Proposal Details - 0920014
Hard X-ray spectroscopy of two ultraluminous X-ray sources and a low-luminosity AGN (Sazonov)

Proposal Abstract

The nature of ultra-luminous X-ray sources (ULXs) remains unknown. One does not know whether they host stellar- or intermediate-mass black holes, nor does one have a clear understanding of the accretion process. Similarly poorly studied is accretion onto supermassive black holes in low-luminosity active galactic nuclei (LLAGN). To address these problems, high-sensitivity observations at energies above 10 keV are needed. It is proposed to add 2+2 Ms of exposure with INTEGRAL in AO9 and AO10 to a 4 Ms exposure to be accumulated in AO7 and AO8 in a unique field where two of the brightest ULXs, M82 X-1 and Holmberg IX X-1, and one of the brightest LLAGN, M81, are located. One will measure the spectra of these sources in the 3-100 keV energy band and study their spectral variability.

Observation Strategy (Recommended by TAC)

Total of 2 Ms in the standard 5x5 dithering mode centered on RA, Dec = 148.958, 69.679 (l, b = 141.412, 40.564).

Proposal grade: B

Data Rights (Recommended by TAC)

The TAC granted data rights on: M81, M82 X-1 and Holmberg IX X-1.

Consult the Data Rights policy for more information on Russian Federation proposals.

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.