Search for Gamma-Ray Emission from Local Primordial Black Holes with the Fermi Large Area Telescope
Authors: Ackermann M. , Atwood W. B. , Baldini L. , Ballet J. , Barbiellini G. , Bastieri D. , Bellazzini R. , Berenji B. , Bissaldi E. , Blandford R. D. , Bloom E. D. , Bonino R. , Bottacini E. , Bregeon J. , Bruel P. , Buehler R. , Cameron R. A. , Caputo R. , Caraveo P. A. , Cavazzuti E. , Charles E. , Chekhtman A. , Cheung C. C. , Chiaro G. , Ciprini S. , Cohen-Tanugi J. , Conrad J. , Costantin D. , D’Ammando F. , Palma F. de , Digel S. W. , Lalla N. Di , Mauro M. Di , Venere L. Di , Favuzzi C. , Fegan S. J. , Focke W. B. , Franckowiak A. , Fukazawa Y. , Funk S. , Fusco P. , Gargano F. , Gasparrini D. , Giglietto N. , Giordano F. , Giroletti M. , Green D. , Grenier I. A. , Guillemot L. , Guiriec S. , Horan D. , Jóhannesson G. , Johnson C. , Kensei S. , Kocevski D. , Kuss M. , Larsson S. , Latronico L. , Li J. , Longo F. , Loparco F. , Lovellette M. N. , Lubrano P. , Magill J. D. , Maldera S. , Malyshev D. , Manfreda A. , Mazziotta M. N. , McEnery J. E. , Meyer M. , Michelson P. F. , Mitthumsiri W. , Mizuno T. , Monzani M. E. , Moretti E. , Morselli A. , Moskalenko I. V. , Negro M. , Nuss E. , Ojha R. , Omodei N. , Orienti M. , Orlando E. , Ormes J. F. , Palatiello M. , Paliya V. S. , Paneque D. , Persic M. , Pesce-Rollins M. , Piron F. , Principe G. , Rainò S. , Rando R. , Razzano M. , Razzaque S. , Reimer A. , Reimer O. , Ritz S. , Sánchez-Conde M. , Sgrò C. , Siskind E. J. , Spada F. , Spandre G. , Spinelli P. , Suson D. J. , Tajima H. , Thayer J. G. , Thayer J. B. , Torres D. F. , Tosti G. , Troja E. , Valverde J. , Vianello G. , Wood K. , Wood M. , Zaharijas G. 
Published: April 2018

Black holes with masses below approximately 1015 g are expected to emit gamma-rays with energies above a few tens of MeV, which can be detected by the Fermi Large Area Telescope (LAT). Although black holes with these masses cannot be formed as a result of stellar evolution, they may have formed in the early universe and are therefore called primordial black holes (PBHs). Previous searches for PBHs have focused on either short-timescale bursts or the contribution of PBHs to the isotropic gamma-ray emission. We show that, in cases of individual PBHs, the Fermi-LAT is most sensitive to PBHs with temperatures above approximately 16 GeV and masses 6 × 1011 g, which it can detect out to a distance of about 0.03 pc. These PBHs have a remaining lifetime of months to years at the start of the Fermi mission. They would appear as potentially moving point sources with gamma-ray emission that become spectrally harder and brighter with time until the PBH completely evaporates. In this paper, we develop a new algorithm to detect the proper motion of gamma-ray point sources, and apply it to 318 unassociated point sources at a high galactic latitude in the third Fermi-LAT source catalog. None of the unassociated point sources with spectra consistent with PBH evaporation show significant proper motion. Using the nondetection of PBH candidates, we derive a 99% confidence limit on the PBH evaporation rate in the vicinity of Earth,

ρ

˙

PBH

<
7.2
×

10

3

pc

−
3

yr

−
1

. This limit is similar to the limits obtained with ground-based gamma-ray observatories.