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Incontro con i referee di CNS3 Milano 28 Febbraio 2014. Isospin dependence of compound nucleus formation and decay ISODEC – Scientific Program LOI@SPES 2014 S.Pirrone – INFN Sezione di Catania Steering Committee SPES Gruppo di Studio SPES Documento per la CNS3
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Incontro con i referee di CNS3Milano 28 Febbraio 2014 Isospin dependence of compound nucleus formation and decay ISODEC – Scientific Program LOI@SPES 2014 S.Pirrone – INFN Sezione di Catania Steering Committee SPES Gruppo di Studio SPES Documento per la CNS3 Comitato organizzatore Spes2014
ISOSPIN CHIMERA/FARCOS Exotic beams
Isospin dependence of compound nucleus formation and decayS.Pirrone (INFN – Catania), J.P.Wieleczko (GANIL- Caen), M.La Commara (Univ.& INFN – Napoli), G.Politi (Univ. &INFN – Catania)SPES2010 - LNL, 15-17 November 2010 LOI @
SPES One Day Workshop Isospin on reaction mechanism with RIBs’ Catania 8, 9 October 2013 Isospin dependence of compound nucleus formation and decay Guilain ADEMARD on behalf of EXOCHIM - ISODEC collaboration IPN-Orsay (France)
ISODEC - Scientific Program ITA-FRA Collaboration Spokes: J.P. Wieleczko GANIL, S. Pirrone INFN-CT M. La Commara Univ. & INFN-Na, G. Politi Univ. & INFN-CT Stable Beams -E475S@GANIL , with INDRA (2007) -ISODEC@LNS , with CHIMERA (2010) Next Exotic Beams -Loi for SPES@LNL -Next proposal for SPIRAL2@GANIL ??? LEA COLLIGA agreement (GANIL_INFN) J.P. Wieleczko, Lea Colliga Meeting,LNL 2007 E.Bonnet , Lea Colliga Meeting, LNS 2008 S.P., Lea Colliga Meeting, Paris 2009 S.P., Lea Colliga Meeting & SPES2010, LNL 2010 G.Politi, Lea Colliga Meeting, Orsay 2011 G.Politi, Lea Colliga-Copigal, Kakow 2012 S.P., Lea Colliga-Copigal, Paris 2014
ISODEC CHIMERA@LNS 2010 Fasci di CS – uso PSD-Silici – bassa energia 78, 86 Kr + 40,48Ca118, 134 Ba*E= 10 AMeV S. P. et al., Proc. of FUSION11, EPJ Web of Conf. 17, 16010 (2011) G. Politi et al., Proc. of CNR11 EPJ Web of Conf. 21, 02003 (2012) M.La Commara et al., Proc. of IWM2011, EPJ Web of Conf. 11, 00022 (2012) S. P. et al.,Proc of ICRTNP2012, AIP Conf. Proc. 1524, 7-10 (2013) M.La Commara et al., Proc. Of INPC2013, to be published (2014) S.P. et al, Proc of Echic2013, IOP Conf series, to be published (2014)
Physics Case and Context • Heavy ion collisions with stable and exotic beam • Low energy regime E/A ≤ 15 MeV/A • Fusion reaction mechanism Decay modes and emission process are complex and strongly influenced by E*, angular momentum, asymmetry, N/Z composition, nuclear structure • theisospin dependence(N/Z) of the formation and emission mechanism of complex fragments (IMF, Z≥3) from CN, to extract information on: • level density parameter,(thermal properties, E*, meffective) • fission barrier,(Symmetry, congruence and Wigner E terms) • viscosity,( coupling collective – intrinsic modes, Fermi level)
Fission barrier - Esymmetry Liquid Drop Model predictions Constraints on LDM ES=as(1-ksI2)A2/3 sym=asks as surf. energy costant ks surf. asymmetry costant 72Kr + 40Ca 96Kr + 48Ca P.Moller et al., NPA361,117 (1981)
σmeasurement – comparison with literature data Sobotka et al, PRC36(1987) Jing et al, PRC49(1994) Even-Odd staggering effect in the IMF
E475S INDRA @GANIL E= 5.5 AMeV 78, 82 Kr + 40 Ca118,122Ba* (~ 100 MeV) FF IMF • 3≤ ≤ 44° IC-Si-CsI • forward part • Energy, angular and charge distribution of RP • Cross section decay mode • CN neutron rich (o) • 30% less fission (Z 14 ) • Less even-odd staggering of IMF ( 6 ≤ Z ≤ 12 ) G. Ademard et al. PRC 83 (2011) 054619
