UBVR CCD photometry of the spiral galaxy NGC 2903

1990 ◽  
Vol 102 ◽  
pp. 1263 ◽  
Author(s):  
Paul Hodge ◽  
Eric Jaderlund ◽  
Mike Meakes
Keyword(s):  
2002 ◽  
Vol 46 (9) ◽  
pp. 712-720 ◽  
Author(s):  
A. S. Gusev ◽  
S. S. Kaisin
Keyword(s):  

2018 ◽  
Vol 15 (35) ◽  
pp. 8-13
Author(s):  
Sinan H. Ali

The goal of our study is to perform detailed multiband surface photometry of the spiral galaxy NGC 4448 and its brightest star-forming regions. The structure and composition of the stellar population in the surface brightness galaxy NGC 4448 was studied using BVR CCD photometry. The observations were obtained on the 1.88 m optical telescope of Kottamia Astronomical Observatory (KAO), Egypt. A two-dimensional decomposition of the galaxy bulge and disk components is carried out. A powerful star forming region is observed near the galactic center. Based on the positions of the various components of the galaxy in two color diagrams. From the observations, the surface brightness profiles, Ellipticity profiles, position angle profiles and color indices profiles are described and studied.


2004 ◽  
Vol 48 (8) ◽  
pp. 611-621 ◽  
Author(s):  
A. S. Gusev ◽  
S. S. Kaisin

1997 ◽  
Vol 486 (2) ◽  
pp. 681-686 ◽  
Author(s):  
Ariyeh H. Maller ◽  
Ricardo A. Flores ◽  
Joel R. Primack

2011 ◽  
Vol 737 (1) ◽  
pp. 22 ◽  
Author(s):  
Michael E. Anderson ◽  
Joel N. Bregman
Keyword(s):  

2020 ◽  
Vol 499 (4) ◽  
pp. 5163-5174
Author(s):  
A Juráňová ◽  
N Werner ◽  
P E J Nulsen ◽  
M Gaspari ◽  
K Lakhchaura ◽  
...  

ABSTRACT X-ray emitting atmospheres of non-rotating early-type galaxies and their connection to central active galactic nuclei have been thoroughly studied over the years. However, in systems with significant angular momentum, processes of heating and cooling are likely to proceed differently. We present an analysis of the hot atmospheres of six lenticulars and a spiral galaxy to study the effects of angular momentum on the hot gas properties. We find an alignment between the hot gas and the stellar distribution, with the ellipticity of the X-ray emission generally lower than that of the optical stellar emission, consistent with theoretical predictions for rotationally supported hot atmospheres. The entropy profiles of NGC 4382 and the massive spiral galaxy NGC 1961 are significantly shallower than the entropy distribution in other galaxies, suggesting the presence of strong heating (via outflows or compressional) in the central regions of these systems. Finally, we investigate the thermal (in)stability of the hot atmospheres via criteria such as the TI- and C-ratio, and discuss the possibility that the discs of cold gas present in these objects have condensed out of the hot atmospheres.


1997 ◽  
Vol 180 ◽  
pp. 365-365
Author(s):  
B. E. Reddy ◽  
M. Parthasarathy

CCD imaging and BVRI photometry of 14 IRAS sources with far-IR colours similar to planetary nebulae and post-AGB stars are presented. Also results of optical and near-IR spectroscopy of 10 of these candidates are given. Based on the spectral energy distribution from 0.4 μm to 100 μm, the sample of program stars are put into two groups. The sources IRAS 08187-1905, IRAS 05238-0626 and IRAS 17086-2403 present similar flux distributions. These three sources have detached cold dust components with dust radii Rd ≈ 1000 R∗. The low infrared variability of theses sources suggests that the intense mass loss has been ceased. All three sources are at high galactic latitude (1>9°) suggesting that these are old low-mass evolved stars. In the IRAS colour-colour diagram of Likkel et al (1991) these sources fall in the region where most of the stars are evolved stars and PNe but without CO detection. This is consistent with at least one source IRAS 17086-2403, in which OH and CO molecular features are not detected. The far-IR excess, non-variability and high latitude of these objects suggest that these are post-AGB supergiants, slowly evolving towards planetary nebula phase.


1986 ◽  
Vol 64 (4) ◽  
pp. 531-535 ◽  
Author(s):  
Nebojsa Duric ◽  
E. R. Seaquist

Very large array, radio-continuum observations of the edge-on spiral galaxy NGC 3079 are presented. The observations reveal that the nucleus has windlike properties and that the central region of the galaxy exhibits an unusual figure-eight morphology that shows evidence of severe depolarization and a flattening spectral index away from the nucleus. A qualitative description of a model is presented to account for the observed radio properties. It is shown that a wind-driven shock propagating away from the nucleus and focused by the ambient disk gas can give rise to the observed morphology.


Astrophysics ◽  
2007 ◽  
Vol 50 (4) ◽  
pp. 426-439 ◽  
Author(s):  
A. A. Hakobyan ◽  
A. R. Petrosian ◽  
A. A. Yeghazaryan ◽  
J. Boulesteix
Keyword(s):  

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