A Multiwavelength View of SPLUS J102139.31-282247.5: an X-ray Luminous and Eclipsing Dwarf Nova

@misc{araujo2026multiwavelength,
  title = {{A Multiwavelength View of SPLUS J102139.31-282247.5: an X-ray Luminous and Eclipsing Dwarf Nova}},
  author = {Amanda Silva de Araujo and Raimundo Lopes de Oliveira and Koji Mukai and Raymundo Baptista and Albert Bruch and Romualdo Eleuterio and Angela Krabbe and Claudia Mendes de Oliveira},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.22790},
  eprint = {2610.22790},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.22790},
}

TY  - UNPB
TI  - A Multiwavelength View of SPLUS J102139.31-282247.5: an X-ray Luminous and Eclipsing Dwarf Nova
AU  - Amanda Silva de Araujo
AU  - Raimundo Lopes de Oliveira
AU  - Koji Mukai
AU  - Raymundo Baptista
AU  - Albert Bruch
AU  - Romualdo Eleuterio
AU  - Angela Krabbe
AU  - Claudia Mendes de Oliveira
PY  - 2026
DA  - 2026/10/16
PB  - arXiv
DO  - 10.48550/arxiv.2610.22790
UR  - https://arxiv.org/abs/2610.22790
AB  - We report the independent discovery of the cataclysmic variable (CV) SPLUS J102139.31-282247.5 using Southern Photometric Local Universe Survey 12 band photometry, following its initial identification via ASAS-SN variability. Here, we investigate the system using optical photometry alongside optical and X-ray spectroscopy. High-cadence optical light curves from publicly available TESS data and a dedicated campaign at the Pico dos Dias Observatory in Brazil revealed a highly inclined system exhibiting pronounced eclipses with an orbital period of 1.81 hours. We found no evidence of a WD spin period. Despite seasonal gaps, the long-term ASAS-SN light curve revealed several outbursts (15 with Δmag ∼ 1.5 brighter than the mean magnitude) and one superoutburst over the past decade. During Swift X-ray telescope observations, the system exhibited X-ray luminosity of 8.5 × 10^31 erg s^−1 in the 0.3-10\,keV band, originating from thermal plasma emission at a temperature consistent with accretion shocks. Optical spectroscopy from the Gemini Multi-Object Spectrographs on the Gemini South telescope confirms the CV nature of the system, showing strong, double-peaked H and HeI emission lines alongside a weak HeII4686 line. Altogether, these features strongly support the classification of SPLUS J102139.31-282247.5 as a quiescent, eclipsing dwarf nova with an unusually high X-ray luminosity.
ER  -