Proposal Details - 1020017
ISA: INTEGRAL Spiral Arms Monitoring Program (Bodaghee)

Proposal Abstract

We propose to continue our Key Programme that consists of high-cadence monitoring of the inner spiral arms of the Galaxy with INTEGRAL paired with ToO observations of new transients with XMM-Newton and Swift. While these regions are already exposed thanks to the Galactic Plane Scans (GPS), many transients are being missed because of month-long gaps between scans of any particular region. The INTEGRAL Spiral Arms (ISA) program (25.6 ks per spacecraft revolution during visibility periods, for a total of 1.2 Ms) complements the successful Galactic Bulge (GB) program by extending the monitored region of the Galaxy to the Inner Perseus/Norma Arm tangents on one side of the GB, and the Scutum/Sagittarius Arms on the other. These fields feature a high density of obscured high-mass X-ray binaries (HMXBs), including Supergiant Fast X-ray Transients (SFXTs), as well as other hard X-ray emitting sources (e.g. microquasars, low-mass X-ray binaries, and magnetars) that INTEGRAL is well-suited to finding thanks to its large field of view and angular resolution at high energies even in crowded regions of the sky. Mosaic images and source light curves in 2 energy bands for ISGRI and JEM-X are being provided to the community1 permitting rapid dissemination of results which enable prompt follow-up of interesting events. The ISA project represents the cornerstone of our ongoing study of transient and variable hard X-ray populations in the Milky Way.

Observation Strategy (Recommended by TAC)

During the visibility periods, the inner-arm regions on opposing sides of the Galactic bulge will be observed once per spacecraft revolution: i.e., the Perseus/Norma Arms around (l, b) = (337.5, 0 degrees) and the Scutum/Sagittarius Arms around (l, b) = (22.5,0 degrees). One standard hexagonal pattern (12.6 ks) per arm per INTEGRAL revolution is to be done, up to a total of 600 ks. At the end of each individual observation, the center of the hexagonal pattern is offset by 1 degree in order to overlap JEM-X and ISGRI pointings and help reduce imaging systematics. 3 XMM-Newton TOO observations of distinct new transients with an exposure time of 10 ks each are granted.

Proposal grade: A

Data Rights (Recommended by TAC)

All data are public.

Exposure Map

The exposure maps are in galactic coordinates using the Aitoff projection and units of seconds, and the colour scale is indicated at the bottom. The green lines provide the 50, 200, 350, 500 and 650 ksec contour.