English

Constraints on the cosmic string loop collapse fraction from Primordial Black Holes

Cosmology and Nongalactic Astrophysics 2020-07-01 v2 High Energy Physics - Phenomenology

Abstract

A small fraction, ff, of cosmic string loops can collapse to form Primordial Black Holes (PBHs). Constraints on the abundance of PBHs can therefore be used to constrain ff. We update these calculations, taking into account the PBH extended mass function, and find f<1031(Gμ/c2)3/2f < 10^{-31} (G \mu/ c^2)^{-3/2}. This is roughly two orders of magnitude tighter than previous constraints. The improvement from the tighter constraints on the abundance of PBHs is partly off-set by refinements to the theoretical calculation of the cosmic string loop formation rate.

Keywords

Cite

@article{arxiv.1911.12658,
  title  = {Constraints on the cosmic string loop collapse fraction from Primordial Black Holes},
  author = {Chloe James-Turner and Danton P. B. Weil and Anne M. Green and Edmund J. Copeland},
  journal= {arXiv preprint arXiv:1911.12658},
  year   = {2020}
}

Comments

5 pages, v2: takes into account only a fraction of string network energy goes into long loops, constraints consequently weakened by one order of magnitude (thank you to referee for pointing this out) + other minor changes