Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 18555

GRB 151027A: the missing GeV component
2015-11-03T18:21:32Z (9 years ago)
Remo Rufinni at ICRA <>
R. Ruffini, Y. Aimuratov, U. Barres, R. Belvedere, C.L. Bianco, M. Enderli, M. Kovacevic, R. Moradi, M. Muccino, A. Penacchioni, G.B. Pisani, J.A. Rueda, Y. Wang report:

From its overlapping [1] with GRB 090618, the prototype of binary-driven hypernovae (BdHNe), we can assert that this GRB belongs to the class of long GRBs originating in a binary system composed of a carbon-oxygen core and a companion neutron star (Rueda & Ruffini, 2012; Fryer et al. 2014).

At the redshift of z=0.81 (Perley et al, GCN 18487) the isotropic energy is Eiso ~ 4x10^(52) erg and the rest-frame spectral peak energy is Ep,i ~ 615 keV (Toelge et al., GCN 18492). A SN should appear after 13-15 days in rest-frame, namely between November 19th and November 23rd.

The exceptional feature of GRB 151027A is that, even if it belongs to the BdHN class, there is no high energy emission associated as of today although it was in the Fermi-LAT field of view (Toelge et al., GCN 18492). If confirmed this can be of support to probe the angular distribution of the high energy emission. Additional data in all wavelengths are requested for this most peculiar source.

Looking for U.S. government information and services? Visit