Nuclear Astrophysics in France Alain Coc CSNSM Centre

Nuclear Astrophysics in France 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 q 13 (IN 2 P 3 & CEA) Laboratories: CENBG (Bordeaux), GANIL (Caen), LPC Caen, LPSC (Grenoble), Subatech (Nantes), LUPM (Montpellier), CSNSM (Orsay), IPNO (Orsay), LLR (Palaiseau), APC (Paris), Irfu/SPh. N & Irfu/SAp (Saclay), IPHC (Strasbourg) q Collaboration with Institut National des Sciences de l'Univers (INSU) Laboratories: IAP (Paris), IRAP (Toulouse), . .

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

Origin of the Elements Already a long history [B 2 FH], also in France (in the 60’s) BBN, Li. Be. B ü Primordial nucleosynthesis ü ü Hydrogen burning ü ü Helium burning • ü e-process (iron peak) ü ü “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+16 O)

Direct/indirect measurements Direct measurements Indirect measurements Model dependent Gamow window • 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] Very small cross sections NUPPEC Long Range Plan Most important reactions 12 C( , )16 O, 14 C( , )18 O, 18 O( , )22 Ne et 22 Ne( , )26 Mg Required precision: 10 %

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

Search for unknown states in 10 C and 11 C • (3 He, t) reaction on 10, 11 B targets • with the Split-pole magnetic spectrometer at the Orsay Tandem He shell 10 B(3 He, t)10 C nat. B(3 He, t)11 C No obvious additional state in 10 C at ~ 15 Me. V No additional state in 11 C at ~ 7. 8 Me. V If present total 590 ke. V (95% CL) Rules out a nuclear solution [Hammache+ 2013]

(Explosive) Hydrogen burning: two examples The 17 O(p, )14 N and 17 O(p, γ)18 F reactions (PAPAP, now at Democritos) 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 ”on”/”off” resonnance [Chaffa+ 2005; 2007] [IPNO, York, Barcelona] in 2014

1/2 s-process neutron source: 13 C(α, n)16 O Ø s-process nucleosynthesis → half of the heavy elements Ø 90<A<209 low mass AGB stars 1 -3 M (T 108 K) → neutron source 13 C( , n)16 O Clark et al. Split-Pole Orsay Tandem : 13 C(7 Li, t)17 O Ecm 7. 380 5/27. 166 6. 359 13 C+ 5/2 - 2 ? S ? 6. 356 1/2+ 5. 939 1/2 - 4. 554 3/2 - 3. 055 1/2 - 17 O S =0. 25 6. 356 (1/2+) n S =0. 35 6. 356 (1/2+) S(E)=E (E)exp(2 ) 4. 143 16 O+n 1/2+ Orsay 3/2+ 0. 0 5/2+ The crucial role of the 6. 356 Me. V sub-threshold state is confirmed [Pellegriti+ 2008] Also applied to the most important reaction for He burning: 12 C(α, γ)15 O [Oulebsir+ 2012] Drotleff 93 Brune 93 Gamow peak

Study of 26 Al(n, p)26 Mg and 26 Al(n, α)23 Na Ø 1. 809 Me. V from 26 Al observed (COMPTEL, INTEGRAL, RHESSI) Ø Origin: explosive Ne/C burning Ø Important: 26 Al(n, p)26 Mg & 26 Al(n, α)23 Na Ø Inelastic reaction: 27 Al(p, p')27 Al* p & α in coincidence More than 30 new resonances above Sn (DSSSDs) → Γp/Γ & Γα/Γ [Benamara+ observed with Split-Pole: submitted] Opens up new possibilities e. g. Γp/Γ for 30 P(p, γ)

r-process Ø r-process nucleosynthesis → the other half of the heavy elements Ø Presently most favored astrophysical origin: coalescence of two neutron stars [S. Goriely, ULB, priv. comm. ] Ø 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, t 1/2, Pn (ALTO, DESIR) • After post-acceleration ex : 130 Cd(d, p)131 Cd, et 134 Sn(d, p)135 Sn (SPIRAL 2)

Non thermal reactions Li. Be. B from CNO spallation, γ from solar flares [511 ke. V, 56 Fe*, 24 Mg*, 20 Ne*, 2. 22 Me. V, 12 C*, 16 O*; E/A= 2 -100 Me. V] 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 Me. V (Orsay) → 66 Me. V (2014) and 200 Me. V (2015) [i. Temba, Orsay, Algiers] Total �-ray emission cross section

Nuclear physics of dense 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] : Ø Eo. S of dense matter? (Internal composition, stiffness, 2 M� NS) Ø Transition from surface nuclei to core uniform matter via “pasta” ? Ø Superfluidity (cooling, “glitches”) Ø Electro-weak processes Ø Hyperonic matter Experiments: Ø nuclear masses, giant resonant modes, neutron-skin, pairing, beta -decay, radii, . . (GANILSPIRAL 2), hypernuclei, . . . Nucleonic matter Strangequark matter Exotic hadronic matter Adapted from Demorest et al. (2010)

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

Present and future instruments q q q GANIL-SPIRAL 1/2 [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 Mega. Joule (Bordeaux): screening studies, reaction rates. [Jiang+ 2010]