Awakening the BALROG: bayesian location reconstruction of GRBs

File Description SizeFormat 
paper_accepted.pdfAccepted version6.1 MBAdobe PDFView/Open
Title: Awakening the BALROG: bayesian location reconstruction of GRBs
Authors: Burgess, JM
Yu, HF
Greiner, J
Mortlock, DJ
Item Type: Journal Article
Abstract: The accurate spatial location of gamma-ray bursts (GRBs) is crucial for both accurately characterizing their spectra and follow-up observations by other instruments. The Fermi Gamma-ray Burst Monitor (GBM) has the largest field of view for detecting GRBs as it views the entire unocculted sky, but as a non-imaging instrument it relies on the relative count rates observed in each of its 14 detectors to localize transients. Improving its ability to accurately locate GRBs and other transients is vital to the paradigm of multimessenger astronomy, including the electromagnetic follow-up of gravitational wave signals. Here we present the BAyesian Location Reconstruction Of GRBs (balrog) method for localizing and characterizing GBM transients. Our approach eliminates the systematics of previous approaches by simultaneously fitting for the location and spectrum of a source. It also correctly incorporates the uncertainties in the location of a transient into the spectral parameters and produces reliable positional uncertainties for both well-localized sources and those for which the GBM data cannot effectively constrain the position. While computationally expensive, balrog can be implemented to enable quick follow-up of all GBM transient signals. Also, we identify possible response problems that require attention and caution when using standard, public GBM detector response matrices. Finally, we examine the effects of including the uncertainty in location on the spectral parameters of GRB 080916C. We find that spectral parameters change and no extra components are required when these effects are included in contrast to when we use a fixed location. This finding has the potential to alter both the GRB spectral catalogues and the reported spectral composition of some well-known GRBs.
Issue Date: 1-May-2018
Date of Acceptance: 1-Nov-2017
ISSN: 0035-8711
Publisher: Oxford University Press (OUP)
Start Page: 1427
End Page: 1444
Journal / Book Title: Monthly Notices of the Royal Astronomical Society
Volume: 476
Issue: 2
Copyright Statement: ©2017 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society
Sponsor/Funder: Imperial College Trust
European Commission
Science and Technology Facilities Council
Science and Technology Facilities Council (STFC)
Funder's Grant Number: N/A
Keywords: Science & Technology
Physical Sciences
Astronomy & Astrophysics
methods: data analysis
methods: statistical
gamma-ray burst: general
0201 Astronomical And Space Sciences
Publication Status: Published
Online Publication Date: 2017-11-28
Appears in Collections:Physics
Faculty of Natural Sciences

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commonsx