J/AJ/141/113 HII regions of M51 and NGC 4449 (Gutierrez+, 2011)
Properties of the HII region populations of M51 and NGC 4449 from Hα
images with the Advanced Camera for Surveys on the Hubble Space Telescope.
Gutierrez L., Beckman J.E., Buenrostro V.
<Astron. J., 141, 113 (2011)>
=2011AJ....141..113G 2011AJ....141..113G
ADC_Keywords: Galaxies, nearby ; H II regions ; Morphology
Keywords: galaxies: structure - H II regions - ISM: general
Abstract:
We have used images from the Advanced Camera for Surveys on the Hubble
Space Telescope in Hα, and in the neighboring continuum, to
produce flux-calibrated images of the large spiral galaxy M51 and the
dwarf irregular NGC 4449. From these images, we have derived the
absolute luminosities in Hα, the areas, and the positions with
respect to the galactic centers as reference points of over 2600 HII
regions in M51 and over 270 HII regions in NGC 4449.
Description:
The images of M51 (NGC 5194) and its companion NGC 5195 were observed
with the wide field camera of the ACS on HST in 2005 January within
the program 10452 (PI: S. Beckwith, Hubble Heritage Team). The
observations consisted of six pointings through two broadband filters:
F555W (close to standard V) and F814W (close to I), and a narrowband
Hα filter, F658N.
The images of NGC 4449 were also taken from the HST archive. They were
taken during 2005 November through the same filters as those used for
M51, within the program GO 10585 (PI: A. Aloisi).
Objects:
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RA (2000) DE Designation(s) (table)
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13 29 52.70 +47 11 42.9 M51 = NGC 5194 (table2)
12 28 11.12 +44 05 36.8 NGC 4449 = UGC 7592 (table3)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 46 2659 Brightest HII regions in M51
table3.dat 40 273 Brightest HII regions in NGC 4449
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Consecutive number in catalog,
<[GBB2011] M51 NNNN> in Simbad
6- 8 I3 --- Rand ? Rand (1992AJ....103..815R 1992AJ....103..815R) catalog number
10- 16 F7.2 arcsec oRA Right Ascension offset from M51 center
18- 24 F7.2 arcsec oDE Declination offset from M51 center
26- 31 F6.4 arcsec ARad Equivalent HII region angular radius; see text
33- 37 F5.1 pc PRad Equivalent HII region physical radius; see text
39- 46 F8.5 10+31W Lum Luminosity in 10+38erg/s (1)
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Note (1): Assuming 8.4Mpc as the distance to the galaxy M51.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Consecutive number in catalog,
<[GBB2011] NGC4449 NNN> in Simbad
5- 10 F6.2 arcsec oRA Right Ascension offset from NGC 4449 center
12- 18 F7.2 arcsec oDE Declination offset from NGC 4449 center
20- 25 F6.4 arcsec ARad Equivalent HII region angular radius; see text
27- 31 F5.2 pc PRad Equivalent HII region physical radius; see text
33- 40 F8.5 10+31W Lum Luminosity in 10+38erg/s (1)
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Note (1): Assuming 3.82Mpc as the distance to the galaxy NGC 4449.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 01-Aug-2012