+ Improved nuclear reaction network for a reliable estimate of primordial Deuterium yield Ofelia Pisanti in collaboration with P. Mazzella, G. Mangano, and G. Miele
+ BBN theory status n Theoretical framework well established (in the standard scenario) n Increasingly precise astrophysical data on D and He n Increasingly precise data on nuclear process rates from lab experiment at low energies (~ 0.01-1 MeV) n Baryon density parameter ( Ω b h 2 ) measured very accu- rately by CMB Bayon to photon density ratio Y p (=4 n He4 /n b ) accuracy: weak rates + ν decoupling D, 3 He, 7 Li accuracy: nuclear rates network Pastor & de Salas, JCAP 1607 (2016) no.07, 051 Iocco et al., Phys.Rept. 472 (2009) 1-76 Pitrou et al., Phys.Rept. 754 (2018) 1-66 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Astrophysical observations We cannot observe directly primordial abundances, since stars have changed the chemical composition of the universe. Two strategies: observations in systems negligibly contaminated by stellar 1. evolution; careful account for galactic chemical evolution. 2. For D, the most convenient astrophysical environments are the H I clouds on the line of view of QSO’s at high redshifts with low metallicity (negligible astration of D) and narrow absorption lines (distinguishable isotope shift between D and H). Recent observations and reanalysis of existing data show a plateau as a function of redshift (for z ≥ 2) with a very small scattering for systems with comparable metallicity. Cooke et al., Astrophys.J. 855 (2018) no.2, 102 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Deuterium synthesis Di Valentino et al, Phys.Rev. 0.1% D90 (2014) no.2, 023543 87% 9% 3.8% Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ BBN codes n BBN Wagoner code (Wagoner, 1969&1973) n Kawano code (Kawano, 1988) n … n PArthENoPE (Pisanti et al., 2008) (FORTRAN+Python) n AlterBBN (Arbey, 2012) (C) n PRIMAT (Pitrou et al., 2018) (Mathematica) Today, three public codes. All of them essentially equivalent from the numerical point of view. Pisanti et al., Comput.Phys.Commun. 178 (2008) 956-971 Arbey , Comput.Phys.Commun. 183 (2012) 1822-1831 Pitrou et al., Phys.Rept. 754 (2018) 1-66 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ BBN codes n BBN Wagoner code (Wagoner, 1969&1973) n Kawano code (Kawano, 1988) n … New n PArthENoPE (Pisanti et al., 2008) (FORTRAN+Python) release 2.1 soon! n AlterBBN (Arbey, 2012) (C) n PRIMAT (Pitrou et al., 2018) (Mathematica) Today, three public codes. All of them essentially equivalent from the numerical point of view. Pisanti et al., Comput.Phys.Commun. 178 (2008) 956-971 Arbey , Comput.Phys.Commun. 183 (2012) 1822-1831 Pitrou et al., Phys.Rept. 754 (2018) 1-66 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Nuclear rates Evolution of nuclides determined by cross sections of associated processes. For charged particle induced reactions the astrophysical S-factor is the intrinsic nuclear part of the reaction probability It is fitted by experiments. Problem: data sets cover limited energy ranges and have different normalization errors (in some cases not even estimated). 0.5 20 SC72 SC72 0.4 BR90 0.4 SC KR87B 15 KR87B GR63 KR87M 0.3 S ( MeV b ) S ( MeV b ) KR87M 0.3 S ( eV b ) GR62 BR90 GR95 10 MA 0.2 GR95 0.2 GR95C WA MN51 MN51 5 0.1 GE 0.1 RG85 RG85 LU19 LE06 LE06 0 0.0 0.0 TH14 0.0 0.5 1.0 1.5 2.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 TH14 E ( MeV ) E ( MeV ) E ( MeV ) dp γ ddn ddp Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Nuclear rates Evolution of nuclides determined by cross sections of associated processes. For charged particle induced reactions the astrophysical S-factor is the intrinsic nuclear part of the reaction probability It is fitted by experiments. Problem: data sets cover limited energy ranges and have different normalization errors (in some cases not even estimated). 