SWS spectroscopy of the starburst galaxy NGC 3256

D. Rigopoulou; D. Lutz; R. Genzel; E. Egarai; D. Kunze; E. Sturm; H. Feuchtgruber; S. Schaeidt; O. H. Bauer; A. Sternberg; H. Netzer; A. F.M. Moorwood; Th De Graauw

SWS spectroscopy of the starburst galaxy NGC 3256

D. Rigopoulou^*, D. Lutz, R. Genzel, E. Egarai, D. Kunze, E. Sturm, H. Feuchtgruber, S. Schaeidt, O. H. Bauer, A. Sternberg, H. Netzer, A. F.M. Moorwood, Th De Graauw

^*Corresponding author for this work

School of Physics and Astronomy

Research output: Contribution to journal › Article › peer-review

38 Scopus citations

Abstract

We present 2.5-40 μm ISO SWS spectra of the starburst galaxy NGC 3256. We have observed many fine-structure lines of various atomic species as well as three rotational transitions of molecular hydrogen. From the [SIII] 18μm/33μm line ratio we infer low electron densities of ≈ 300 cm^-3 in the HII regions. The observed [NeIII]/[NeII] (15μm/12μm), [ArIII]/[ArII] (8.9μm/6.9μm), and [SIV]/[SIII] (10.5μm/18.7μm) line ratios are consistent with an ionizing radiation field with an effective temperature of ≈ 41000 K. Comparison of the observed fine-structure line ratios with theoretical models of nebular emission from evolving starbursts shows that stars with masses ≥ 50 M_⊙ have been forming recently in NGC 3256. The H₂ observations reveal the presence of warm molecular gas. We estimate that ≈ 10⁹ M_⊙ of H₂ gas is present at temperatures close to 150 K. This mass corresponds to a few percent of the total cold molecular mass as estimated from CO studies.

Original language	English
Pages (from-to)	L125-L128
Journal	Astronomy and Astrophysics
Volume	315
Issue number	2
State	Published - 10 Nov 1996

Keywords

Galaxies: individual (NGC 3256)
Galaxies: interactions
Galaxies: starburst
Infrared: galaxies

Cite this

@article{80109faea57245b481dbc652cb5acaae,

title = "SWS spectroscopy of the starburst galaxy NGC 3256",

abstract = "We present 2.5-40 μm ISO SWS spectra of the starburst galaxy NGC 3256. We have observed many fine-structure lines of various atomic species as well as three rotational transitions of molecular hydrogen. From the [SIII] 18μm/33μm line ratio we infer low electron densities of ≈ 300 cm-3 in the HII regions. The observed [NeIII]/[NeII] (15μm/12μm), [ArIII]/[ArII] (8.9μm/6.9μm), and [SIV]/[SIII] (10.5μm/18.7μm) line ratios are consistent with an ionizing radiation field with an effective temperature of ≈ 41000 K. Comparison of the observed fine-structure line ratios with theoretical models of nebular emission from evolving starbursts shows that stars with masses ≥ 50 M⊙ have been forming recently in NGC 3256. The H2 observations reveal the presence of warm molecular gas. We estimate that ≈ 109 M⊙ of H2 gas is present at temperatures close to 150 K. This mass corresponds to a few percent of the total cold molecular mass as estimated from CO studies.",

keywords = "Galaxies: individual (NGC 3256), Galaxies: interactions, Galaxies: starburst, Infrared: galaxies",

author = "D. Rigopoulou and D. Lutz and R. Genzel and E. Egarai and D. Kunze and E. Sturm and H. Feuchtgruber and S. Schaeidt and Bauer, {O. H.} and A. Sternberg and H. Netzer and Moorwood, {A. F.M.} and {De Graauw}, Th",

year = "1996",

month = nov,

day = "10",

language = "אנגלית",

volume = "315",

pages = "L125--L128",

journal = "Astronomy and Astrophysics",

issn = "0004-6361",

publisher = "EDP Sciences",

number = "2",

}

TY - JOUR

T1 - SWS spectroscopy of the starburst galaxy NGC 3256

AU - Rigopoulou, D.

AU - Lutz, D.

AU - Genzel, R.

AU - Egarai, E.

AU - Kunze, D.

AU - Sturm, E.

AU - Feuchtgruber, H.

AU - Schaeidt, S.

AU - Bauer, O. H.

AU - Sternberg, A.

AU - Netzer, H.

AU - Moorwood, A. F.M.

AU - De Graauw, Th

PY - 1996/11/10

Y1 - 1996/11/10

N2 - We present 2.5-40 μm ISO SWS spectra of the starburst galaxy NGC 3256. We have observed many fine-structure lines of various atomic species as well as three rotational transitions of molecular hydrogen. From the [SIII] 18μm/33μm line ratio we infer low electron densities of ≈ 300 cm-3 in the HII regions. The observed [NeIII]/[NeII] (15μm/12μm), [ArIII]/[ArII] (8.9μm/6.9μm), and [SIV]/[SIII] (10.5μm/18.7μm) line ratios are consistent with an ionizing radiation field with an effective temperature of ≈ 41000 K. Comparison of the observed fine-structure line ratios with theoretical models of nebular emission from evolving starbursts shows that stars with masses ≥ 50 M⊙ have been forming recently in NGC 3256. The H2 observations reveal the presence of warm molecular gas. We estimate that ≈ 109 M⊙ of H2 gas is present at temperatures close to 150 K. This mass corresponds to a few percent of the total cold molecular mass as estimated from CO studies.

AB - We present 2.5-40 μm ISO SWS spectra of the starburst galaxy NGC 3256. We have observed many fine-structure lines of various atomic species as well as three rotational transitions of molecular hydrogen. From the [SIII] 18μm/33μm line ratio we infer low electron densities of ≈ 300 cm-3 in the HII regions. The observed [NeIII]/[NeII] (15μm/12μm), [ArIII]/[ArII] (8.9μm/6.9μm), and [SIV]/[SIII] (10.5μm/18.7μm) line ratios are consistent with an ionizing radiation field with an effective temperature of ≈ 41000 K. Comparison of the observed fine-structure line ratios with theoretical models of nebular emission from evolving starbursts shows that stars with masses ≥ 50 M⊙ have been forming recently in NGC 3256. The H2 observations reveal the presence of warm molecular gas. We estimate that ≈ 109 M⊙ of H2 gas is present at temperatures close to 150 K. This mass corresponds to a few percent of the total cold molecular mass as estimated from CO studies.

KW - Galaxies: individual (NGC 3256)

KW - Galaxies: interactions

KW - Galaxies: starburst

KW - Infrared: galaxies

UR - http://www.scopus.com/inward/record.url?scp=0001235123&partnerID=8YFLogxK

M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???

AN - SCOPUS:0001235123

SN - 0004-6361

VL - 315

SP - L125-L128

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

IS - 2

ER -

SWS spectroscopy of the starburst galaxy NGC 3256

Abstract

Keywords

Other files and links

Fingerprint

Cite this