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1.
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 6m.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.  相似文献   

2.
A third list of point sources from the IRAS Point Source Catalog (PSC), optically identified with late-type stars, is given. The list contains data on 34 objects. The identification was based on the Digitized Sky Survey (DSS), the First Byurakan Survey (FBS). blue and red maps of the Palomar Observatory Sky Survey, and infrared fluxes at wavelengths of 12, 25, 60, and 100 mm in the regions of +61° ≤ δ ≤ +65°, 06h45m ≤ α ≤ 17h28m and +69° ≤ δ ≤ +73°, 03h50m ≤ α ≤ 18h10m. Of 34 objects given in the IRAS PSC as unidentified sources of infrared radiation, 11 are associated with known stars in existing catalogs, 6 are objects from the FBS survey of late-type stars, and 17 sources remained unknown in the optical range, 3 of them also being sources in the IRAS Serendipitous Survey Catalog (SSC). The optical coordinates, their departures from the 1R coordinates, the V magnitudes, the color indices CI, and the preliminary spectral subtypes were determined. The objects have optical magnitudes in the range of 7h.6-13m.6. Finder charts from the DSS are given for 23 objects. Translated from Astrofizika, Vol. 43, No. 1, pp. 77-84, January–March, 2000.  相似文献   

3.
The low-dispersion spectra of the First Byurakan Survey and the red and blue images of the Palomar Observatory Sky Survey have been used to identify optically 100 infrared sources from the IRAS Point Source Catalog. The work was carried out over the region 3h 50m ≤ α ≤ 7h 40m and +69° ≤ δ −73° with an area of 75 square degrees. The optical coordinates, their deviations from the infrared coordinates, V magnitudes, color indices, preliminary classes for all the objects, and a number of remarks on interesting objects are presented. Three objects were found to be quasars, 36 are galaxies (including Seyferts and an interacting pair), 5 are faint planetary nebulae, 9 are carbon stars, and 47 are stars of late M subclasses. Translated fromAstrofizika, Vol. 40, No. 1, pp. 5–18, February, 1997.  相似文献   

4.
A fourth list of point sources from the IRAS Point Source Catalog (PSC) that are optically identified with stars of late spectral types is given. The list contains data on 41 objects. The identifications were based on the Digital Sky Survey (DSS), the First Byurakan Survey, blue and red maps of the Palomar Observatory Sky Survey, and infrared fluxes at the wavelengths 12, 25, 60, and 100 μm in the region of +65° ≤ δ ≤ +69° and 05h10m ≤ α ≤ 18h10m. Of the 41 objects, which are given in the IRAS PSC as unidentified sources of infrared emission, 9 are associated with known stars in existing catalogs while 32 sources remained unidentified in the optical range, one of which is also a source in the deep IRAS survey (IRAS Serendipitous Source Catalog). The optical coordinates, their departures from the IR coordinates, the V stellar magnitudes, the color indices CI, and the preliminary spectral subtypes have been determined. The objects have optical magnitudes in the range of 8m.5-14m.5. Finder charts from the DSS are given for 32 of the objects. Translated from Astrofizika, Vol. 43, No. 3, pp. 361-368, July–September, 2000.  相似文献   

5.
Radio stars are identified optically with bright stars located in the direction of the cluster A3487 (RA(J) = 11h31m58s, DEC(J) = −31°11’34".8) with an accuracy determined by the refraction of radio waves in the interstellar medium in this direction of the sky. Within an area of 1 sq. degree, 60% of the strong radio sources with P > 0.004 Jy are identified with stars brighter than 10 m.  相似文献   

6.
Part three of optically identified point sources from the IRAS Point Source Catalog contains 113 objects. The identifications were based on the Digitized Sky Survey (DSS), the First Byurakan Survey, blue and red maps from the Palomar Sky Survey, 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. Of the 119 sources in this region, 6 could not be identified owing to the absence of optical counterparts with the given coordinates. For the identified objects we determined their optical coordinates, their departures from the IR coordinates, and their stellar V magnitudes, color indices (CI), and preliminary types. The objects have optical magnitudes in the range of 8n–21m. Of the 113 objects, 31 turned out to be stars of spectral types K and M, 1 is a planetary nebula, 2 are candidates to be quasi- stellar objects, and 79 are galaxies. A list of the 48 nonstellar objects is given. The identified galaxies include Seyfert candidates, interacting pairs, galaxies with companions, superassociations, etc. The galaxies are in groups in many cases, and the IR emission may be due to heating of intergalactic matter within a group. Finder charts for these objects from the DSS are given. Translated from Astrofizika, Vol. 41, No. 2, pp. 251–262, April-June, 1998.  相似文献   

