The OTELO survey: Revealing a population of low-luminosity active star-forming galaxies at z~0.9

We have performed high resolution VLA radio observations for several small H II regions, including the cluster emission nebulae S258, S255, S257, and S256. The region (PP56) between S255 and S257 at λ2 cm reveals significant flux structure close to OH, H2O and infrared emitting sources as shown in Figure 1. The flux densities and positions are indicated in Table 1. Observations of the cometary nebula PP59 (S269) also reveal similar characteristics as shown in Figure 2. These regions are considered to be active star-forming clouds. The cometary nebula PP40 was also observed and we note that its physical parameters are very similar to those of a typical planetary nebula.

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A multifrequency study of the active star forming region NGC 6357

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307001883 ◽

2006 ◽

Vol 2 (S237) ◽

pp. 400-400

Author(s):

C. E. Cappa ◽

R. H. Barbá ◽

M. Arnal ◽

N. Duronea ◽

E. Fernández Lajús ◽

...

Keyword(s):

Angular Resolution ◽

Massive Stars ◽

Radio Continuum ◽

Large Array ◽

Schmidt Telescope ◽

Ionized Gas ◽

Very Large Array ◽

Active Star ◽

Star Forming ◽

Spiral Arm

To investigate the interaction of the massive stars with the gas and dust in the active star forming region NGC 6357, located in the Sagittarius spiral arm at a distance of 1.7-2.6 kpc (Massey et al. 2001), we analyzed the distribution of the neutral and ionized gas, and that of the dust, based on Hα, [OIII] and [SII] images obtained with the Curtis-Schmidt telescope at CTIO, radio continuum observations at 1.465 MHz obtained with the Very Large Array (NRAO) in the DnC configuration (synthesized beam = 38″), Hi data from the Parkes survey (angular resolution = 15′), CO(1-0) observations obtained with the Nanten radiotelescope at Las Campanas Observatory (angular resolution = 2.7′), and IR images in the four MSX bands (angular resolution = 18.3″).

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ACTIVE STAR-FORMING GALAXIES IN PAIRS IN THE 2DF

Thinking, Observing and Mining the Universe ◽

10.1142/9789812702999_0049 ◽

2004 ◽

Author(s):

G. SORRENTINO ◽

B. KELM ◽

P. FOCARDI

Keyword(s):

Active Star ◽

Star Forming

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A search for Wolf-Rayet stars in active star forming regions of low mass galaxies - GR8, NGC 2366, IC 2574, and NGC 1569

The Astronomical Journal ◽

10.1086/116739 ◽

1993 ◽

Vol 106 ◽

pp. 1460 ◽

Cited By ~ 17

Author(s):

Laurent Drissen ◽

Jean-Rene Roy ◽

Anthony F. J. Moffat

Keyword(s):

Active Star ◽

Star Forming ◽

Star Forming Regions ◽

Low Mass ◽

Ngc 1569

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Diffuse star-forming galaxies: thermal emission in radio continuum at 1.4 GHz

Bulletin of Taras Shevchenko National University of Kyiv Astronomy ◽

10.17721/btsnua.2018.58.21-23 ◽

2018 ◽

pp. 21-23

Author(s):

S. Parnovsky ◽

I. Izotova

Keyword(s):

Star Formation ◽

Radio Emission ◽

Emission Line ◽

Equivalent Width ◽

Colour Index ◽

Thermal Component ◽

Active Star ◽

Star Forming ◽

Active Star Formation ◽

Thermal Radio Emission

We determine the fraction of thermal radio emission in the total flux at the frequency of 1.4 GHz in 30 diffuse star-forming galaxies using the approach described in the paper by Parnovsky and Izotova (Astronomische Nachrichten, 2015 Vol.336, Issue 3, p.276). We use the sample of diffuse galaxies with active star formation selected from the Data Release 12 (DR12) of the Sloan Digital Sky Survey (SDSS). The SDSS spectroscopic data for diffuse galaxies were supplemented by radio data from the FIRST and NVSS catalogues. From the fluxes in the Hβ emission line corrected for extinction and aperture we estimate the fluxes of thermal component of the radio emission at the 1.4 GHz using the result of the paper by J. Caplan and L. Deharveng (Astron. Astrophys. 1986, V. 155, P.297) and compare them with total fluxes from the FIRST and NVSS. In the sample of diffuse galaxies with active star formation, the distribution of the fraction of thermal radio emission A is similar to the lognormal one with the median value of 6 %. This is less than the median value which was derived earlier by Parnovsky and Izotova for a sample of compact star-forming galaxies, but both distributions of A are similar. We study the dependence of A on the W equivalent width of the Hβ emission line and on the I colour index g-r. The fraction of thermal component increases with increasing of the equivalent width of the Hβ emission line if a colour index is constant or an increasing of the colour index at a fixed equivalent width W.

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THE CO(J=2-1)/CO(J=1-0) Luminosity Ratio in the Orion Giant Molecular Clouds

International Astronomical Union Colloquium ◽

10.1017/s0252921100019564 ◽

1994 ◽

Vol 140 ◽

pp. 232-233

Author(s):

Seiichi Sakamoto ◽

Tetsuo Hasegawa ◽

Masahiko Hayashi ◽

Toshihiro Handa ◽

Tomoharu Oka

Keyword(s):

Molecular Clouds ◽

Giant Molecular Clouds ◽

Large Area ◽

Active Star ◽

Star Forming ◽

Star Forming Regions ◽

First Results ◽

Galaxies Active

AbstractThe first results of large-area mapping observations of nearby giant molecular clouds in the CO(J=2-1) emission are presented. The CO(J=2-1)/CO(J=1-0) luminosity ratio is 0.75 and 0.62 for the Orion A and B clouds, respectively. These values are consistent with those observed typically in disks of galaxies (−0.6), and are significantly lower than large values (≳1) often observed in active star-forming regions in galaxies. Active star-forming regions in galaxies cannot be explained by ensemble of Orion-like GMCs; they may contain a different population of molecular clouds with high J-2-1/J=1-0 luminosity ratio.

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