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1.
Five sky areas about the radio sources ICRS 1254+571, ICRS 1345+125, ICRS 1641+399, ICRS 1732+389, and ICRS 1807+698 were observed with the aim to identify reliably the extragalactic radio sources in these areas with bright infrared objects and objects in the optical range. The test CCD observations were made in the U, V, and R bands of the Johnson system with the 2-meter telescope of the Terskol Peak Observatory (North Caucasus, Russian Federation). The U, V, and B magnitudes and the equatorial coordinates α and δ in the USNO-A2.0 catalog system were determined for objects down to V ≈ 23m in 8.5′ × 8.5′ areas, and these objects were identified with stars and infrared objects in the 2MASS catalog. The CCD image processing realized within the MIDAS/ROMAFOT program package on the basis of a new method for flat-field elimination is briefly described.  相似文献   

2.
We describe the modifications made in the design of the Kyiv meridian axial circle (MAC) and in the observation technique after the instrument was equipped with a CCD camera with an array of 1040×1160 pixels. The observations are performed in the drift-scan mode (time-delay imaging) with an effective exposure time of 108 s for equatorial stars. The MAC photometric system reproduces the standard V system; the limiting magnitude is V = 17 m . The observations made with the modified MAC in 2001–2003 served as the basis for the KMAC1 catalog which contains positions, proper motions, and magnitudes B, V, R, r′, J for 100 000 stars in the sky areas with the ICRF objects. The errors of positions and V magnitudes in the catalog are 50–90 mas and 0.1 m , respectively, for stars with V = 15 m . Stars in the equatorial sky areas and radio stars are presently observed with the aim to determine their exact positions, proper motions, and magnitudes. The catalogs are available in the data base of the Centre de Données Astronomiques de Strasbourg (ftp.cdsarc.u-strasbg.fr) and on the site of the Main Astronomical Observatory (http://www.mao.kiev.ua).  相似文献   

3.
We consider a sample of 412 galaxies with radial velocities V LG < 2500 kms?1 situated in the sky region of RA = 13. m 0–19. m 0, Dec = +10?...+40? between the Local Void and the Supergalactic plane. One hundred and eighty-one of them have individual distance estimates. Peculiar velocities of the galaxies as a function of Supergalactic latitude SGB show signs of Virgocentric infall at SGB < 10? and motion from the Local Void at SGB > 60?. A half of the Hercules–Bootes galaxies belong to 17 groups and 29 pairs, with the richest group around NGC5353. A typical group is characterized by the velocity dispersion of 67 km s?1, the harmonic radius of 182 kpc, the stellar mass of 4.3 × 1010 M ⊙ and the virialto- stellar mass ratio of 32. The binary galaxies have the mean radial velocity difference of 37 kms?1, the projected separation of 96 kpc, the mean integral stellar mass of 2.6×109M ⊙ and the mean virial-to-stellar mass ratio of about 8. The total dark-matter-to-stellar mass ratio in the considered sky region amounts to 37 being almost the same as that in the Local Volume.  相似文献   

4.
In 2013–2015 the Laboratory of spectroscopy and photometry of extragalactic objects (LS-PEO) of the Special Astrophysical Observatory together with Armenian specialists upgraded the 1-m Schmidt telescope of the Byurakan Astrophysical Observatory of the National Academy of Sciences of Armenia. We completely redesigned the control system of the telescope: we replaced the actuating mechanisms, developed telescope control software, and made the guiding system. We reworked and prepared a 4k × 4k Apogee (USA) liquid-cooled CCD with RON ~ 11.1 e?, a pixel size of 0.″868, and field of view of about 1□°, and in October 2015 mounted it in the focus of the telescope. The detector is equipped with a turret bearing 20 intermediate-band filters (FWHM = 250 Å) uniformly covering the 4000–9000 Å wavelength range, five broadband filters (u, g, r, i, z SDSS), and three narrow-band filters (5000 Å, 6560 Å and 6760 Å, FWHM = 100 Å). During the first year of test operation of the 1-m telescope we performed pilot observations within the framework of three programs: search for young stellar objects, AGNevolution, and stellar composition of galaxy disks.We confirmed the possibility of efficiently selecting of young objects using observations performed in narrow-band Hα and [SII] filters and the intermediate-band 7500 Å filter. Three-hours long exposures with SDSS g-, r-, and i-band filters allow us to reach the surface brightness level of 28m/□″ when investigating the stellar content of galaxy disks for a sample of nine galaxies. We used observations performed with the 1-m telescope in five broadband (SDSS u, g, r, i, and z) and 15 intermediate-band filters (4000–7500 Å) to construct a sample of quasar candidates with 0.5 < z < 5 (330 objects) in about one-sq. degree SA68 field complete down to RAB = 23m. Spectroscopic observations of 29 objects (19.m5 < R < 22m) carried out at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences confirmed the quasar nature of 28 objects.  相似文献   

