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arXiv2000

Charge Conjugation Violation in Supernovae and The Neutron Shortage for R-Process Nucelosynthesis

Core collapse supernovae are dominated by energy transport from neutrinos. Therefore, some supernova properties could depend on symetries and features of the standard model weak interactions. The cross section for neutrino capture is larger than that for antineutrino capture by one term of order the neutrino energy over the nucleon mass. This reduces the ratio of neutrons to protons in the $ν$-driven wind above a protoneutron star by approximately 20 % and may significantly hinder r-process nucleosynthesis.

astro-ph↗

arXiv1999

Charge-conjugation violating neutrino interactions in supernovae

The well known charge conjugation violating interactions in the Standard Model increase neutrino- and decrease anti-neutrino- nucleon cross sections. This impacts neutrino transport in core collapse supernovae through "recoil" corrections of order the neutrino energy $k$ over the nucleon mass $M$. All $k/M$ corrections to neutrino transport deep inside a protoneutron star are calculated from angular integrals of the Boltzmann equation. We find these corrections significantly modify neutrino currents at high temperatures. This produces a large mu and tau number for the protoneutron star and can change the ratio of neutrons to protons. In addition, the relative size of neutrino mean free paths changes. At high temperatures, the electron anti-neutrino mean free path becomes {\it longer} than that for mu or tau neutrinos.

astro-ph↗

arXiv1999

Nucleosynthesis in Supernovae

Core collapse supernovae are dominated by energy transport from neutrinos. Therefore, some supernova properties could depend on symetries and features of the standard model weak interactions. The cross section for neutrino capture is larger than that for antineutrino capture by one term of order the neutrino energy over the nucleon mass. This reduces the ratio of neutrons to protons in the $ν$-driven wind above a protoneutron star by approximately 20 % and may significantly hinder r-process nucleosynthesis.

astro-ph↗

arXiv1998

The Mu and Tau Number of Supernovae

The neutrino-nucleon cross section is slightly larger than that for $\barν-N$. Therefore, $\barν$ will escape more quickly from core collapse supernovae leaving the star $ν$ rich. A diffusion formalism is used to calculate the time evolution of the mu and tau lepton number densities. These quickly reach steady state equilibria. We estimate that a protoneutron star with a maximum temperature near 50 MeV will contain over 50 % more $ν_μ$ and $ν_τ$ than $\barν_μ$ and $\barν_τ$. Supernovae may be the only known systems with large mu and or tau lepton numbers.

hep-ph↗

arXiv1997

Cumulative Parity Violation in Supernovae

Supernovae provide a unique opportunity for large scale parity violation because they are dominated by neutrinos. We calculate the parity violating asymmetry A of neutrino emission in a strong magnetic field. We assume the neutrinos elastically scatter many times from slightly polarized neutrons. Because of multple interactions, A grows with the optical thickness of the proto-neutron star and may be much larger than previous estimates. As a result, the neutron star could recoil at a significant velocity.

astro-ph↗