+ Improved nuclear reaction network for a reliable estimate of - - PowerPoint PPT Presentation

+

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 (Ωb h2) measured very accu-

rately by CMB Yp(=4 nHe4/nb) accuracy: weak rates + ν decoupling D, 3He, 7Li accuracy: nuclear rates network

Bayon to photon density ratio

Iocco et al., Phys.Rept. 472 (2009) 1-76 Pitrou et al., Phys.Rept. 754 (2018) 1-66 Pastor & de Salas, JCAP 1607 (2016) no.07, 051

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:

1.

• bservations in systems negligibly contaminated by stellar

evolution;

2.

careful account for galactic chemical evolution. For D, the most convenient astrophysical environments are the HI 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.

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

Cooke et al., Astrophys.J. 855 (2018) no.2, 102

+Deuterium synthesis

0.1% 87% 9% 3.8% Di Valentino et al, Phys.Rev. D90 (2014) no.2, 023543

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.

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

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

+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.

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

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

New release 2.1 soon!

+Nuclear rates

It is fitted by experiments. Problem: data sets cover limited energy ranges and have different normalization errors (in some cases not even estimated). 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

0.0 0.5 1.0 1.5 2.0 5 10 15 20 E(MeV) S(eV b)

SC GR63 GR62 MA WA GE LU19

0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.1 0.2 0.3 0.4 0.5 E(MeV) S(MeV b)

SC72 KR87B KR87M BR90 GR95 MN51 RG85 LE06 TH14

ddn ddp dpγ

0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.1 0.2 0.3 0.4 E(MeV) S(MeV b)

SC72 BR90 KR87B KR87M GR95 GR95C MN51 RG85 LE06 TH14

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

+Nuclear rates

It is fitted by experiments. Problem: data sets cover limited energy ranges and have different normalization errors (in some cases not even estimated). 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

0.0 0.5 1.0 1.5 2.0 5 10 15 20 E(MeV) S(eV b)

SC GR63 GR62 MA WA GE LU19

0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.1 0.2 0.3 0.4 0.5 E(MeV) S(MeV b)

SC72 KR87B KR87M BR90 GR95 MN51 RG85 LE06 TH14

ddn ddp dpγ

0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.1 0.2 0.3 0.4 E(MeV) S(MeV b)

SC72 BR90 KR87B KR87M GR95 GR95C MN51 RG85 LE06 TH14

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

LUNA results awaited!

+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 ωk-1 to be greater than the quoted normalization, εk:

Serpico 2004: JCAP 0412 (2004) 010 Coc2015: Phys.Rev. D92 (2015) no.12, 123526 Cyburt2016: Rev.Mod.Phys. 88 (2016) 015004

α,ω: scaling factors

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. However, data within uncertainties seem to be consistent with theoretical ab initio calculation (Arai et al., 2011) once the fitted scaling factors are applied.

0.001 0.010 0.100 1 0.9 1.0 1.1 1.2 1.3

SC72 KR87M TH14 GR95 MN51 RG85 LE06 BR90

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.

Coc2015: Phys.Rev. D92 (2015) no.12, 123526 Trojan Horse data: Astrophys.J. 785 (2014)

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

+Rate comparison

Update of PArthENoPE (TH data), difference with CYBURT2004/ COC2015 is due to different data selection/analysis Update of PArthENoPE (MARCII versus AD2011), difference with CYBURT2004/COC2015 is MARCII versus AD2011/MARCI ddn ddp dpγ

3% 3% 6% 7% 8% 15% 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

0.05 0.10 0.50 1 0.85 0.90 0.95 1.00 T9 R

PArthENoPE2.1 PArthENoPE1.0 CYBURT2004 COC2015 MARCUCCI_I

0.05 0.10 0.50 1 0.90 0.95 1.00 1.05 1.10 T9 R3

PArthENoPE2.1 PArthENoPE1.0 CYBURT2004 COC2015

0.05 0.10 0.50 1 0.90 0.95 1.00 1.05 1.10 T9 R4

PArthENoPE2.1 PArthENoPE1.0 CYBURT2004 COC2015

+Results on Deuterium

D/H×10-5 PArthENoPE2.1 Coc2018 Cyburt2016 dpγ MARCI 2.52±0.07 2.459±0.036 dpγ AD2011 2.58±0.07 2.579* dpγ 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 dpγ MARCI) and Coc2018.

n Good agreement between D/H of present work (PArthENoPE

with AD2011) and Cyburt2016 (*Table II of the paper) Adopted values are τn=879.5 s, ΩB h2 = 0.02225±0.00016, ΔNeff=0.

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

+BBN/CMB analysis

n Exp. values:

n ΩB h2 = 0.02242±0.00014 (Planck 2018) n D/H = (2.527±0.030) (Cooke et al., 2018) n Yp = 0.2446±0.0029 (Peimbert et al., 2016)

n ddn+ddp = PArthENoPE2.1, dpγ = MARCI or MARCII n D+Planck prior (red) and D+He (only BBN,blue) analyses

MARCI: Neff = 3.04±0.12 MARCII: Neff = 3.28±0.12

0.021 0.022 0.023 0.024 2.0 2.5 3.0 3.5 4.0 ΩB h2 Neff 0.021 0.022 0.023 0.024 2.0 2.5 3.0 3.5 4.0 ΩB h2 Neff

Ofelia Pisanti - TAUP 2019, 8-14th September 2019

Planck 1-σ band Planck 1-σ band D+Planck

+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 dpγ consistent with standard scenario (Neff=3),

while MARCII gives a slight tension between “only BBN” and “D+CMB” determination of Neff.

n Shape of dpγ reaction from ab initio calculations. New

data from LUNA experiment will be crucial.

Ofelia Pisanti - TAUP 2019, 8-14th September 2019