7.
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.  相似文献   

8.
Part five of optically identified point sources from the IRAS Point Source Catalog (PSC) contains data on 19 late-type stars. The identifications were based on the Digitized Sky Survey (DSS), the First Byurakan Survey (FBS), blue and red maps of the Palomar survey (POSS), and infrared fluxes at 12, 25, 60, and 100 mm in the region of +61° ≤ δ ≤ +65° and 05 h 30 m ≤ α ≤ 18 h 35 m with an area of 357 sq. deg. Of the 76 objects given in the IRAS PSC as unidentified sources of infrared radiation, 51 are associated with known stars in existing catalogs, 6 are objects from the FBS of late-type stars, and 19 sources remained unknown in the optical range. For the identified stars we determined the optical coordinates, their departures from the IR coordinates, the Vstellar magnitudes, the color indices CI,and the preliminary spectral subtypes. The objects have optical magnitudes in the range of 8 m −16 m .Gas-dust shells are assumed to exist around four of the sources. Finder charts from the DSS are given for 19 of the objects. Translated from Astrofizika, Vol. 42, No. 1, pp. 53–59, January–March, 1999.  相似文献   

9.
The second portion of optically identified point sources from the IRAS Point Source Catalog contains 104 objects. The identifications were made on the basis of the Digitized Sky Survey (DSS), the First Byurakan Survey (FBS), blue and red maps of the Palomar Survey (POSS), and infrared fluxes at wavelengths of 12, 25, 60, and 100 fim in the region of +61 ° ≤ δ ≤ +65°and 50h30m ≤ α ≤ 11h15m with an area of 157 sq. deg. Of the 114 sources in this region, 10 could not be identified because of the absence of the corresponding optical counterparts with the given coordinates. For the identified objects we determined their optical coordinates, their departure from the IR coordinates, the stellar V magnitudes, the color indices CI, and the preliminary types. The objects have optical magnitudes in the range of 8n–21m. Of the 104 objects, 46 turned out to be stars of spectral types K and M, 1 is a planetary nebula, 3 are QSO candidates, and 54 are galaxies. In the present work we give a list of the 58 nonstellar objects. The identified galaxies include Seyfert candidates, interacting pairs, galaxies with companions and superassociations, etc. Finder charts for these objects from the DSS are given. Translated from Astrofizika, Vol. 40, No. 4, pp. 581–593, October-December, 1997.  相似文献   

10.
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.  相似文献   

11.
43 stellar objects with Hα emission are discovered by slitless spectroscopy in a 14’ × 14' area near the nebula GM 2-41 located in the HII region DR 15 at the southern edge of the Cyg OB2 association. Emission is detected for the first time for 30 of these objects. Based on VI and JHK photometric data, the overwhelming majority of these objects are classified as young stellar objects in spectral classes F7-M3 with ages of ~1 Myr. The stars are distributed nonuniformly and form two groups which have the same coordinates as the UCHII regions G0.79 + 0.3 and G79.2 + 0.4.  相似文献   

12.
Spectral and photographic observations of an 11′×11′ region in the center of the known association Cyg OB7 are presented. The observations were made on the 2.6-m telescope of the Byurakan Astrophysical Observatory in 2004. The spectral camera SCORPIO, a multiregime focal reducer for the primary focus, was used. One new HH node and three new emission stars were discovered in the region under study. One of the previously known emission stars is found to have spectral class M0Ve and to lie at a distance of 200 pc. Some variability is detected in the brightness of a known infrared nebula and the cometary nebula CN2. __________ Translated from Astrofizika, Vol. 49, No. 3, pp.375–390 (August 2006).  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
The PLAnetary Transits and Oscillations of stars Mission (PLATO), presented to ESA in the framework of its “Cosmic Vision” programme, will detect and characterize exoplanets by means of their transit signature in front of a very large sample of bright stars, and measure the seismic oscillations of the parent stars orbited by these planets in order to understand the properties of the exoplanetary systems. PLATO is the next-generation planet finder, building on the accomplishments of CoRoT and Kepler: i) it will observe significantly more stars, ii) its targets will be 2 to 3 magnitudes brighter (hence the precision of the measurements will be correspondingly greater as will be those of post-detection investigations, e.g. spectroscopy, asteroseismology, and eventually imaging), iii) it will be capable of observing significantly smaller exoplanets. The space-based observations will be complemented by ground- and space-based follow-up observations. These goals will be achieved by a long-term (4 years), high-precision, high-time-resolution, high-duty-cycle monitoring in visible photometry of a sample of more than 100,000 relatively bright (m V  ≤ 12) stars and another 400,000 down to m V  = 14. Two different mission concepts are proposed for PLATO: i) a “staring” concept with 100 small, very wide-field telescopes, assembled on a single platform and all looking at the same 26° diameter field, and ii) a “spinning” concept with three moderate-size telescopes covering more than 1400 degree2. See for The PLATO Consortium.  相似文献   

