A peculiar distribution of radial velocities of faint radio-galaxies with 13.0≤m corr≤15.5

A sample of 41 radio-galaxies with 13.0m _corr15.5 has been analyzed to test the angular redshift anisotropy discovered on Sc I galaxies by Rubin, Rubin and Ford. The sample does not present their anisotropy but contains an even more curious distribution of radial velocities which suggests that the Rubin-Ford effect results from an anomalous redshift of light when it travels through clusters of galaxies.     

First Byurakan Spectral Sky Survey. Late-type stars. VIII. Zone + 80 ≤ δ ≤ + 90°

The eighth list of late-type stars of spectral classes M and C detected on the plates of the First Byurakan Spectral Sky Survey (FBS) in the zone +80 +90° is presented. Of the 79 objects detected, 67 are new discoveries (66 M stars and one carbon star); 16 objects are unidentified IRAS sources. The equatorial coordinates, spectral classes, and magnitudes are given.Translated fromAstrofizika, Vol. 39, No. 4, pp. 523–529, November, 1996.     

First Byurakan Spectral Sky Survey. Blue stellar objects. XI. Region +80 ≤ δ ≤ +90°

The eleventh list of blue stellar objects in the second part of the First Byurakan Spectral Sky Survey (FBS) is presented. The list consists of 64 objects located in the region +80 +90° and 2^h 08^m a 20^h 15^m. The objects haveV magnitudes in the range 12.3–17.4 andB–V color indices in the range -0.55-+0.55. Of the 98 objects, 56 are newly discovered. Tentative classifications are given for 28 objects, of which there is one planetary nebula, 6 possible quasars, 15 possible white dwarfs, and 6 possible cataclysmic variables. Two of the latter are possibly novae having erupted at the epoch of exposure of the FBS plates in this region.Translated fromAstrofizika, Vol. 39, No. 4, pp. 531–540, November, 1996.     

Properties of BL Lac Objects with Redshift≤0.2

1 INTRODUCTIONBlazars, including BL Lacertae objects and Optical Violently Variable (OVV) quasars,belong to a class of active ga1actic nuclei (AGNs), the spectrum of which is dominated bynontherma1 radiation from re1ativistic electrons in jets pointing at us (e.g. BlandfOrd & Rees1978; Urry & Padovani 1995). The entire electromagnetic spectraI energy distributions (SEDs)usually reveal two broad components, the low energy part, peaking in the IR to soft X-rayrange, and the high en…     

First Byurakan Spectral Sky Survey. Stars of late spectral types. −11° ≤ δ ≤ −7° belt

A 10th list of late-type M and C stars found on plates of the First Byurakan Spectral Sky Survey in the − 11° ≤ δ ≤ − 7° belt with an area of about 1070 deg² is given. The list contains data on 169 red stars, 117 of which were found for the first time: 8 are new C stars, 3 are Cstar candidates, 104 are M stars, 1 is either an M or an S star, and 1 object on the survey plate cannot be classified. Of the 117 objects, 47 are unidentified IRAS sources. A statistical analysis of the objects that are and are not identified with IRAS sources shows that the identified stars are, with a high probability, brighter and have relatively more massive envelopes. Two stars were found to have fairly large brightness variability (with an amplitude of at least 6^m.O). Gasdust shells are assumed to exist around nine of the IRAS sources. The equatorial coordinates, spectral types, and stellar magnitudes, determined on Palomar E maps, are given for the selected objects. Translated from Astrofizika, Vol. 41. No. 4, pp. 545–559, October–December, 1998.     

First Byurakan Spectral Sky Survey. Blue Stellar Objects. XII. The Region -3° ≤ δ ≤ +1°

The twelfth list of blue stellar objects in the second part of the First Byurakan Spectral Sky Survey (FBS) is presented. This list contains 143 objects in the region -3° +1° at high latitudes with an area of approximately 992 square degrees (62 fields). The objects have magnitudes V of 11.8-18.1 and B-V colors ranging from -0.82 to +0.81. Of the 143 objects, 51 have been discovered for the first time. Equatorial coordinates, V magnitudes, color indices, and preliminary classifications of the objects are given. DSS identification charts are given for the newly discovered objects.     

