FIVE CONCENTRIC RINGS AROUND THE BLACK HOLE V404CYG

Image Credit: G. Vasilopoulos & M. Petropoulou.
RGB image of the X-ray dust scattered rings observed by Swift/XRT. The Swift/XRT field-of-view is enclosed by the green circle, while a white circle of radius 9′ is overplotted for guiding the eye. The black hole is located at the center of the rings.

First detection of X-ray dust scattered rings from the Galactic low mass X-ray binary V404 Cyg. The observation of the system with Swift/XRT on June 30 2015 revealed the presence of five concentric ring-like structures centred at the position of V404 Cyg.

A low-mass X-ray binary (LMXB) is a binary star where one of the components is either a black hole or neutron star. The X-rays are produced by matter falling from the donor star that usually is a relatively normal star less massive than the compact object.
V404 Cyg is an X-ray transient source with three confirmed historical outbursts in 1936, 1958 and 1989. The black hole has an estimated mass of ~12 solar mass. The donor star has a mass of ∼1 solar mass and it is a late type G or early type K star (it is similar to our sun).

The study of the rings can provide information for the properties of the interstellar medium and the dust distribution in the direction of the black hole.

► Read more>>
http://arxiv.org/pdf/1511.00932v1.pdf
http://mnras.oxfordjournals.org/content/455/4/4426.abstract

► Image Credit:
G. Vasilopoulos & M. Petropoulou

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