共查询到20条相似文献,搜索用时 14 毫秒
1.
D. F. Dickinson G. Kojoyan C. R. Purton R. A. Sramek H. M. Tovmassian 《Astronomische Nachrichten》1976,297(6):283-286
Radio spectra of 16 Markarian galaxies are studied between 2.7 and 15.5 GHz. The Seyfert-type galaxies have power-law spectra with an average spectral index of -0.82, except for MRK 348, which is an active galaxy with a complex spectrum. The galaxies with featureless optical spectra have rather flat radio spectra, similar to BL Lac-type objects. 相似文献
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The atomic and molecular hydrogen gas properties of a complete sample of Markarian galaxies with flux density at 60 µm higher than 1.95 Jy are presented. We present the improved far-infrared luminosity function of Markarian galaxies; and its comparison with other samples. We find that 40% of the bright IRAS galaxies of far-infrared luminosity higher than 1010.5
L
are Markarian galaxies. There is an absence of correlation between HI content of Markarian galaxies and current star formation activity, implying that star formation in these systems has complex structure and it is not a simple function of the HI content. On the contrary, the H2 content of Markarian galaxies is well correlated with star formation activity. It is argued that tight correlation between HI and H2 contents is a consequence of transformation of atomic hydrogen into molecular.Published in Astrofizika, Vol. 38, No. 4, pp. 636–644, October–December, 1995. 相似文献
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G. T. Petrov 《Astrophysics and Space Science》1993,199(2):199-213
The IR emission of 640 Markarian galaxies (MrkG), included in the IRAS Survey, is considered as an evidence for enhanced star formation rate (SFR) in these objects. About 73% of the MrkG have high far-infrared luminosities (ca. 10E + 44 erg s–1) in 1–500 mcm IR spectral band. The distribution of log(f
60/f
100), peaked at about 45 K, shows that IRAS MrkGs have a tendency to extend the relationf
60/f
100 vsL
ir/L
bifor normal S glaxies. They emit up to hundred times more IR energy in 40–120 mcm band than in optics. The mean ratio log L
ir/L
b for 621 IRAS MrkG with known redshifts is 2.2.It is suggested that there are two IR emitting components in the IRAS MrkG - a warm one connected with the UV-fluxes of the newborn massive stars, re-radiated by dust, and a cool one, originated from the dust in galactic disks and heated by the general interstellar radiation field. The warm IR luminosities and warm IR fractions are determined on the basis of IR colour-colour diagrams(25/12),(60/25), and(100/60). The mean warm IR fraction for all Mrk IRAS detected galaxies with well-defined IR fluxes is 0.83 when the grain mass absorption coefficient model withn = 0.0 is used. The dust mass responsible for the IR flux at 60 mcm is derived to be about 10E + 5M
, assuming the dust clouds are optically thin, and using the dust temperatureT
d 46 K (deduced from thef(60)/f(100) ratio). There is a relation betweenL
irandL
blwhich points out that the most IRAS MrkG have rather enhanced SFR. 相似文献
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M. A. Kazarian 《Astrophysics》1997,40(2):119-124
The results of a spectroscopic and morphological investigation of galaxies with a UV excess, Nos. 205,206, 208, and 209 from the list of [M. A. Kazarian, Astrofizìka,15, 5 (1979);15, 193 (1979)], are presented. The equivalent widths, relative intensities, and half-widths of lines were determined. The mass of galaxy
No. 205 was also determined.
Translated from Astrofizika, Vol. 40, No. 2, pp. 179–185, April–June, 1997. 相似文献
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The results of morphological and spectral study of the galaxies Kaz 5, Kaz 92, and Kaz 390 are presented. The observations
were made on the 2.6-m telescope at the Byurakan Observatory with the VAGR microlenses spectrograph. Isophotes of the images
of the galaxies are constructed in the Hα, [NII] λλ6584 , 6548, and [SII] λλ6731, 6717 emission lines and in the continuum. The masses of Kaz 5 and Kaz 92 are determined to be 8.6 × 108 M⊙ and 6.1 × 109 M⊙ , respectively. The mass of the gaseous component in the centers of regions I and IV of Kaz 390, which encompass a 1 pixel
area, are also determined. The morphological structure of the central region of Kaz 5 in the observed spectral range, λλ6400–6800?, differs completely from the structure of the same part of the galaxy observed with the 6-m and 2.5-m telescopes. It is shown
that these differences in the structure in images of Kaz 5 are mostly explained by the comparatively low resolution of the
telescope in combination with the VAGR spectrograph. Absorbing matter also contributes to this effect. It is also shown that
a “deficit” of nitrogen has been observed in the region of Kaz 390 studied here (a circle of diameter 40″).
Translated from Astrofizika, Vol. 52, No. 1, pp. 63–74 (February 2009). 相似文献
12.
The results of a spectroscopic investigation of galaxies Nos. 22, 35, 133, 317, and 321 from the lists of [M. A. Kazarian,
Astrofizika,15, 5 (1979); M. A. Kazarian and é. S. Kazarian, Astrofizika,16, 17 (1980)] are given. The equivalent widths of lines, the relative intensities of emission lines, and their half-widths
are determined.
Translated from Astrofizika, Vol. 40, No. 4, pp. 619–626, October-December, 1997. 相似文献
13.
Dominic G. B. Edelen 《Astrophysics and Space Science》1969,3(1):56-76
A theory of galactic morphology results from the consideration of isoplethic surfaces in states of geometric equilibrium within the theory of general relativity. In the linearized case, one solves ?2ψ+ρ2ψ=0 on the surface of an oblate spheroid with unit semimajor axis and eccentricity ε. The surface defined by $$x^2 + y^2 + z^2 /(1 - \varepsilon ^2 ) = {\text{exp (}}\psi {\text{)}}$$ are then equilibrium isopleths. The resulting morphological system contains two continuous parameters (ε and the norm of ψ) and an integer-valued parametern. The system includes the ellipticals as special cases, and the various available profiles are given for a variety of values of the parameters. The forms are sufficiently varied as to represent NGC 3115, 128, 7332, and IC 3973. These forms cease to be enigmatic for they fit into an orderly sequence progressing out of the ellipticals and have equilibrium interpretations as previously obtained only for the ellipticals. 相似文献
14.
M. A. Kazarian 《Astrophysics》1993,36(3):217-221
Erevan State University. Translated from Astrofizika, Vol. 36, No. 3, pp. 353–361, July–September, 1993. 相似文献
15.
B.M. Poggianti 《Astrophysics and Space Science》2003,285(1):121-131
In this review I focus on the galactic properties in clusters atz>0.1–02. The most salient results regarding the evolution in galaxy colors, spectral features and morphologies are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Static Friedmann-Robertson-Walker vacuum models are derived in the scale-covariant theory. Specific functional forms are obtained for the gauge function which occurs in the theory. This is in contrast to the nonstatic vacuum solutions where the gauge function is arbitrary. 相似文献