wavelength monitoring
Recently Published Documents


TOTAL DOCUMENTS

72
(FIVE YEARS 5)

H-INDEX

10
(FIVE YEARS 1)

2021 ◽  
Author(s):  
Egor Liokumovitch ◽  
Ziv Glasser ◽  
Leeju Singh ◽  
Shmuel Sternklar ◽  
Rita Abramov

2019 ◽  
Vol 621 ◽  
pp. A94 ◽  
Author(s):  
L. Ducci ◽  
C. Malacaria ◽  
P. Romano ◽  
L. Ji ◽  
E. Bozzo ◽  
...  

AXJ0049.4–7323 (SXP 756) is a Be/X-ray binary that shows an unusual and poorly understood optical variability that consists of periodic and bright optical outbursts, simultaneous with X-ray outbursts, characterised by a highly asymmetric profile. The periodicity of the outbursts is thought to correspond to the orbital period of the neutron star. To understand the peculiar behaviour shown by this source, we performed the first multi-wavelength monitoring campaign during the periastron passage of December 2017. The monitoring lasted for about 37 days and consisted of X-ray, near-ultraviolet, and optical data from the Neil Gehrels Swift Observatory, the optical I band from the OGLE survey, and spectroscopic observations of the Hα line performed with the 3.9 m Anglo-Australian Telescope. These observations revealed AXJ0049.4–7323 during an anomalous outburst having remarkably different properties compared to the previous ones. In the I band, it showed a longer rise timescale (∼60 days instead of 1–5 days) and a longer decay timescale. At the peak of the outburst, it showed a sudden increase in luminosity in the I band, corresponding to the onset of the X-ray outburst. The monitoring of the Hα emission line showed a fast and highly variable profile composed of three peaks with variable reciprocal brightness. To our knowledge, this is the second observation of a variable three-peak Hα profile of a Be/X-ray binary, after A0535+26. We interpreted these results as a circumstellar disc warped by tidal interactions with the neutron star in a high eccentricity orbit during its periastron passage. The fast jump in optical luminosity at the peak of the outburst and the previous asymmetric outbursts might be caused by the reprocessing of the X-ray photons in the circumstellar disc or the tidal displacement of a large amount of material from the circumstellar disc or the outer layers of the donor star during the periastron passage of the neutron star, which led to an increase in size of the region emitting in the I band. Further multi-wavelength observations are necessary to discriminate among the different scenarios proposed to explain the puzzling optical and X-ray properties of AXJ0049.4–7323.


2017 ◽  
Vol 30 (0) ◽  
pp. 117-120 ◽  
Author(s):  
V. L. Oknyansky ◽  
C. M. Gaskell ◽  
N. A. Huseynov ◽  
Kh. M. Mikailov ◽  
V. M. Lipunov ◽  
...  

Galaxies ◽  
2016 ◽  
Vol 4 (4) ◽  
pp. 47 ◽  
Author(s):  
Svetlana Jorstad ◽  
Alan Marscher

2016 ◽  
Vol 53 (2) ◽  
pp. 022601
Author(s):  
Jin Ke ◽  
Liu ◽  
Yongqiang ◽  
Yang Chongmin ◽  
Wang Yinghui ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document