A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Analysis of optical spectroscopy and photometry of the type I X-ray bursting system UW CrB
Tekijät: Kennedy, Mark R.; Callanan, P.; Garnavich, P. M.; Breton, R. P.; Brown, A. J.; Segura, N. Castro; Dhillon, V. S.; Dyer, M. J.; Fijma, S.; Garbutt, J.; Green, M. J.; Hakala, P.; Jiminez-Ibarra, F.; Kerry, P.; Littlefair, S.; Munday, J.; Mason, P. A.; Mata-Sanchez, D.; Munoz-Darias, T.; Parsons, S.; Pelisoli, I.; Sahman, D.
Kustantaja: Maynooth University
Julkaisuvuosi: 2025
Journal: Open journal of astrophysics
Tietokannassa oleva lehden nimi: The Open Journal of Astrophysics
Vuosikerta: 8
eISSN: 2565-6120
DOI: https://doi.org/10.33232/001c.140729
Verkko-osoite: https://doi.org/10.33232/001c.140729
Rinnakkaistallenteen osoite: https://arxiv.org/abs/2408.06404v2
Preprintin osoite: https://arxiv.org/abs/2408.06404v1
UW Coronae Borealis (UW CrB) is a low mass X-ray binary that shows both Type 1 X-ray and optical bursts, which typically last for 20 s. The system has a binary period of close to 2 hours and is thought to have a relatively high inclination due to the presence of an eclipse in the optical light curve. There is also evidence that an asymmetric disc is present in the system, which precesses every 5.5 days based on changes in the depth of the eclipse. In this paper, we present optical photometry and spectroscopy of UW CrB taken over 2 years. We update the orbital ephemeris using observed optical eclipses and refine the orbital period to 110.97680(1) min. A total of 17 new optical bursts are presented, with 10 of these bursts being resolved temporally. The average e-folding time of 19 ± 3s for the bursts is consistent with the previously found value. Optical bursts are observed during a previously identified gap in orbital phase centred on ϕ = 0.967, meaning the reprocessing site is not eclipsed as previously thought. Finally, we find that the apparent P-Cygni profiles present in some of the atomic lines in the optical spectra are due to transient absorption.
Julkaisussa olevat rahoitustiedot:
M.R.K. and R.P.B. acknowledge support from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 715051; Spiders). M.R.K acknowledges support from the Royal Society in the form of a Newton International Fellowship (NIF No. NF171019), and the Irish Research Council in the form of a Government of Ireland Postdoctoral Fellowship (GOIPD/2021/670: Invisible Monsters). P.A.M acknowledges support from Picture Rocks Observatory. I.P. acknowledges support from a Royal Society University Research Fellowship (URF\R1\231496). D.M.S and T.M-D. acknowledge support from the Spanish Agencia estatal de investigaci´on via PID2021-124879NB-I00. D.M.S. also acknowledges support via a Ramon y Cajal Fellowship RYC2023-044941.