• R.J.Charity et al, Nucl.Phys.A483 (1988) •D.Mancusi et al, PhysRev C 82 (2010) Statistical Model Fermi Gas model (level density) Hauser-Feschbach for LCP’s Trantion state model for IMF Z>2 FRLDM barrier from Sierk Structure effect NOT considered G. Ademard et al. PRC 83 (2011) 054619
G. Ademard et al. PRC 83 (2011) 054619 Dynamical model DNS in competition to CN Quasi-fission phenomena N/Z dependence not considered DSN (di-nuclear system) -model Statistical Model Fermi Gas model (level density) Hauser-Feschbach for LCP’s Trantion state model for IMF Z>2 FRLDM barrier from Sierk Structure effect NOT considered Sh.A.Kalandarov et al. PRC82 (2010)
ISODEC CHIMERA@LNS E= 10 AMeV 78, 86 Kr + 40,48Ca118, 134 Ba* • Higher energy • Influence on the amplitude of the staggering, on the temperature of the emitting system. • Isotopic identification of IMF • to investigate the staggering effects looking at the isotopic distribution of IMF. • Exploration of a larger domain in N/Z of the system (stable beam!) • to study the dependence from the N/Z on the mechanism of complex fragment emission from CN • Exclusivemeasurements in a large angular range
IMF Isotopic Identification PSD in Silicon ΔE-E , Si-CsI(Tl)
Identificazione Isotopica IMF IMF Isotopic Identification ΔE-E , Si-CsI(Tl) 10Be 9Be n-rich n-poor
IMF Mass Distribution Li Be B A=9 A=10 A=7 A=9 Different isotopic compositions and relative enrichment for the same Z in the two systems n-rich 86Kr + 48Ca 10 AMeV, ϑ=12° n-poor 78Kr + 40Ca
Carbon Mass Distribution ϑ = 15° (Ring 12)
Carbon Isotopes Energy Spectra (CM) n-rich Tesi B.Gnoffo 2013
Carbon Isotopes Energy Spectra (CM) n-poor Tesi B.Gnoffo 2013
- Influence of the Isospin (N/Z) • influence of nuclear pairing force • influence of structure effects • (M. D’Agostino et al., NPA 861 (2011) 47 ) • Esym connection (models) Tesi B.Gnoffo 2013 Normalized Yields Comparison PRELIMINAR 10.5° ≤ϑ≤ 15.5° 78Kr + 40Ca 86 Kr + 48Ca n-poor n-rich E=10 AMeV
Very preliminary comparison with DiNuclear System (DNS) code Simulation performed for the TOTAL cross section and normalized at Z=5 DNS seems to reproduce slightly better the n-poor system by S.A. Kalandarov -Private communication
Prossimo futuro • - Data analysis are in progress : • ER identification for CN cross section • Exclusive measurements (e.g. coincidence LCP-FF, LCP-ER) • Absolute cross sections calculations for different mechanisms to confirm • these first observations • - Complete comparisons with theoretical predictions sensitive to the isospin influence on the reaction mechanism and fragment production • Produzione articolo entro l’anno • - FASE PREPARATORIA SPES Possibili nuove proposte di esperimento con fasci stabili (anche con nuove osservabili e utilizzando le correlazioni (FARCOS)) (LNS-GANIL) • - LOI@SPES attività collaborative a vario livello con gruppi nazionali ed internazionali , TUTTO DA DEFINIRE
LOI@SPES Estensione delle problematiche di ISODEC con misure con fasci esotici, in cui possiamo raggiungere alti valori ed ampi intervalli di N/Z e studiare l’influenza della struttura nucleare sul meccanismo di reazione. Includeremo problematica connessa alla Fissione Dinamica, già da noi studiata a energie intermedie, da studiare a basse energie, con fasci stabili (@LNS –FASE PREPARATORIA SPES) esotici (@SPES).
