scholarly journals Formaldehyde observations at XAO

2012 ◽  
Vol 8 (S292) ◽  
pp. 62-62
Author(s):  
Gang Wu ◽  
Jarken Esimbek ◽  
Jian-Jun Zhou ◽  
Wei-Guang Ji
Keyword(s):  
Hii Regions ◽  
Galactic Structure ◽  
Astronomical Observatory

AbstractIn recent years our team has performed H2CO(110 − 111) observations towards GMCs and HII regions with the Xinjiang Astronomical Observatory, CAS. Here, we provide a summary of these observations. More than 200 new formaldehyde sources are detected, 8 extended GMC have been mapped, kinetic distances, Galactic structure and a related discussion are provided.

Constraining the Galactic Structure with Stellar Clusters in Obscured Hii Regions

2009 ◽  
pp. 321-326
Author(s):  
M. Messineo ◽  
M. Petr-Gotzens ◽  
K. M. Menten ◽  
F. Schuller ◽  
H. J. Habing
Keyword(s):  
Hii Regions ◽  
Galactic Structure ◽  
Stellar Clusters

scholarly journals Interpretation of the apparent anomalies of the Galactic structure

1985 ◽  
Vol 106 ◽  
pp. 305-308
Author(s):  
T. Jaakkola ◽  
N. Holsti ◽  
P. Teerikorpi
Keyword(s):  
Spiral Structure ◽  
Neutral Hydrogen ◽  
Hii Regions ◽  
Galactic Structure ◽  
Circular Motion ◽  
The Sun ◽  
The South ◽  
The North ◽  
Perseus Arm ◽  
Strong Curvature

In maps of the galactic structure based on the kinematical method (Fig. 1) several systematically heliocentric anomalies are found: 1. Assuming purely circular motion, the spiral arms are more tightly wound and the extent of neutral hydrogen is smaller in the northern galactic hemisphere than in the southern one. 2. With separate rotation curves for the north and the south, the arms become anomalously circular. 3. Consequently, there is a striking discrepancy with the stellar spiral structure. 4. There are long straight portions in the arms pointing towards the Sun. 5. There are abrupt knee-like features in the south. 6. Some arms seem to affect the structure of other, outer arms. 7. Conspicuously strong curvature of the arms is found in the north. 8. The HI-density is enhanced at symmetric longitudes on the far side. 9. With the northern rotation model HII-regions and HI avoid the southern tangential circle. 10. The Perseus Arm is displaced at 1 = 180°.

scholarly journals Nests of Interacting Galaxies: What is It?

1987 ◽  
Vol 121 ◽  
pp. 579-586
Author(s):  
V.P. Arkhipova ◽  
A.V. Zasov ◽  
R.I. Noskova ◽  
O.K. Silchenko
Keyword(s):  
Star Formation ◽  
Hii Regions ◽  
Velocity Fields ◽  
Astronomical Observatory ◽  
Interacting Galaxies ◽  
Multiple Systems ◽  
Ubv Photometry ◽  
Intense Star Formation

Kinematical and photometric studies of nests of interacting galaxies are described. Velocity fields of 22 nests were obtained using the 6-meter telescope of the Special Astronomical Observatory of Sciences Academy of USSR. UBV-photometry carried out with 125-cm telescope of Sternberg Institute has shown that the majority of nests is blue and undergoes intense star formation. Nests are found to be of different types:among them there are single SB and dwarf Irr galaxies with super-giant HII -regions as well as tight pairs and multiple systems of galaxies. Multiple systems classified as nests are shown to be dynamically stable.

A New Interpretation of the Galactic Structure from HII Regions

1970 ◽  
pp. 209-212 ◽  
Author(s):  
G. Courtès ◽  
Y. P. Georgelin ◽  
Y. M. Georgelin ◽  
G. Monnet
Keyword(s):  
Hii Regions ◽  
Galactic Structure ◽  
New Interpretation

scholarly journals Chemical Composition of Galactic Planetary Nebulae and HII Regions in Blue Compact Dwarf Galaxies: New Determination

2003 ◽  
Vol 209 ◽  
pp. 565-566
Author(s):  
V.V. Holovatyy ◽  
N.V. Havrylova ◽  
B.Ya. Melekh
Keyword(s):  
Chemical Composition ◽  
Dwarf Galaxies ◽  
Planetary Nebulae ◽  
Hii Regions ◽  
Astronomical Observatory ◽  
Atomic Data ◽  
Correction Factors ◽  
Hii Region ◽  
National University

The expressions of new ionization-correction factors (ICF) (see these Proceedings) are employed for the determination of chemical composition of the 200 galactic planetary nebulae(PN) and 43 HII regions in blue compact dwarf galaxies (BCDG). We have used PN spectra from different papers published previously (> 100) and HII region spectra from (Izotov, Thuan, & Lipovetsky 1.994, Izotov, Thuan, & Lipovetsky 1997, Thuan, Izotov, & Lipovetsky hys. J. 1995). Code DIAGN (Holovatyy et al. 1999) developed at Astronomical Observatory of Lviv National University is also used. Atomic data for determination of ne, Te and the ionic abundances (A+i/H+) were modified to be compatible with the CLOUDY94 code (Ferland G.J. 1999).

scholarly journals Optical observations of the nearby galaxy IC342 with narrow band [SII] and Hα filters. I

2013 ◽  
pp. 11-18 ◽  
Author(s):  
M.M. Vucetic ◽  
B. Arbutina ◽  
D. Urosevic ◽  
A. Dobardzic ◽  
M.Z. Pavlovic ◽  
...  
Keyword(s):  
Spiral Galaxy ◽  
Narrow Band ◽  
Hii Regions ◽  
Astronomical Observatory ◽  
Optical Observations ◽  
Nearby Galaxy ◽  
The Galaxy

We present observations of a portion of the nearby spiral galaxy IC342 using narrow band [SII] and H? filters. These observations were carried out in November 2011 with the 2m RCC telescope at Rozhen National Astronomical Observatory in Bulgaria. In this paper we report coordinates, diameters, H? and [SII] fluxes for 203 HII regions detected in two fields of view in IC342 galaxy. The number of detected HII regions is 5 times higher than previously known in these two parts of the galaxy.

scholarly journals Determination of Galactic spiral structure at radiofrequencies

1985 ◽  
Vol 106 ◽  
pp. 283-300 ◽  
Author(s):  
H. S. Liszt
Keyword(s):  
Spiral Structure ◽  
Hii Regions ◽  
Galactic Structure ◽  
Spiral Pattern ◽  
Galactic Spiral Structure ◽  
Galactic Spiral ◽  
Adequate Method

We consider some results of attempts to trace the pattern of galactic spiral structure in HII regions, HI, and CO. There is really no adequate method available for solving this problem, a fact reflected in the lack of consensus regarding the “correct” spiral pattern. The newly-begun process of deriving galactic structure in CO seems to be recapitulating the history laid down by HI observers.

Calibration problems in hydrogen luminosities

1966 ◽  
Vol 24 ◽  
pp. 322-330
Author(s):  
A. Beer
Keyword(s):  
Galactic Structure ◽  
B Stars ◽  
Insight Into

The investigations which I should like to summarize in this paper concern recent photo-electric luminosity determinations of O and B stars. Their final aim has been the derivation of new stellar distances, and some insight into certain patterns of galactic structure.

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