X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S

David Pooley, Walter H.G. Lewin, Derek Brindley Fox, Jon M. Miller, Christina K. Lacey, Schuyler D. Van Dyk, Kurt W. Weiler, Richard A. Sramek, Alexei V. Filippenko, Douglas C. Leonard, Stefan Immler, Roger A. Chevalier, Andrew C. Fabian, Claes Fransson, Ken'ichi Nomoto

Research output: Contribution to journalArticle

80 Citations (Scopus)

Abstract

Observations of the Type II-P (plateau) supernova SN 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SNe ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate nonradiative interaction of SN ejecta with a power-law density profile (ρ r-n, with n ∼ 7) for a pre-SN wind with a low mass-loss rate of ∼2 × 10-6 M yr-1 for a wind velocity of 10 km s-1, in agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4-2.0 keV X-ray flux at ∼100 days after explosion. SN 1998S, at an age of more than 3 yr, is still bright in X-rays and is increasing in flux density at centimeter radio wavelengths. Spectral fits to the Chandra data show that many heavy elements (Ne, Al, Si, S, Ar, and Fe) are overabundant with respect to solar values. We compare the observed elemental abundances and abundance ratios to theoretical calculations and find that our data are consistent with a progenitor mass of approximately 15-20 M if the heavy-element ejecta are radially mixed out to a high velocity. If the X-ray emission is from the reverse shock wave region, the supernova density profile must be moderately flat at a velocity ∼104 km s-1, the shock front is nonradiative at the time of the observations, and the mass-loss rate is (1-2) × 10-4 M yr-1 for a presupernova wind velocity of 10 km s-1. This result is also supported by modeling of the radio emission, which implies that SN 1998S is surrounded by a clumpy or filamentary CSM established by a high mass-loss rate, ∼2 × 10-4 M yr-1, from the presupernova star.

Original languageEnglish (US)
Pages (from-to)932-943
Number of pages12
JournalAstrophysical Journal
Volume572
Issue number2 I
DOIs
StatePublished - Jun 20 2002

Fingerprint

radio observation
supernovae
radio
ejecta
x rays
wind velocity
heavy elements
profiles
wavelength
shock fronts
stellar winds
radio emission
shock wave
wavelengths
explosions
shock waves
explosion
plateaus
power law
flux density

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Pooley, D., Lewin, W. H. G., Fox, D. B., Miller, J. M., Lacey, C. K., Van Dyk, S. D., ... Nomoto, K. (2002). X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S. Astrophysical Journal, 572(2 I), 932-943. https://doi.org/10.1086/340346
Pooley, David ; Lewin, Walter H.G. ; Fox, Derek Brindley ; Miller, Jon M. ; Lacey, Christina K. ; Van Dyk, Schuyler D. ; Weiler, Kurt W. ; Sramek, Richard A. ; Filippenko, Alexei V. ; Leonard, Douglas C. ; Immler, Stefan ; Chevalier, Roger A. ; Fabian, Andrew C. ; Fransson, Claes ; Nomoto, Ken'ichi. / X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S. In: Astrophysical Journal. 2002 ; Vol. 572, No. 2 I. pp. 932-943.
@article{bce2374721e249baa333ec1d6c0ecfbe,
title = "X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S",
abstract = "Observations of the Type II-P (plateau) supernova SN 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SNe ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate nonradiative interaction of SN ejecta with a power-law density profile (ρ r-n, with n ∼ 7) for a pre-SN wind with a low mass-loss rate of ∼2 × 10-6 M⊙ yr-1 for a wind velocity of 10 km s-1, in agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4-2.0 keV X-ray flux at ∼100 days after explosion. SN 1998S, at an age of more than 3 yr, is still bright in X-rays and is increasing in flux density at centimeter radio wavelengths. Spectral fits to the Chandra data show that many heavy elements (Ne, Al, Si, S, Ar, and Fe) are overabundant with respect to solar values. We compare the observed elemental abundances and abundance ratios to theoretical calculations and find that our data are consistent with a progenitor mass of approximately 15-20 M⊙ if the heavy-element ejecta are radially mixed out to a high velocity. If the X-ray emission is from the reverse shock wave region, the supernova density profile must be moderately flat at a velocity ∼104 km s-1, the shock front is nonradiative at the time of the observations, and the mass-loss rate is (1-2) × 10-4 M⊙ yr-1 for a presupernova wind velocity of 10 km s-1. This result is also supported by modeling of the radio emission, which implies that SN 1998S is surrounded by a clumpy or filamentary CSM established by a high mass-loss rate, ∼2 × 10-4 M⊙ yr-1, from the presupernova star.",
author = "David Pooley and Lewin, {Walter H.G.} and Fox, {Derek Brindley} and Miller, {Jon M.} and Lacey, {Christina K.} and {Van Dyk}, {Schuyler D.} and Weiler, {Kurt W.} and Sramek, {Richard A.} and Filippenko, {Alexei V.} and Leonard, {Douglas C.} and Stefan Immler and Chevalier, {Roger A.} and Fabian, {Andrew C.} and Claes Fransson and Ken'ichi Nomoto",
year = "2002",
month = "6",
day = "20",
doi = "10.1086/340346",
language = "English (US)",
volume = "572",
pages = "932--943",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2 I",