First Byurakan Spectral Sky Survey. Stars of Late-Spectral Types. XIII. Zone +1° ≤ δ ≤ +13°

The thirteenth list of faint late M and carbon type stars detected on the plates of the First Byurakan Spectral Sky Survey in zone +1° +13° covering about 3118 sq. degrees is presented. From 285 stars, 161 are newly detected objects: they are 17 carbon stars, 25 carbon star candidates, and 117 M-type stars. The spectral type of two objects is assumed to be between M8 - M9 or late N-subtypes. Among 161 objects, 85 (66 PSC + 19 FSC) are unclassified IRAS sources. Accurate positions, spectral classes, red magnitudes, and color indices are given using several astronomical databases. Finding charts from DSS are given for the most interesting objects.     

First Byurakan Spectral Sky Survey. Stars of Late-Spectral Types. XIV. Zone +13° ≤ δ ≤ +33°

We present the fourteenth list of faint late M and carbon type stars detected on the plates of the First Byurakan Spectral Sky Survey in the zone +13° +33° covering about 4736 sq. degrees. From 260 stars, 118 are newly detected objects: they are 19 carbon stars, 5 carbon star candidates, and 94 M-type stars. Among 118 detected objects 73( 57 PSC + 16 FSC ) are unclassified IRAS sources. Accurate positions, spectral classes, red magnitudes, color indices, and near-infrared J, H and K photometry are given, using several astronomical databases. Finding charts from DSS are given for the most interesting objects.     

First Byurakan Spectral Sky Survey. Stars of Late Spectral Types. XII. Zone -3° ≤ δ ≤ +1°

The twelfth list of faint late M and carbon type stars detected on the plates of the First Byurakan Spectral Survey in zone -3° +1° covering about 1070 sq. degrees is presented. From 86 detected stars, 57 are newly discovered objects: they are 3 R-type carbon stars, 2 carbon star candidates and 52 M-type stars. Among the latter 34 (28 PSC + 6 FSC) are unclassified IRAS sources. Equatorial coordinates, spectral classes, color indices, and red magnitudes determined from the Palomar E-charts are presented.     

First Byurakan Spectral Sky Survey. Stars of Late Spectral Types. XI. Zone -7° ≤ δ ≤ -3°

The eleventh list of faint late M and carbon type stars detected on the plates of the First Byurakan Spectral Survey in zone -7° -3° and covering about 1000 square degrees is presented. From 126 detected stars, 88 are newly discovered objects: they are 6 carbon stars, 8 carbon star candidates, and 74 M-type stars; among the latter 38 (26 PSC + 12 FSC) are unclassified IRAS sources, and one object is an unclassified ROSAT source. Distances to the 6 newly discovered early-type carbon stars are estimated. Equatorial coordinates, red magnitudes, and spectral classes determined from the Palomar E-charts are provided. The lack of optical counterparts on Palomar O and E maps for two detected late M-type stars indicates a large variability in brightnesses of these objects (amplitude not smaller than 7.0 magnitude).     

The first byurakan spectral sky survey. Late spectral class stars. VII. The zone +76° ≤ δ ≤ +80°

We present the seventh list of stars of the late M and C spectral classes taken from the plates of the First Byurakan Spectral Sky Survey (FBS). Data on 24 objects, 2 of which are carbon stars of early subclasses (R-stars), are given for the first time. The spectral membership of two known stars is established. The objects lie in the zone 3 ^h 40 ^m 18 ^h 30 ^m and +76° +80°.Translated fromAstrofizika, Vol. 38, No. 3, 1995.     

On numerical evaluation of theH-functions of transport problems by kernel approximation for the albedo 0<ω≤1

Das Gupta represented theH-functions of transport problems for the albedo [0, 1] in the formH(z)=R(z)–S(z) (see Das Gupta, 1977) whereR(z) is a rational function ofz andS(z) is regular on [–1, 0] ^c . In this paper we have representedS(z) through a Fredholm integral equation of the second kind with a symmetric real kernelL(y, z) as . The problem is then solved as an eigenvalue problem. The kernel is converted into a degenerate kernel through finite Taylor's expansion and the integral equation forS(z) takes the form: (which is solved by the usual procedure) where _r 's are the discrete eigenvalues andF _r 's the corresponding eigenfunctions of the real symmetric kernelL(y, z).     

Estimation of Stellar Atmospheric Parameters from LAMOST DR8 Low-resolution Spectra with 20 ≤ S/N < 30

The accuracy of the estimated stellar atmospheric parameter evidently decreases with the decreasing of spectral signal-to-noise ratio(S/N) and there are a huge amount of this kind observations, especially in case of S/N < 30.Therefore, it is helpful to improve the parameter estimation performance for these spectra and this work studied the(T_eff, log g, [Fe/H]) estimation problem for LAMOST DR8 low-resolution spectra with 20 ≤ S/N < 30. We proposed a data-driven method based on m...     