0.5 20 SC72 SC72 0.4 BR90 0.4 LUNA SC KR87B 15 KR87B GR63 KR87M 0.3 S ( MeV b ) S ( MeV b ) KR87M 0.3 S ( eV b ) results GR62 BR90 GR95 10 MA 0.2 GR95 0.2 GR95C awaited! WA MN51 MN51 5 0.1 GE 0.1 RG85 RG85 LU19 LE06 LE06 0 0.0 0.0 TH14 0.0 0.5 1.0 1.5 2.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 TH14 E ( MeV ) E ( MeV ) E ( MeV ) dp γ ddn ddp Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Analysis methods n Coc2015/Cyburt2016: energy dependence from nuclear physics + normalization from chi-squared Same definition of the overall scaling factor multiplying the astrophysical S-factor: n Serpico2004/present work: standard chi-squared plus a penalty factor that does not allow ω k -1 to be greater than the quoted normalization, ε k : α , ω : scaling Serpico 2004: JCAP 0412 (2004) 010 Coc2015: Phys.Rev. D92 (2015) no.12, 123526 factors Cyburt2016: Rev.Mod.Phys. 88 (2016) 015004 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Data selection Strict selection on data applied by some authors, excluding all experiments with not quoted/too large systematic uncertainty. Example: ratio between ddn and ddp rates should be independent of the nuclear matrix elements. So, deviations may indicate normalization errors. Then, it has been used for discriminating among data sets. 1.3 SC72 1.2 KR87M TH14 GR95 1.1 MN51 RG85 1.0 LE06 BR90 0.9 0.001 0.010 0.100 1 Coc2015: Phys.Rev. D92 (2015) no.12, 123526 Trojan Horse data: Astrophys.J. 785 (2014) However, data within uncertainties seem to be consistent with theoretical ab initio calculation (Arai et al., 2011) once the fitted scaling factors are applied. Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Rate comparison ddp 1.10 6% ddn 1.05 1.10 PArthENoPE2.1 1.00 R 4 PArthENoPE1.0 3% 1.05 CYBURT2004 COC2015 PArthENoPE2.1 0.95 7% 1.00 R 3 PArthENoPE1.0 CYBURT2004 0.90 0.05 0.10 0.50 1 COC2015 3% 0.95 T 9 Update of PArthENoPE (TH data), 0.90 0.05 0.10 0.50 1 difference with CYBURT2004/ T 9 COC2015 is due to different data dp γ selection/analysis 1.00 Update of PArthENoPE 0.95 PArthENoPE2.1 8% (MARCII versus PArthENoPE1.0 R CYBURT2004 AD2011), difference with 0.90 COC2015 CYBURT2004/COC2015 15% MARCUCCI _ I 0.85 is MARCII versus 0.05 0.10 0.50 1 AD2011/MARCI T 9 MARCI: Marcucci et al., Phys.Rev. C72 (2005) 014001 MARCII: Marcucci et al., Phys.Rev.Lett. 116 (2016) no.10, 102501 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Results on Deuterium Adopted values are τ n =879.5 s, Ω B h 2 = 0.02225±0.00016, Δ N eff =0. D/H × 10 -5 PArthENoPE2.1 Coc2018 Cyburt2016 dp γ MARCI 2.52±0.07 2.459±0.036 2.579 * dp γ AD2011 2.58±0.07 dp γ MARCII 2.45±0.07 n Exp. value (Cooke et al, 2018): (2.527±0.030) × 10 -5 n Different nuclear data selection in ddn and ddp and analysis method are responsible for +2.4% difference in D/H between present work (PArthENoPE with dp γ MARCI) and Coc2018. n Good agreement between D/H of present work (PArthENoPE with AD2011) and Cyburt2016 (*Table II of the paper) Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ BBN/CMB analysis n Exp. values: n Ω B h 2 = 0.02242±0.00014 (Planck 2018) n D/H = (2.527±0.030) (Cooke et al., 2018) n Y p = 0.2446±0.0029 (Peimbert et al., 2016) n ddn+ddp = PArthENoPE2.1, dp γ = MARCI or MARCII n D+Planck prior (red) and D+He (only BBN,blue) analyses 4.0 4.0 3.5 3.5 Planck 1- σ Planck 1- σ N eff 3.0 N eff 3.0 band band 2.5 2.5 2.0 2.0 0.021 0.022 0.023 0.024 0.021 0.022 0.023 0.024 Ω B h 2 Ω B h 2 D+Planck MARCI: N eff = 3.04±0.12 MARCII: N eff = 3.28±0.12 Ofelia Pisanti - TAUP 2019, 8-14th September 2019
+ Conclusions n Deuterium theoretical prediction depends on rate determination (analysis method+data selection): 3%/ 7% difference in ddn/ddp rates results in ~2% difference in D/H (at most). New release of PArthENoPE (2.1). n MARCI dp γ consistent with standard scenario (N eff =3), while MARCII gives a slight tension between “only BBN” and “D+CMB” determination of N eff . n Shape of dp γ reaction from ab initio calculations. New data from LUNA experiment will be crucial. Ofelia Pisanti - TAUP 2019, 8-14th September 2019
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