5.
We present the results of multicolor (UBV JHKLM) photometry (2009–2017) and low-resolution spectroscopy (2016–2017) of the semi-regular variable V1427 Aql = HD 179821, a yellow supergiant with gas-dust envelope. The star displays low-amplitude (ΔV<0 . m 2) semi-periodic brightness variations superimposed on a long-term trend. The light curve shape and timescale change from cycle to cycle. There are temperature variations characteristic for pulsations; brightness oscillations with no significant change of color are also observed. The UBV data for the 2009–2011 interval are well reproduced by a superposition of two periodic components with P = 170d and 141d (or P = 217d—the one year alias of P = 141d). The variation became less regular after 2011, the timescale increased and exceeded 250d. Unusual photometric behavior was seen in 2015 when the star brightness increased by 0 . m 25 in the V filter in 130 days and reached the maximum value ever observed in the course of our monitoring since 1990. In 2009–2016 the annual average brightness monotonically increased in V, J, K, whereas it decreased in U and B. The annual average U ? B, B ? V, and J ? K colors grew, the star was getting redder. The cooling and expanding of the star photosphere along with the increasing of luminosity may explain the long-term trend in brightness and colors. Based on our photometric data we suppose that the photosphere temperature decreased by ~400 K in the 2008–2016 interval, the radius increased by ~24%, and the luminosity grew by ~19%. We review the change of annual average photometric data for almost 30 years of observations. Low-resolution spectra in the λ4000?9000 Å wavelength range obtained in 2016–2017 indicate significant changes in the spectrum of V1427 Aql as compared with the 1994–2008 interval, i.e., the Ba II and near-infraredCa II triplet absorptions have gotten stronger while the OI λ7771-4 triplet blend has weakened that points out the decrease of temperature in the region where the absorptions are formed. The evolutionary stage of the star is discussed. We also compare V1427 Aql with post-AGB stars and yellow hypergiants.  相似文献   

6.
Results of astrometric and BVRI photometric observations of the active asteroid (596) Scheila are presented. The observations were carried out at the Zeiss-1000 telescope of the Sanglokh International Astronomical Observatory of the Institute of Astrophysics of the Academy of Sciences of the Republic of Tajikistan on June 16?17 and from July 30 to August 1, 2017. The coordinates of the object and its orbit were determined; and the apparent brightness in four filters, the absolute brightness in the V and R filters, and the color indices were obtained. The light curves suggest that no substantial changes in the asteroid’s brightness occurred during the observations. The absolute brightness of the asteroid in the V and R filters was (9.1 ± 0.05)m and (8.8 ± 0.03)m, respectively. The mean value of the asteroid diameter was (119 ± 2) km. The mean values of the color indices (B?V = (0.72 ± 0.05)m, V?R = (0.29 ± 0.03)m, and R?I = (0.31 ± 0.03)m) agree well with the values for asteroids of the P- and D-types and its averages. The rotation period of the asteroid estimated from photometric observations was 16.1 ± 0.2 h. The analysis of the data has shown that the asteroid continues to exhibit the same values of absolute brightness and other characteristics as those before the collision with a small body in December 2010, though the latter resulted in the outburst event and cometary activity of the asteroid. Most likely, the collision of asteroid (596) Scheila with a small body did not lead to catastrophic changes in the surface of the asteroid or to its compete break-up.  相似文献   

