Neutrini e cosmologia un update Ofelia Pisanti Dipartimento

Neutrini e cosmologia: un “update” Ofelia Pisanti Dipartimento di Scienze Fisiche e INFN - Napoli IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Primordial Elements Observations BBN Xi Nuclear Astrophysics Nuclear rates B CMB BBN “PDG” stuff: n , GN, a, Physics. . . Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Primordial Elements Observations BBN Xi Nν, ξν Nuclear Astrophysics Nuclear rates BBN Burles, Nollett & Turner, astro-ph/9903300 B CMB “PDG” stuff: n , GN, a, Physics. . . Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Primordial Elements Observations BBN Xi Nν, ξν Nuclear Astrophysics Nuclear rates BBN Barger et al. , PL B 569 (2003) B CMB “PDG” stuff: n , GN, a, Physics. . . Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Primordial Elements Observations BBN Xi Nν, ξν Nuclear Astrophysics Nuclear rates BBN Barger et al. , PL B 569 (2003) B CMB “PDG” stuff: n , GN, a, Physics. . . Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar New Physics?

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Clustering in the universe Massive neutrinos influence structure formation as dark matter Free stream of neutrinos suppress scales smaller than d. FS P(k, τ)=|δ|2(τ)=P 0(k) T(k, τ) Hannestad, NJP 6 (2004) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Clustering in the universe Massive neutrinos influence structure formation as dark matter Free stream of neutrinos suppress scales smaller than d. FS P(k, τ)=|δ|2(τ)=P 0(k) T(k, τ) Hannestad, NJP 6 (2004) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Clustering in the universe Massive neutrinos influence structure formation as dark matter Free stream of neutrinos suppress scales smaller than d. FS P(k, τ)=|δ|2(τ)=P 0(k) T(k, τ) Hannestad, NJP 6 (2004) 2 d. FGRS [Elgarøy et al] 2002 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Clustering in the universe Massive neutrinos influence structure formation as dark matter Free stream of neutrinos suppress scales smaller than d. FS P(k, τ)=|δ|2(τ)=P 0(k) T(k, τ) Hannestad, NJP 6 (2004) SDSS, Tegmark et al. 2003 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” CMB Multipole expansion of temperature fluctuations CMB Angular power spectrum WMAP: the most accurate determination of baryons: b=0. 023± 0. 001 (1 ) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar Max Tegmark’s homepage www. hep. upenn. edu/~max/

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Standard BBN 1. Neutrino decoupling 2. Decoupling of weak rates which keep n and p in chemical equilibrium 3. D formation 4. Nuclear chain a: scale factor : energy density of relativistic species (m < 1 Me. V) e: electron chemical potential Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino decoupling • Neutrinos are in chemical equilibrium with the e. m. plasma till weak reactions freeze out at T ~ few Me. V • In the instantaneous decoupling approximation, there is no overlap in time with e+-e- annihilation: 1. neutrino and photon temperature ratio 2. undistorted distributions 3. standard contribution to energy density Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino distorsions More accurate calculation by solving the kinetic equations Dolgov et. al. , NP B 503 (1997) Mangano et al. , PL B 534 (2002) Effects for BBN ? • weak rates are changed due to larger mean energy of νe and decrease of T/Tν ( ) • decrease of T/Tν Partial entropy transfer during annihilation phase, which results in spectral distorsions (different for νe and νx) Tν 0. 15% larger ρ(νe) 1% larger ρ(νμ, τ) 0. 4% larger f=fv(p, Tν) [1+δf(p)] Neff=3. 04 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar earlier D synthesis ( ) Serpico et al. , JCAP 12 (2004)

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino distorsions More accurate calculation by solving the kinetic equations Dolgov et. al. , NP B 503 (1997) Mangano et al. , PL B 534 (2002) Effects for BBN ? • weak rates are changed due to larger mean energy of νe and decrease of T/Tν ( ) • decrease of T/Tν Partial entropy transfer during annihilation phase, which results in spectral distorsions (different for νe and νx) Tν 0. 15% larger ρ(νe) 1% larger ρ(νμ, τ) 0. 4% larger f=fv(p, Tν) [1+δf(p)] Neff=3. 04 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar earlier D synthesis ( ) Serpico et al. , JCAP 12 (2004)

