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arXiv · 1804.03103

The volumetric rate of calcium-rich transients in the local universe

C. Frohmaier·M. Sullivan·K. Maguire·P. E. Nugent
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Abstract

We present a measurement of the volumetric rate of `calcium-rich' optical transients in the local universe, using a sample of three events from the Palomar Transient Factory (PTF). This measurement builds on a detailed study of the PTF transient detection efficiencies, and uses a Monte Carlo simulation of the PTF survey. We measure the volumetric rate of calcium-rich transients to be higher than previous estimates: $1.21^{+1.13}_{-0.39}\times10^{-5}$ events yr$^{-1}$ Mpc$^{-3}$. This is equivalent to 33-94% of the local volumetric type Ia supernova rate. This calcium-rich transient rate is sufficient to reproduce the observed calcium abundances in galaxy clusters, assuming an asymptotic calcium yield per calcium-rich event of ~0.05$\mathrm{M}_{\odot}$. We also study the PTF detection efficiency of these transients as a function of position within their candidate host galaxies. We confirm as a real physical effect previous results that suggest calcium-rich transients prefer large physical offsets from their host galaxies.

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C. Frohmaier, M. Sullivan, K. Maguire, P. E. Nugent. 2018-04-09. The volumetric rate of calcium-rich transients in the local universe. https://doi.org/10.3847/1538-4357%2Faabc0b

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