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1571. HII region catalogue of NGC 3359
ID:
ivo://CDS.VizieR/J/A+A/354/823
Title:
HII region catalogue of NGC 3359
Short Name:
J/A+A/354/823
Date:
21 Oct 2021
Publisher:
CDS
Description:
From an H-{alpha} image of the spiral barred galaxy NGC 3359, an HII region catalogue is composed. The catalogue comprises the position, mean radius and the calibrated H-alpha luminosity of each HII region. The observations of the image of NGC 3359 in H-{alpha} were carried out in February 1996, on the Isaac Newton telescope in La Palma in the context of the BARS international time project of the Canary Islands Observatories. A CCD TeK-7 detector was used with a projected pixel size of 0.59".
1572. HII regions in dwarf irregular galaxies
ID:
ivo://CDS.VizieR/J/ApJ/636/214
Title:
HII regions in dwarf irregular galaxies
Short Name:
J/ApJ/636/214
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present long-slit optical spectroscopy of 67 HII regions in 21 dwarf irregular galaxies to investigate the enrichment of oxygen, nitrogen, neon, sulfur, and argon in low-mass galaxies. Oxygen abundances are obtained via direct detection of the temperature-sensitive emission lines for 25 HII regions; for the remainder of the sample, oxygen abundances are estimated from strong-line calibrations. The direct abundance determinations are compared to the strong-line abundance calibrations of both McGaugh (1991ApJ...380..140M) and Pilyugin (2000A&A...362..325P).
1573. HII regions in NGC 628
ID:
ivo://CDS.VizieR/J/A+A/466/905
Title:
HII regions in NGC 628
Short Name:
J/A+A/466/905
Date:
21 Oct 2021
Publisher:
CDS
Description:
Properties of HII region populations in spiral galaxies provide important information about the physics of star formation as well as regional turbulent motions in the interstellar medium. We present a set of 376 photometrically calibrated HII regions in the nearby late-type spiral galaxy NGC 628. We have studies the mean velocity and velocity dispersion for the H-alpha-emitting gas in NGC 628 and found with widely distributed star formation in the disc plane. The H-alpha emission from the HII regions dominates any emission from the diffuse component in this galaxy.
1574. HII regions in NGC 6384
ID:
ivo://CDS.VizieR/J/other/Ap/50.426
Title:
HII regions in NGC 6384
Short Name:
J/other/Ap/50.42
Date:
21 Oct 2021
Publisher:
CDS
Description:
The galaxy NGC6384 has been observed with an IPCS through H{alpha} and [NII] narrow-band interference filters for direct imagery with the 2.6-m Byurakan telescope. We studied the main physical parameters of the identified 98 HII regions, their diameter and luminosity functions, as well the [NII]/H{alpha} ratio distribution.
1575. HII regions in NGC 6814
ID:
ivo://CDS.VizieR/J/AJ/106/56
Title:
HII regions in NGC 6814
Short Name:
J/AJ/106/56
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new Halpha image of high quality of the grand-design galaxy NGC 6814, and describe statistical properties of the HII region population. We have determined positions, angular sizes, and calibrated fluxes of 735 individual HII regions. We construct luminosity functions (LFs) for the complete sample, separately for arm and interarm regions, and for HII regions within and outside the limiting radius corresponding to the bright optical disk. The slope of the LF for the complete sample agrees well with values published for other Sbc and Sc galaxies. LFs for HII regions in the arms, in the interarm regions, in the inner part, and in the outer part of the galaxy all have the same slopes. We show and discuss the diameter distribution of the HII regions, both for the complete sample and for the separate arm, interarm, inner, and outer disk samples. There is no evidence for a different population of HII regions in the spiral arms, nor is there evidence for the existence of a significant population of density-bounded HII regions. We discuss implications for massive star forming processes in this galaxy, and discuss possible differences from other grand-design spirals.