7.
Parallaxes with an accuracy better than 10% and proper motions from the Gaia DR1 TGAS catalogue, radial velocities from the Pulkovo Compilation of Radial Velocities (PCRV), accurate Tycho-2 photometry, theoretical PARSEC, MIST, YaPSI, BaSTI isochrones, and the most accurate reddening and interstellar extinction estimates have been used to analyze the kinematics of 9543 thin-disk B-F stars as a function of their dereddened color. The stars under consideration are located on the Hertzsprung–Russell diagram relative to the isochrones with an accuracy of a few hundredths of a magnitude, i.e., at the level of uncertainty in the parallax, photometry, reddening, extinction, and the isochrones themselves. This has allowed us to choose the most plausible reddening and extinction estimates and to conclude that the reddening and extinction were significantly underestimated in some kinematic studies of other authors. Owing to the higher accuracy of TGAS parallaxes than that of Hipparcos ones, the median accuracy of the velocity components U, V, W in this study has improved to 1.7 km s?1, although outside the range ?0.1 m < (B T ? V T )0 < 0.5 m the kinematic characteristics are noticeably biased due to the incompleteness of the sample. We have confirmed the variations in the mean velocity of stars relative to the Sun and the stellar velocity dispersion as a function of their dereddened color known from the Hipparcos data. Given the age estimates for the stars under consideration from the TRILEGAL model and the Geneva–Copenhagen survey, these variations may be considered as variations as a function of the stellar age. A comparison of our results with the results of other studies of the stellar kinematics near the Sun has shown that selection and reddening underestimation explain almost completely the discrepancies between the results. The dispersions and mean velocities from the results of reliable studies fit into a ±2 km s?1 corridor, while the ratios σ V /σ U and σ W /σ U fit into ±0.05. Based on all reliable studies in the range ?0.1 m < (B T ? V T )0 < 0.5m, i.e., for an age from 0.23 to 2.4 Gyr, we have found: W⊙ = 7.15 km s?1, \({\sigma _U} = 16.0{e^{1.29({B_T} - {V_T})o}}\), \({\sigma _V} = 10.9{e^{1.11({B_T} - {V_T})o}}\), \({\sigma _W} = 6.8{e^{1.46({B_T} - {V_T})o}}\), the stellar velocity dispersions in km s?1 are proportional to the age in Gyr raised to the power β U = 0.33, β V = 0.285, and β W = 0.37.  相似文献   

8.
An attempt is made to construct a trial Qμ(l) distribution in the silicate mantle of Mars. With the allowance for the fact that on the P–T plane the Earth’s geotherm is close to the distribution of areotherms, it was concluded that Qμ(l) should be distributed in the Martian interior topologically close to the Qμ(l) distribution in the Earth. The initial distribution was specified by the four-layer piecewise-constant distribution from the QML9 model. An important step was to select the power index in the frequency dependence of Qμ. Based on the laboratory data and on the experience of studying this problem for the Earth, n was specified in the interval 0.1–0.3. It was found that with the conversion of the initial distribution to the orbital period of Phobos around Mars, which is the only constraint for the problem derived from the observations, this distribution agrees reasonably well with the observational data at n = 0.1.  相似文献   

9.
The influence of active processes on the Sun and their response on the dynamics of Earth’s artificial satellites has been investigated. The relationship between the characteristics of solar activity and variations of the periods P of the orbital motion of Earth’s artificial satellites has been found. These variations mainly indicate the variations in the Earth’s atmosphere density caused by solar activity (index F10.7) and geomagnetic activity (ΣKp index). High values of the correlation coefficients between P and F10.7 (–0.77…–0.91) and between P and ΣKp (–0.67…–0.89) exhibit significant effect of solar and geomagnetic activity on the orbital periods of satellites.  相似文献   

10.
The processing of the plates of the Kitab part of the FON project has been completed. In total, 1963 plates were processed. The catalog of equatorial coordinates α, δ, and B-magnitudes for 13 413268 stars and galaxies up to B ≤ 17.5 m for the epoch 1984.97 is compiled. The Epson Expression 10000XL scanner with a 1200 dpi scanning mode and a plate size of 30 × 30 cm or 13000 × 13000 pel was used to digitize astronegatives. Coordinates of stars and galaxies are obtained in the Tycho-2 catalog system and B-magnitudes are obtained in the photovoltaic system. The catalog internal accuracy for all objects is σα,δ = 0.23" and σ B = 0.15 m (for stars in the range B = 5 m …14 m , errors are σα,δ = 0.085" and σ B = 0.054 m ) for equatorial coordinates and stellar B-magnitudes, respectively. Convergence between the calculated and reference positions is σα,δ = 0.042", and convergence between photoelectric B-magnitudes is σ B = 0.16 m . Coordinate errors with respect to the UCAC-4 catalog are σα,δ = 0.26" (9892697 or 73.75% of stars and galaxies were identified).  相似文献   

