Incontro con i referee di CNS3

Milano 28 Febbraio 2014

Isospin dependence of compound Isospin dependence of compound nucleus formation and decaynucleus formation and decay

ISODEC – Scientific Program ISODEC – Scientific Program LOI@SPES 2014LOI@SPES 2014

S.Pirrone – INFN Sezione di CataniaS.Pirrone – INFN Sezione di Catania Steering Committee SPESSteering Committee SPES

Gruppo di Studio SPESGruppo di Studio SPESDocumento per la CNS3Documento per la CNS3

Comitato organizzatore Spes2014 Comitato organizzatore Spes2014

ISOSPINISOSPIN

CHIMERA/FARCOSCHIMERA/FARCOS

Exotic beamsExotic beams

Isospin dependence of compound Isospin dependence of compound nucleus formation and decaynucleus formation and decay

S.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 SPES 2010 Workshop & IV LEA-COLLIGA Meeting

15-19 November 2010 INFN Laboratori Nazionali di Legnaro

LOI @

Isospin dependence of compound nucleus Isospin dependence of compound nucleus formation and decayformation and decay

Guilain ADEMARDGuilain ADEMARD

on behalf of EXOCHIM - ISODEC collaborationon behalf of EXOCHIM - ISODEC collaboration

IPN-Orsay (France)

SPES One Day WorkshopIsospin on reaction mechanism with RIBs’

Catania 8, 9 October 2013

ISODEC - Scientific ProgramISODEC - Scientific ProgramITA-FRA CollaborationITA-FRA Collaboration

Spokes: J.P. Wieleczko GANIL, S. Pirrone INFN-CTSpokes: J.P. Wieleczko GANIL, S. Pirrone INFN-CT M. La Commara Univ. & INFN-Na, G. Politi Univ. & INFN-CT M. La Commara Univ. & INFN-Na, G. Politi Univ. & INFN-CT

Stable Beams Stable Beams -E475S@GANIL , with INDRA (2007)-E475S@GANIL , with INDRA (2007)-ISODEC@LNS , with CHIMERA (2010)-ISODEC@LNS , with CHIMERA (2010)

Next Exotic BeamsNext Exotic Beams-Loi for SPES@LNL -Loi for SPES@LNL -Next proposal for SPIRAL2@GANIL ???-Next proposal for SPIRAL2@GANIL ???

LEA COLLIGA agreement (GANIL_INFN)LEA COLLIGA agreement (GANIL_INFN)J.P. Wieleczko, Lea Colliga Meeting,J.P. Wieleczko, Lea Colliga Meeting, LNL 2007LNL 2007E.Bonnet , Lea Colliga Meeting, LNS 2008E.Bonnet , Lea Colliga Meeting, LNS 2008S.P., Lea Colliga Meeting, Paris 2009S.P., Lea Colliga Meeting, Paris 2009S.P., Lea Colliga Meeting & SPES2010, LNL 2010S.P., Lea Colliga Meeting & SPES2010, LNL 2010G.Politi, Lea Colliga Meeting, Orsay 2011G.Politi, Lea Colliga Meeting, Orsay 2011G.Politi, Lea Colliga-Copigal, Kakow 2012G.Politi, Lea Colliga-Copigal, Kakow 2012S.P., Lea Colliga-Copigal, Paris 2014S.P., Lea Colliga-Copigal, Paris 2014

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)

ISODEC CHIMERA@LNS 2010 ISODEC CHIMERA@LNS 2010

Fasci di CS – uso PSD-Silici – bassa energia Fasci di CS – uso PSD-Silici – bassa energia

78, 86 Kr + 40,48Ca 118, 134 Ba* EE = 10 AMeV= 10 AMeV

• the isospin 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)

• Heavy ion collisions with stable and exotic beam

•Low energy regime E/A ≤ 15 MeV/A

•Fusion reaction mechanism

Physics Case and ContextPhysics Case and Context

Decay modes and emission process are complex and strongly influenced by E*, angular momentum, asymmetry, N/Z composition, nuclear structure

30

35

40

45

50

55

60

100 110 120 130 140 150 160 170 180

Bar

rièr

e Fi

ssio

n (M

eV) p

our

L=0

Masse

sym

=35 MeV

sym

=30 MeV

30

35

40

45

50

55

60

100 110 120 130 140 150 160 170 180

Bar

rièr

e Fi

ssio

n (M

eV) p

our

L=0

Masse

sym

=35 MeV

sym

=30 MeV

Constraints on LDMConstraints on LDM

72Kr + 40Ca 96Kr + 48Ca

Liquid Drop Model predictionsLiquid Drop Model predictions

ES=as(1-ksI2)A2/3

sym=asks

Fission barrier - Esymmetry

P.Moller et al., NPA361,117 (1981)

as surf. energy costant

ks surf. asymmetry costant

Sobotka et al, PRC36(1987)

Even-Odd staggering effect in the IMF

σ measurement – comparison with literature dataJing et al, PRC49(1994)

CN neutron rich (o)

•30% less fission (Z Z 14 14 )

•Less even-odd staggering of IMF ( 6 6 ≤≤ Z Z ≤≤ 12 ) 12 )

FF

IMF

G. Ademard et al. PRC 83 (2011) 054619

E475S INDRA @GANIL EE475S INDRA @GANIL E = 5.5 AMeV= 5.5 AMeV78, 82 Kr + 40 Ca 118,122Ba* (~ 100 MeV)

3≤ ≤ 44° IC-Si-CsI forward part

•Energy, angular and charge distribution of RP

•Cross section decay mode

• 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 consideredG. Ademard et al. PRC 83 (2011) 054619

DSN (di-nuclear system) -model

Sh.A.Kalandarov et al.

