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Alain Coc CSNSM (Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay) +material from: F. Hammache, N. de Séréville, F. de Oliveira, V. Tatischeff,

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Presentation on theme: "Alain Coc CSNSM (Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay) +material from: F. Hammache, N. de Séréville, F. de Oliveira, V. Tatischeff,"— Presentation transcript:

1 Alain Coc CSNSM (Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay) +material from: F. Hammache, N. de Séréville, F. de Oliveira, V. Tatischeff, J. Margueron Nuclear Astrophysics in France  13 (IN2P3 & CEA) Laboratories: CENBG (Bordeaux), GANIL (Caen), LPC Caen, LPSC (Grenoble), Subatech (Nantes), LUPM (Montpellier), CSNSM (Orsay), IPNO (Orsay), LLR (Palaiseau), APC (Paris), Irfu/SPhN & Irfu/SAp (Saclay), IPHC (Strasbourg)  Collaboration with Institut National des Sciences de l'Univers (INSU) Laboratories: IAP (Paris), IRAP (Toulouse),....

2  Motivations:  Source of stellar energy, stellar evolution  Origin of the elements (elemental and isotopic abundances)  Constraints on astrophysical models: Stellar surface abundances, nuclear gamma-ray emission, meteorites,…  Application in astroparticles, cosmological and fundamental physics: Cosmic rays, primordial nucleosynthesis, variation of constants,.…  An interdisciplinary domain by nature Nuclear Astrophysics

3 Primordial nucleosynthesis Hydrogen burning Helium burning e-process (iron peak) “x”-process (Li, Be, B): non- thermal nucleosynthesis r-process (“rapid” n-capture) s-process (“slow” n-capture) p-process (proton rich) Subsequent burning processes ( 12 C+ 12 C, 16 O+ 12 C, 16 O+ 16 O) Origin of the Elements Already a long history [B 2 FH], also in France (in the 60’s) BBN, LiBeB

4 Direct measurements Very small cross sections Indirect measurements Transfert reactions 13 C( 7 Li,t) 17 O [ 13 C( , n) 16 O] Resonant elastic diffusion 12 C( ,  ) 12 C [ 12 C( ,  ) 16 O] Coulomb dissociation 6 Li(  *,  )D [D( ,  ) 6 Li] Trojan Horse Method D( 7 Li,  )n [ 6 Li(p,  ) 4 He] Model dependent Gamow window Direct/indirect measurements 12 C( ,  ) 16 O, 14 C( ,  ) 18 O, 18 O( ,  ) 22 Ne et 22 Ne( ,  ) 26 Mg NUPPEC Long Range Plan Most important reactions Required precision: 10 %

5  BBN calculation of of 4 He, D, 3 He, 7 Li primordial abundances at Planck baryonic density compared with observations.  Used to constrain new physics e.g. variation of “constants”, exotic particles,..., but...  The Lithium Problem: a factor of 3 7 Li overproduction  Observations? New physics? or  A nuclear solution ? New 7 Be destruction channels (decays to 7 Li) 7 Be+ 3 He→ 10 C*, 7 Be+α→ 11 C* Primordial Nucleosynthesis 7 Li from 7 Be decay

6 He shell No obvious additional state in 10 C at ~ 15 MeV nat B( 3 He,t) 11 C No additional state in 11 C at ~ 7.8 MeV If present   total  590 keV (95% CL) Rules out a nuclear solution [Hammache+ 2013] ( 3 He,t) reaction on 10,11 B targets with the Split-pole magnetic spectrometer at the Orsay Tandem Search for unknown states in 10 C and 11 C 10 B( 3 He,t) 10 C

7 (Explosive) Hydrogen burning: two examples Spectroscopy of 19 Ne for 18 F(p,  ) 15 O reaction Ganil experiment [Mountford+ 2012] / predictions [Dufour & Descouvemont 2007] 19 F( 3 He,t) 19 Ne experiment at Orsay [IPNO, York, Barcelona] in 2014 The 17 O(p,  ) 14 N and 17 O(p,γ) 18 F reactions (PAPAP, now at Democritos) ”on”/”off” resonnance [Chaffa+ 2005; 2007]

