J/A+A/551/A82 Line ratios in giant HII region H 1013 (Stasinska+, 2013)
No temperature fluctuations in the giant HII region H 1013.
Stasinska G., Morisset C., Simon-Diaz S., Bresolin F., Schaerer D.,
Brandl B.
<Astron. Astrophys., 551, A82 (2013)>
=2013A&A...551A..82S 2013A&A...551A..82S
ADC_Keywords: H II regions ; Spectroscopy
Keywords: ISM: abundances - HII regions - galaxies: individual: H 1013
Abstract:
While collisionally excited lines in HII regions allow one to easily
probe the chemical composition of the interstellar medium in galaxies,
the possible presence of important temperature fluctuations casts some
doubt on the derived abundances. To provide new insights into this
question, we have carried out a detailed study of a giant HII region,
H1013, located in the galaxy M101, for which many observational data
exist and which has been claimed to harbour temperature temperature
fluctuations at a level of t2=0.03-0.06.
Description:
Cedres & Cepa (2002, Cat. J/A+A/391/809) used CDD observations in
several narrow-band filters to compile a catalogue of 338 HII regions
in the inner parts of M 101 (NGC 5457), also providing information
about their fluxes, extinctions, equivalent widths, spatial
distribution, excitations, radiation hardness, ionization parameters
and metallicities. H1013 is identified as the HII region number
299 in their catalogue.
We use the Hα and Hβ continuum-subtracted images (kindly
provided by B. Cedres) in our study. These images were obtained at
the Nordic Optical Telescope with the ALFOSC instrument in direct
imaging mode (spatial resolution of 0.189-arcsec/pix).
Objects:
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RA (2000) DE Designation(s)
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14 03 30.8 +54 21 14 H1013 = HGGK 1013
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 48 73 Observed line ratios in H 1013 compared to the
results of models M1 and M2
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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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1- 16 A16 --- Line Line designation
17 A1 --- n_Line [+] multiplet sum (1)
19- 21 A3 --- Ref References (2)
23- 28 F6.2 --- Obs Observed line intensity (3)
30- 34 F5.2 --- e_Obs ? rms uncertainty on Obs (3)
36- 41 F6.2 --- ModM1 Model M1 line intensity (3)
43- 48 F6.2 --- ModM2 Model M2 line intensity (3)
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Note (1): + represents the sum of the multiplet 1 of OII or SII.
Note (2): References as follows:
B07 = Bresolin, 2007ApJ...656..186B 2007ApJ...656..186B
E09 = Esteban, 2009, Cat. J/ApJ/700/654
IR = infrared
Note (3): In units of Hβ=100 for optical lines, or of
H7-6(12.4um)=1 for infrared lines. The last line "logL(Ha)"
gives the Hα luminosity in log(erg/s=10-7W).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Aug-2013