EFFECT OF NEGATIVELY-CHARGED MASSIVE PARTICLES ON BIG-BANG NUCLEOSYNTHESIS AND A SOLUTION TO THE LITHIUM PROBLEMS

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1668-1674
Author(s):  
MOTOHIKO KUSAKABE ◽  
TOSHITAKA KAJINO ◽  
RICHARD N. BOYD ◽  
TAKASHI YOSHIDA ◽  
GRANT J. MATHEWS
Keyword(s):  
Charged Particle ◽  
Nuclear Reactions ◽  
Charged Particles ◽  
Big Bang ◽  
Light Nuclei ◽  
Big Bang Nucleosynthesis ◽  
Spectroscopic Observations ◽  
Halo Stars ◽  
Wmap Data ◽  
Ionization Processes

Spectroscopic observations of metal poor halo stars give an indication of a possible primordial plateau of 6 Li abundance as a function of metallicity similar to that for 7 Li . The inferred abundance of 6 Li is ~1000 times larger than that predicted by standard big bang nucleosynthesis (BBN) for the baryon-to-photon ratio inferred from the WMAP data, and that of 7 Li is about 3 times smaller than the prediction. We study a possible solution to both the problems of underproduction of 6 Li and overproduction of 7 Li in BBN. This solution involves a hypothetical massive, negatively-charged particle that would bind to the light nuclei produced in BBN. The particle gets bound to the existing nuclei after the usual BBN, and a second epoch of nucleosynthesis can occur among nuclei bound to the particles. We numerically carry out a fully dynamical BBN calculation, simultaneously solving the recombination and ionization processes of negatively-charged particles by normal and particle-bound nuclei as well as many possible nuclear reactions among them. It is confirmed that BBN in the presence of these hypothetical particles can solve the two Li abundance problems simultaneously.

Sterile neutrinos and Big Bang Nucleosynthesis in the 3 + 1 scheme

2014 ◽  
Vol 23 (03) ◽  
pp. 1450014 ◽  
Author(s):  
Mercedes Elisa Mosquera ◽  
Osvaldo Civitarese
Keyword(s):  
Distribution Function ◽  
Sterile Neutrino ◽  
Big Bang ◽  
Light Nuclei ◽  
Wilkinson Microwave Anisotropy Probe ◽  
Normalization Constant ◽  
Big Bang Nucleosynthesis ◽  
Sterile Neutrinos ◽  
Mixing Angle ◽  
Free Parameters

We study the effects of adding a sterile neutrino to three active neutrinos (3 + 1 scheme) in the calculation of primordial abundances. Taking the normalization constant (a) of the occupation factor of the sterile neutrino and the active-sterile mixing angle (ϕ) as free parameters, we calculate the neutrino distribution function and primordial abundances of light nuclei. We set constrains on these parameters by using the available data on the abundances of D, 4 He and 7 Li . Results are consistent with small values of a and ϕ. The extracted value of the baryon-to-photon ratio (ηB), which is constrained by the Wilkinson Microwave Anisotropy Probe (WMAP) value [Formula: see text], and Planck observations, depends strongly on the inclusion of the lithium data in the fit.

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.

scholarly journals THE 2H(α, γ)6LI REACTION AT LUNA AND BIG BANG NUCLEOSYNTHETIS

2013 ◽  
Vol 53 (A) ◽  
pp. 534-537 ◽  
Author(s):  
Carlo Gustavino
Keyword(s):  
Cross Section ◽  
Preliminary Data ◽  
Big Bang ◽  
Low Energy ◽  
Big Bang Nucleosynthesis ◽  
Lithium Abundance ◽  
Halo Stars ◽  
First Time ◽  
Standard Production ◽  
Production Channel

The <sup>2</sup>H(α, γ)<sup>6</sup>Li reaction is the leading process for the production of <sup>6</sup>Li in standard Big Bang Nucleosynthesis. Recent observations of lithium abundance in metal-poor halo stars suggest that there might be a 6Li plateau, similar to the well-known Spite plateau of <sup>7</sup>Li. This calls for a re-investigation of the standard production channel for <sup>6</sup>Li. As the <sup>2</sup>H(α, γ)<sup>6</sup>Li cross section drops steeply at low energy, it has never before been studied directly at Big Bang energies. For the first time the reaction has been studied directly at Big Bang energies at the LUNA accelerator. The preliminary data and their implications for Big Bang nucleosynthesis and the purported <sup>6</sup>Li problem will be shown.

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.

Research of the Ionosphere Using Equipment, Placed on Nano-Satellites. Part 1. Modeling a Vacuum Transducer

ANRI ◽  
2020 ◽  
pp. 53-63
Author(s):  
Valeriy Dreyzin ◽  
Ali Nuri Al' Kadimi
Keyword(s):  
Charged Particle ◽  
Charged Particles ◽  
Upper Atmosphere ◽  
Ion Composition ◽  
Vacuum Gauge ◽  
Approximate Design ◽  
Ionization Processes ◽  
Particle Trap ◽  
Positively Charged

The urgency of the task of studying the density and composition of the upper layers of the atmosphere with the help of tools placed in micro- and nano-satellites vehicles is substantiated. A brief description of the structure of the atmosphere is carried out, the relevance and problems of instrumental studies of the density and composition of the upper atmosphere (ionosphere) are shown. A solution to these problems is proposed by developing a combined density and ion composition sensor for the upper atmosphere layers placed on nanosatellites. An approximate design of a compact inverse-magnetron vacuum gauge transducer is proposed, on the basis of which a combined transducer of density and ion composition of the upper atmosphere is constructed by combining it with a charged particle trap. This trap not only ensures the accuracy of its readings, but also allows you to determine the concentration of negatively and positively charged particles. The simulation of ionization processes in the working area of a compact inverse magnetron vacuum gauge transducer is carried out.

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.

scholarly journals 7Be(n,p) cross section measurement for the Cosmological Lithium Problem at the n_TOF facility at CERN

2018 ◽  
Vol 184 ◽  
pp. 02004
Author(s):  
Damone Lucia Anna ◽  
N. Colonna ◽  
M. Barbagallo ◽  
M. Mastromarco ◽  
J. Andrzejewski ◽  
...  
Keyword(s):  
Cross Section ◽  
Nuclear Astrophysics ◽  
Big Bang ◽  
Big Bang Nucleosynthesis ◽  
Experimental Procedure ◽  
Cross Section Measurement ◽  
Halo Stars ◽  
Section Measurement ◽  
Primordial Abundance ◽  
The One

One of the most puzzling problems in Nuclear Astrophysics is the "Cosmological Lithium Problem", i.e the discrepancy between the primordial abundance of 7Li observed in metal poor halo stars [1], and the one predicted by Big Bang Nucleosynthesis (BBN). One of the reactions that could have an impact on the problem is 7Be(n,p)7Li. Despite of the importance of this reaction in BBN, the cross-section has never been directly measured at the energies of interest for BBN. Taking advantage of the innovative features of the second experimental area at the n_TOF facility at CERN, an accurate measurement of 7Be(n,p) cross section has been recently performed at n_TOF, with a pure 7Be target produced by implantation of a 7Be beam at ISOLDE. The experimental procedure, the setup used in the measurement and the results obtained so far will be here presented.

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