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Weak rates Freeze out of weak rates determines the final n/p ratio (crucial for 4 He) Big improvements in the last decade: • QED radiative corrections • Finite nucleon mass corrections • Plasma effects • Neutrino distortions Lopez & Turner, PR D 59 (1999) Esposito et al. , NP B 540 (1999) Serpico et al. , JCAP 12 (2004) Rates are accurate at the 0. 1 % level (τn=885. 6± 0. 8 s) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Nuclear rates I Apart for Helium, all the other nuclides are sensitive to the Nuclear reaction Network. Need to properly evaluate thermal averaged nuclear rates and their uncertainties. Main experimental problem: cross section from data in the low energy range of interest for BBN (~0. 01 ~1 Me. V). But: • data from different experiments with different systematics • experimental results typically overlap only partially in energy • for several crucial reactions present data show evidence for ununderstood systematics • cross section for some (at the moment) sub-leading process is still poorly known NEW RESULTS Angulo et al. , NACRE collaboration, 1999 Casella et al, LUNA collaboration, 2002 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Nuclear rates II The choice of the analysis method and error estimate is a non-trivial task!!! Nollet & Burles, PR D 61 (2000) Cyburt, PR D 70 (2004) Cuoco et al. , IJMP 19 (2004) Descouvemont et al. , astro-ph/0407101 We adopted a procedure which involves the minimization of Sik: S factor at Ei of k-th experiment σik: statistical uncertainty Serpico et al. , JCAP 12 (2004) εk: normalization uncertainty (given by experiment) Sth: polynomial fit of the S factor (depending on coefficients a n to be determined by the fit) ωk: offset of the k-th experiment (free parameter determined by the fit) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Nuclear rates III Rate and error estimate Serpico et al. , JCAP 12 (2004) best fit values Boltzmann/Gamow kernel For a reduced χ2 larger than 1 the error is inflated by a factor √ χ2 (PDG prescription) Abundance uncentainties Fiorentini et. al. , RP D 58 (1998) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 2 H status Deuterium is the most sensitive nuclide to ωB: best BBN “baryometer” σNR reduced from 8. 6% to 1. 6% Kirkman et al. , AJS 149 (2003) rate D 2/ D 2 (%) D(p, )3 He 49 D(D, n)3 He 37 D(D, p)3 H Crighton et al. , astro-ph/0403512 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar 14

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 2 H status Deuterium is the most sensitive nuclide to ωB: best BBN “baryometer” σNR reduced from 8. 6% to 1. 6% Essential agreement between two completely independent determinations of ωB!!! et al. , AJSCosmological 149 (2003) Wonderful check of. Kirkman Standard Model rate D 2/ D 2 (%) D(p, )3 He 49 D(D, n)3 He 37 D(D, p)3 H Crighton et al. , astro-ph/0403512 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar 14

