The Galactic Transient Sky with Swift

TL;DR

This paper discusses Swift's capabilities for discovering and monitoring X-ray transients in the Milky Way and nearby galaxies, highlighting methods, collaborations, and specific science cases enabled by Swift's rapid response and sensitivity.

Contribution

It introduces methods for X-ray transient discovery with Swift and MAXI, and presents case studies demonstrating Swift's role in transient detection and orbital parameter determination.

Findings

Swift successfully detected and monitored MAXI J1659-152, revealing its short orbital period.

Swift observations of IGR J00569-7226 enabled detection of dips, eclipses, and orbital parameters.

Collaboration between Swift and MAXI enhances transient discovery capabilities.

Abstract

The unique capabilities of Swift that make it ideal for discovery and follow-up of Gamma-Ray bursts also makes it the idea mission for discovery and monitoring of X-ray Transients in the Milky Way and the Large and Small Magellanic Clouds. The Burst Alert Telescope allows for detection of new transient outbursts, the automated follow-up capabilities of Swift allow for rapid observation and localization of the new transient in X-rays and optical/UV bands, and Swift's rapid slewing capabilities allows for low-overhead short observations to be obtained, opening up the possibility of regular, sensitive, long term monitoring of transient outbursts that are not possible with other currently operational X-ray missions. In this paper I describe the methods of discovery of X-ray transients utilizing Swift's BAT and also collaboration with the MAXI telescope. I also detail two examples of X-ray transient science enabled by Swift: Swift discovery and monitoring observations of MAXI J1659-152, a Black Hole candidate Low Mass X-ray Binary in the Galactic Halo, which has the shortest known orbital period of any such system; and Swift monitoring of IGR J00569-7226, an edge on Be/X-ray binary that displayed a outburst in 2013 and 2014, and which monitoring by Swift allowed for detection of dips, eclipses and the determination of the orbital parameters, utilizing a measurement of doppler shifts in the pulsar period.