OGLE-BLG504.12.201843: a possible extreme dwarf nova
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F22%3A10456324" target="_blank" >RIV/00216208:11320/22:10456324 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=A9hb.3xycr" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=A9hb.3xycr</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1093/mnras/stac2864" target="_blank" >10.1093/mnras/stac2864</a>
Alternative languages
Result language
angličtina
Original language name
OGLE-BLG504.12.201843: a possible extreme dwarf nova
Original language description
We present the analysis of existing optical photometry and new optical spectroscopy of the candidate cataclysmic variable star OGLE-BLG504.12.201843. As was shown previously, this object has an orbital period of 0.523419 d and exhibits year-long outbursts with a mean period of 973 d. Using digitized photographic archives, we show that the earliest recorded outburst occurred in 1910. We propose that this object is a U Gem-type dwarf nova (DN) with extreme properties. The orbital variability of the system in outburst shows clear signs of an accretion disc, from which the outburst likely originates. During quiescence, the object slowly brightens by up to 0.75 mag in the I band over 600 d before the outburst and exhibits small flares with amplitude less than or similar to 2 mag in the I band. We interpret the gradual brightening as an increase in the luminosity and temperature of the accretion disc, which is theoretically predicted but only rarely seen in DNe. The origin of small flares remains unexplained. The spectra show Balmer absorption lines both in quiescence and outburst, which can be associated with a bright secondary star or a cold accretion disc. During outbursts, emission lines with full width at half-maximum of about 450 km s(-1) appear; however, they lack typical double-peaked profiles. We suggest that either these lines originate in the disc winds or the orbital inclination is low, the latter being consistent with constrains obtained from the orbital variability of the system. Due to its extreme properties and peculiarities, OGLE-BLG504.12.201843 is an excellent object for further follow-up studies.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10308 - Astronomy (including astrophysics,space science)
Result continuities
Project
<a href="/en/project/LTAUSA18093" target="_blank" >LTAUSA18093: Time-variability in astronomy: participation in project All-Sky Automated Survey for Supernovae</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Monthly Notices of the Royal Astronomical Society
ISSN
0035-8711
e-ISSN
1365-2966
Volume of the periodical
517
Issue of the periodical within the volume
2
Country of publishing house
GB - UNITED KINGDOM
Number of pages
11
Pages from-to
2746-2756
UT code for WoS article
000869893300037
EID of the result in the Scopus database
2-s2.0-85145348178