arXiv subjects

In-Saeng Suh

Publications and source records attributed to In-Saeng Suh.

40 records · Page 3Linked to original sources

arXiv1998

Weak reaction freeze-out constraints on primordial magnetic fields

We explore constraints on the strength of the primordial magnetic field based upon the weak reaction freeze-out in the early universe. We find that limits on the strength of the magnetic field found in other works are recovered simply by examining the temperature at which the rate of weak reactions drops below the rate of universal expansion ($Γ_{w} \le$ H). The temperature for which the $n/p$ ratio at freeze-out leads to acceptable helium production implies limits on the magnetic field. This simplifies the application of magnetic fields to other cosmological variants of the standard big-bang. As an illustration we also consider effects of neutrino degeneracy on the allowed limits to the primordial magnetic field.

astro-ph↗

arXiv1998

Finite temperature effects on cosmological baryon diffusion and inhomogeneous Big-Bang nucleosynthesis

We have studied finite temperature corrections to the baryon transport cross sections and diffusion coefficients. These corrections are based upon the recently computed renormalized electron mass and the modified state density due to the background thermal bath in the early universe. It is found that the optimum nucleosynthesis yields computed using our diffusion coefficients shift to longer distance scales by a factor of about 3. We also find that the minimum value of $^4 He$ abundance decreases by $ΔY_p \simeq 0.01$ while $D$ and $^7 Li$ increase. Effects of these results on constraints from primordial nucleosynthesis are discussed. In particular, we find that a large baryonic contribution to the closure density ($Ω_b h_{50}^{2} \lsim 0.4$) may be allowed in inhomogeneous models corrected for finite temperature.

astro-ph↗

arXiv1998

Axion Emissivity from the Conversion of a Neutron Star into a Strange Star

The conversion of neutron matter into strange matter in a neutron star occurs through the non-leptonic weak-interaction process. We study the energy loss of the neutron star by the emission of axions in that process. Owing to that process, the neutron star will liberate the energy which can in no way be negligible as an axion burst.

astro-ph↗

arXiv1998

Finite Temperature effects on baryon transport scattering in the early Universe

We have computed finite temperature corrections to the electron-hadron scattering cross sections. These are based upon the renormalized electron mass and the modified density of states due to the presence of a background thermal bath. It is found that the electron-hadron thermal transport scattering cross section can be much larger than the zero temperature one. In the case of electron-neutron transport scattering, we find σ_{ne}(T) / σ_{ne} (T=0) \simeq 5 at T \simeq 0.1 MeV.

astro-ph↗