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Title: AN EXTENDED GRID OF NOVA MODELS. III. VERY LUMINOUS, RED NOVAE

Abstract

Extremely luminous, red eruptive variables like RV in M31 are being suggested as exemplars of a new class of astrophysical objects. Our greatly extended series of nova simulations shows that classical nova models can produce very red, luminous eruptions. In a poorly studied corner of three-dimensional nova parameter space (very cold, low-mass white dwarfs, accreting at very low rates) we find bona fide classical novae that are very luminous and red because they eject very slowly moving, massive envelopes. A crucial prediction of these nova models-in contrast to the predictions of merging star ('mergeburst') models-is that a hot remnant, the underlying white dwarf, will emerge after the massive ejected envelope has expanded enough to become optically thin. This blue remnant must fade on a timescale of decades-much faster than a 'mergeburst', which must fade on timescales of millennia or longer. Furthermore, the cooling nova white dwarf and its expanding ejecta must become redder in the years after eruption, while a contracting mergeburst must become hotter and bluer. We predict that red novae will always brighten to L {approx} 1000 L{sub sun} for about one year before rising to the maximum luminosity at L {approx} 10{sup 6}-10{sup 7} L{sub sun}. Themore » maximum luminosity attainable by a nova is likely to be L {approx} 10{sup 7} L{sub sun}, corresponding to M {approx} -12. In an accompanying paper, we describe a fading, luminous blue candidate for the remnant of M31-RV; it is observed with the Hubble Space Telescope to be compatible only with the nova model.« less

Authors:
;  [1]; ; ;  [2]
  1. Department of Astrophysics, American Museum of Natural History, Central Park West and 79th Street, New York, NY 10024-5192 (United States)
  2. Department of Geophysics and Planetary Sciences, Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978 (Israel)
Publication Date:
OSTI Identifier:
21474385
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 725; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/725/1/831
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCRETION DISKS; ASTROPHYSICS; COMPUTERIZED SIMULATION; COSMOLOGICAL MODELS; ERUPTION; FORECASTING; LUMINOSITY; NOVAE; TELESCOPES; THREE-DIMENSIONAL CALCULATIONS; WHITE DWARF STARS; BINARY STARS; DWARF STARS; ERUPTIVE VARIABLE STARS; MATHEMATICAL MODELS; OPTICAL PROPERTIES; PHYSICAL PROPERTIES; PHYSICS; SIMULATION; STARS; VARIABLE STARS

Citation Formats

Shara, Michael M., Zurek, David, Yaron, Ofer, Prialnik, Dina, and Kovetz, Attay. AN EXTENDED GRID OF NOVA MODELS. III. VERY LUMINOUS, RED NOVAE. United States: N. p., 2010. Web. doi:10.1088/0004-637X/725/1/831.
Shara, Michael M., Zurek, David, Yaron, Ofer, Prialnik, Dina, & Kovetz, Attay. AN EXTENDED GRID OF NOVA MODELS. III. VERY LUMINOUS, RED NOVAE. United States. doi:10.1088/0004-637X/725/1/831.
Shara, Michael M., Zurek, David, Yaron, Ofer, Prialnik, Dina, and Kovetz, Attay. Fri . "AN EXTENDED GRID OF NOVA MODELS. III. VERY LUMINOUS, RED NOVAE". United States. doi:10.1088/0004-637X/725/1/831.
@article{osti_21474385,
title = {AN EXTENDED GRID OF NOVA MODELS. III. VERY LUMINOUS, RED NOVAE},
author = {Shara, Michael M. and Zurek, David and Yaron, Ofer and Prialnik, Dina and Kovetz, Attay},
abstractNote = {Extremely luminous, red eruptive variables like RV in M31 are being suggested as exemplars of a new class of astrophysical objects. Our greatly extended series of nova simulations shows that classical nova models can produce very red, luminous eruptions. In a poorly studied corner of three-dimensional nova parameter space (very cold, low-mass white dwarfs, accreting at very low rates) we find bona fide classical novae that are very luminous and red because they eject very slowly moving, massive envelopes. A crucial prediction of these nova models-in contrast to the predictions of merging star ('mergeburst') models-is that a hot remnant, the underlying white dwarf, will emerge after the massive ejected envelope has expanded enough to become optically thin. This blue remnant must fade on a timescale of decades-much faster than a 'mergeburst', which must fade on timescales of millennia or longer. Furthermore, the cooling nova white dwarf and its expanding ejecta must become redder in the years after eruption, while a contracting mergeburst must become hotter and bluer. We predict that red novae will always brighten to L {approx} 1000 L{sub sun} for about one year before rising to the maximum luminosity at L {approx} 10{sup 6}-10{sup 7} L{sub sun}. The maximum luminosity attainable by a nova is likely to be L {approx} 10{sup 7} L{sub sun}, corresponding to M {approx} -12. In an accompanying paper, we describe a fading, luminous blue candidate for the remnant of M31-RV; it is observed with the Hubble Space Telescope to be compatible only with the nova model.},
doi = {10.1088/0004-637X/725/1/831},
journal = {Astrophysical Journal},
number = 1,
volume = 725,
place = {United States},
year = {Fri Dec 10 00:00:00 EST 2010},
month = {Fri Dec 10 00:00:00 EST 2010}
}
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