Supernova impostors are stellar explosions that appear at first to be a supernova but do not destroy their progenitor stars. As such, they are a class of extra-powerful novae. They are also known as Type V supernovae, Eta Carinae analogs, and giant eruptions of luminous blue variables (LBV).[2]
Supernova impostors appear as remarkably faint supernovae of spectral type IIn—which have hydrogen in their spectrum and narrow spectral lines that indicate relatively low gas speeds. These impostors exceed their pre-outburst states by several magnitudes, with typical peak absolute visual magnitudes of −11 to −14, making these outbursts as bright as the most luminous stars. The trigger mechanism of these outbursts remains unexplained, though it is thought to be caused by violating the classical Eddington luminosity limit, initiating severe mass loss. If the ratio of radiated energy to kinetic energy is near unity, as in Eta Carinae, then we might expect an ejected mass of about 0.16 solar masses.
One supernova impostor that made news after the fact was the one observed on October 20, 2004, in the galaxy UGC 4904 by Japanese amateur astronomer Kōichi Itagaki. This LBV star exploded just two years later, on October 11, 2006, as supernova SN 2006jc.[4]
^ abSmith, Nathan; Weidong, Li; Silverman, Jeffrey; Ganeshalingam, Mo; Filippenko, Alexei (2011). "Luminous Blue Variable eruptions and related transients: Diversity of progenitors and outburst properties". Monthly Notices of the Royal Astronomical Society. 415 (1): 773–810. arXiv:1010.3718. Bibcode:2011MNRAS.415..773S. doi:10.1111/j.1365-2966.2011.18763.x. S2CID 85440811.
^Smith, Nathan; Ganeshalingam, Mohan; Chornock, Ryan; Filippenko, Alexei; Weidong, Li; et al. (2009). "SN 2008S: A Cool Super-Eddington Wind in a Supernova Impostor". Astrophysical Journal Letters. 697 (1): L49–L53. arXiv:0811.3929. Bibcode:2009ApJ...697L..49S. doi:10.1088/0004-637X/697/1/L49. S2CID 17627678.
^Kochanek, C.S.; Szczygiel, D.M.; Stanek, K.Z. (2010). "The Supernova Impostor Impostor SN 1961V: Spitzer Shows That Zwicky Was Right (Again)". The Astrophysical Journal. 737 (2): 76. arXiv:1010.3704. Bibcode:2011ApJ...737...76K. doi:10.1088/0004-637X/737/2/76. S2CID 118483939.
supernova, impostor, stellar, explosions, that, appear, first, supernova, destroy, their, progenitor, stars, such, they, class, extra, powerful, novae, they, also, known, type, supernovae, carinae, analogs, giant, eruptions, luminous, blue, variables, 3184, sh. Supernova impostors are stellar explosions that appear at first to be a supernova but do not destroy their progenitor stars As such they are a class of extra powerful novae They are also known as Type V supernovae Eta Carinae analogs and giant eruptions of luminous blue variables LBV 2 NGC 3184 showing SN impostor SN 2010dn 1 Contents 1 Appearance origin and mass loss 2 Examples 3 See also 4 ReferencesAppearance origin and mass loss editSupernova impostors appear as remarkably faint supernovae of spectral type IIn which have hydrogen in their spectrum and narrow spectral lines that indicate relatively low gas speeds These impostors exceed their pre outburst states by several magnitudes with typical peak absolute visual magnitudes of 11 to 14 making these outbursts as bright as the most luminous stars The trigger mechanism of these outbursts remains unexplained though it is thought to be caused by violating the classical Eddington luminosity limit initiating severe mass loss If the ratio of radiated energy to kinetic energy is near unity as in Eta Carinae then we might expect an ejected mass of about 0 16 solar masses Examples editPossible examples of supernova impostors include the Great Eruption of Eta Carinae P Cygni SN 1961V 3 SN 1954J SN 1997bs SN 2008S in NGC 6946 and SN 2010dn 1 where detections of the surviving progenitor stars are claimed One supernova impostor that made news after the fact was the one observed on October 20 2004 in the galaxy UGC 4904 by Japanese amateur astronomer Kōichi Itagaki This LBV star exploded just two years later on October 11 2006 as supernova SN 2006jc 4 See also editFailed supernovaReferences edit a b Smith Nathan Weidong Li Silverman Jeffrey Ganeshalingam Mo Filippenko Alexei 2011 Luminous Blue Variable eruptions and related transients Diversity of progenitors and outburst properties Monthly Notices of the Royal Astronomical Society 415 1 773 810 arXiv 1010 3718 Bibcode 2011MNRAS 415 773S doi 10 1111 j 1365 2966 2011 18763 x S2CID 85440811 Smith Nathan Ganeshalingam Mohan Chornock Ryan Filippenko Alexei Weidong Li et al 2009 SN 2008S A Cool Super Eddington Wind in a Supernova Impostor Astrophysical Journal Letters 697 1 L49 L53 arXiv 0811 3929 Bibcode 2009ApJ 697L 49S doi 10 1088 0004 637X 697 1 L49 S2CID 17627678 Kochanek C S Szczygiel D M Stanek K Z 2010 The Supernova Impostor Impostor SN 1961V Spitzer Shows That Zwicky Was Right Again The Astrophysical Journal 737 2 76 arXiv 1010 3704 Bibcode 2011ApJ 737 76K doi 10 1088 0004 637X 737 2 76 S2CID 118483939 NASA Supernova Imposter Goes Supernova Nasa gov Retrieved 2010 01 13 Retrieved from https en wikipedia org w index php title Supernova impostor amp oldid 1170003730, wikipedia, wiki, book, books, library,
