1000 cataclysmic variables identified from DESI spectroscopy

K. Inight; B. T. Gänsicke; A. Aungwerojwit; P. Izquierdo; C. J. Manser; A. D. Myers; A. Swan; J. R. Thorstensen; J. Aguilar; S. Ahlen; D. Bianchi; D. Brooks; T. Claybaugh; A. de la Macorra; Biprateep Dey; P. Doel; A. Font-Ribera; J. E. Forero-Romero; Satya Gontcho A Gontcho; G. Gutierrez; J. Guy; R. Joyce; S. Juneau; S. E. Koposov; A. Kremin; M. Landriau; L. Le Guillou; A. Meisner; R. Miquel; J. Moustakas; J. Najita; I. Pérez-Ràfols; W. J. Percival; F. Prada; G. Rossi; E. Sanchez; D. Schlegel; M. Schubnell; H. Seo; J. Silber; G. Tarlé; B. A. Weaver; R. Zhou; H. Zou

arXiv · 2607.22836

1000 cataclysmic variables identified from DESI spectroscopy

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Abstract

Most cataclysmic variables (CVs) are discovered when they have an outburst generating an inherent selection bias against CVs that rarely, or never, outburst. CVs discovered by virtue of their spectroscopic characteristics are particularly valuable to offset this bias and we have used an established machine-learning technique to assist in searching 98 966 000 spectra obtained by the Dark Energy Spectroscopic Survey (DESI) to find such CVs. DESI observations are much deeper than previous spectroscopic surveys and we have identified 1029 CVs, 221 of which are new including ten of the AM CVn subtype. We have spectroscopically confirmed 441 CV candidates and obtained 84 new or improved orbital periods. We present revised space density estimates based upon this new data. We have also added ten more to the eight known examples of an intriguing class of CVs which exhibit peculiar changes in accretion.

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K. Inight, B. T. Gänsicke, A. Aungwerojwit, P. Izquierdo, C. J. Manser, A. D. Myers, A. Swan, J. R. Thorstensen, J. Aguilar, S. Ahlen, D. Bianchi, D. Brooks, T. Claybaugh, A. de la Macorra, Biprateep Dey, P. Doel, A. Font-Ribera, J. E. Forero-Romero, Satya Gontcho A Gontcho, G. Gutierrez, J. Guy, R. Joyce, S. Juneau, S. E. Koposov, A. Kremin, M. Landriau, L. Le Guillou, A. Meisner, R. Miquel, J. Moustakas, J. Najita, I. Pérez-Ràfols, W. J. Percival, F. Prada, G. Rossi, E. Sanchez, D. Schlegel, M. Schubnell, H. Seo, J. Silber, G. Tarlé, B. A. Weaver, R. Zhou, H. Zou. 2026-07-24. 1000 cataclysmic variables identified from DESI spectroscopy. https://arxiv.org/abs/2607.22836

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