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1.
We review selected measurements of the galaxy luminosity function including the field, the local group, the local sphere,
nearby clusters (Virgo, Coma and Fornax) and clusters in general. We conclude that, excluding the super-luminous cD and D
galaxies, the overall cluster luminosity function is fully consistent with the field luminosity function over the magnitude
range in common (–22 ≤ M
B
–5log
h
0.68
≤ –17). We find that only in the core regions of clusters (r ≤ 300 kpc) does the overall form of the luminosity function show significant variation. However when the luminosity function
is subdivided by spectral type some further variations are seen. We argue that these results imply: substantial late infall,
efficient star-formation suppression, and the confinement of mass-changing evolutionary processes to the core regions only.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
The widely varying dwarf galaxy counts in different environments provide a strong challenge to standard hierarchical clustering
models. The luminosity function is not universal, but seems to be strongly dependent upon environment. In this paper we describe
an automated procedure for detecting and measuring very Low Surface Brightness (LSB) features in deep CCD data. We apply this
procedure to large area CCD survey fields of the Virgo cluster and find 105 dwarf LSB galaxies previously uncatalogued over
an area of ∼14 sq deg. We show that there are many more faint (14≤MB≤–10) LSB galaxies than would be predicted from extrapolation of the Virgo cluster catalogue luminosity function. Over our
limited range of measurement the faint end slope of the luminosity function becomesα=–1.6. Although these galaxies contribute
a small fraction of the total stellar light of the cluster, they may contribute significantly to the mass in galaxies if they
have large mass-to-light ratios similar to those recently measured for Local Group dwarf galaxies. By a comparison with different
environments, the Virgo Cluster seems to be highly `dwarf rich' if considering the dwarf to giant ratio or it's luminosity
function faint end slope.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
A. Fritz B.L. Ziegler R.G. Bower I. Smail R.L. Davies 《Astrophysics and Space Science》2003,285(1):61-66
We explore the evolution of the early-type galaxy population in the rich cluster Abell 2390 at z=0.23. For this purpose, we have obtained spectroscopic data of 51 elliptical and lenticular galaxies with MOSCA at the 3.5
m telescope on Calar Alto Observatory. As our investigation spans both a broad range in luminosity (–22.3≤MB≤–:19.3)and a wide field of view (10′×10′), the environmental dependence of different formation scenarios can be analysed
in detail as a function of radius from the cluster center. In this paper, we present first results on the Faber-Jackson relation
and, for a subsample of 14 galaxies with morphological and structural parameters from HST, we also investigate the evolution
of the Kormendy relation and the Fundamental Plane. We find a mild luminosity evolution of the early-type galaxies in Abell
2390: our objects are on average brighter by m
B∼0.4 mag.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
A. P. Mahtessian 《Astrophysics》2011,54(2):162-176
The Schmidt method for constructing the luminosity function of galaxies is generalized to include the dependence of the density
of galaxies on distance in the near universe. The logarithmic luminosity function (LLF) of the field galaxies as a function
of morphological type is constructed. It is found that the LLF for all the galaxies, as well as separately for elliptical
and lenticular galaxies, can be represented as a Schechter function within a narrow range of absolute magnitudes. The LLF
for spiral galaxies is a Schechter function over a rather wide range of absolute magnitudes, −21.0 ≤ M ≤ −14 . The parameter
M* varies little over the spiral galaxies. The parameter α in the Schechter function decreases on going from early to later
spirals. On going from elliptical to lenticular galaxies, from early spiral galaxies and onward to later spiral galaxies,
a decrease in the average luminosity of the galaxies is observed in the bright end, −23 ≤ M ≤ −17.8 . The completeness and
average density of the samples are estimated for galaxies of different morphological types. The average number density of
all the galaxies within the range −23 ≤ M ≤ −13 is 0.126 Mpc-3. 相似文献
5.
