skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: SN 2002bu-ANOTHER SN 2008S-LIKE TRANSIENT

Abstract

We observed supernova (SN) 2002bu in the near-IR with the Hubble Space Telescope (HST), the mid-IR with the Spitzer Space Telescope, and in X-rays with Swift 10 years after the explosion. If the faint L {sub H} {approx} 10{sup 2} L {sub Sun} HST near-IR source at the transient position is the near-IR counterpart of SN 2002bu, then the source has dramatically faded between 2004 and 2012, from L {approx_equal} 10{sup 6.0} L {sub Sun} to L {approx_equal} 10{sup 4.5} L {sub Sun }. It is still heavily obscured, {tau} {sub V} {approx_equal} 5 in graphitic dust models, with almost all the energy radiated in the mid-IR. The radius of the dust emission is increasing as R{proportional_to}t {sup 0.7{+-}0.4} and the optical depth is dropping as {tau} {sub V}{proportional_to}t {sup -1.3{+-}0.4}. The evolution expected for an expanding shell of material, {tau} {sub V}{proportional_to}t {sup -2}, is ruled out at approximately 2{sigma}, while the {tau} {sub V}{proportional_to}t {sup -0.8} to t {sup -1} optical depth scaling for a shock passing through a pre-existing wind is consistent with the data. If the near-IR source is a chance superposition, the present-day source can be moderately more luminous, significantly more obscured and evolving moremore » slowly. While we failed to detect X-ray emission, the X-ray flux limits are consistent with the present-day emissions being powered by an expanding shock wave. SN 2002bu is clearly a member of the SN 2008S class of transients, but continued monitoring of the evolution of the spectral energy distribution is needed to conclusively determine the nature of the transient.« less

Authors:
;  [1];  [2]
  1. Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210 (United States)
  2. Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks Street, Norman, OK 73019 (United States)
Publication Date:
OSTI Identifier:
22086349
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 760; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; COSMIC DUST; ENERGY SPECTRA; GRAPHITE; INFRARED SPECTRA; NEAR INFRARED RADIATION; PHOTON EMISSION; SHOCK WAVES; STAR EVOLUTION; STELLAR WINDS; SUPERNOVAE; TELESCOPES; TRANSIENTS; X RADIATION

Citation Formats

Szczygiel, D M, Kochanek, C S, and Dai, X. SN 2002bu-ANOTHER SN 2008S-LIKE TRANSIENT. United States: N. p., 2012. Web. doi:10.1088/0004-637X/760/1/20.
Szczygiel, D M, Kochanek, C S, & Dai, X. SN 2002bu-ANOTHER SN 2008S-LIKE TRANSIENT. United States. https://doi.org/10.1088/0004-637X/760/1/20
Szczygiel, D M, Kochanek, C S, and Dai, X. 2012. "SN 2002bu-ANOTHER SN 2008S-LIKE TRANSIENT". United States. https://doi.org/10.1088/0004-637X/760/1/20.
@article{osti_22086349,
title = {SN 2002bu-ANOTHER SN 2008S-LIKE TRANSIENT},
author = {Szczygiel, D M and Kochanek, C S and Dai, X},
abstractNote = {We observed supernova (SN) 2002bu in the near-IR with the Hubble Space Telescope (HST), the mid-IR with the Spitzer Space Telescope, and in X-rays with Swift 10 years after the explosion. If the faint L {sub H} {approx} 10{sup 2} L {sub Sun} HST near-IR source at the transient position is the near-IR counterpart of SN 2002bu, then the source has dramatically faded between 2004 and 2012, from L {approx_equal} 10{sup 6.0} L {sub Sun} to L {approx_equal} 10{sup 4.5} L {sub Sun }. It is still heavily obscured, {tau} {sub V} {approx_equal} 5 in graphitic dust models, with almost all the energy radiated in the mid-IR. The radius of the dust emission is increasing as R{proportional_to}t {sup 0.7{+-}0.4} and the optical depth is dropping as {tau} {sub V}{proportional_to}t {sup -1.3{+-}0.4}. The evolution expected for an expanding shell of material, {tau} {sub V}{proportional_to}t {sup -2}, is ruled out at approximately 2{sigma}, while the {tau} {sub V}{proportional_to}t {sup -0.8} to t {sup -1} optical depth scaling for a shock passing through a pre-existing wind is consistent with the data. If the near-IR source is a chance superposition, the present-day source can be moderately more luminous, significantly more obscured and evolving more slowly. While we failed to detect X-ray emission, the X-ray flux limits are consistent with the present-day emissions being powered by an expanding shock wave. SN 2002bu is clearly a member of the SN 2008S class of transients, but continued monitoring of the evolution of the spectral energy distribution is needed to conclusively determine the nature of the transient.},
doi = {10.1088/0004-637X/760/1/20},
url = {https://www.osti.gov/biblio/22086349}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 760,
place = {United States},
year = {Tue Nov 20 00:00:00 EST 2012},
month = {Tue Nov 20 00:00:00 EST 2012}
}