Constraints on the heavy elements production in inhomogeneous Big-Bang nucleosynthesis from light-element observations

2010 ◽  
Author(s):  
Riou Nakamura ◽  
Masa-aki Hashimoto ◽  
Sin-ichiro Fujimoto ◽  
Nobuya Nishimura ◽  
Katsuhiko Sato ◽  
...  
Keyword(s):  
Light Element ◽  
Big Bang ◽  
Heavy Elements ◽  
Big Bang Nucleosynthesis

scholarly journals Big Bang nucleosynthesis with long-lived strongly interacting relic particles

2009 ◽  
Vol 5 (S268) ◽  
pp. 33-38
Author(s):  
Motohiko Kusakabe ◽  
Toshitaka Kajino ◽  
Takashi Yoshida ◽  
Grant J. Mathews
Keyword(s):  
Beta Decay ◽  
Bound States ◽  
Nuclear Reactions ◽  
Interaction Strength ◽  
Light Element ◽  
Big Bang ◽  
Heavy Elements ◽  
Big Bang Nucleosynthesis ◽  
Element Abundances ◽  
Strongly Interacting

AbstractWe study effects of relic long-lived strongly interacting massive particles (X particles) on big bang nucleosynthesis (BBN). The X particle is assumed to have existed during the BBN epoch, but decayed long before detected. The interaction strength between an X and a nucleon is assumed to be similar to that between nucleons. Rates of nuclear reactions and beta decay of X-nuclei are calculated, and the BBN in the presence of neutral charged X0 particles is calculated taking account of captures of X0 by nuclei. As a result, the X0 particles form bound states with normal nuclei during a relatively early epoch of BBN leading to the production of heavy elements. Constraints on the abundance of X0 are derived from observations of primordial light element abundances. Particle models which predict long-lived colored particles with lifetimes longer than ~200 s are rejected. This scenario prefers the production of 9Be and 10B. There might, therefore, remain a signature of the X particle on primordial abundances of those elements. Possible signatures left on light element abundances expected in four different models are summarized.

Big Bang nucleosynthesis, microwave anisotropy, and the light element abundances

2005 ◽  
Vol 752 ◽  
pp. 522-531 ◽  
Author(s):  
A. Coc ◽  
C. Angulo ◽  
E. Vangioni-Flam ◽  
P. Descouvemont ◽  
A. Adahchour
Keyword(s):  
Light Element ◽  
Big Bang ◽  
Big Bang Nucleosynthesis ◽  
Element Abundances

scholarly journals Progress on the BL2 beam measurement of the neutron lifetime

2019 ◽  
Vol 219 ◽  
pp. 03002 ◽  
Author(s):  
Shannon F. Hoogerheide ◽  
Jimmy Caylor ◽  
Evan R. Adamek ◽  
Eamon S. Anderson ◽  
Ripan Biswas ◽  
...  
Keyword(s):  
Light Element ◽  
Big Bang ◽  
Neutron Lifetime ◽  
Big Bang Nucleosynthesis ◽  
Element Abundances ◽  
Cold Neutron Beam ◽  
The Standard Model ◽  
Systematic Effects ◽  
Mixing Matrix ◽  
Beam Technique

A precise value of the neutron lifetime is important in several areas of physics, including determinations of the quark-mixing matrix element |Vud|, related tests of the Standard Model, and predictions of light element abundances in Big Bang Nucleosynthesis models. We report the progress on a new measurement of the neutron lifetime utilizing the cold neutron beam technique. Several experimental improvements in both neutron and proton counting that have been developed over the last decade are presented. This new effort should yield a final uncertainty on the lifetime of 1 s with an improved understanding of the systematic effects.

scholarly journals Big bang nucleosynthesis: an accurate determination of light element yields

2000 ◽  
Vol 568 (1-2) ◽  
pp. 421-444 ◽  
Author(s):  
S. Esposito ◽  
G. Mangano ◽  
G. Miele ◽  
O. Pisanti
Keyword(s):  
Accurate Determination ◽  
Light Element ◽  
Big Bang ◽  
Big Bang Nucleosynthesis

NEUTRINO MASS AND COLD DARK MATTER PARTICLES IN BIG-BANG NUCLEOSYNTHESIS

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2427-2442 ◽  
Author(s):  
TOSHITAKA KAJINO ◽  
MOTOHIKO KUSAKABE ◽  
KAZUHIKO KOJIMA ◽  
TAKASHI YOSHIDA ◽  
DAI G. YAMAZAKI ◽  
...  
Keyword(s):  
Dark Matter ◽  
Neutrino Mass ◽  
Critical Role ◽  
Massive Particle ◽  
Light Element ◽  
Dark Matter Particle ◽  
Big Bang ◽  
Particle Model ◽  
Mass Hierarchy ◽  
Big Bang Nucleosynthesis

Neutrino is a tiny weakly interacting massive particle, but it has strong impacts on various cosmological and astrophysical phenomena. Neutrinos play a critical role in nucleosynthesis of light-to-heavy mass elements in core-collapse supernovae. The light element synthesis is particularly affected by neutrino oscillation (MSW) effect through the ν-process. We propose first that precise determination of sin 2 2θ13 and mass hierarchy can be made by a theoretical study of the observed 7 Li /11 B ratio in stars and presolar grains which are produced from SN ejecta. Theoretical sensitivity in our proposed method is shown to be superior to ongoing long-baseline neutrino experiments for the parameter region 10−4 ≤ sin22θ13 ≤ 10−2. We secondly discuss how to constrain the neutrino mass Σmν from precise analysis of cosmic microwave background anisotropies in the presence of primordial magnetic field. We obtain an upper limit Σmν < 1.3 eV (2σ). Thirdly, we discuss decaying dark-matter particle model in order to solve the primordial lithium problems that the standard Big-Bang nucleosynthesis theory predicts extremely different 6 Li and 7 Li abundances from observations.