1576. HII regions in NGC 5457 and NGC 4395
ID:
ivo://CDS.VizieR/J/A+A/391/809
Title:
HII regions in NGC 5457 and NGC 4395
Short Name:
J/A+A/391/809
Date:
21 Oct 2021
Publisher:
CDS
Description:
Line intensities, visual extinction, abundances and ionization hardness parameter for HII regions in two spiral galaxies are presented. The following galaxies have been observed: NGC 5457 and NGC 4395. In NGC 5457 have been obtained data for 338 regions. In NGC 4395 have been obtained data for 158 regions. For each region position, visual extinction, H-alpha flux, H-alpha equivalent width, H-beta flux, H-beta equivalent width, [OII] flux, [OIII] flux, [SII] flux, [SIII] flux (only for NGC 5457), R23 parameter, oxygen abundance and ionization hardness parameter (only for NGC 5457) are given.
1577. HII regions in OB associations
ID:
ivo://CDS.VizieR/J/PASP/123/649
Title:
HII regions in OB associations
Short Name:
J/PASP/123/649
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the data from the NOAO Local Group Survey, we have measured the H{alpha} fluxes of 291 nebulae associated with 21 of the van den Bergh OB associations. We have combined these data together with six-color HST WFPC2 photometry, in order to identify the most UV-bright stars in the region. The simple purpose of this article is to explore the spatial relationships between these components.
1578. HII regions in 5 spiral galaxies
ID:
ivo://CDS.VizieR/J/A+A/441/981
Title:
HII regions in 5 spiral galaxies
Short Name:
J/A+A/441/981
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained spectroscopic observations from 3600{AA} to 9200{AA} with FORS at the Very Large Telescope for approximately 70 HII regions located in the spiral galaxies NGC 1232, NGC 1365, NGC 2903, NGC 2997 and NGC 5236. These data are part of a project aiming at measuring the chemical abundances and characterizing the massive stellar content of metal-rich extragalactic HII regions. In this paper we describe our dataset, and present emission line fluxes for the whole sample. In 32 HII regions we measure at least one of the following auroral lines: [S II]4072, [N II]5755, [S III]6312 and [O II]7325. From these we derive electron temperatures, as well as oxygen, nitrogen and sulphur abundances, using classical empirical methods (both so-called "Te-based methods" and "strong line methods"). Under the assumption that the temperature gradient does not introduce severe biases, we find that the most metal-rich nebulae with detected auroral lines are found at 12+log(O/H)~8.9, i.e. about 60% larger than the adopted solar value. However, classical abundance determinations in metal-rich HII regions may be severely biased and must be tested with realistic photoionization models. The spectroscopic observations presented in this paper will serve as a homogeneous and high-quality database for such purpose.
1579. H II regions in spiral galaxies
ID:
ivo://CDS.VizieR/J/AJ/116/2805
Title:
H II regions in spiral galaxies
Short Name:
J/AJ/116/2805
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of low-dispersion optical spectroscopy of 186 HII regions spanning a range of radius in 13 spiral galaxies. Abundances for several elements (oxygen, nitrogen, neon, sulfur, and argon) were determined for 185 of the HII regions. As expected, low metallicities were found for the outlying HII regions of these spiral galaxies. Radial abundance gradients were derived for the 11 primary galaxies; similar to results for other spiral galaxies, the derived abundance gradients are typically -0.04 to -0.07dex/kpc.
1580. HII regions of M33. II.
ID:
ivo://CDS.VizieR/J/PASP/111/685
Title:
HII regions of M33. II.
Short Name:
J/PASP/111/685
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have identified a total of 1272 newly recognized emission regions in M33. Combined with the previously cataloged total of 1066 H II regions and supernova remnants, this brings M33's total to 2338 emission regions. This paper provides photometry of the new objects in H{alpha}, which is combined with data from previous catalogs to produce a global H II region luminosity function (corrected for incompleteness) that reaches a faint luminosity limit of 2x10^34^ergs/s and shows a broad maximum with a peak frequency at luminosities of 6x10^35^ergs/s. We also plot the H II region size distribution and comment on unusual morphologies.