A catalog of barred spiral galaxies of types SB and SAB with BT ≤ 13.5 and δ > -10° has been compiled. Some parameters of these galaxies are given.
Translated from Astrofizika, Vol. 4L No. 1, pp. 5–21 January-March. 1998. 相似文献
6.
O. G. Kashibadze 《Astrophysics》2008,51(3):336-348
The peculiar velocity field for 907 galaxies with heliocentric radial velocities VH ≤ 3000 km/s is examined. The data are divided into three samples, organized according to the principles behind the method
for determining the distance to the galaxies: the luminosity of the tip of the red giant branch (TRGB), fluctuations in the
surface brightness, and the infrared Tully-Fisher relation for spiral galaxies viewed edge-on. The latter sample includes
410 galaxies. For determining the distance to the galaxies in this sample, additional regressors were introduced into the
Tully-Fisher relation, in particular the “color index” K-m21, which make it possible significantly to reduce the dispersion with respect to the regression curve. All three samples showed
good agreement in the peculiar velocity distribution. Based on each of these samples, as well as on the combined sample, detailed
maps of the field of peculiar velocities of the galaxies are constructed for VH ≤ 3000 km/s. An analysis shows that most of the observed features of this map can be explained by large-scale density variations
in the galactic distribution.
__________
Translated from Astrofizika, Vol. 51, No. 3, pp. 409–422 (August 2008). 相似文献
7.
We present R-band galaxy luminosity functions (GLFs) from aspectroscopic sample of six nearby rich galaxy clusters. In addition
to individual cluster GLFs, extending to, in one case, M
R=–14, we also present composite GLFs for cluster and field galaxies toM
R=–17. All six cluster samples are consistent with the composite GLF, but there is evidence that the GLF of the quiescent population
in clusters is not universal. Furthermore, the GLF of quiescent galaxies is significantly steeper in clusters than in the
field. The overall GLF in clusters is consistent with that of field galaxies, except for the luminous tip, which is enhanced
in clusters versus the field.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
This paper deals with the observed variation in the flattening of galaxies with the density of galaxies in the subclusters
of Coma surrounding NGC 4889, NGC 4874, and NGC 4839 based on data from the Abastumani Combined Catalog of Galaxies. The mean
values of the observed ratios of the diameters of the galaxies, as well as histograms of their distributions, indicate that
in the central, dense regions of the subclusters within a volume of 0.5h
75
−1
Mpc3, E and S0 type galaxies are close to spheroidal. A significant reduction in the mean values of the diameters of the galaxies
in the subclusters is noted, regardless of their morphology relative to the galaxies in the halo of the Coma cluster. In the
subclusters, spiral galaxies are found with a hydrogen deficit that is more than 5 times the hydrogen deficit in spirals within
the halo of the cluster. According to their 3-D coordinates, most of the galaxies with a hydrogen deficit are located closer
to the south-east edge of the subcluster surrounding NGC 4874 near an extended gas filament in the x-ray region. This may
indicate that the subcluster is moving toward a central condensation of faint galaxies in the Coma cluster and a possible
merger with it.
__________
Translated from Astrofizika, Vol. 50, No. 3, pp. 355–368 (August 2007). 相似文献
9.
We analyze the properties of galaxy clusters in the region of the Leo supercluster using observational data from the SDSS
and 2MASS catalogs. We have selected 14 galaxy clusters with a total dynamical mass of 1.77 × 1015
M
⊙ in the supercluster region 130 by 60 Mpc in the plane of the sky (z ≃ 0.037). The composite luminosity function of the supercluster is described by a Schechter function with parameters that,
within the error limits, correspond to field galaxies and does not differ from the luminosity function of the richer Ursa
Major (UMa) supercluster for the same luminosity range (the bright end). The luminosity functions of early-type and late-type
galaxies in Leo at the faint end are characterized by a sharp decrease (α = −0.60±0.08) and a steep increase (α = −1.44± 0.10) in the number of galaxies, respectively. In the virialized cluster regions, the fraction of early-type galaxies
selected by the u-r color, bulge contribution, and concentration index among the galaxies brighter than M
K
* + 1 is, on average, 62%. This fraction is smaller than that in the UMa supercluster at a 2–3σ level. The near-infrared luminosities of galaxy clusters down to a fixed absolute magnitude correlate with their masses almost
in the same way as for other samples of galaxy clusters (L
200,K
∝ M
2000.63±0.11)). 相似文献
10.
