V1369 Cen High-resolution Panchromatic Late Nebular Spectra in the Context of a Unified Picture for Nova Ejecta

• Published in: The Astrophysical Journal
• Main Authors: Mason, E, Shore, SN, Aquino, IDG, Izzo, L, Page, K, Schwarz, GJ
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Astronomical Society, IOP Publishing 2019
• Subjects: Science & Technology; Physical Sciences; Astronomy & Astrophysics; stars: novae; cataclysmic variables; stars: individual (V339 Del; V1369 Cen; V959 Mon); line: formation; line: identification; line: profiles; methods: observational; techniques: spectroscopic; GROUND-BASED SPECTROSCOPY; CLASSICAL NOVAE; ABSORPTION SYSTEMS; MASS EJECTION; ULTRAVIOLET; EMISSION; CYG; EVOLUTION; SHELLS; RADIO; Norway; Osborne; Hubble; Observatorio; Sumner; Iceland
• Online Access: https://iopscience.iop.org/article/10.3847/1538-4357/aaa247; http://hdl.handle.net/2381/44707; https://doi.org/10.3847/1538-4357/aaa247

Nova Cen 2013 (V1369 Cen) is the fourth bright nova observed panchromatically through high-resolution UV +optical multiepoch spectroscopy. It is also the nova with the richest set of spectra (in terms of both data quality and number of epochs) thanks to its exceptional brightness. Here, we use the late nebular spectra taken between day ∼250 and day ∼837 after outburst to derive the physical, geometrical, and kinematical properties of the nova. We compare the results with those determined for the other panchromatic studies in this series: T Pyx, V339 Del (nova Del 2013), and V959 Mon (nova Mon 2012). From this we conclude that in all these novae the ejecta geometry and phenomenology can be consistently explained by clumpy gas expelled during a single, brief ejection episode and in ballistic expansion, and not by a wind. For V1369 Cen the ejecta mass (∼1 × 10−4 Me) and filling factor (0.1 f 0.2) are consistent with those of classical novae but larger (by at least an order of magnitude) than those of T Pyx and the recurrent novae. V1369 Cen has an anomalously high (relative to solar) N/C ratio that is beyond the range currently predicted for a CO nova, and the Ne emission line strengths are dissimilar to those of typical ONe or CO white dwarfs. Based on observations made with (1) the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555; (2) the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias; (3) the ESO Very Large Telescope at the Paranal Observatory; and (4) the ESO/MPG 2.2 m in the La Silla Observatory. The authors are grateful to Teddy Cheung, Jordi José Jan-Uwe Ness, Julian Osborne, Francois Teyssier, and Brian Warner for having participated in the 2013 Pisa meeting, helping define this research program. E.M. warmly thanks Pierluigi Selvelli for the enlightening spectroscopic confrontations and the friendly "calories support." S.N.S. thanks Thomas Augusteijn, Bob Gherz, Pierre Jean, Paul Kuin, Sumner Starrfield, Fred Walter, and Laura Chomiuk for discussions; John Telting for his help with the NOT observations; and the Astronomical Institute of the Charles University for a visiting professorship. The authors thank the anonymous referee for the helpful critiques. Facilities: HST(STIS) - Hubble Space Telescope satellite, VLT(UVES) - , NOT(FIES) - Nordic Optical Telescope, Swift(XRT) - Swift Gamma-Ray Burst Mission, AAVSO - American Association of Variable Star Observers International Database. Software: IRAF, Super Mongo, IDL. Peer-reviewed Publisher Version