A Time-dependent Spectral Analysis of γ Cassiopeiae
Abstract We investigated the temporal and spectral features of γ Cassiopeiae’s X-ray emission within the context of the white dwarf (WD) accretion hypothesis. We find that the variabilities present in the X-ray data show two different signals, one primarily due to absorption and the other due to flickering like in nonmagnetic cataclysmic variables. We then use this two-component insight to investigate previously unreported simultaneous XMM and NuSTAR data. The results of model fitting find WD properties consistent with optical studies alongside a significant secondary, thermal source. We propose a secondary shock between the Be decretion disk and WD accretion disk as the source. Finally, we analyzed a unique, low-count-rate event of the XMM light curve as potential evidence for the WD encountering Be decretion disk structures.
Authors
- Pragati Pradhan (ORCID: https://orcid.org/0000-0002-1131-3059)
- Sean J. Gunderson (ORCID: https://orcid.org/0000-0003-2602-6703)
- Dustin K. Swarm (ORCID: https://orcid.org/0000-0003-1898-4223)
- Hans Moritz Günther (ORCID: https://orcid.org/0000-0003-4243-2840)
- Richard Ignace (ORCID: https://orcid.org/0000-0002-7204-5502)
- Joy S. Nichols (ORCID: https://orcid.org/0000-0003-3298-7455)
- Norbert S. Schulz (ORCID: https://orcid.org/0000-0002-0842-7792)
- A. M. T. Pollock (ORCID: https://orcid.org/0000-0002-5725-7072)
- David P. Huenemoerder (ORCID: https://orcid.org/0000-0002-3860-6230)
- J. M. Torrejón (ORCID: https://orcid.org/0000-0002-5967-5163)
Institutions
- East Tennessee State University (US)
- University of Iowa (US)
- University of Alicante (ES)
- Center for Astrophysics Harvard & Smithsonian (US)
- Massachusetts Institute of Technology (US)
- Embry–Riddle Aeronautical University (US)
- University of Sheffield (GB)
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2024-12-27
- DOI
- https://doi.org/10.3847/1538-4357/ad944e
- Citations
- 7
- Primary Topic
- Astrophysics and Cosmic Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 4.62
Funders
- Smithsonian Institution
- National Aeronautics and Space Administration
- Smithsonian Astrophysical Observatory