The results of a statistical investigation of bright galaxies with a UV excess are given. The data obtained for them are compared
with those for normal galaxies. A list of bright galaxies (mpg ≤14m.5 ) with a UV excess has been compiled, numbering 461. Their absolute stellar magnitudes and average geometrical linear diameters
were determined. The relationships between Mpg and log D are given for galaxies with a UV excess and normal galaxies. The graphs of the relationships are expressed by second-degree
equations. It is shown that the UV evolutionary stage of the galaxies has no influence on the relationship between Mpg and log D.
Translated from Astrofizika, Vol. 43, No. 1, pp. 21-32, January–March, 2000. 相似文献
11.
We present the results of our observational study of two candidates for polar-ring galaxies (PRGs). Both objects, A2330-3751
and SDSS J000911.57-003654.7, are giant edge-on galaxies with large-scale structures resembling polar rings observed along
their minor axes. The optical diameter of the putative ring reaches 60 kpc in A2330-3751 and 18 kpc in SDSS J000911.57-003654.7.
To estimate the space density of PRGs, we have constructed their luminosity function in the range of B-band absolute magnitudes from −17·
m
5 to −21·
m
5. We have found that ∼10−3 of the nearby galaxies exhibit polar structures. Polar rings around early-type (E/S0) galaxies are encountered approximately
a factor of 3 more frequently than those around spiral ones. According to our estimates, ∼20–30 PRGs in which large-scale
rings are seen almost face-on must be observed among relatively bright galaxies (B ≤ 15
m
). 相似文献
12.
We present the results of our analysis of the frequencies of galaxies with tidal tails and M51-type galaxies in several deep
fields of the Hubble Space Telescope (HDF-N, HDF-S, HUDF, GOODS, GEMS). In total, we have found about seven hundred interacting
galaxies at redshifts z ≤ 1.5 in these fields. At z ≤ 0.7, the observed space densities of galaxies with tidal structures and M51-type galaxies have been found to increase as
∝(1 + z)
m
, where m ≈ 2.6. According to our estimates, over the last 6–7 Gyr, i.e., at z ≤ 0.7, about a third of the galaxies with M(B) ≤ −18
m
must have undergone strong gravitational perturbations and mergers and ∼1/10−1/5 of the galaxies have swallowed relatively
low-mass nearby satellites typical of M51-type galaxies. The possible decrease in the time scale on which a distant galaxy
appears peculiar with growing z can increase considerably the estimated rate of mergers. 相似文献
13.
We determine the mass profile of a synthetic cluster built from the combination of 59 nearby clusters observed in the ESO
Nearby Abell Cluster Survey (ENACS). We use ellipticals and S0s as tracers of the cluster potential, and solve the Jeans equation
assuming isotropic orbits. Such an assumption is justified by the analysis of the shape of the velocity distribution of ellipticals
and S0s. We find that the cluster mass profile is consistent with the Navarro, Frenk and White(NFW) model. We use this cluster
mass profile to search for equilibrium solutions for the other cluster galaxy populations: very bright ellipticals (M
R
≤–22+5 log h),early-type spirals (Sa-Sb), and late-type spirals and irregulars (Sbc-Ir), together with emission-line galaxies. We find
equilibrium solutions for both the early- and the late-spirals, but not for the very bright ellipticals. The dynamics of very
bright ellipticals is probably affected by dissipative processes which invalidate the use of the collisionless Jeans equation.
