Nuclear structure and reactions @IN2P3Selected Higlights

Shell evolution and nuclear interactions

Reactions with weakly bound nuclei

Nuclear Astrophysics

Heavy and SHE

Nuclear symetries

Fundamental interactions

Nuclear collisions / phase transition

Shell evolutions and NN interactions

• Disappearence of the N=28 shell closure

• N~16 shell gap and the location of continuum

• Neutron proton interactions in 92Pd

• Two proton radioactivity

• Physics/status @ ALTO

5 Physical Review Letters, 1 Physical Review C 1 TOP 1% , 1 TOP 10% most quoted papers

Ca

SSi

42Si

-Progressive collapse of N=28 shell closure: E(2+)

42Si

44S

N=28N=20

Collapse of the N=28 shell closure

Ca, Z=20 48Ca

34Si

S, Z=16

Si, Z=14

36S

40Ca

46Ar 48Ar44Ar

43S

-Use of complementary experimental techniques(transfer, in-beam, isomer decay, coulex, deep inelastic)

-Various structures observed (triaxial, prolate, coexistence)-Interpret this in term of nuclear forces (spin orbit, tensor)

Ee- (keV)

1365 keV

e+ e-

e- conv0+

2 0+1

44S

(GANIL, IPNO, LPC Caen, IPHC Strasb)

UK labs + IPN Orsay, GANIL, LPC Caen from IN2P3

Evolution of shell gaps using (d,p) and (d,t) with 20O and 26Ne beams at SPIRALTIARA-MUST2-EXOGAM-VAMOS COLLABORATION

Position sensitive Si Barrel Hyball annular detectors 4 MUST2

SPIRAL1 beams

Exogam

-5

0

5

5

Th

. Neu

tron

SP

E (

MeV

)

10 15 20Neutron Number

14

16d5/2

s1/2

d3/2

d5d5

d3d3

O

s1s1

fp states ?

8

(d,p)

(d,t)20O

Energy [MeV]

3/2+

(3/2+)Prelim

inary

B. Fern

andez

Sn

Location of theunbound d3/2 orbit

• EXOGAM: 11 Clovers with partial shield. ~ 10% for E=1.3 MeV

The Neutron Wall: 50 liquid scintillator detectors. 1n ~ 23%

DIAMANT: 80 CsI(Tl) dets. p or ~ 66%

92Pd spectroscopy using EXOGAM-Nwall-DIAMANT

92Pd:A new spin aligned np coupling schemeB. Cederkall et al. Nature (2010)

92Pd92Pd, exp. 96Pd exp

0+ 0+

(2+ )

(4+ )

(6+ )

2+

4+

6+8+

0

874

1786

2536

0

1415

2099

2530

J=9

Pd4646

92

J=9

J=9 J=9

J=0J=0

Pd5046

96

Spin-aligned pairing Normal pairing

G. De France, GANIL co-spokesperson

• Angular and energy distributions agree with Grigorenko model 3 body decay

ExperimentTheory

Experiment

Theory

angle

Collaboration IN2P3: CENBG, GANIL

Two proton radioactivity: 45Fe, 54Zn

Identification of the heavy ions

Drift of the ionizationelectrons

Heavy ion

Protons

Y

X

Z

45Fe (2p)

CENBG TPC

Future plans @ GSI

ALTO @ OrsayProduction of 5. 1011 f/s by photofission of 238UCx 3 dedicated lines : BEDO (beta-decay), SPECOLOR (colinear spectroscopy) and POLAREX (polarized states)

Laser ion source already in operation for Ga and Cu

BEDO

Specolor

Achievements published so far: Beta-decay spectroscopy of N~50 nuclei (D. Verney IPNO)

increase of intensity coming soon

Reactions with weakly bound nuclei

• Fusion with 6,8He

• Nuclear break up with 6He

Neutron correlations, quantum tunneling in weakly bound nuclei

6Hen

n

8Hen

n

6He+65Cu reaction -> , neutronsEnhancement of pair transferFavour a di-neutron configuration

Neutron transfer dominates Fusion of 8He comparable to 6He !

Di-neutron config. also in Nuclear break-up of 6He (Assié, Scarpaci IPNO, D. Lacroix GANIL)

PRL 103, 232701 (2009) Lemasson, Alahari et al.

