Constraints on primordial black holes with extended mass functions

Abstract

Constraints on primordial black holes in the range 10 −18 M to 10 3 M are reevaluated for a general class of extended mass functions. Whereas previous work has assumed that PBHs are produced with one single mass, instead there is expected to be a range of masses even in the case of production from a single mechanism; constraints therefore change from previous literature. Although tightly constrained in the majority of cases, it is shown that, even under conservative assumptions, primordial black holes in the mass range 10 −10 M to 10 −8 M could still constitute the entirety of the dark matter. This stresses both the importance for a comprehensive reevaluation of all respective constraints that have previously been evaluated only for a monochromatic mass function, and the need to obtain more constraints in the allowed mass range.

Astrophysical uncertainties on stellar microlensing constraints on multisolar mass primordial black hole dark matter

“…Taken at face value together they exclude PBHs with 10 −7 < M/M < 10 5 making up all of the dark matter [3,26,27,29]. However the microlensing differential event rate, and hence the resulting constraints on compact objects, depend on their density and velocity distribution along the line of sight to the LMC.…”

“…Ref. [27] subsequently studied the full range of possible PBH masses, and found a window around (10 −10 − 10 −8 )M where PBHs with a quasi-log-normal mass function could make up all of the DM. However high-cadence microlensing observations of M31 [28] have subsequently placed tight constraints on this mass range.…”

Primordial Black Holes as a Dark Matter Candidate Are Severely Constrained by the Galactic Center 511 keVγ-Ray Line

“…Various inflationary models also predict an extended mass distribution of PBHs [5,[74][75][76][77][78][79]. It is important to study these models in detail as the possibility of whether PBHs contribute significantly to the dark matter density depend substantially on the underlying mass distri-bution [54,[80][81][82][83]. Traditionally, the limits on the PBH density were presented only for monochromatic mass distributions, however, there has been recent interest into converting these limits for various extended mass distributions of PBHs.…”

Disentangling the Potential Dark Matter Origin of LIGO’s Black Holes

“…If the Eri II and Segue I constraints are relaxed, power-law, lognormal, and critical collapse mass functions could allow for 100% PBH dark matter for two small windows surrounding 5 × 10 −16 M and 2 × 10 −14 M as well as for 25 − 100M , though Carr finds that no more than 10% can be accounted for by these mass functions when the dwarf galaxy constraints are considered (Carr et al 2017). The first two windows (as well as the one Kühnel & Freese (2017) describe) are unreachable by LIGO, and the ∼ 25 − 100M interval could yield LIGO detection rates inconsistent with the works of Sasaki et al (2016) and Eroshenko (2016). Additionally, new constraints by Gaggero et al (2017) place similar limits to Eri II and Segue I on PBH DM in the window 25 − 100M using observations with independent systematics, making this window less likely to contain all of the dark matter.…”

“…Quasi log-normal forms have been extensively analyzed by Green (2016) and Kühnel & Freese (2017), with the former ruling out this family of mass functions as a source of all DM for 10 −7 M < M < 10 5 M while the latter showed that for a narrow window where 10 −10 M < M < 10 −8 M this remains a possibility.…”