PRC82 (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

Dynamical model

DNS in competition to CN

Quasi-fission phenomena

N/Z dependence not considered

G. Ademard et al. PRC 83 (2011) 054619

ISODEC CHIMERA@LNS EISODEC CHIMERA@LNS E = 10 AMeV= 10 AMeV

78, 86 Kr + 40,48Ca 118, 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

• Exclusive measurements in a large angular range

 CN 118Ba 134Ba

E*(MeV) 215 270

VB(MeV) 90 87

ECM/VB 2.9 3.5

(N/Z)tot 1.11 1.39

PSD in Silicon PSD in Silicon ΔΔE-E , Si-CsI(Tl)E-E , Si-CsI(Tl)

IMF Isotopic IdentificationIMF Isotopic Identification

ΔΔE-E , Si-CsI(Tl)E-E , Si-CsI(Tl)

Identificazione Isotopica IMFIdentificazione Isotopica IMF

n-rich n-poor

10Be

9Be

IMF Isotopic IdentificationIMF Isotopic Identification

Li Be B Li Be B

A=9A=9

A=10A=10

A=9A=9A=7A=7

n-rich n-rich 8686Kr + Kr + 4848Ca 10 AMeV, Ca 10 AMeV, ϑϑ=12°=12°n-poor n-poor 7878Kr + Kr + 4040Ca Ca

IMF Mass DistributionIMF Mass Distribution

Different isotopic compositions and relative enrichment for the same Z in the two systems

Carbon Mass DistributionCarbon Mass Distribution

ϑϑ = = 1515° ° (Ring 12)(Ring 12)

n-richn-rich

Carbon Isotopes Energy Spectra (CM)Carbon Isotopes Energy Spectra (CM)

Tesi B.Gnoffo 2013

n-poorn-poor

Carbon Isotopes Energy Spectra (CM)Carbon Isotopes Energy Spectra (CM)

Tesi B.Gnoffo 2013

n-poor n-rich

Normalized Yields Comparison PRELIMINAR 10.5° ≤ ϑ ≤ 15.5°

Tesi B.Gnoffo 2013

86 Kr + 48Ca 78Kr + 40Ca

- 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)

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

- 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

Prossimo futuro Prossimo futuro

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).

LOI@SPESLOI@SPES

From early prompt neck fragmentation to PLF dynamical fission

Binary

break-up

The time-scale of the process as a function of the incident energy and impact parameter could be the main signature among different mechanisms:

1)Early neck fragmentation (40-120 fm/c)2)Dynamical fission (120-300 fm/c3)Equilibrated fission (>1000 fm/c)

The time-scale of the process as a function of the incident energy and impact parameter could be the main signature among different mechanisms:

1)Early neck fragmentation (40-120 fm/c)2)Dynamical fission (120-300 fm/c3)Equilibrated fission (>1000 fm/c)

With respect to the prompt neck emission, the emission of heavy IMFs from projectile-like fragment break-up appears at a later stage

With respect to the prompt neck emission, the emission of heavy IMFs from projectile-like fragment break-up appears at a later stage

Requirement:Z2F=ZH+ZL= 37-57 Zproj=50

Heavy Light

P. Russotto et al. , submitted, PRC (2014)P. Russotto et al. , submitted, PRC (2014)

Probability ratio of dynamical and statistical emission

Cross-sections

Dynamical component: enhanced in the neutron rich (especially for heavier IMF)Statistical component: almost equal (A ratio: 188/170 1.1)

Comparison of IMFs cross sections for 124Sn+64Ni and 112Sn+58Ni

System N/Z Projectile

N/Z target

N/Z compound

124Sn+64Ni 1.48 1.29 1.41

124Xe+64Zn 1.30 1.13 1.24

112Sn+58Ni 1.24 1.07 1.18

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.

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.

4 telescopes 25 cm from the targetlab 16-44 deg, 45 deg4 telescopes 25 cm from the targetlab 16-44 deg, 45 deg

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)

DSSSD 1500 μm (2nd stage) DSSSD 300 μm (1st stage)

132 ch. by each cluster

The InKiIsSy (INverse KInematics ISobaric SYstems) April 2013

Studio con fasci stabili (LNS) e esotici a bassa energia (@SPES) dell’influenza dell’isospin sul meccanismo di Dynamical Fission in 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), …)

A.A. Stefanini et al, Zeit. Phys. A 351, 167 (1995)

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

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 ELOI@SPES E ==10 AMeV10 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 = 140Ba92Kr+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

time resolution ∆t ≤ 1ns

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 @SPESIpotesi di strumentazione @SPES

•CHIMERA@LNLCHIMERA@LNL

•Part of CHIMERA + existing detectors @LNLPart of CHIMERA + existing detectors @LNL

•New detector New detector

FARCOS +….FARCOS +….

FAZIA, TRACE, ……FAZIA, TRACE, ……

Possibili nuove collaborazioniPossibili nuove collaborazioni

EXOCHIM – ISODEC collaborationEXOCHIM – 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