Primordial Nucleosynthesis

Transcription

1 Primordial Nucleosynthesis Alain Coc (Centre de Sciences Nucléaires et de Sciences de la Matière, Orsay) q Standard Big-Bang Nucleosynthesis of 4He, D, 3He, 7Li compared with observations q The SBBN lithium problem, search for nuclear or other solutions q Beyond SBBN (CNO, variations of constants, mirror matter, modified gravity... )

2 Three observational evidences for the Big-Bang Model 1. The expansion of the Universe 2. The Cosmic Microwave Background radiation (CMB) 3. Primordial nucleosynthesis Reproduces the light-elements 4 He, D, 3 He, 7 Li primordial abundances over a range of nine orders of magnitudes. ü First Number determination of neutrino of families the number N ν = of 2.984±0.008 light neutrino [LEP families, Nexperiments ν 3 [Yang, 2006] Schramm, Steigman, Rood 1979] ü First Baryonic determination density ρ b of the baryonic -31 g/cmdensity 3 from of CMB the Universe, anisotropies: WMAP ρ b =(1-3) 10 [Hinshaw+ -31 g/cm ], [Wagoner Planck+lensing+WP+highL 1973], need for baryonic [Ade+ dark 2014] matter Ω b h 2 = ± (i.e. 1.5%) with Ω b =ρ b/ ρ critical and η= Ω b h 2, the number of baryon per photon

3 Beyond the Standard Models(s)? See review by Iocco, Mangano, Miele, Pisanti & Serpico 2009 Relic Particle decay [Jedamzik & Pospelov 2009] [Coc, Olive, Uzan & Vangioni 2009] Deviation from General Relativity [P. Descouvemont s talk] Variation of constants

4 The 12 reactions of standard BBN q Much lower density than in stars nucleosynthesis T<1GK T>10GK Standard BBN Ø No convection Ø No diffusion Ø No mixing Ø No screening Ø Known physics Ø 11/12 reactions measured at BBN energies [Serpico+ 2004, Descouvemont+ 2004, Cyburt 2004] Simple problem (?)

5 Determination of primordial abundances Primordial abundances : (see E. Vangioni poster No. 8) 1) Observe a set of primitive objects born when the Universe was young 4 He in H II (ionized H) regions of blue compact galaxies 3 He in H II regions of our Galaxy D in remote cosmological clouds (i.e. at high redshift) on the line of sight of quasars 7 Li at the surface of low metallicity stars in the halo of our Galaxy 2) Possibly extrapolate to zero metallicity : Fe/H, O/H, Si/H,. 0

6 D/H observations in cosmological clouds (see E. Vangioni poster No. 8) (3.02±0.23) (2.53±0.04) 10-5 (1-σ) [Cooke+ [Olive+ 2012] 2013] Protosolar Local ISM 10-5 [X/H]= log ( (X/H) //(X // H ) ) Burles & Tytler 1998; O Meara+ 2001, 2006; Pettini+ 2001, 2008, 2012; Kirkman+ 2003, Crighton+ 2003, Crighton+ 2004; Srianand+ 2004; Srianand+ 2010; Cooke+ 2010; Cooke+ 2011; Fumagalli+ 2011; Fumagalli+ 2011; Cooke

7 Primordial Li from observations [Spite, Spite & Bonifacio 2012] Ø Lifetime of M < 0.9 M stars > 15 Gy Ø Oldest (low metallicity) stars in galactic halo Ø For T eff > 5900 K, no deep convection and no Li surface depletion (?) Ø Li/H = (1.58±0.35) [Sbordone et al. 2010] (log scale : Log(Li/H)+12)! (see E. Vangioni poster No. 8) Li in the Cosmos, Paris, Feb. 2012,

8 Comparison between observed and calculated abundances Limits (1-σ) obtained by Monte-Carlo fusing Descouvemont+ 2004; Ando+ 2006, Cyburt & Davids 2008 reaction rate uncertainties. Concordance (?) BBN, spectroscopy and CMB Ω B h 2 [WMAP: Komatsu+ 2011; Planck: Ade+ 2013] 4 He [Aver+ 2011; 2013] D [Olive+ 2012; Cooke+ 2013] 3 He [Bania et al. (2002)] 7 Li [Sbordone+ 2010] : difference of a factor of 2-3 between calculated (BBN+CMB) and observed (Spite plateau) primordial lithium

9 BBN calculations versus observations BBN calculations Observations Cyburt et al NPA IV 2009 NIC He ± ± ± ± D/H 2.49± ± ± ± He/H 1.00± ± ±0.03 ( ) 10-5 * 7 Li/H ± ± Changes from NPA IV to NIC13 due to: (see E. Vangioni poster No. 8) Ω b h 2 [WMAP5; 7; 9; Planck 2013] τ n [PDG 2008; 2012] CNO network [Coc+ 2012], (neutron drains/sources), sub-leading processes e.g. 7 Be(n,α) 4 He i.e. systematics *[Olive et al. 2013; Cooke et al. 2013; Bania et al. 2002; Sbordone et al. 2010] Add ΔY p = [Dicus+ 1982; Lopez & Turner 1999; Mangano+ 2005]

