* Astronomy

Maxima of the variable star AX Persei on the 1st March 2015.

The variable star AX Persei is at maxima on the 19th April, 2013.

Magnitude range: 9.4 - 13.6
Period: 680.6days 
Type: Z Andromedae 

Position (J2000): R.A. 01 36 22.70 | Dec. +54° 5' 02.0''

Google earth file: AX Persei.kmz (1kb, kmz)

 

Title: Formation of a disk structure in the symbiotic binary AX Per during its 2007-10 precursor-type activity
Authors: A. Skopal, T. N. Tarasova, Z. Cariková, F. Castellani, G. Cherini, S. Dallaporta, A. Frigo, C. Marangoni, S. Moretti, U. Munari, G. L. Righetti, A. Siviero, S. Tomaselli, A. Vagnozzi, P. Valisa

AX Per is an eclipsing symbiotic binary. During active phases, deep narrow minima are observed in its light curve, and the ionisation structure in the binary changes significantly. From 2007.5, AX Per entered a new active phase. It was connected with a significant enhancement of the hot star wind. Simultaneously, we identified a variable optically thick warm (Teff ~ 6000 K) source that contributes markedly to the composite spectrum. The source was located at the hot star's equator and has the form of a flared disk, whose outer rim simulates the warm photosphere. The formation of the neutral disk-like zone around the accretor during the active phase was connected with its enhanced wind. We suggested that this connection represents a common origin of the warm pseudophotospheres that are indicated during the active phases of symbiotic stars.

Read more  (257kb, PDF)