11.
The paper argues in favor of the assumption that magnetic and non-magnetic protostars, from which CP stars were formed, are the objects that had rotation velocities of the parent cloud V smaller than a critical value V c . At V greater than the critical value, differential rotation emerges in the collapsing protostellar cloud, which twists magnetic lines of force into an’ invisible’ toroidal shape and disturbs the stability of the atmosphere. In magnetic protostars, the loss of angular momentum is due to magnetic braking, while in metallic protostars, the loss of rotation momentum occurs due to tidal interactions with a close component. HgMn stars are most likely not affected by some braking mechanism, but originated from the slowest protostellar rotators. The boundary of V c where the differential rotation occurs is not sharp. The slower the protostar rotates, the greater the probability of suppressing the differential rotation and the more likely the possibility of CP star birth.  相似文献   

12.
Observations of the Earth’s exosphere have unveiled an extended envelope of hydrogen reaching further than 10 Earth radii composed of atoms orbiting around the Earth. This large envelope increases significantly the opacity of the Earth to Lyman α (Lyα) photons coming from the Sun, to the point of making feasible the detection of the Earth’s transit signature from 1.35 pc if pointing with an 8 meter primary mirror space telescope through a clean line of sight (N H <?1017 cm??2), as we show. In this work, we evaluate the potential detectability of Earth analogs orbiting around nearby M-type stars by monitoring the variability of the Lyα flux variability. We show that, in spite of the interstellar, heliospheric and astrospheric absorption, the transit signature in M5 V type stars would be detectable with a dedicated Lyα flux monitor implemented in a 4–8 m class space telescope. Such monitoring programs would enable measuring the robustness of planetary atmospheres under heavy space weather conditions like those produced by M-type stars. A 2-m class telescope, such as the World Space Observatory, would suffice to detect an Earth-like planet orbiting around Proxima Centauri, if there was such a planet or nearby M5 type stars.  相似文献   

13.
We present properties of the low-surface-brightness galaxy KDG218 observed with the HST/ACS. The galaxy has a half-light (effective) diameter of a e = 47″ and a central surface brightness of SB V (0) = 24.m4/□″. The galaxy remains unresolved with the HST/ACS, which implies its distance of D > 13.1 Mpc and linear effective diameter of A e > 3.0 kpc. We notice that KDG218 is most likely associated with a galaxy group around the massive lenticular NGC4958 galaxy at approximately 22 Mpc, or with the Virgo Southern Extension filament at approximately 16.5 Mpc. At these distances, the galaxy is classified as an ultra-diffuse galaxy (UDG) similar to those found in the Virgo, Fornax, and Coma clusters. We also present a sample of 15 UDG candidates in the Local Volume. These sample galaxies have the following mean parameters: 〈D〉 = 5.1 Mpc, 〈A e 〉 = 4.8 kpc, and 〈SB B (e)〉 = 27.m4/□″. All the local UDG candidates reside near massive galaxies located in the regions with the mean stellar mass density (within 1 Mpc) about 50 times greater than the average cosmic density. The local fraction of UDGs does not exceed 1.5% of the Local Volume population. We notice that the presented sample of local UDGs is a heterogeneous one containing irregular, transition, and tidal types, as well as objects consisting of an old stellar population.  相似文献   

14.
Based on the high spectral resolution monitoring conducted at the 6-m BTA telescope, we study the optical spectrum of the high-latitude variable V534 Lyr. Heliocentric radial velocities Vr corresponding to the positions of all metal absorption components, as well as the Na I D and Hα lines were measured during all the observational sets. The analysis of the velocity field examining the lines of various nature revealed a low-amplitude variability of Vr based on the lines with a high excitation potential, which are formed in deep layers of the stellar atmosphere, and allowed to estimate the systemic velocity of Vsys ≈ ?125 kms?1 (Vlsr ≈ ?105 kms?1). The distance estimate of d ≈ 6 kpc for the star leads to its absolute magnitude of \(M_V \approx - 5_ \cdot ^m 3\), what corresponds to the spectral classification. The previously undetected spectral phenomenon was revealed for this star: at certain times a splitting of the profiles of low-excited absorptions is observed, reaching ΔVr = 20–50 kms?1. A combination of the parameters: reduced metallicity [Met/H]⊙ = ?0.28, high nitrogen abundance [N/Fe] = +1.10, large spatial velocity, high luminosity, a strong variability of the emission-absorption profiles of HI lines, splitting of metal absorptions at different times of observations and the variability of the velocity field in the atmosphere allow to classify V534 Lyr as a pulsating star in the thick disk of our Galaxy.  相似文献   