10 Important reactions for precision BBN ( 7 Li) q 3 He(α,γ) 7 Be ( 7 Li sensitivity 0.97) Ø New precise (prompt, activation, recoil) measurements to resolve previous systematic uncertainties [Brown+ 2007; Confortola+ 2007; Costantini+ 2008; Nara Singh+ 2005, 2013; Brown+ 2007; Gyürky+ 2007; Di Leva+ 2009; Carmona-Gallardo+ 2012; Bordeanu+ 2013;...(?)] Ø New data made our [Descouvemont+ 2004] analysis (S(0) = 0.51±0.04 kev.b) obsolete reanalysis of by Cyburt & Davids 2008 (0.580±0.043) and Adelberger (0.56±0.02±0.02)

11 Important reactions for precision BBN (D) q D(d,n) 3 He (D sensitivity -0.54) Ø New precise (±2%±1%) measurements (together with 2 H(d,p) 3 H) reaction at TUNL [Leonard et al. 2006] Ø Excellent agreement with Descouvemont fit within Gamow window q D(p,γ) 3 He (D sensitivity -0.32) Ø No new measurements since 2002 (LUNA) Ø Excellent agreement between Adelberger and Descouvemont Ø Ab initio calculations [Marcucci+ 2005] higher S(E) at BBN energy [Di Valentino ] Ø Better agreement [Di Valentino+ 2014] with Cooke D observations theo. rate exp. rate Planck [Di Valentino+ 2014]

12 Nuclear solution to the Li problem? At η WMAP 7 Li from 7 Be post BBN decay Tentatives nuclear solutions: 7 Be destruction by: 1. Supplementary reactions e.g. 7 Be(d,p) 8 Be* 2α 2. Extra neutron sources in 7 Be(n,p) 7 Li(p,α) 4 He destruction channel

13 Unknown resonances in other channels? q 7 Be(d,p) 8 Be* cross section enhancement by a factor of 100 would solve the Li problem [Coc+ 2004; Cyburt & Pospelov 2009]. Not confirmed by experiments [Angulo+ 2005; O Malley+ 2011; Scholl+ 2011; Kirsebom & Davids 2011] q 7 Be(n,α) 4 He [Wagoner 1969] could contribute to 7 Be destruction [Serpico+ 2004]. Experimental project with n beam from Liquid Li Target at the Soreq Accelerator Facility [M. Paul s talk] q New resonances in 7 Be + n, p, d, t, 3 He and α i.e. new levels in 10 C, 11 C,... [Chakraborty, Fields & Olive 2011; Broggini et al. 2012]? Be+ 3 He (2+) (2 -, 1 - )? (2 -, 1 - )? (2 + ) C Γ p? B+p Γ α? Be+α

14 Unknown resonances in other channels? Indirect study of 10 C and 11 C states via ( 3 He,t) and ( 3 He,d) reactions on 10 B and 9 Be targets No new 10 C (and 11 C) levels found at Orsay Tandem [Hammache+ 2013]. Rate from experimental upper limits too low by ~ 10 6 factor!

15 More supplementary reactions up to CNO q Applications of extended network: 1. Potential neutron sources for 7 Be destruction by 7 Be(n,p) 7 Li(p,α) 4 He in BBN (the lithium problem)? 2. CNO seeds for first stars : CNO/H > [Cassisi & Castellani 1993] : CNO/H > [Ekström+ 2008] 3. Comparison with non-standard BBN [P. Descouvemont s talk] q New network 391 reaction rates A Z + n, p, d, t, 3 He and α (1<Z<11). Most rates (271) from theory (Talys; ask S. Goriely) 1. Reaction rate variations by factors with reevaluation of selected rates [Coc, Goriely et al. 2012] 2. Monte Carlo calculations [Coc, Uzan & Vangioni 2014], uncertainties abundances, correlations with nuclear rates

16 Monte-Carlo sampling (See also Nishimura s poster for weak-s and p processes MC) Let x be the short notation for a reaction rate: x N A σ v Assumed to follow a Log- Normal distribution: [Longland, Iliadis et al. 2010] f (x) = σ 1 2π 1 x e (ln x µ ) 2 /(2σ 2 ) i.e ln(x) follows a Normal distribution with mean µ and variance σ 2 Monte-Carlo sampling : p follows a Normal distribution with mean 0 and variance 1 [Longland 2012; Sallaska et al. 2013] x k = exp ( µ k + p k σ ) k x ( med f.u. ) p y j (yield of isotope j, reaction k) x med exp ( µ ) f.u. exp( σ ) Evaluated µ(t), σ(t) or estimated x med, f.u. e.g. f.u.=100 for TALYS

