Are carbon deflagration supernovae triggered by dark matter ?

TL;DR

This work investigates whether dark matter interactions, notably collisions between primordial black holes and white dwarfs, could trigger Type Ia supernovae in galactic centers. It combines rate estimates from collision-related triggering and gravitational focusing with radial-distribution modeling in an NFW dark matter halo, benchmarking against the observed SN Ia rate and Millennium TAO data. The findings suggest that a dark matter fraction of order a few tenths can reproduce the observed rates within current constraints, and that DM-triggered SNe could exhibit a more central concentration than stellar light, though galaxy-to-galaxy variance and selection effects temper the conclusion. Upcoming Rubin Observatory data, with millions of SNe and host-galaxy profiles, will decisively test the DM-triggering hypothesis and tighten constraints on dark matter density in galactic cores.

Abstract

Collisions between stellar remnants and dark matter in the Galactic bulge are frequent, and the kinetic energy of a primordial black hole incident on a white dwarf, if it is all thermalized, will raise the degenerate core's temperature, by at least a degree in the case of a lunar mass black hole. This is an underestimate in two ways: the specific heat is less than 3k/2 per particle, and the incoming object is accelerated by gravitational focusing. Detailed physical models have recently been made of this triggering event. Present observational data are equivocal as to whether the radial distribution of type Ia supernovae in galaxies follows the starlight in the galaxies, or is more concentrated towards the center, as collisional triggering would suggest. But future samples of millions of supernovae from the Rubin telescope will change that.

Figures (4)

• Figure 1: Radial distribution of SNeIa in the Dark Energy Survey (in red). The green curve is the expectation for exponential disks and the blue curve for elliptical galaxies. These have not been normalised to the data. The other two curves are for DM triggered SNe, and these have been normalized to the same total number of SNe, excluding the first, central bin, which is anomalous, and is conceivably a selection effect of some SN being masked by the nucleus.
• Figure 2: The top two panels are the radial distribution of SNeIa scaled to remove distance dependence as described in the text, using the RC3 diameter D$_{25}$ (de Vaucouleurs et al. 1976). The solid histogram (upper left) has been corrected for (1+z)$^4$ surface brightness dimming, and the dotted histogram has not. The difference is small for these low z galaxies. The lower two panels use the total magnitude K band radius from the 2MASS survey. The shaded red histogram is the galaxies in Table 2 shown separately. In the bottom right hand plot they have been added in. In general the slope of these histograms is shallower than the expectation from the stellar light (the green curves and lines).
• Figure A1: Ratio of 2MASS isophotal diameters to RC3 D$_{25}$ diameters. There is no noticeable difference between the black z $<$ 0.02 subsample and the green z $>$ 0.02 one.
• Figure A2: Raw SN radii divided by 2MASS radius (red histogram). The solid black histogram has been corrected for surface brightness dimming.