15.
Our goal is to find previously unknown binary systems among low-mass dwarfs in the solar neighborhood and to test the search technique. The basic ideas are to reveal the images of stars with significant ellipticities and/or asymmetries compared to the background stars on CCD frames and to subsequently determine the spatial parameters of the binary system and the magnitude difference between its components. For its realization we have developed a method based on an image shapelet decomposition. All of the comparatively faint stars with large proper motions (V >13 m , μ > 300 mas yr?1) for which the “duplicate source” flag in the Gaia DR1 catalogue is equal to one have been included in the list of objects for our study. As a result, we have selected 702 stars. To verify our results, we have performed additional observations of 65 stars from this list with the Pulkovo 1-m “Saturn” telescope (2016–2017). We have revealed a total of 138 binary candidates (nine of them from the “Saturn” telescope and SDSS data). Six program stars are known binaries. The images of the primaries of the comparatively wide pairs WDS 14519+5147, WDS 11371+6022, and WDS 15404+2500 are shown to be resolved into components; therefore, we can talk about the detection of triple systems. The angular separation ρ, position angle, and component magnitude difference Δm have been estimated for almost all of the revealed binary systems. For most stars 1.5′′ < ρ < 2.5′′, while Δm <1.5m.  相似文献   

16.
An improved version of the 3D stellar reddening map in a space with a radius of 1200 pc around the Sun and within 600 pc of the Galactic midplane is presented. As in the previous 2010 and 2012 versions of the map, photometry with an accuracy better than 0.05 m in the J and Ks bands for more than 70 million stars from the 2MASS catalogue is used in the new version. However, the data reduction technique is considerably more complicated. As before, an analysis of the distribution of stars near the main-sequence turnoff on the (J ? Ks)?Ks diagram, where they form a distribution maximum, provides a basis for the method. The shift of this maximum, i.e., the mode (J ? Ks), along (J ? Ks) and Ks, given the spatial variations of the mean dereddened color (J ? Ks)0 of these stars, is interpreted as a growth of the reddening with increasing distance. The main distinction of the new method is that instead of the fixed mean absolute magnitude, dereddened color, distance, and reddening for each cell, the individual values of these quantities are calculated for each star by iterations when solving the system of equations relating them. This has allowed one to increase the random accuracy of the map to 0.01 m and its spatial resolution to 20 pc in coordinates and distance and to 1° in longitude and latitude. Comparison with other reddening estimates for the same spatial cells and Gaia DR1 TGAS stars shows that the constructed map is one of the best maps for the space under consideration. Its systematic errors have been estimated to be σ(E(J ? Ks)) = 0.025 m , or σ(E(B ? V)) = 0.04 m . The main purpose of the map is to analyze the characteristics of Galactic structures, clouds, and cloud complexes. For this purpose, the reddening map within each spatial cell has also been computed by analyzing the reddening along each line of sight.  相似文献   

17.
The catalogue of protoplanetary nebulae by Vickers et al. has been supplemented with the line-of-sight velocities and proper motions of their central stars from the literature. Based on an exponential density distribution, we have estimated the vertical scale height from objects with an age less than 3 Gyr belonging to the Galactic thin disk (luminosities higher than 5000 L ⊙) to be h = 146 ± 15 pc, while from a sample of older objects (luminosities lower than 5000 L ⊙) it is h = 568 ± 42 pc. We have produced a list of 147 nebulae in which there are only the line-of-sight velocities for 55 nebulae, only the proper motions for 25 nebulae, and both line-of-sight velocities and proper motions for 67 nebulae. Based on this kinematic sample, we have estimated the Galactic rotation parameters and the residual velocity dispersions of protoplanetary nebulae as a function of their age. We have established that there is a good correlation between the kinematic properties of nebulae and their separation in luminosity proposed by Vickers. Most of the nebulae are shown to be involved in the Galactic rotation, with the circular rotation velocity at the solar distance being V 0 = 227 ± 23 km s?1. The following principal semiaxes of the residual velocity dispersion ellipsoid have been found: (σ1, σ2, σ3) = (47, 41, 29) km s?1 from a sample of young protoplanetary nebulae (with luminosities higher than 5000 L ⊙), (σ1, σ2, σ3) = (50, 38, 28) km s?1 from a sample of older protoplanetary nebulae (with luminosities of 4000 L ⊙ or 3500 L ⊙), and (σ1, σ2, σ3) = (91, 49, 36) km s?1 from a sample of halo nebulae (with luminosities of 1700 L ⊙).  相似文献   

