J/MNRAS/424/2316 Abundances in HII regions (Pilyugin+, 2012)
'Counterpart' method for abundance determinations in HII regions.
Pilyugin L.S., Grebel E.K., Mattsson L.
<Mon. Not. R. Astron. Soc., 424, 2316-2329 (2012)>
=2012MNRAS.424.2316P 2012MNRAS.424.2316P
ADC_Keywords: H II regions ; Abundances
Keywords: ISM: abundances - H II regions - galaxies: abundances
Abstract:
We suggest a new way of determining abundances and electron
temperatures in HII regions from strong emission lines. Our
approach is based on the standard assumption that HII regions with
similar intensities of strong emission lines have similar physical
properties and abundances. A 'counterpart' for a studied HII
region may be chosen among HII regions with well-measured
abundances (reference HII regions) by comparison of carefully
chosen combinations of strong-line intensities. Then the abundances in
the investigated HII region can be assumed to be the same as those
in its counterpart. In other words, we suggest to determine the
abundances in HII regions 'by precedent'. To get more reliable
abundances for the considered HII region, a number of reference
HII regions are selected and then the abundances in the target
HII region are estimated through extrapolation/interpolation. We
will refer to this method of abundance determination as the
counterpart method or, for brevity, the C method. We define a sample
of reference HII regions and verify the validity of the C method.
We find that this method produces reliable abundances. Finally, the C
method is used to obtain the radial abundance distributions in the
extended discs of the spiral galaxies M83, NGC 4625 and NGC 628.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 73 414 List of the reference HII regions
refs.dat 66 93 Reference
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See also:
J/A+AS/91/285 : HII galaxies spectrophotometric catalogue (Terlevich+, 1991)
J/AJ/116/2805 : HII regions in spiral galaxies (Van Zee+, 1998)
J/AJ/121/169 : Imaging and spectroscopy of Tol 1214-277 (Fricke+, 2001)
J/A+A/421/539 : VLT spectroscopy of Tol 1214-277 + Tol 65 (Izotov+, 2004)
J/ApJ/602/200 : HII regions abundances in blue compact galaxies (Izotov+ 2004)
J/ApJ/602/200 : HII regions abundances in blue compact galaxies (Izotov+ 2004)
J/A+A/441/981 : HII regions in 5 spiral galaxies (Bresolin+, 2005)
J/ApJ/636/214 : HII regions in dwarf irregular galaxies (van Zee+, 2006)
J/ApJ/656/168 : Spectrophotometry in NGC 5253 (Lopez-Sanchez+, 2007)
J/A+A/464/885 : Abundances in 53 HII regions (Guseva+, 2007)
J/A+A/476/89 : HII galaxies narrow-band Hbeta images (Lagos+, 2007)
J/ApJ/662/15 : Abundances in extragalactic HII regions (Izotov+, 2007)
J/ApJ/700/654 : Keck spectroscopy of extragalactic HII regions (Esteban+ 2009)
J/A+A/521/A3 : Abundances in HII regions and PNe of M81 (Stanghellini+, 2010)
J/A+A/529/A149 : HII regions in low-metallicity galaxies (Guseva+, 2011)
J/A+A/533/A25 : VLT/X-shooter observations of PHL293B (Izotov+ 2011)
J/ApJ/735/71 : Oxygen abundances in outlying HII regions (Werk+, 2011)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequential number
5- 10 F6.3 [-] logR3 Dereddened [OIII] line intensity R3,
I([OIII]4959,5007)/I(Hβ)
12- 17 F6.3 [-] logR2 Dereddened [OII] line intensity R2,
I([OII]3727,3729)/I(Hβ)
19- 24 F6.3 [-] logN2 Dereddened [NII] line intensity N2,
I([NII]6548,6584)/I(Hβ)
26- 31 F6.3 [-] logS2 Dereddened [SII] line intensity S2,
I([SII]6717,6731)/I(Hβ)
33- 36 F4.2 --- eps(O) Te-based oxygen abundance 12+log(O/H)
38- 41 F4.2 --- eps(N) Te-based nitrogen abundance 12+log(N/H)
43- 46 F4.2 10+4K Te Electron temperature reduced to t3([OIII])
48 I1 --- n_Te [1/3] method to derive Te (jT index) (1)
50- 71 A22 --- HII HII region name
72- 73 I2 --- Ref Reference for spectral data, in refs.dat file
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Note (1): jT index values as follows:
1 = electron temperature is derived from the auroral and nebular [OIII] lines
2 = temperature is derived from the lines of [NII]
3 = temperature is derived from the lines of [SIII]
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 46 A23 --- Aut Author's name
48- 66 A19 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-May-2013