The equilibrium solution found for the early-spirals implies them to move on nearly-isotropic orbits. Late-spirals are instead
found to be on mildly radial orbits, with the radial anisotropy increasing outwards. We discuss the implications of these
results for the evolutionary histories of the different populations of cluster galaxies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
14.
P. Amram C. Mendes de Oliveira H. Plana C. Balkowski M. Bolte 《Astrophysics and Space Science》2002,281(1-2):397-400
We present kinematics and photometric evidence for the presence of seven candidate tidal dwarf galaxies in Stephan's Quintet.
The central regions of the two most probable parent galaxies, NGC 7319 and NGC 7318B, contain little or no gas whereas the
intragroup medium and, in particular, the optical tails that seem to be associated with NGC 7318B are rich in cold and ionized
gas. Two tidal dwarf candidates may be located at the edge of a tidal tail, another located within a tail, and for the four
others there is no obvious stellar/gaseous bridge between them and the parent galaxy. Two of the candidates are associated
with H I clouds, one of which is, in addition, associated with a CO cloud. All seven regions have low continuum fluxes and
high Hα luminosity densities [F(Hα) = (1-60) × 10-14 ergs s-1 cm-2]. Their magnitudes (MB = –16.1 to –12.6), sizes (∼ 3.5 h75
-1 kpc), colors (typically B – R = 0.7), and gas velocity gradients (∼ 8 –26 h75 km s-1 kpc-1) are typical for tidal dwarf galaxies. In addition, the ratios between their star formation rates determined from Hα and
from the B-band luminosity are typical of other tidal dwarf galaxies. The masses of the tidal dwarf galaxies in Stephan's
Quintet range from ∼ 2 × 108 to 1010 M⊙, and the median value for their inferred mass-to-light ratios is 7 (M/L)⊙. At least two of the systems may survive possible ‘fallbacks’ or disruption by the parent galaxies and may already be, or
turn into, self-gravitating dwarf galaxies, new members of the group.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
15.
The relationship between the rotation curves for the galaxies and the distribution of mass and angular momentum within the
galaxies is examined. The theory of angular momentum transfer is applied to the observed properties of the galaxies. The coupling
between the dynamical mass of a spiral galaxy and its luminosity is studied. Most of the spiral galaxies in subclusters surrounding
NGC 4889, NGC 4874, and NGC 4839 in the Coma cluster are galaxies that have lower luminosities, with MB fainter than −21m.5. These galaxies are characterized by a higher mass-to-luminosity ratio than that of the galaxies with higher luminosities
MB brighter than −21m.5, which suggests the presence of a large fraction of dark matter in the spiral galaxies of the subclusters.
Translated from Astrofizika, Vol. 52, No. 1, pp. 75–84 (February 2009). 相似文献
16.
We present results of an investigation of clustering evolution of field galaxies between a redshift of z ∼ 1 and the present epoch. The current analysis relies on a sample of ∼ 14000 galaxies in two fields of the COMBO 17 survey.
The redshift distribution extends to z ∼ 1. The amplitude of the three-dimensional correlation function can be estimated by means of the projected correlation function
w(r
p
). The validity of the deprojection was tested on the Las Campanas Redshift Survey (LCRS). In a flat cosmology with non-zero
cosmological constant for bright galaxies (M
B ≤-18) the clustering growth is proportional to (1+z)
-2. However, the measured clustering evolution clearly depends on Hubble type. While locally the clustering strength of early
type galaxies is equal to that of the bright galaxies, at high redshifts they are much stronger clustered, and thus the clustering
has to evolve much more slowly.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
High sensitivity observations of radio halos in galaxy clusters at frequencies ν ≤ 330 MHz are still relatively rare, and very little is known compared to the classical 1.4 GHz images. The few radio halos
imaged down to 150–240 MHz show a considerable spread in size, morphology and spectral properties. All clusters belonging
to the GMRT Radio Halo Survey with detected or candidate cluster-scale diffuse emission have been imaged at 325 MHz with the
GMRT. Few of them were also observed with the GMRT at 240 MHz and 150 MHz. For A 1682, imaging is particularly challenging
due to the presence of strong and extended radio galaxies at the center. Our data analysis suggests that thew radio galaxies
are superposed to very low surface brightness radio emission extended on the cluster scale, which we present here. 相似文献
18.