8  s-process nucleosynthesis → half of the heavy elements  90<A<209  low mass AGB stars 1-3 M  (T  10 8 K) → neutron source 13 C( ,n) 16 O  Split-Pole Orsay Tandem : 13 C( 7 Li,t) 17 O  Drotleff 93  Brune 93 Orsay 3/2 + Gamow peak Clark et al. 6.356 (1/2 + ) S  =0.25S  =0.35 1/2 + The crucial role of the 6.356 MeV sub-threshold state is confirmed [Pellegriti+ 2008] S(E)=E  (E)exp(2  ) 1/2 s-process neutron source: 13 C(α, n) 16 O Also applied to the most important reaction for He burning: 12 C(α, γ) 15 O [Oulebsir+ 2012]  2  ?  S  ? 13 C+  6.359 6.356 1/2 + 5.939 1/2 - 16 O+n 4.554 3/2 - 4.143 3.055 1/2 - 7.166 5/2 - 7.380 5/2 -  nn E cm 0.0 5/2 + 17 O

9 Study of 26 Al(n,p) 26 Mg and 26 Al(n,α) 23 Na  1.809 MeV from 26 Al observed (COMPTEL, INTEGRAL, RHESSI)  Origin: explosive Ne/C burning  Important: 26 Al(n,p) 26 Mg & 26 Al(n,α) 23 Na  Inelastic reaction: 27 Al(p,p') 27 Al* More than 30 new resonances above S n observed with Split-Pole: p & α in coincidence (DSSSDs) → Γ p /Γ & Γ α /Γ Opens up new possibilities e.g. Γ p /Γ for 30 P(p,γ) [Benamara+ submitted]

10  No r-process path : 1000’s nuclei and 10000’s rates (n-capture, lifetimes, fission, neutrinos,....) ⇒ massive input from theory (phenomenological→microscopic) Spectroscopy, decay, masses, t1/2, Pn (ALTO, DESIR) After post-acceleration ex : 130 Cd(d,p) 131 Cd, et 134 Sn(d,p) 135 Sn (SPIRAL 2) r-process  r-process nucleosynthesis → the other half of the heavy elements  Presently most favored astrophysical origin: coalescence of two neutron stars [S. Goriely, ULB, priv. comm.]

11 Non thermal reactions LiBeB from CNO spallation, γ from solar flares [ 511 keV, 56 Fe*, 24 Mg*, 20 Ne*, 2.22 MeV, 12 C*, 16 O*; E/A= 2-100 MeV ] and cosmic rays RHESSI Observations γ-ray production cross sections: Projectile+target = p,  + 12 C, 14 N, 16 O, Ne, 24 Mg, Si, Fe and 3 He + 16 O, 24 Mg [Benhabiles+ 2010] Energies: 5 to 25/40 MeV (Orsay) → 66 MeV (2014) and 200 MeV (2015) [iTemba, Orsay, Algiers] Total  -ray emission cross section

12 Nuclear physics of dense matter Adapted from Demorest et al. (2010) Nucleonic matter Exotic hadronic matter Strange- quark matter Neutron stars are the ultimate states of massive stars (i.e. with 10<M/M  <100) that exploded as SN. Nuclear conditions not reproducible in laboratory Theory [U. van Kolck talk] :  EoS of dense matter? (Internal composition, stiffness, 2 M  NS)  Transition from surface nuclei to core uniform matter via “pasta” ?  Superfluidity (cooling, “glitches”)  Electro-weak processes  Hyperonic matter Experiments:  nuclear masses, giant resonant modes, neutron-skin, pairing, beta-decay, radii,.... (GANIL- SPIRAL 2), hypernuclei,...

13 Other important activities in France  Theory (“diluted” matter): Shell Model, Microscopic (cluster) Model, Mass models, Hauser–Feshbach (TALYS),...  Evaluations: Masses, Thermonuclear rates  Cosmology: BBN, variation of constants  Gamma-ray astronomy:  Observations (INTEGRAL, RHESSI): solar flares, (novae)  Instrumentation: next generation of Compton Telescope  (Micro-)meteorites  Collection: Antartica or from space missions  Extinct radioactivities (→formation of the solar system)

14 Present and future instruments  GANIL-SPIRAL1/2 [F. de Oliveira]  Tandem-ALTO [D. Verney]  ANDROMEDE (Orsay): 1 to 4 MV Van de Graaff and 12 C + 12 C reaction  CACAO (Orsay): Radioactive target production facillity (e.g. 60 Fe, 26 Al, 44 Ti)  Laser MegaJoule (Bordeaux): screening studies, reaction rates. [Jiang+ 2010]


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