16.
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).  相似文献   

17.
We present a variety of well behaved classes of Charge Analogues of Tolman’s iv (1939). These solutions describe charged fluid balls with positively finite central pressure, positively finite central density; their ratio is less than one and causality condition is obeyed at the centre. The outmarch of pressure, density, pressure-density ratio and the adiabatic speed of sound is monotonically decreasing, however, the electric intensity is monotonically increasing in nature. These solutions give us wide range of parameter for every positive value of n for which the solution is well behaved hence, suitable for modeling of super dense stars. keeping in view of well behaved nature of these solutions, one new class of solutions is being studied extensively. Moreover, this class of solutions gives us wide range of constant K (0.3≤K≤0.91) for which the solution is well behaved hence, suitable for modeling of super dense stars like Strange Quark stars, Neutron stars and Pulsars. For this class of solutions the mass of a star is maximized with all degree of suitability, compatible with Quark stars, Neutron stars and Pulsars. By assuming the surface density ρ b =2×1014 g/cm3 (like, Brecher and Caporaso in Nature 259:377, 1976), corresponding to K=0.30 with X=0.39, the resulting well behaved model has the mass M=2.12M Θ, radius r b ≈15.27 km and moment of inertia I=4.482×1045 g cm2; for K=0.4 with X=0.31, the resulting well behaved model has the mass M=1.80M Θ, radius r b ≈14.65 km and moment of inertia I=3.454×1045 g cm2; and corresponding to K=0.91 with X=0.135, the resulting well behaved model has the mass M=0.83M Θ, radius r b ≈11.84 km and moment of inertia I=0.991×1045 g cm2. For n=0 we rediscovered Pant et al. (in Astrophys. Space Sci. 333:161, 2011b) well behaved solution. These values of masses and moment of inertia are found to be consistent with other models of Neutron stars and Pulsars available in the literature and are applicable for the Crab and the Vela Pulsars.  相似文献   

18.
The properties of powerful (flux >10−19 W m−2 Hz−1) type III bursts observed in July – August 2002 by the radio telescope UTR-2 at frequencies 10 – 30 MHz are analyzed. Most bursts have been registered when the active regions associated to these bursts were located near the central meridian or at 40° – 60° to the East or West from it. All powerful type III bursts drift from high to low frequencies with frequency drift rates 1 – 2.5 MHz s−1. It is important to emphasize that according to our observations the drift rate is linearly increasing with frequency. The duration of the bursts changes mainly from 6 s at frequency 30 MHz up to 12 s at 10 MHz. The instantaneous frequency bandwidth does not depend on the day of observations, i.e. on the disk location of the source active region, and is increasing with frequency.  相似文献   

19.
An experiment was conducted in conjunction with the total solar eclipse on 29 March 2006 in Libya to measure both the electron temperature and its flow speed simultaneously at multiple locations in the low solar corona by measuring the visible K-coronal spectrum. Coronal model spectra incorporating the effects of electron temperature and its flow speed were matched with the measured K-coronal spectra to interpret the observations. Results show electron temperatures of (1.10±0.05) MK, (0.70±0.08) MK, and (0.98±0.12) MK, at 1.1 R ⊙ from Sun center in the solar north, east and west, respectively, and (0.93±0.12) MK, at 1.2 R ⊙ from Sun center in the solar west. The corresponding outflow speeds obtained from the spectral fit are (103±92) km s−1, (0+10) km s−1, (0+10) km s−1, and (0+10) km s−1. Since the observations were taken only at 1.1 R ⊙ and 1.2 R ⊙ from Sun center, these speeds, consistent with zero outflow, are in agreement with expectations and provide additional confirmation that the spectral fitting method is working. The electron temperature at 1.1 R ⊙ from Sun center is larger at the north (polar region) than the east and west (equatorial region).  相似文献   

20.
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.  相似文献   

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