Chatterjee, Navin et al.PRL 101, 032701 (2008)

Nuclear astrophysics

• Study of 13C(,n) for AGB stars • Study of 18F destruction in novae• Study of 60Fe destruction in supernovae

• Incompressibility of nuclear matter with N/Z ratio

• 60Fe cosmic ray emittor possibly detected by INTEGRALDestroyed mainly by 60Fe(n,)61Fe reaction

Studied by 60Fe(d,p)61Fe at GANIL

E*

Np 61Fe

S. Giron, F. Hammache, N. de Séréville preliminary

Drotleff 93 Brune 93

Orsay 3/2+

Gamow peak

1/2+

M.G. Pellegriti, F. Hammache et al. PRC 70 (2008) 042801

13C(,n)16O source of neutrons for s process in AGB stars

Studied at Orsay TANDEM using 13C(7Li,t)17O

Nuclear AstrophysicsCollaboration IPNO/CSNSM/GANIL

½+

18F(p,)19Ne

JC Dalouzy, de Oliveira et al. PRL 102 (2009) 162503new

• 18F main source of radiation in novaeDestroyed mainly by 18F(p,)19Ne reaction

Studied by 19Ne(p,p’)18F(p) at LLN

Isospin dependence of the nuclear matter incompressibilityStudy of giant monopole mode in 56Ni and 68Ni

56Ni (5.104pps) @50A.MeVInteraction with d gas in MAYA

C. Monrozeau, E. Khan (IPN Orsay) Phys. Rev. Lett. 100, 042501 (2008)

Linked to nuclear matter incompressibility K∞

Determine its value while increasing isospin value…

L=2

L=0

E*= 13-15MeV

E*= 21-23MeV

dd

[mb/sr]

CM (deg)

Heavy and superheavy elements

• Study of Nb, Fm nuclei

• The cluster structure of 212Po

• Probing Z=120 ‘stability’ from fission times

256Rf

253No246Fm

Spectroscopy of SHE

J. Piot (CSNSM) et al

246Fm

253No,256Rf: K isomers @ Dubna, ANL 246Fm,254No: Fission barrier and dynamics @ JYFL, ANLCSNSM Orsay, IPHC Strasb from IN2P3

Manifestation of clustering in 212Po

A. Astier et al. PRL 104 (2010)042701

Enhanced E1 transitions interpreted as oscillatory motion of the -core distance in 208Pb

35°

148°

Doppler shifted linesTE1< 1ps stopping time

Collab: CSNSM, IPNO VIVITRON + EUROGAM

0 0.2 0.4 0.6 0.8(deg)

Nor

mal

ized

Yie

ld

Fusion-Fission

0

0.2

0.4

0.6

0.8

1

1.20

0.2

0.4

0.6

0.8

1

1.20

0.2

0.4

0.6

0.8

1

1.2

U sequential fission+ ……..

Quasi-elastic (target)

min 0.2 treac > 10-18 s

Blocking technique: evidence for long times at Z=120

treac < tmin(thermal vibrations) min 0.1 tmin 10-18 s INDRA, Collab: IPNO, GANIL, IPNL

Lifetime of SHE nucleus (Z=120) from X rays detection

D. Jacquet (IPNO), M. Morjean (GANIL) et al.

PRELIMINARY

X rays from Z=120 seems to be observedWould be compatible with ‘long’ fission times > 10-18s

Highest Z values come from fissionof compound Z=120 nucleus

Symmetries in nuclei

• Phase transition in A~100 nuclei

• Tetrahedral shapes

Mass measurements of 96,97Kr @ ISOLDE

Critical-Point Boundary for the Nuclear Quantum Phase transition near A=100

S. Naimi, G. Audi (CSNSM) et al. PRL 105 (2010) 032502

No deformation evidenced around A=100 in Kr chain !