The distance modulus of the Virgo cluster has been reexamined based on the Tully-Fisher relation between fully corrected B.
1
0
values and 21 cm velocity width derived from RC3 catalogue for spiral galaxies of Sbc-Sdm types, belonging to the “low-velocity”
Virgo subcluster, singled out according to the statistical method proposed by Anosova, and led to the value μ = 31.15 ± 0.57
mag. A strong dependence of the intrinsic scatter in the Tully-Fisher relation on the apparent axes ratio of galaxies has
been found, with a value of 0.4 mag for strongly flattened, highly inclined galaxies and galaxies with small inclinations
and a value of 0.72 mag for objects with intermediate values of axes ratio. The restriction to samples only with galaxies
with photoelectric observations does not lead to a considerable change of amplitude of scatter and decreases the value the
of distance modulus.
Published in Astrofizika, Vol. 42, No. 1, pp. 37–46, January–March, 1999. 相似文献
19.
A fourth list of optically identified point sources from the IRAS Point Source Catalog, containing 34 nonstellar objects,
is given. The identifications were made on the basis of the Digitized Sky Survey (DSS), the First Byurakan Survey, blue and
red maps from the Palomar Sky Survey (FBS), and infrared fluxes at 12, 25, 60, and 100 μm in the region of +61° ≤ δ ≤ 65°
and 11h15m ≤ α ≤ 18h35m with an area of 200 sq. deg. For the identified objects we determined their optical coordinates, their departures from the
IR coordinates, their stellar V magnitudes, color indices CI, and preliminary types. The optical magnitudes of the objects
are in the range 12m.5-27m. The identified galaxies include Seyfert candidates, interacting pairs, galaxies with companions, superassociations, etc.
The galaxies are encountered in groups in many cases, and the IR emission may be due to heating of intergalactic matter within
a group. Finder charts from the DDS are given for these objects.
Translated from Astrofizika, Vol. 41, No. 3, pp. 359–366, July–September, 1998. 相似文献
20.
A. M. Mickaelian 《Astrophysics》2000,43(3):309-321
A fifth list of objects from the BIG (Byurakan-IRAS galaxies) sample is given: 89 galaxies identified with 59 point sources
from the IRAS Point Source Catalog. The identifications were based on the Digital Sky Survey (DSS), the First Byurakan Survey,
blue and red maps from the Palomar Observatory Sky Survey, and infrared fluxes at 12, 25, 60, and 100 mm in the region of+65°
≤ δ ≤69δ and 5h10m ≤ α ≤9h 15m with an area of 96 deg2. For the identified galaxies the optical coordinates, their departures from the IR coordinates, and the stellar V magnitudes,
morphological types, angular sizes, and position angles were determined. The objects have optical magnitudes in the range
of 14m. 1-21m.5 and angular sizes in the range of 2″-47″. The galaxies are mainly spiral in morphology. Compact galaxies and Seyfert candidates,
interacting pairs, “mergers,” galaxies with companions and superassociations, groups of galaxies (including compact ones),
and others are encountered, which shows the importance of these objects for the study of the relationships among the phenomena
of star formation, activity, and interactions. Finder charts from the DSS are given for these objects. New designations and
numbering are introduced for galaxies in the studied sample.
Translated from Astrofizika, Vol. 43, No. 3, pp. 425-441, July– September, 2000.
The NASA/IPAC Extragalactic Database (NED), operated by the Jet Propulsion Laboratory, California Institute of Technology,
under contract with NASA. 相似文献