}

Pooley, D, Lewin, WHG, Fox, DB, Miller, JM, Lacey, CK, Van Dyk, SD, Weiler, KW, Sramek, RA, Filippenko, AV, Leonard, DC, Immler, S, Chevalier, RA, Fabian, AC, Fransson, C & Nomoto, K 2002, 'X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S', Astrophysical Journal, vol. 572, no. 2 I, pp. 932-943. https://doi.org/10.1086/340346

X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S. / Pooley, David; Lewin, Walter H.G.; Fox, Derek Brindley; Miller, Jon M.; Lacey, Christina K.; Van Dyk, Schuyler D.; Weiler, Kurt W.; Sramek, Richard A.; Filippenko, Alexei V.; Leonard, Douglas C.; Immler, Stefan; Chevalier, Roger A.; Fabian, Andrew C.; Fransson, Claes; Nomoto, Ken'ichi.

In: Astrophysical Journal, Vol. 572, No. 2 I, 20.06.2002, p. 932-943.

Research output: Contribution to journalArticle

TY - JOUR

T1 - X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S

AU - Pooley, David

AU - Lewin, Walter H.G.

AU - Fox, Derek Brindley

AU - Miller, Jon M.

AU - Lacey, Christina K.

AU - Van Dyk, Schuyler D.

AU - Weiler, Kurt W.

AU - Sramek, Richard A.

AU - Filippenko, Alexei V.

AU - Leonard, Douglas C.

AU - Immler, Stefan

AU - Chevalier, Roger A.

AU - Fabian, Andrew C.

AU - Fransson, Claes

AU - Nomoto, Ken'ichi

PY - 2002/6/20

Y1 - 2002/6/20

N2 - Observations of the Type II-P (plateau) supernova SN 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SNe ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate nonradiative interaction of SN ejecta with a power-law density profile (ρ r-n, with n ∼ 7) for a pre-SN wind with a low mass-loss rate of ∼2 × 10-6 M⊙ yr-1 for a wind velocity of 10 km s-1, in agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4-2.0 keV X-ray flux at ∼100 days after explosion. SN 1998S, at an age of more than 3 yr, is still bright in X-rays and is increasing in flux density at centimeter radio wavelengths. Spectral fits to the Chandra data show that many heavy elements (Ne, Al, Si, S, Ar, and Fe) are overabundant with respect to solar values. We compare the observed elemental abundances and abundance ratios to theoretical calculations and find that our data are consistent with a progenitor mass of approximately 15-20 M⊙ if the heavy-element ejecta are radially mixed out to a high velocity. If the X-ray emission is from the reverse shock wave region, the supernova density profile must be moderately flat at a velocity ∼104 km s-1, the shock front is nonradiative at the time of the observations, and the mass-loss rate is (1-2) × 10-4 M⊙ yr-1 for a presupernova wind velocity of 10 km s-1. This result is also supported by modeling of the radio emission, which implies that SN 1998S is surrounded by a clumpy or filamentary CSM established by a high mass-loss rate, ∼2 × 10-4 M⊙ yr-1, from the presupernova star.

AB - Observations of the Type II-P (plateau) supernova SN 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SNe ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate nonradiative interaction of SN ejecta with a power-law density profile (ρ r-n, with n ∼ 7) for a pre-SN wind with a low mass-loss rate of ∼2 × 10-6 M⊙ yr-1 for a wind velocity of 10 km s-1, in agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4-2.0 keV X-ray flux at ∼100 days after explosion. SN 1998S, at an age of more than 3 yr, is still bright in X-rays and is increasing in flux density at centimeter radio wavelengths. Spectral fits to the Chandra data show that many heavy elements (Ne, Al, Si, S, Ar, and Fe) are overabundant with respect to solar values. We compare the observed elemental abundances and abundance ratios to theoretical calculations and find that our data are consistent with a progenitor mass of approximately 15-20 M⊙ if the heavy-element ejecta are radially mixed out to a high velocity. If the X-ray emission is from the reverse shock wave region, the supernova density profile must be moderately flat at a velocity ∼104 km s-1, the shock front is nonradiative at the time of the observations, and the mass-loss rate is (1-2) × 10-4 M⊙ yr-1 for a presupernova wind velocity of 10 km s-1. This result is also supported by modeling of the radio emission, which implies that SN 1998S is surrounded by a clumpy or filamentary CSM established by a high mass-loss rate, ∼2 × 10-4 M⊙ yr-1, from the presupernova star.

UR - http://www.scopus.com/inward/record.url?scp=0042829795&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0042829795&partnerID=8YFLogxK

U2 - 10.1086/340346

DO - 10.1086/340346

M3 - Article

AN - SCOPUS:0042829795

VL - 572

SP - 932

EP - 943

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2 I

ER -

Pooley D, Lewin WHG, Fox DB, Miller JM, Lacey CK, Van Dyk SD et al. X-ray, optical, and radio observations of the type II supernovae 1999em and 1998S. Astrophysical Journal. 2002 Jun 20;572(2 I):932-943. https://doi.org/10.1086/340346