Fission 2. Strength Strength and and Nature Nature of of dissipation: dissipation: 2. one-body or or two-body; two-body; one-body 3. Dependence Dependence of of the the viscosity viscosity on on the the 3. temperature and and on on the the shape. shape. temperature Systems of Intermediate Fissility (χ ≅ 0.5 - 0.6) Î Î ER ER cross cross section section comparable comparable or or larger larger than than the the fission fission cross cross section: section: more more constraints constraints on on the the SM; SM; Î Î larger larger charged charged particle particle multiplicity multiplicity (almost (almost an an order order of of magnitude) magnitude) Î Î role role of of pre-saddle pre-saddle dynamics dynamics enhanced enhanced compared compared to to saddle-to-scission-one saddle-to-scission-one Î Î no no much much data data on on these these systems systems Heavy Fragment Correlations and Identification 200 MeV 32S + 100MoÆ132Ce Light particles Heavy Fragments Δθ = 680-1040 Δθ = 870-1230 GANES <θFF> = 880 GANES <θFF> = 1000 Fission Events Deep Inelastic collisions Ring F-G Ring G-G Instrumental Upgrade 1. Time-Of-Flight Spectrometer for fission fragments (CORSET, 2 arms + 2 arms) 2. New Annular PPAC for ER The CORSET set-up Fragment 1 Target 208Pb, 244Pu, M target Beam 48Ca 58Fe Tof 1 position 1 60° Mproj, Vproj 60° Tof 2 position 2 Fragment 2 θ1,2 E1,2 M1,2 TKE 8πLP-CORSET Stop Start L = 30/35 cm 1. 4 Start and Stop (4 arms, ring F and G) 2. NIM electronics for 2 arms 3. VME 32Ch TDC for 2 arms The Start-Stop assembling YLF XLF SpLF YLG XLG Left ring F Left ring G beam target SpLG StLF StLG StRG Right ring G Right ring F StRF SpRG XRG YRG SpRF XRF YRF 8πLP-CORSET QDC HV supply TAC CFD CFD Y2 X2 Sp2 St2 beam St1 Sp1 TAC TAC Y2 X2 TOF2 ADC ADC ADC CFD splitter Gate QDC splitter CFD splitter CFD splitter CFD X1 Y1 CFD CFD HV supply Scheme of coincidence TAC TAC TAC QDC Start TAC Gate ADC TOF1 X1 Y1 dT ADC ADC ADC ADC Electronic modules 1. HV supply - 4 channels 2. QDC - 4 channels 3. CFD - 8 channels 4. TAC - 7 pieces 5. ADC - 7 channels CORSET Mass Resolution Acn = 132 L = 35 Δt = 400ps ΔΜ FWHM = 300ps Fine presentazione 180 MeV 32S + 109Ag: TKE vs. Mass TKE vs. Mass distributions for an intermediate system measured with a CORSET setup