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Title: AN ECHO OF SUPERNOVA 2008bk

Abstract

I have discovered a prominent light echo around the low-luminosity Type II-plateau supernova (SN) 2008bk in NGC 7793, seen in archival images obtained with the Wide Field Channel of the Advanced Camera for Surveys on board the Hubble Space Telescope (HST). The echo is a partial ring, brighter to the north and east than to the south and west. The analysis of the echo I present suggests that it is due to the SN light pulse scattered by a sheet, or sheets, of dust located Almost-Equal-To 15 pc from the SN. The composition of the dust is assumed to be of standard Galactic diffuse interstellar grains. The visual extinction of the dust responsible for the echo is A{sub V} Almost-Equal-To 0.05 mag in addition to the extinction due to the Galactic foreground toward the host galaxy. That the SN experienced much less overall extinction implies that it is seen through a less dense portion of the interstellar medium in its environment. The late-time HST photometry of SN 2008bk also clearly demonstrates that the progenitor star has vanished.

Authors:
 [1]
  1. Spitzer Science Center/Caltech, Mailcode 220-6, Pasadena, CA 91125 (United States)
Publication Date:
OSTI Identifier:
22118681
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 146; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; CAMERAS; COSMIC DUST; GALAXIES; GALAXY CLUSTERS; IMAGES; INTERSTELLAR GRAINS; LUMINOSITY; PHOTOMETRY; PULSES; SPACE; SUPERNOVAE; TELESCOPES; VISIBLE RADIATION

Citation Formats

Van Dyk, Schuyler D., E-mail: vandyk@ipac.caltech.edu. AN ECHO OF SUPERNOVA 2008bk. United States: N. p., 2013. Web. doi:10.1088/0004-6256/146/2/24.
Van Dyk, Schuyler D., E-mail: vandyk@ipac.caltech.edu. AN ECHO OF SUPERNOVA 2008bk. United States. doi:10.1088/0004-6256/146/2/24.
Van Dyk, Schuyler D., E-mail: vandyk@ipac.caltech.edu. 2013. "AN ECHO OF SUPERNOVA 2008bk". United States. doi:10.1088/0004-6256/146/2/24.
@article{osti_22118681,
title = {AN ECHO OF SUPERNOVA 2008bk},
author = {Van Dyk, Schuyler D., E-mail: vandyk@ipac.caltech.edu},
abstractNote = {I have discovered a prominent light echo around the low-luminosity Type II-plateau supernova (SN) 2008bk in NGC 7793, seen in archival images obtained with the Wide Field Channel of the Advanced Camera for Surveys on board the Hubble Space Telescope (HST). The echo is a partial ring, brighter to the north and east than to the south and west. The analysis of the echo I present suggests that it is due to the SN light pulse scattered by a sheet, or sheets, of dust located Almost-Equal-To 15 pc from the SN. The composition of the dust is assumed to be of standard Galactic diffuse interstellar grains. The visual extinction of the dust responsible for the echo is A{sub V} Almost-Equal-To 0.05 mag in addition to the extinction due to the Galactic foreground toward the host galaxy. That the SN experienced much less overall extinction implies that it is seen through a less dense portion of the interstellar medium in its environment. The late-time HST photometry of SN 2008bk also clearly demonstrates that the progenitor star has vanished.},
doi = {10.1088/0004-6256/146/2/24},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 2,
volume = 146,
place = {United States},
year = 2013,
month = 8
}
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