Search for Tetrahedral shapes

Huge gaps for tetrahedral configurations

Possible signatures : hindered inter-band E2 transitions and Q0~0

Experimental program JYVL, Orsay, LNL,ANL, ILL

Collaboration TetraNuc IN2P3 : IPHC Strasbourg, IPN Lyon, CSNSM Orsay, IPN Orsay

Hindered E2 in one band-head of 156Gd

Independent Q0 measurement planned…

Fundamental interactionsSuperallowed Fermi interactions: 0+ 0+ β decay between isobaric analogs

CVC hypothesis: Universal weak-vector coupling

Need T1/2, BR, Q

Gamow Teller transitions in mirror systems 29P, 31S : T1/2 - Jyväskylä – 200939Ca : T1/2 – ISOLDE - EPJ A44, 363 (2010)

Perspectives : T1/2, BR - 15O, 21Na, 39Ca @ SPIRAL,23Mg, 31S, 41Sc @DESIR, Jyväskylä or ISOLDE

38Ca : T1/2, BR – LISE/GANIL - 2009 30S : T1/2 – Jyväskylä, Accepted in EPJ A38Ca : T1/2 – ISOLDE - EPJ A44, 363 (2010) 42Ti : T1/2, BR, Q – Jyväskylä, PRC 80, 035502 (2009)26Si : T1/2 – Jyväskylä, EPJ A38, 247 (2008)62Ga : T1/2, BR, Q – Jyväskylä, GSI – 3 publications

Perspectives : T1/2, BR – 14O, 18Ne, 34Ar @ SPIRAL 26Si, 30S, 38Ca, 42Ti @ LISE and Jyväskylä 62Ga, 66As, 70Br, 74Rb, 78Y, 82Nb, 86Tc, 90Rh, 94As, 98In @DESIR 

Collabs IN2P3: CENBG, GANIL

Nuclear collisions / phase transitions

-Isospin dependence of symmetry energy

- Production of superheavy nuclei

Modeling of multinucleon transfer

Shell effects in SHE by means of fission times

Modelling fusion and fission

Experimental study of fission of transuraniumFundamental + applied (VAMOS Gedepeon, Euratom)

Phase transition in nuclear matter Bimodality of fragment distribE. Bonnet et al. PRL 105 (2010) 142701

Collabs: GANIL, IPNO, IPNLINDRA detector

G. Lehaut et al. PRL 104 (2010) 232701

Some ConclusionsIN2P3 physicists:

- Involved in different valuable items of nuclear structure and reactions-Have significant impact in the collaborations -Use various detectors and accelerators (GANIL amounts to about 50%)-Deeply involved in future projects (AGATA, S3, FAZIA, PARIS)

AGATA

B(E2) transitions in 74Znusing plunger method

Proposal: IRFU

This was not a fully inclusive presentation !

Below Fermi energy: stopping (isotropy)

decreases

Study of nuclear stopping in central collisions

INDRA and ALADIN collaborations (G. Lehaut et al.),Phys. Rev. Lett. 104, 232701 (2010)

Stopping systematics for central collisions of symmetric systems INDRA@GANIL,GSI

Isotropy/Stopping

Above Fermi energy: stopping depends on

system size

MEAN FIELD IN-MEDIUM NUCLEON-NUCLEON

COLLISIONS

18F main source of radiation in novaeDestroyed mainly by 18F(p,)19Ne reactionUse 19Ne(p,p’)18F(p) at LLN

Broad resonancein 19Ne

Proton energy distribution

A broad resonance influencing the 18F destruction in novae

½+

18F(p,)19Ne

Dalouzy et al. PRL 102 (2009) 162503

T1/2 = 0,09 s

T1/2 = 0,9 s

84Ga

84Ge 83Ge

624,3

242,4100

306,5

84As83As

1046 247,

7

N=48

0.1 0.2 0.3 0.40

N=50

0.1 0.2 0.3 0.40

N=52

0.1 0.2 0.3 0.40

N=54

0.1 0.2 0.3 0.40

D1S Gogny HFB calculation GCM Bohr dynamics

2+

(4+)

VAMOS

20O(d,t)19O

MUST2

(a)

(c)

20O(d,p)21O (b)

Et (

MeV

)

1

2

3

4

5

2

4

6

8

Ed (M

eV)

E*=1.2 MeV

g.s.

40 60 80 100 120 140 160

10 20 30 40

2

3

4

5

E (

MeV

)

1

Angle (deg)

2.4 2.62.2 2.3 2.5

A/Q

20O(d,pn)20O

Angle (deg)

Energy [MeV]

3/2+

(3/2+)Prelim

inary

B. Fern

andez

Collab: IPHC, IPNO, IPNL,