ISOCAM observations of NGC 6946: Mid-IR structure

S. Malhotra; G. Helou; D. Van Buren; M. Kong; C. A. Beichman; H. Dinerstein; D. J. Hollenbach; D. A. Hunter; K. Y. Lo; S. D. Lord; N. Y. Lu; R. H. Rubin; G. J. Stacey; H. A. Thronson; M. W. Werner

ISOCAM observations of NGC 6946: Mid-IR structure

S. Malhotra, G. Helou, D. Van Buren, M. Kong, C. A. Beichman, H. Dinerstein, D. J. Hollenbach, D. A. Hunter, K. Y. Lo, S. D. Lord, N. Y. Lu, R. H. Rubin, G. J. Stacey, H. A. Thronson, M. W. Werner

Arizona State University

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

18 Scopus citations

Abstract

The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7z″resolution and sub-MJy sr^-1 sensitivity. Images taken with CAM filters LW2 (7/μm) and LW3 (15μm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponential disk with a scale length 15″. This is 60 % of the scale length in the optical R-band and radio continuum. The nuclear starburst region is too bright for reliable measurement in these images. Its surface brightness exceeds the inner disk by at least a factor of 12. The arms and interarm regions are clearly detected, with each of these components contributing about equally to the disk emission. The arm-interarm contrast is 2-4 in the mid-IR, close to that measured in the visible R band light and lower than the contrast in H α, suggesting that non-ionizing radiation contributes significantly to dust heating.

Original language	English (US)
Pages (from-to)	L161-L164
Journal	Astronomy and Astrophysics
Volume	315
Issue number	2
State	Published - Nov 10 1996

Keywords

Galaxies: ISM
Galaxies: spiral
Galaxies: structure
Infrared: ISM: continuum
Infrared: galaxies

ASJC Scopus subject areas

Astronomy and Astrophysics
Space and Planetary Science

Cite this

@article{1890827b77e44019b461ba1a15c9284f,

title = "ISOCAM observations of NGC 6946: Mid-IR structure",

abstract = "The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7z″resolution and sub-MJy sr-1 sensitivity. Images taken with CAM filters LW2 (7/μm) and LW3 (15μm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponential disk with a scale length 15″. This is 60 % of the scale length in the optical R-band and radio continuum. The nuclear starburst region is too bright for reliable measurement in these images. Its surface brightness exceeds the inner disk by at least a factor of 12. The arms and interarm regions are clearly detected, with each of these components contributing about equally to the disk emission. The arm-interarm contrast is 2-4 in the mid-IR, close to that measured in the visible R band light and lower than the contrast in H α, suggesting that non-ionizing radiation contributes significantly to dust heating.",

keywords = "Galaxies: ISM, Galaxies: spiral, Galaxies: structure, Infrared: ISM: continuum, Infrared: galaxies",

author = "S. Malhotra and G. Helou and {Van Buren}, D. and M. Kong and Beichman, {C. A.} and H. Dinerstein and Hollenbach, {D. J.} and Hunter, {D. A.} and Lo, {K. Y.} and Lord, {S. D.} and Lu, {N. Y.} and Rubin, {R. H.} and Stacey, {G. J.} and Thronson, {H. A.} and Werner, {M. W.}",

year = "1996",

month = nov,

day = "10",

language = "English (US)",

volume = "315",

pages = "L161--L164",

journal = "Astronomy and Astrophysics",

issn = "0004-6361",

publisher = "EDP Sciences",

number = "2",

}

TY - JOUR

T1 - ISOCAM observations of NGC 6946

T2 - Mid-IR structure

AU - Malhotra, S.

AU - Helou, G.

AU - Van Buren, D.

AU - Kong, M.

AU - Beichman, C. A.

AU - Dinerstein, H.

AU - Hollenbach, D. J.

AU - Hunter, D. A.

AU - Lo, K. Y.

AU - Lord, S. D.

AU - Lu, N. Y.

AU - Rubin, R. H.

AU - Stacey, G. J.

AU - Thronson, H. A.

AU - Werner, M. W.

PY - 1996/11/10

Y1 - 1996/11/10

N2 - The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7z″resolution and sub-MJy sr-1 sensitivity. Images taken with CAM filters LW2 (7/μm) and LW3 (15μm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponential disk with a scale length 15″. This is 60 % of the scale length in the optical R-band and radio continuum. The nuclear starburst region is too bright for reliable measurement in these images. Its surface brightness exceeds the inner disk by at least a factor of 12. The arms and interarm regions are clearly detected, with each of these components contributing about equally to the disk emission. The arm-interarm contrast is 2-4 in the mid-IR, close to that measured in the visible R band light and lower than the contrast in H α, suggesting that non-ionizing radiation contributes significantly to dust heating.

AB - The nearby spiral galaxy NGC 6946 was observed with ISO-CAM in the mid-infrared, achieving 7z″resolution and sub-MJy sr-1 sensitivity. Images taken with CAM filters LW2 (7/μm) and LW3 (15μm) are analysed to determine the morphology of this galaxy and understand better the emission mechanisms. The mid-infrared emission follows an exponential disk with a scale length 15″. This is 60 % of the scale length in the optical R-band and radio continuum. The nuclear starburst region is too bright for reliable measurement in these images. Its surface brightness exceeds the inner disk by at least a factor of 12. The arms and interarm regions are clearly detected, with each of these components contributing about equally to the disk emission. The arm-interarm contrast is 2-4 in the mid-IR, close to that measured in the visible R band light and lower than the contrast in H α, suggesting that non-ionizing radiation contributes significantly to dust heating.

KW - Galaxies: ISM

KW - Galaxies: spiral

KW - Galaxies: structure

KW - Infrared: ISM: continuum

KW - Infrared: galaxies

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M3 - Article

AN - SCOPUS:0009506738

SN - 0004-6361

VL - 315

SP - L161-L164

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

IS - 2

ER -

ISOCAM observations of NGC 6946: Mid-IR structure

Abstract

Keywords

ASJC Scopus subject areas

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