Proposal Details - 1120029
Regular INTEGRAL monitoring of the Crab (Kuulkers)

Proposal Abstract

For as long as X-ray astronomy exists, X-ray (and gamma-ray) astronomers consider the Crab supernova remnant to be a steady standard candle suitable as a calibration source. INTEGRAL has been observing the Crab, for mainly calibration purposes, only about twice per year, for a total of about 4 revolutions per AO. Further observations have been sparse, and only every now and then it was in the field of view during a few ad-hoc observations of relatively nearby sources. It is proposed to monitor the Crab more frequently, on a regular basis. The objectives are two-fold: 1) monitor and seek for accompanying flares which have been seen at >100 MeV by Fermi and Agile, 2) improve on the (cross-) calibration of the INTEGRAL instruments, as well as with other high-energy instruments. It is proposed to look at the Crab every 4th revolution with a single standard 5x5 pattern for 45 ksec. The data will be made public immediately.

Observation Strategy (Recommended by TAC)

Total of 540 ks centered on RA, Dec (J2000.0, in degrees) = 83.633, 22.014 (l, b = 184.557, -5.784 degrees). The time will be split into 12 fixed time observations of 45 ks each (a standard 5x5 dither pattern per observation will be used, where each individual pointing lasts 1800 sec). To be done approximately every 4th INTEGRAL orbit when Crab is visible.

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 100, 300 and 500 ksec contour.