From early prompt neck fragmentation to PLF dynamical fission Heavy Light With respect to the prompt neck emission, the emission of heavy IMFs from projectile-like fragment break-up appears at a later stage • The time-scale of the process as a function of the incident energy and impact parameter could be the main signature among different mechanisms: • Early neck fragmentation (40-120 fm/c) • Dynamical fission (120-300 fm/c • Equilibrated fission (>1000 fm/c) Binary break-up Requirement: Z2F=ZH+ZL= 37-57 Zproj=50
Comparison of IMFs cross sections for 124Sn+64Ni and112Sn+58Ni P. Russotto et al. , submitted, PRC (2014) Cross-sections Probability ratio of dynamical and statistical emission Dynamical component: enhanced in the neutron rich (especially for heavier IMF) Statistical component: almost equal (A ratio: 188/170 1.1)
The InKiIsSy (INverse KInematics ISobaric SYstems) April 2013 The idea is to use uses a projectile/target combination having the same mass of the neutron rich 124Sn+64Ni system and a N/Z 124Xe+64Zn as the neutron poor one 112Sn+58Ni at the same bombarding energy of 35 A.MeV using the 4π detector CHIMERA and a Farcos module prototype. A new setup: the 4π CHIMERA + 4 modules of FARCOS prototype • Based on (62x64x64 mm3) clusters • 1 square (0.3x62x62 mm3) DSSSD 32+32 strips • 1 square (1.5x62x62 mm3) DSSSD 32+32 strips • 4 60x32x32 mm3 CsI(Tl) crystals (6 cm) 132 ch. by each cluster DSSSD 1500 μm (2nd stage) 4 telescopes 25 cm from the target lab 16-44 deg, 45 deg DSSSD 300 μm (1st stage)
Studio confasci stabili (LNS) e esotici a bassa energia (@SPES) dell’influenza dell’isospinsul meccanismo diDynamical Fissionin prosecuzione degli studi di Chimera a energie intermedie (P.Russotto submitted 2014) e sul break-up veloce nei sistemi pesanti (Au+Au a 15 A.MeV, I. Skwira-Chalot et al. Phys. Rev. Lett. 101, 262701, (2008), …) 100Mo+100Mo and 120Sn+120Sn at 18.7 AMeV Un meccanismo a due step: una reazione deep-inelastic seguita dalla fissione “veloce”(1-5x10-21 sec) di uno dei frammenti primari (3 corpi nello stato finale) che risente fortemente dell’influenza del campo coulombiano dell’altro residuo (effetti di prossimità) e della deformazione del frammento primario. Asymmetric splitting = faster A.A. Stefanini et al, Zeit. Phys. A 351, 167 (1995) Osservato anche a piu‘ bassa energia: P. Glassel et al. Zeit. Phys. A 310, 189 (1983): 84Kr+166Er and 129Xe+122Sn at 12.5 AMeV
LOI@SPES E=10 AMeV ISODEC 94Kr + 40,48Ca 134, 142 Ba* (~320 MeV) (già 2010) DYNAMICAL FISSION in progress….
Study the formation of compound nuclei with same Z and different content in neutron number : • 78,94Kr + 40,48Ca 128,140Ba • Study the formation of the same compound by using two different entrance channel: • CN = 140Ba • 92Kr+48Ca and 128Sn+12C • Study the formation of compound nuclei having the same A but not the same Z. (Proposal for SPIRAL2) • 78Cu+24Mg 102Nb • 78Kr+24Mg 102Cd
Key Observables • Isotopic distribution for IMF • 3≤Z≤12 E = 8÷20 MeV/A 4° < θ < 30° • Energy, angular distribution RP (FF-ER-IMF-LCP) • Charge identification FF (Z < 30) ER (Z < 50) • Cross sections for decay modes • Multiplicity • Relative velocity and angular correlation • Coincidence ER-LCP, FF-LCP, IMF-LCP
Ipotesi di strumentazione @SPES • CHIMERA@LNL • Part of CHIMERA + existing detectors @LNL • New detector • FARCOS +…. • FAZIA, TRACE, …… • Possibili nuove collaborazioni
EXOCHIM – ISODEC collaboration S.P.1, G.Politi1,2, M.LaCommara3,4, J.P.Wieleczko5, G.Ademard5, E.DeFilippo1, M.Vigilante3,4, F.Amorini6, L.Auditore7,8, C.Beck9, I.Berceanu10, E.Bonnet5, B.Borderie11, G.Cardella1, A. Chbihi5, M.Colonna6, A.D’Onofrio4,12, J.D.Frankland5, E.Geraci2,1, B.Gnoffo2, E.Henry13, E.LaGuidara1,14, G.Lanzalone15,6, P Lautesse16, D.Lebhertz5, N.LeNeindre 17, I.Lombardo4, D.Loria7,8, K.Mazurek5, A.Pagano1, M.Papa1, E.Piasecki18, F.Porto2,6, M.Quinlann13, F.Rizzo2,6, E.Rosato3,4, P.Russotto2,6, W.U.Schroeder13, G.Spadaccini3,4, A.Trifirò7,8, J.Toke13, M.Trimarchi7,8, G.Verde1 1) INFN - Catania, Italy 2) Dipartimento di Fisica e Astronomia, Università di Catania, Italy 3) Dipartimento di Scienze Fisiche, Università Federico II Napoli, Italy 4) INFN - Napoli, Italy 5) GANIL - Caen, France 6) INFN LNS - Catania, Italy 7) Dipartimento di Fisica, Università di Messina, Italy 8) INFN Gruppo Collegato di Messina, Italy 9) IN2P3 - IPHC Strasbourg, France 10) IPNE, Bucharest, Romania 11) IN2P3 - IPN Orsay, France 12) Dipartimento di Scienze Ambientali - Seconda Università di Napoli, Caserta, Italy 13) University of Rochester, USA 14) Centro Siciliano Fisica Nucleare e Struttura della Materia, Catania, Italy 15) Università Kore, Enna, Italy 16) IN2P3 - IPN Lyon, France 17) IN2P3 - LPC Caen, France 18) University of Warsaw, Poland