STAU-CATALYZED BIG-BANG NUCLEOSYNTHESIS AND NUCLEAR CLUSTER MODEL

2009 ◽  
Vol 24 (11) ◽  
pp. 2076-2083 ◽  
Author(s):  
M. KAMIMURA ◽  
Y. KINO ◽  
E. HIYAMA
Keyword(s):  
Cross Sections ◽  
Cluster Model ◽  
Nuclear Reactions ◽  
Light Element ◽  
Bound State ◽  
Big Bang ◽  
Reaction Cross ◽  
Big Bang Nucleosynthesis ◽  
Model Calculations ◽  
Three Body

Three-body cluster-model calculations are performed for the new types of big-bang nucleosynthesis (BBN) reactions that are calalyzed by a supersymmetric (SUSY) particle stau, a scalar partner of the tau lepton. If a stau has a lifetime ≳ 103s, it would capture a light element previously synthesized in standard BBN and form a Coulombic bound state. The bound state, an exotic atom, is expected to induce various reactions, such as (αX-) + d → 6 Li + X-, in which a negatively charged stau (denoted as X-) works as a catalyzer. Recent literature papers have claimed that some of these stau-catalyzed reactions have significantly large cross sections so that inclusion of the reactions into the BBN network calculation can change drastically abundances of some elements, giving not only a solution to the 6 Li -7 Li problem (calculated underproduction of 6 Li by ~ 1000 times and overproduction of 7 Li +7 Be by ~ 3 times) but also a constraint on the lifetime and the primordial abundance of the elementary particle stau. However, most of these literature calculations of the reaction cross sections were made assuming too naive models or approximations that are unsuitable for those complicated low-energy nuclear reactions. We use a few-body calculational method developed by the authors, and provides precise cross sections and rates of the stau-catalyzed BBN reactions for the use in the BBN network calculation.

Signature of Long-lived Relic Particles on Primordial Light Element Abundances in Big Bang Nucleosynthesis

2010 ◽  
Author(s):  
Motohiko Kusakabe ◽  
Toshitaka Kajino ◽  
Takashi Yoshida ◽  
Grant J. Mathews ◽  
Isao Tanihara ◽  
...  
Keyword(s):  
Light Element ◽  
Big Bang ◽  
Big Bang Nucleosynthesis ◽  
Element Abundances

POSSIBILITY OF A SIGNATURE OF THE RADIATIVE DECAY OF RELIC PARTICLES ON LIGHT ELEMENT ABUNDANCES

2007 ◽  
Vol 22 (25n28) ◽  
pp. 2019-2026
Author(s):  
MOTOHIKO KUSAKABE ◽  
TOSHITAKA KAJINO ◽  
GRANT J. MATHEWS
Keyword(s):  
Radiative Decay ◽  
Light Element ◽  
Big Bang ◽  
Decay Process ◽  
Big Bang Nucleosynthesis ◽  
Element Abundances ◽  
Unstable Particles ◽  
Halo Stars ◽  
Primordial Abundance ◽  
Isotopic Abundances

Recent spectroscopic observations of metal poor stars have indicated that both 7 Li and 6 Li have abundance plateaus as a function of the metallicity. Abundances of 7 Li are about a factor three lower than the primordial abundance predicted by standard big-bang nucleosynthesis (SBBN), and 6 Li abundances are ~ 1/20 of 7 Li , whereas SBBN predicts negligible amounts of 6 Li compared to the detected level. These discrepancies suggest that 6 Li has another cosmological or Galactic origin. Furthermore, it appear that 7 Li (and also 6 Li ) has been depleted from its primordial abundance by some post-BBN processes. We study the possibility that the radiative decay of long-lived particles has affected the cosmological lithium abundances in reality. We calculate the non-thermal nucleosynthesis associated with the radiative decay, and explore the allowed region of the parameters specifying the properties of long-lived particles. We also impose constraints from observations of the CMB energy spectrum. It is found that non-thermal nucleosynthesis could produces 6 Li at the level detected in metal poor halo stars (MPHSs), when the lifetime of the unstable particles is of the order ~ 108 − 1012 s depending on their initial abundance. We conclude that a combination of two different processes could explain the lithium isotopic abundances in MPHSs. First, a non-thermal cosmological nucleosynthesis associated with the radiative decay of unstable particles; and second, about the same degree of stellar depletion of both primordial lithium isotopic abundances. If MPHSs experience 6 Li depletion of factor much greater than ~ 3, the simple radiative decay process can not be the cause of large 6 Li abundances in MPHSs.

NONEQUILIBRIUM DECAYS OF LIGHT PARTICLES AND PRIMORDIAL NUCLEOSYNTHESIS

1988 ◽  
Vol 03 (01) ◽  
pp. 267-277 ◽  
Author(s):  
A.D. DOLGOV ◽  
D.P. KIRILOVA
Keyword(s):  
Light Element ◽  
Big Bang ◽  
Big Bang Nucleosynthesis ◽  
Primordial Nucleosynthesis ◽  
Decay Products ◽  
Light Particles ◽  
Concrete Model

Possible modifications of the standard big-bang nucleosynthesis scenario, which would loosen the bound on the number of neutrino flavors, are examined. A concrete model with light ((mx=O( MeV )) quasistable particles (τx~1 s ) decaying into [Formula: see text] is considered. If the decay products do not thermalize they shift the frozen neutron-to-proton ratio and respectively the abundance of the light element produced primordially. The direction of this shift depends on the parameters of the model. Correspondingly for the particular choice of these parameters the restrictions on the number of neutrino flavors may be considerably weakened.

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