Analysis and models of photoionized structures seen in Hubble Space Telescope images of NGC 7635

Brian D. Moore, J. Jeff Hester, Paul Scowen, Donald K. Walter

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

We present the analysis of photoionized structures seen in Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 7635 and the surrounding H II region S162. We exploit the high spatial resolution images to make a census of the total ionizing flux from the O6.5 IIIf star BD +60°2522. We also construct detailed models of two structures with a photoionization code, reproducing the line emission seen in spatial profiles extracted directly from the images. We demonstrate that the density distribution of the models produces deviations in the spectrally derived elemental abundances at a level exceeding typical observational errors. Our results also show a large discrepancy between the star's effective temperature used for our best-fit models (34,320 K) and that expected based on its spectral type (>40,000 K) from a hot-star calibration taken from the literature. We suggest that this is due to the use of plane-parallel stellar atmospheres in constructing that calibration.

Original languageEnglish (US)
Pages (from-to)3305-3312
Number of pages8
JournalAstronomical Journal
Volume124
Issue number6 1764
DOIs
StatePublished - Dec 1 2002

Fingerprint

Hubble Space Telescope
calibration
stars
census
stellar atmospheres
hot stars
H II regions
density distribution
photoionization
spatial resolution
cameras
deviation
atmosphere
high resolution
profiles
analysis
temperature

Keywords

  • H II regions
  • ISM: individual (NGC 7635)
  • ISM: kinematics and dynamics
  • Stars: individual (BD +60°2522)
  • Stars: mass loss

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Analysis and models of photoionized structures seen in Hubble Space Telescope images of NGC 7635. / Moore, Brian D.; Hester, J. Jeff; Scowen, Paul; Walter, Donald K.

In: Astronomical Journal, Vol. 124, No. 6 1764, 01.12.2002, p. 3305-3312.

Research output: Contribution to journalArticle

Moore, Brian D. ; Hester, J. Jeff ; Scowen, Paul ; Walter, Donald K. / Analysis and models of photoionized structures seen in Hubble Space Telescope images of NGC 7635. In: Astronomical Journal. 2002 ; Vol. 124, No. 6 1764. pp. 3305-3312.
@article{0f5dadf014424cc694cbc0a8abebb83f,
title = "Analysis and models of photoionized structures seen in Hubble Space Telescope images of NGC 7635",
abstract = "We present the analysis of photoionized structures seen in Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 7635 and the surrounding H II region S162. We exploit the high spatial resolution images to make a census of the total ionizing flux from the O6.5 IIIf star BD +60°2522. We also construct detailed models of two structures with a photoionization code, reproducing the line emission seen in spatial profiles extracted directly from the images. We demonstrate that the density distribution of the models produces deviations in the spectrally derived elemental abundances at a level exceeding typical observational errors. Our results also show a large discrepancy between the star's effective temperature used for our best-fit models (34,320 K) and that expected based on its spectral type (>40,000 K) from a hot-star calibration taken from the literature. We suggest that this is due to the use of plane-parallel stellar atmospheres in constructing that calibration.",
keywords = "H II regions, ISM: individual (NGC 7635), ISM: kinematics and dynamics, Stars: individual (BD +60°2522), Stars: mass loss",
author = "Moore, {Brian D.} and Hester, {J. Jeff} and Paul Scowen and Walter, {Donald K.}",
year = "2002",
month = "12",
day = "1",
doi = "10.1086/344597",
language = "English (US)",
volume = "124",
pages = "3305--3312",
journal = "Astronomical Journal",
issn = "0004-6256",
publisher = "IOP Publishing Ltd.",
number = "6 1764",

}

TY - JOUR

T1 - Analysis and models of photoionized structures seen in Hubble Space Telescope images of NGC 7635

AU - Moore, Brian D.

AU - Hester, J. Jeff

AU - Scowen, Paul

AU - Walter, Donald K.

PY - 2002/12/1

Y1 - 2002/12/1

N2 - We present the analysis of photoionized structures seen in Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 7635 and the surrounding H II region S162. We exploit the high spatial resolution images to make a census of the total ionizing flux from the O6.5 IIIf star BD +60°2522. We also construct detailed models of two structures with a photoionization code, reproducing the line emission seen in spatial profiles extracted directly from the images. We demonstrate that the density distribution of the models produces deviations in the spectrally derived elemental abundances at a level exceeding typical observational errors. Our results also show a large discrepancy between the star's effective temperature used for our best-fit models (34,320 K) and that expected based on its spectral type (>40,000 K) from a hot-star calibration taken from the literature. We suggest that this is due to the use of plane-parallel stellar atmospheres in constructing that calibration.

AB - We present the analysis of photoionized structures seen in Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 7635 and the surrounding H II region S162. We exploit the high spatial resolution images to make a census of the total ionizing flux from the O6.5 IIIf star BD +60°2522. We also construct detailed models of two structures with a photoionization code, reproducing the line emission seen in spatial profiles extracted directly from the images. We demonstrate that the density distribution of the models produces deviations in the spectrally derived elemental abundances at a level exceeding typical observational errors. Our results also show a large discrepancy between the star's effective temperature used for our best-fit models (34,320 K) and that expected based on its spectral type (>40,000 K) from a hot-star calibration taken from the literature. We suggest that this is due to the use of plane-parallel stellar atmospheres in constructing that calibration.

KW - H II regions

KW - ISM: individual (NGC 7635)

KW - ISM: kinematics and dynamics

KW - Stars: individual (BD +60°2522)

KW - Stars: mass loss

UR - http://www.scopus.com/inward/record.url?scp=0141596057&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0141596057&partnerID=8YFLogxK

U2 - 10.1086/344597

DO - 10.1086/344597

M3 - Article

VL - 124

SP - 3305

EP - 3312

JO - Astronomical Journal

JF - Astronomical Journal

SN - 0004-6256

IS - 6 1764

ER -