J/A+A/422/511 Oxygen abundance in M101 HII regions (Cedres+, 2004)
The oxygen abundance gradient in M101: the reliability of the P method.
Cedres B., Urbaneja M.A., Cepa J.
<Astron. Astrophys. 422, 511 (2004)>
=2004A&A...422..511C 2004A&A...422..511C
ADC_Keywords: H II regions; Photometry, narrow-band; Abundances;
Keywords: ISM: HII regions - galaxies: individual: M101 - galaxies: abundances
Abstract:
We present the oxygen abundance determination for 90 HII regions in
the inner parts of the grand design galaxy M101. The abundances were
derived employing the P method (Pilyugin, 2001A&A...369..594P 2001A&A...369..594P). A
comparison is made with previous determinations using another
calibration and direct measurements of electron temperature to derive
the oxygen abundance. The results show agreement with the abundances
derived from the electron temperature method and also show that the
older calibration is not as accurate as the P method.
Objects:
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RA (2000) DE Designation(s)
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14 03 12.5 +54 20 53 M 101 = NGC 5457
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 20 221 Region number and derived oxygen abundance for
M101 (NGC 5457)
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See also:
J/A+A/391/809 : HII regions in NGC 5457 and NGC 4395 (Cedres+, 2002)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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4- 6 I3 --- Region Region identification number (1)
10- 13 F4.2 --- 12+log(O/H) Oxygen abundance (H=12)
17- 20 F4.2 --- e_12+log(O/H) Error in the oxygen abundance
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Note (1): The region number is the employed in Cedres & Cepa
(2002, Cat. J/A+A/391/809), [CC2002] NGC 5457 NNN in Simbad
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Acknowledgements: Bernabe Cedres Exposito
(End) Patricia Vannier [CDS] 12-Jul-2004