Feasibility of a Small, Rapid Optical-to-IR Response, Next Generation Gamma Ray Burst Mission

TL;DR

This paper evaluates the feasibility of a small, fast-response gamma-ray burst observatory capable of rapid optical/IR detection, showing it can detect a significant number of GRBs annually with modest-sized instruments.

Contribution

It demonstrates the potential for a compact, rapid-response GRB observatory with realistic detection rates based on existing data and new capabilities.

Findings

Detects approximately 27 GRBs per year with a scaled-down Swift-like orbit.

Optical detection of about 23% of X-ray localized GRBs with a 10 cm instrument.

Rapid optical/IR response (~1 s) enhances scientific opportunities.

Abstract

We present motivations for and study feasibility of a small, rapid optical to IR response gamma ray burst (GRB) space observatory. By analyzing existing GRB data, we give realistic detection rates for X-ray and optical/IR instruments of modest size under actual flight conditions. Given new capabilities of fast optical/IR response (about 1 s to target) and simultaneous multi-band imaging, such an observatory can have a reasonable event rate, likely leading to new science. Requiring a Swift-like orbit, duty cycle, and observing constraints, a Swift-BAT scaled down to 190 square cm of detector area would still detect and locate about 27 GRB per yr. for a trigger threshold of 6.5 sigma. About 23 percent of X-ray located GRB would be detected optically for a 10 cm diameter instrument (about 6 per yr. for the 6.5 sigma X-ray trigger).