17 Monte-Carlo results: improved uncertainties CNO/H>10-13 (2%) Number of atoms [Coc et al. 2012] [Coc et al. 2014] 6 Li/H ( ) * 9 Be/H ( ) * 11 B/H ( ) * CNO/H ( ) * *16%, (50%) and 84% percentiles

18 BBN Monte-Carlo results: correlations «Statistical Methods for Thermonuclear Reaction rates and Nucleosynthesis Simulations» [Iliadis, Longland, Coc, Timmes & Champagne, J. Phys. G submitted] x k;i = exp ( µ k + p k;i σ k ) y j;i Correlation coefficient between yield of isotope j (y j ) and rate of reaction k (p k ) rate: C j,k = Cov(y j, p k ) Var(y j )Var(p k ) Trivial examples in BBN: correlation between 6 Li isotope (=j) and rate of reactions (=k) : T(α,n) 6 Li C j,k 0 D(α,γ) 6 Li C j,k 1 No big surprise! Nor for D, 3 He or 7 Li

19 Non trivial CNO correlations (> 10%) CNO Reaction C jk 12 B(p,α) 9 Be Be(p,α) 7 Li Be(α,n) 13 C Li(t,γ) 10 Be Li(α,n) 11 B Li(t,n) 10 Be Be(t,n) 12 B C(d,α) 11 B Be(p,t)2 4 He Li(d,n)2 4 He Known from the previous analysis [Coc, Goriely et al. 2012]

20 New path of BB nucleosynthesis to CNO? Ø Possible new path for CNO: CNO/H > seeds for first stars requires simultaneously: High 10 Be(α,n) 13 C and 8 Li(t,n) 10 Be rates Low 10 Be(p,α) 7 Li and 10 Be(p,t)2 4 He rates

21 Sensitivity studies results q The lithium problem: Ø No important reaction besides already known [e.g. 7 Be(d,p)2α] Ø No extra neutron source q CNO production: Ø Identification of important reactions from simple sensitivity study Ø Reevaluation of selected rates [e.g. 11 Be(d,n) 12 C] Ø CNO/H confirms Iocco et al but with documented rates (i.e. origin of all rates given) Ø Nuclear uncertainty on CNO/H from Monte Carlo CNO/H= ( ) % confidence level Ø Possible new path for CNO: CNO/H > seeds for first stars Not seen in simple sensitivity studies! To be applied to other nucleosynthesis sites

22 Origin of CMB, SBBN and Li observations discrepancies q Stellar/Galactic? ( Li in the Cosmos 2012 proceedings) Ø Observational bias: 1D/3D, LTE/NLTE model atmospheres, effective temperature scale [Ryan et al. 2000] Ø Li stellar destruction : atomic, turbulent diffusion and mass loss interplay could restore the plateau (with ad hoc parameters) [Richard+ 2005; Vick+ 2013] q Non Standard Model(s)? [Iocco+ 2009; Fields 2011] Ø Variation of fundamental couplings [Berengut+ 2010,2013; Coc+, ] Ø Massive particle decay [Jedamzik 2004,2006;...Cyburt ] or catalyst [Pospelov 2006,...Cyburt+ 2012; Kusakabe+ 2013] Ø Photon cooling by axion [Sikivie & Yang 2009;... Kusakabe+ 2013] Ø (ask T. Kajino, G. Mathews,...)

23 Main collaborators Elisabeth Vangioni, Jean-Philippe Uzan (Institut d Astrophysique de Paris) Keith Olive (U. of Minnesota) Pierre Descouvemont, Stéphane Goriely (Université Libre de Bruxelles) Faïrouz Hammache (IPN, Orsay) Christian Iliadis, Richard Longland (UNC/NCSU, North Carolina)

24 Conclusions q q q SBBN + WMAP in good agreement with D and 4 He observations, but disagreement (factor of 3) with Li observations [Spite, Spite & Bonifacio 2012, Fields 2011] Ø Nuclear : No but important to quantify needed depletion Ø Stellar depletion (diffusion+turbulence+mass loss) [Korn et al. 2006, Richard et al. 2005, Vick+ 2013]? Ø Cosmology or particle physics : dark/supersymmetric particle decay or catalysis, Variation of constants,...? Systematic sensitivity to reaction rates studies (including correlations) are important, not only in BBN: Ø Ø Effects of 1 H(n,γ)D on 7 Li ( 7 Be) and 7 Li(d,n)2 4 He on CNO Possible new path to CNO When looking back in time, Standard BBN is the last milestone of know physics : probe of the physics of the early Universe