62 citations · 1.3k across the 66 of their papers we have counts for
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Effect of Magnetic Field Dissipation on Primordial Li Abundance
Yini Lu, Motohiko Kusakabe
The dissipation effects of primordial magnetic fields on the primordial elemental abundances were investigated. When a magnetic field reconnects, its energy is converted to the kin…
Distribution function of nuclei from scattering in the presence of a strong primordial magnetic field
Motohiko Kusakabe, Atul Kedia, Grant J. Mathews +1
The amplitude of the primordial magnetic field (PMF) is constrained from observational limits on primordial nuclear abundances. Within this constraint, it is possible that nuclear…
Impacts of Hawking Radiation from Primordial Black Holes in Critical Collapse Model on the Light Element Abundances
Yudong Luo, Chao Chen, Motohiko Kusakabe +1
We study the photodisintegration process triggered by the nonthermal electromagnetic Hawking radiation from primordial black holes (PBHs) in critical collapse model. We consider th…
Screening corrections to Electron Capture Rates and resulting constraints on Primordial Magnetic Fields
Yudong Luo, Michael A. Famiano, Toshitaka Kajino +2
We explore screening effects arising from a relativistic magnetized plasma with applications to Big Bang nucleosynthesis (BBN). %Specifically, due to their small magnetic moments,…
Cosmological Solutions to the Lithium Problem
G. J. Mathews, A. Kedia, N. Sasankan +6
The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at a…
Roles of BeLi resonances in big bang nucleosynthesis with time-dependent quark mass and Li reduction by a heavy quark mass
Kanji Mori, Motohiko Kusakabe
Big bang nucleosynthesis (BBN) has been used as a probe of beyond-standard physics in the early Universe, which includes a time-dependent quark mass m_q. We investigate effects of…
Big Bang Nucleosynthesis with an Inhomogeneous Primordial Magnetic Field Strength
Yudong Luo, Toshitaka Kajino, Motohiko Kusakabe +1
We investigate the effect on the Big Bang Nucleosynthesis (BBN) from the presence of a stochastic primordial magnetic field (PMF) whose strength is spatially inhomogeneous. We assu…
Relativistic Electron Scattering and Big Bang Nucleosynthesis
Nishanth Sasankan, Atul Kedia, Motohiko Kusakabe +1
This paper is superseded by Arxiv:1911.07334. Big-bang nucleosynthesis (BBN) is a valuable tool to constrain the physics of the early universe and is the only probe of the radiatio…
On the relative velocity distribution for general statistics and an application to big-bang nucleosynthesis under Tsallis statistics
Motohiko Kusakabe, Toshitaka Kajino, Grant J. Mathews +1
The distribution function of the relative velocity in a two-body reaction of nonrelativistic uncorrelated particles is derived for general cases of given distribution functions of…
Review on Effects of Long-lived Negatively Charged Massive Particles on Big Bang Nucleosynthesis
Motohiko Kusakabe, Grant. J. Mathews, Toshitaka Kajino +1
We review important reactions in the big bang nucleosynthesis (BBN) model involving a long-lived negatively charged massive particle, , which is much heavier than nucleons. Th…
Introduction to Big Bang Nucleosynthesis and Modern Cosmology
Grant J. Mathews, Motohiko Kusakabe, Toshitaka Kajino
Primordial nucleosynthesis remains as one of the pillars of modern cosmology. It is the testing ground upon which many cosmological models must ultimately rest. It is our only prob…
Revised Uncertainties in Big Bang Nucleosynthesis
Michael Foley, Nishanth Sasankan, Motohiko Kusakabe +1
Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2σ level for the abun…
Limits on Brane-World and Particle Dark Radiation from Big Bang Nucleosynthesis and the CMB
Nishanth Sasankan, Mayukh. R. Gangopadhyay, Grant. J. Mathews +1
The term dark radiation is used both to describe a noninteracting neutrino species and as a correction to the Friedmann Equation in the simplest five-dimensional RS-II brane-world…
New observational limits on dark radiation in brane-world cosmology
Nishanth Sasankan, Mayukh R. Gangopadhyay, Grant J. Mathews +1
A dark radiation term arises as a correction to the energy momentum tensor in the simplest five-dimensional RS-II brane-world cosmology. In this paper we revisit the constraints on…
Constraints on modified Gauss-Bonnet gravity during big bang nucleosynthesis
Motohiko Kusakabe, Seoktae Koh, K. S. Kim +1
The modified gravity is considered to be one of possible explanations of the accelerated expansions of the present and the early universe. We study effects of the modified gravity…
Corrected constraints on big bang nucleosynthesis in a modified gravity model of
Motohiko Kusakabe, Seoktae Koh, K. S. Kim +1
Big bang nucleosynthesis in a modified gravity model of is investigated. The only free parameter of the model is a power-law index . We find cosmological solut…
Cosmological solutions to the Lithium problem: Big-bang nucleosynthesis with photon cooling, -particle decay and a primordial magnetic field
Dai G. Yamazaki, Motohiko Kusakabe, Toshitaka Kajino +2
The Li abundance calculated in BBN with the baryon-to-photon ratio fixed from fits to the CMB power spectrum is inconsistent with the observed lithium abundances on the surface…
General limit on the relation between abundances of D and Li in big bang nucleosynthesis with nucleon injections
Motohiko Kusakabe, Myung-Ki Cheoun, K. S. Kim
The injections of energetic hadrons could have occurred in the early universe by decays of hypothetical long-lived exotic particles. The injections induce the showers of nonthermal…
Chemical separation of primordial Li during structure formation caused by nanogauss magnetic field
Motohiko Kusakabe, Masahiro Kawasaki
During the structure formation, charged and neutral chemical species may have separated from each other at the gravitational contraction in primordial magnetic field (PMF). A gradi…
Effects of Long-lived 10 MeV Scale Sterile Neutrino on Primordial Elemental Abundances and Effective Neutrino Number
Hiroyuki Ishida, Motohiko Kusakabe, Hiroshi Okada
The primordial lithium abundance inferred from observations of metal-poor stars is ~3 times smaller than the theoretical value in standard big bang nucleosynthesis (BBN) model. We…
Revised Big Bang Nucleosynthesis with long-lived negatively charged massive particles: updated recombination rates, primordial 9Be nucleosynthesis, and impact of new 6Li limits
Motohiko Kusakabe, K. S. Kim, Myung-Ki Cheoun +3
We extensively reanalyze effects of a long-lived negatively charged massive particle, X-, on big bang nucleosynthesis (BBN). The BBN model with an X- particle was originally motiva…
7Be charge exchange between 7Be3+ ion and exotic long-lived negatively charged massive particle in big bang nucleosynthesis
Motohiko Kusakabe, K. S. Kim, Myung-Ki Cheoun +2
The existence of an exotic long-lived negatively charged massive particle, i.e., X-, during big bang nucleosynthesis can affect primordial light element abundances. Especially, the…
A Big-Bang Nucleosynthesis Limit on the Neutral Fermion Decays into Neutrinos
Motohiko Kusakabe, A. B. Balantekin, Toshitaka Kajino +1
Using the primordial helium abundance, an upper limit to the magnetic moments for Dirac neutrinos had been provided by imposing restrictions on the number of the additional helicit…
Effects of power law primordial magnetic field on big bang nucleosynthesis
Dai G. Yamazaki, Motohiko Kusakabe
Big bang nucleosynthesis (BBN) is affected by the energy density of a primordial magnetic field (PMF). For an easy derivation of constraints on models for PMF generations, we assum…