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 4 He status observations from BCG (metal poor, extragal. obj. , HII regions) give an unreasonable spread of values, changing with the sample, the regression method to Z=0, the analyzers group… 4 He 2/ 4 He 2 (%) weak p-n 98. 5 D(D, n)3 He 1 σNR < 0. 1% Despite the efforts, the observational side is still “confused”: rate D(D, p)3 H 0. 25 D(n, )3 H 0. 25 Yp=0. 239 ± 0. 002 Yp=0. 2345 ± 0. 0026 Yp=0. 244(5) ± 0. 001 Yp=0. 249 ± 0. 009 0. 232≤Yp ≤ 0. 258 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 4 He status rate 4 He 2/ 4 He 2 (%) weak p-n 98. 5 D(D, n)3 He 1 σNR < 0. 1% D(D, p)3 H 0. 25 D(n, )3 H 0. 25 Despite the efforts, the observational General side is stillagreement among Yp=0. 239 ± 0. 002 “confused”: several groups Error dominated by (δ n/ n)exp observations from BCG (metal poor, extragal. obj. , HII regions) give an unreasonable spread of values, changing with the sample, the regression method to Z=0, the analyzers group… Yp=0. 2345 ± 0. 0026 Yp=0. 244(5) ± 0. 001 Yp=0. 249 ± 0. 009 0. 232≤Yp ≤ 0. 258 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 7 Li status σNR reduced from 30% to 8% 1 < 1010(7 Li /H)exp < 2. 5 In ancient metal poor stars (halo or extragal. ) one finds a plateau (Spite pl. ) for low Z → Hint of Primordial Origin. rate Li 2/ Li 2(%) 7 Be(n, 4 He)4 He 40. 9 4 He(3 He, 25. 1 )7 Be 7 Be(D, p)4 He 16. 2 3 He(D, p)4 He 8. 6 D(p, )3 He 4 others 5. 2 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” 7 Li status σNR reduced from 30% to 8% Still an open problem 1< /H) rate Li 2/ Li 2(%) exp < 2. 5 New clues on Astrophysics? 7 Be(n, 4 He)4 He A window on non-standard physics in the early 40. 9 universe? 1010(7 Li In ancient metal poor stars (halo or extragal. ) one finds a plateau (Spite pl. ) for low Z → Hint of Primordial Origin. 4 He(3 He, )7 Be 25. 1 7 Be(D, p)4 He 16. 2 3 He(D, p)4 He 8. 6 D(p, )3 He 4 others 5. 2 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Joint analyses I CMB+BBN-D (95% C. L. ) BBN-D+4 He (65 and 95% C. L. ) Cuoco et al. , IJMP A 19 (2004) Barger et al. , PL B 566 (2003) (95% C. L. ) Effect of 4 He: shift Neff and ωb towards smaller values. Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Joint analyses II Nv influences the epoch of matter-radiation equivalence Ref. Flat models Non flat models Bound on Nν Data used Crotty et al. , PRD 67 (2003) 1. 4 ≤ Nν ≤ 6. 8 CMB, LSS Hannestad, JCAP 0305 (2003) 0. 3 ≤ Nν ≤ 7. 0 CMB, LSS Hannestad, JCAP 0305 (2003) 2. 3 ≤ Nν ≤ 3. 0 CMB, LSS, BBN Barger, PL B 566 (2003) 1. 7 ≤ Nν ≤ 3. 0 CMB, BBN Cuoco et al. , IJMP 19 (2004) 1. 6 ≤ Nν ≤ 3. 6 CMB, BBN Pierpaoli, MNRAS 342 (2003) 1. 9 ≤ Nν ≤ 6. 62 CMB, LSS Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Joint analyses III Neutrino free-streaming scale depends on the value of neutrino mass Ref. Bound on Σmν (e. V) Data used Spergel et al. , AJS 148 (2003) ≤ 0. 69 CMB, LSS, HST Hannestad, JCAP 0305 (2003) ≤ 1. 01 CMB, LSS, HST Allen et al. , MNRAS 346 (2003) ≤ 0. 56 CMB, LSS, HST Tegmark et al. , PR D 69 (2004) ≤ 1. 8 CMB, LSS Barger et al. , PL B 595 (2004) ≤ 0. 75 CMB, LSS, HST Crotty et al. , PR D 69 (2004) ≤ 1. 0 (0. 6) CMB, LSS (HST) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino asymmetry Electron-positron asymmetry is constrained by the universe neutrality No bounds on neutrinoantineutrino asymmetry Neutrino chemical affects BBN potential Kang & Steigman, NP B 372 (1992) 1) chemical potentials contribute to N 2) a positive electron neutrino chemical potential (more neutrinos than antineutrinos) favour n -> p processes with respect to p -> n processes. Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Degenerate BBN I Hansen et al. , PR D 65 (2002) a I N S N B B + B M +C Hannestad, JCAP 0305 (2003) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Degenerate BBN I Hansen et al. , PR D 65 (2002) a I N S N B B + B M +C Hannestad, JCAP 0305 (2003) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Degenerate BBN I Hansen et al. , PR D 65 (2002) a I N S N B B + B M +C Hannestad, JCAP 0305 (2003) Dolgov et al. , NP B 632 (2002) v oscillations (atmospheric + LMA solar like) mix neutrino asimmetries in different flavors: more stringent bound Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Degenerate BBN I Hansen et al. , PR D 65 (2002) a I N S N B B + B M +C Hannestad, JCAP 0305 (2003) Dolgov et al. , NP B 632 (2002) v oscillations (atmospheric + LMA solar like) mix neutrino asimmetries in different flavors: more stringent bound Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Degenerate BBN II Barger et al. , PL B 569 (2003) B M +C Cuoco et al. IJMP A, 19 (2004) a at d MB +C (95% C. L. ) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar p r o i r ω n o B

