Constraints on Astro-unparticle Physics from SN 1987A

Abstract

SN 1987A observations have been used to place constraints on the interactions between standard model particles and unparticles. In this study we calculate the energy loss from the supernovae core through scalar, pseudo scalar, vector, pseudo vector unparticle emission from nuclear bremsstrahlung for degenerate nuclear matter interacting through one pion exchange. In order to examine the constraints on $d_{\mathcal{U}}=1$ we considered the emission of scalar, pseudo scalar, vector, pseudo vector and tensor through the pair annihilation process $e^{+}{e}^{-}\to \mathcal{U}\gamma$. In addition we have re-examined other pair annihilation processes. The most stringent bounds on the dimensionless coupling constants for $d_{\mathcal{U}}=1$ and ${\Lambda }_{\mathcal{U}}=m_Z$ are obtained from nuclear bremsstrahlung process for the pseudo scalar and pseudo-vector couplings $\left|{\lambda }_{0,1}^{\mathcal{P}}\right|\le 4\times 10^{-11}$ and for tensor interaction, the best limit on dimensionless coupling is obtained from $e^{+}{e}^{-}\to \mathcal{U}\gamma$ and we get $\left|{\lambda }^{\mathcal{T}}\right|\le 6\times 10^{-6}$.

Comments: 12 pages, 2 postscript figures