TY - JOUR
T1 - Rapid, machine-learned resource allocation
T2 - Application to high-redshift gamma-ray burst follow-up
AU - Morgan, A. N.
AU - Long, James
AU - Richards, Joseph W.
AU - Broderick, Tamara
AU - Butler, Nathaniel
AU - Bloom, Joshua S.
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2012/2/20
Y1 - 2012/2/20
N2 - As the number of observed gamma-ray bursts (GRBs) continues to grow, follow-up resources need to be used more efficiently in order to maximize science output from limited telescope time. As such, it is becoming increasingly important to rapidly identify bursts of interest as soon as possible after the event, before the afterglows fade beyond detectability. Studying the most distant (highest redshift) events, for instance, remains a primary goal for many in the field. Here, we present our Random Forest Automated Triage Estimator for GRB redshifts (RATE GRB-z ) for rapid identification of high-redshift candidates using early-time metrics from the three telescopes onboard Swift. While the basic RATE methodology is generalizable to a number of resource allocation problems, here we demonstrate its utility for telescope-constrained follow-up efforts with the primary goal to identify and study high-z GRBs. For each new GRB, RATE GRB-z provides a recommendation - based on the available telescope time - of whether the event warrants additional follow-up resources. We train RATE GRB-z using a set consisting of 135 Swift bursts with known redshifts, only 18 of which are z > 4. Cross-validated performance metrics on these training data suggest that 56% of high-z bursts can be captured from following up the top 20% of the ranked candidates, and 84% of high-z bursts are identified after following up the top 40% of candidates. We further use the method to rank 200 + Swift bursts with unknown redshifts according to their likelihood of being high-z.
AB - As the number of observed gamma-ray bursts (GRBs) continues to grow, follow-up resources need to be used more efficiently in order to maximize science output from limited telescope time. As such, it is becoming increasingly important to rapidly identify bursts of interest as soon as possible after the event, before the afterglows fade beyond detectability. Studying the most distant (highest redshift) events, for instance, remains a primary goal for many in the field. Here, we present our Random Forest Automated Triage Estimator for GRB redshifts (RATE GRB-z ) for rapid identification of high-redshift candidates using early-time metrics from the three telescopes onboard Swift. While the basic RATE methodology is generalizable to a number of resource allocation problems, here we demonstrate its utility for telescope-constrained follow-up efforts with the primary goal to identify and study high-z GRBs. For each new GRB, RATE GRB-z provides a recommendation - based on the available telescope time - of whether the event warrants additional follow-up resources. We train RATE GRB-z using a set consisting of 135 Swift bursts with known redshifts, only 18 of which are z > 4. Cross-validated performance metrics on these training data suggest that 56% of high-z bursts can be captured from following up the top 20% of the ranked candidates, and 84% of high-z bursts are identified after following up the top 40% of candidates. We further use the method to rank 200 + Swift bursts with unknown redshifts according to their likelihood of being high-z.
KW - gamma-ray burst: general
KW - methods: data analysis
KW - methods: statistical
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U2 - 10.1088/0004-637X/746/2/170
DO - 10.1088/0004-637X/746/2/170
M3 - Article
AN - SCOPUS:84856843981
VL - 746
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 2
M1 - 170
ER -