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Perspectives BBN • Nuclear physics: new measurements in the energy range of interest for BBN (0. 01 ÷ 1 Me. V) 4 He(3 He, • )7 Be, 2 H-2 H, 7 Be(n, 4 He)4 He, 4 He(d, )6 Li, . . . Astrophysics: better understanding of possible systematics affecting 4 He measurement and 7 Li, but also more data for 2 H CMB • More data (WMAP) and more precision (PLANK) in the observations of CMB. LSS • More data on LSS (SDSS) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Thank you! Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino distorsions More accurate calculation by solving the kinetic equations Dolgov et. al. , NP B 503 (1997) Mangano et al. , PL B 534 (2002) Partial entropy transfer during annihilation phase, which results in spectral distorsions (different for νe and νx) Tν 0. 15% larger ρ(νe) 1% larger ρ(νμ, τ) 0. 4% larger f=fv(p, Tν) [1+δf(p)] Neff=3. 04 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar Esposito et al. , NP B 590 (2000)

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Neutrino distorsions More accurate calculation by solving the kinetic equations Dolgov et. al. , NP B 503 (1997) Mangano et al. , PL B 534 (2002) Partial entropy transfer during annihilation phase, which results in spectral distorsions (different for νe and νx) Tν 0. 15% larger ρ(νe) 1% larger ρ(νμ, τ) 0. 4% larger f=fv(p, Tν) [1+δf(p)] Neff=3. 04 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar Esposito et al. , NP B 590 (2000)

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” QED corrections Sirlin, PR 164 (1967) Marciano & Sirlin, PRL 56 (1986) The neutron lifetime: inner corrections outer corrections perturbative QCD leading log correction resummation Coulomb correction (rescattering of e- in the p field) and weak magnetism nexp = 885. 7 0. 8 s nth = 886. 5 s (0. 1% acc. ) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Plasma effects: Dicus et al. , PR D 26 (1982) Cambier, NP B 209 (1982) … Esposito et al. , NP B 540 (1999) • corrections to n-p rates due to interactions with photons/electrons of the plasma • change in the equations of state of electrons/positrons and photons • thermal contribution to mass of particles Small corrections (<0. 1%) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Some examples Serpico et al. , JCAP 12 (2004) D(p, )3 He LUNA data Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Some examples Serpico et al. , JCAP 12 (2004) D(d, p)3 H Small statistical errors but quite large systematics due to scale normalization poor χ2 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Some examples Serpico et al. , JCAP 12 (2004) D(d, n)3 He Small statistical errors but quite large systematics due to scale normalization poor χ2 Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Some examples Serpico et al. , JCAP 12 (2004) 4 He(3 He, )7 Be Dominant channel for 7 Be production and 7 Li synthesis New measurements progress or planned in ERNA, LUNA Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar

IFAE - Incontri di Fisica delle Alte Energie - Catania – March 31 2005 Neutrini e cosmologia: un “update” Nuclide abundances nuclide central value (exp) (rates) ( b) D/H (10 -5) 2. 44 (2. 78 0. 4) 0. 04 +0. 19 -0. 16 3 He/H(10 -5) 1. 01 0. 03 +0. 02 -0. 03 4 He 0. 2481 (0. 245 0. 007) +0. 0002 – 0. 0001 0. 0004 6 Li/H(10 -14) 1. 1 1. 7 0. 07 7 Li/H(10 -10) 4. 9 (2. 19 0. 5) 0. 4 (mass fraction) Ofelia Pisanti – http: //people. na. infn. it/~pisanti http: //people. na. infn. it/~astropar