# Invisibles 2021 Workshop

May 31, 2021 to June 4, 2021
Online

## Mergers as a Probe of Particle Dark Matter

Jun 2, 2021, 5:54 PM
6m
Online

#### Online

PhD forum talk + poster

### Speaker

Anupam Ray (Tata Institute of Fundamental Research, India)

### Description

Unusual masses of black holes being discovered by gravitational wave experiments pose fundamental questions about the origin of these black holes. More interestingly, black holes with masses smaller than the Chandrasekhar limit ($\sim$ 1.4 $M_{\odot}$) are essentially impossible to produce through any standard stellar evolution. Primordial black holes, with fine-tuned parameters and with no well-established formation mechanisms, are the most discussed explanation of these objects. In this talk, I will discuss a simple production channel of these low mass black holes. Particle dark matter with no antiparticle counterpart, owing to their interaction with stellar nuclei, can catastrophically accumulate inside compact stars and eventually transmute them to sub-Chandrasekhar mass black holes, ordinarily forbidden by the Chandrasekhar limit. I will point out several avenues to test the origin of these low mass black holes, concentrating on the cosmic evolution of the binary merger rate. I will show that binary merger rates especially at high redshift are distinctively different for primordial and transmuted black holes, and measurement of these merger rates by the imminent gravitational wave detectors can conclusively test the origin of low mass black holes.

 arXiv number (if applicable) 2009.02

### Primary author

Anupam Ray (Tata Institute of Fundamental Research, India)

### Co-authors

Basudeb Dasgupta (Tata Institute of Fundamental Research, Mumbai) Dr Ranjan Laha (Indian Institute of science (IN))

### Presentation materials

 Anupam_Invisibles_poster.pdf Anupam_Invisibles_talk.pdf