Properties of the Main Phases of the Super Geomagnetic Storms(ΔSYM-H ≤-250 nT) with Different Heliolongitudes

We studied the properties of the main phases of 24 super geomagnetic storms(SGSs)(ΔSYM-H ≤-250 nT)since 1981. We divided the SGSs into two subgroups: SGSs-Ⅰ(-400 nT <Δ SYM-H ≤-250 nT) and SGSs-Ⅱ(ΔSYM-H ≤-400 nT). Of the 24 SGSs, 16 are SGSs-Ⅰ and eight are SGSs-Ⅱ. The source locations of SGSs were distributed in the longitudinal scope of [E37, W66]. 95.8% of the SGSs were distributed in the longitudinal scope of [E37, W20]. East and west hemispheres of the Sun had 14 and 10 SGSs, respectively...     

First Byurakan Spectral Sky Survey. Blue stellar objects. VII. Zone +61° ≤δ ≤, +65°

The seventh list of blue stellar objects in the second part of the First Byurakan Spectral Sky Survey (FBS) is presented. The objects are located in the zone + 61° + 65° and 5 ^h 30^m 18 ^h 40 ^m .The list contains data on 119 blue stellar objects detected, of which 73 are previously unknown. A preliminary classification of the objects is given. The limiting magnitude of the FBS plates are determined using the photometric calibration of the charts of the Palomar Sky Survey.Translated fromAstrofizika, Vol. 37, No. 1, pp. 43–55, January–March, 1994.     

First Byurakan Spectral Sky Survey. Blue stellar objects. VIII. zone +65° ≤ δ ≤, + 69°

The eighth list of blue stellar objects in the second part of the First Byurakan Spectral Sky Survey (FBS) is presented. The objects are located in the zone +65° +69° and 5 ^h 15^m 18 ^h 05^m.The list contains data on 98 blue stellar objects detected, of which 73 are previously unknown. A preliminary classification of the objects is given. The exact coordinates of the centers and the limiting magnitudes of the plates for this zone have been determined using the charts of the Palomar Sky Survey.Translated from Astrofizika, Vol. 37, No. 2, pp. 197–206, April–June, 1994.This work has been performed with financial support of the ESO C&EE fund (A-02-043).     

Exact solution of the equation of radiative transfer for semi-infinite plane-parallel isotropic scattering atmosphere with scattering albedo ω0 ≤ 1 by a method based on Laplace transform and Wiener-Hopf technique

By performing the one-sided Laplace transform on the scalar integro-differential equation for a semi-infinite plane-parallel isotropic scattering atmosphere with a scattering albedo ₀ 1, an integral equation for the emergent intensity has been derived. Application of the Wiener-Hopf technique to this integral equation will give the emergent intensity. The intensity at any optical depth for a positive scattering angle is also derived by inversion. The intensity at any optical depth for a negative scattering angle is also derived in terms of Cauchy's principal value using Plemelj's formulae.     

Clustering of galaxies on scales of ≤10<Emphasis Type="Italic">h</Emphasis><Superscript>−1</Superscript> based on the coma,bridge, and A1367 clusters

A correlation analysis is made of the spatial distribution of galaxies in the Coma, Bridge, and A1367 clusters, which form the Coma supercluster. The scale of the clustering of galaxies and the variation in their density distribution with the main parameters of the galaxies– luminosity, morphological type, and observed H I deficiency in the 21 cm line– are evaluated. The mass-to-luminosity ratios are computed for the spiral galaxies in the Coma, Bridge, and A1367 clusters. It is suggested that a larger fraction of hypothetical dark matter may be concentrated in the spiral galaxies which predominantly populate the subclusters previously identified by us within these clusters than in the spiral galaxies observed in the peripheral regions of the clusters.     

00~h00~m+00°00′天区的类星体物端稜镜光谱巡天——(Ⅱ)00~h00~m≤赤经<00~h13~m赤纬<+00°00′

本文给出UK Schmidt 823天区,00~h00~m≤赤经<00~h13~m,赤纬<+00°00′的四分之一区域内Q≥4的类星体候选者121个的坐标,B_j~*星等及证认图,对其中Q≥5的天体进行了谱线证认,给出它们的红移值。