X Persei - correlation between H-alpha and X-ray variability
ATel #11373; R. Zamanov, K. A. Stoyanov, N. Petrov, Y. Nikolov (Institute of Astronomy and NAO, Bulgarian Academy of Sciences, Bulgaria), D. Marchev (Shumen University, Bulgaria), U. Wolter (Hamburg, Germany)
on 1 Mar 2018; 08:53 UT
Credential Certification: Kiril Stoyanov (firstname.lastname@example.org)
Subjects: Optical, X-ray, Binary, Neutron Star
We performed H-alpha spectroscopic observations of the Be/X-ray binary X Per,
optical counterpart of the slow X-ray pulsar 4U 0352+30, using the 2.0m telescope of the Rozhen National Astronomical Observatory,
Bulgaria and the 1.2m TIGRE telescope located in Mexico.
Some of the measured equivalent widths (EW(Ha)) of the H-alpha emission line are:
JD 2457383.34 -33.02Å
JD 2457418.30 -30.28Å
JD 2457654.57 -29.80Å
JD 2457694.54 -33.28Å
JD 2457734.38 -30.88Å
JD 2457830.29 -31.87Å
JD 2458095.22 -24.11Å
JD 2458110.54 -22.35Å
JD 2458120.23 -20.53Å
JD 2458145.22 -18.44Å
Combining the X-rays MAXI data (Matsuoka, M. et al., 2009, PASJ, 61, 999),
H-alpha data by Reig et al.(2016, A&A 590, A122) and our data, we find that:
(1) there is a clear similarity between the variability of EW(Ha) and 2-10 keV X-ray flux;
(2) the recent decrease of X-ray flux is accompanied with decrease of
EW(Ha) from above 30 Å (March 2017) to 18 Å (February 2018).
On Fig.1 are plotted the EW(Ha) and 2-10 keV X-ray flux (1 day light curve, each 10 observations averaged).
Most probably during the last orbital period the X-ray pulsar severely truncated the outer parts of the circumstellar
Further multiwavelength observations of this source are needed to
explore the geometry and the emission processes in this system.
Fig. 1 H-alpha and X-ray variability of X Per