18.
We examine the dependence of the total hydrogen mass M HI in late-type star-forming galaxies on rotation velocity V rot and optical size D 25 or radial scale length R 0 of the disk for two samples of galaxies: (i) isolated galaxies (AMIGA) and (ii) galaxies with edge-on disks (flat galaxies according to Karachentsev et al.). M HI given in the HYPERLEDA database for flat galaxies have turned out to be, on average, overestimated by ~0.2 dex compared to isolated galaxies with similar V rot or D 25, which is apparently due to an overestimation of the self-absorption in the HI line. The hydrogen mass in the galaxies of both samples closely correlates with the total specific angular momentum of the galactic disk J, which is proportional to V rot D 25 or V rot R 0, with the low-surface-brightness galaxies lying along the common V rot R 0 sequence. We discuss the possibility of explaining the relationship between M HI and V rot D 25 by assuming that the gas mass in the disk is regulated by the marginal gravitational stability condition for the gas layer. Comparison of the observed and theoretically expected dependences leads us to conclude that either the gravitational stability corresponds to higher values of the Toomre parameter than is usually assumed, or the threshold stability condition formost galaxies was fulfilled only in the past, when the gasmass in the disks was a factor of 2–4 higher than that at present (except for the galaxies with an anomalously high observed HI content). The latter condition requires that for most galaxies the conversion of gas into stars be not compensated by the external accretion of gas onto the disk.  相似文献   

19.
We have selected and analyzed a sample of OB stars with known line-of-sight velocities determined through ground-based observations and with trigonometric parallaxes and propermotions from the Gaia DR2 catalogue. Some of the stars in our sample have distance estimates made from calcium lines. A direct comparison with the trigonometric distance scale has shown that the calcium distance scale should be reduced by 13%. The following parameters of the Galactic rotation curve have been determined from 495 OB stars with relative parallax errors less than 30%: (U, V,W)⊙ = (8.16, 11.19, 8.55)± (0.48, 0.56, 0.48) km s?1, Ω0 = 28.92 ± 0.39 km s?1 kpc?1, Ω'0 = ?4.087 ± 0.083 km s?1 kpc?2, and Ω″ 0 = 0.703 ± 0.067 km s?1 kpc?3, where the circular velocity of the local standard of rest is V0 = 231 ± 5 km s?1 (for the adopted R0 = 8.0 ± 0.15 kpc). The parameters of the Galactic spiral density wave have been found from the series of radial, VR, residual tangential, ΔVcirc, and vertical, W, velocities of OB stars by applying a periodogram analysis. The amplitudes of the radial, tangential, and vertical velocity perturbations are fR = 7.1± 0.3 km s?1, fθ = 6.5 ± 0.4 km s?1, and fW = 4.8± 0.8 km s?1, respectively; the perturbation wavelengths are λR = 3.3 ± 0.1 kpc, λθ = 2.3 ± 0.2 kpc, and λW = 2.6 ± 0.5 kpc; and the Sun’s radial phase in the spiral density wave is (χ⊙)R = ?135? ± 5?, (χ⊙)θ = ?123? ± 8?, and (χ⊙)W = ?132? ± 21? for the adopted four-armed spiral pattern.  相似文献   

20.
The paper presents results of measurements of magnetic-field longitudinal components B e , radial velocities V r , and projections of the rotation velocity in the line of sight v e sin i for 74 objects, mainly main-sequence chemically peculiar stars and standard stars. Observations were carried out in 2011 at the 6-m BTA telescope using the Main Stellar Spectrograph (MSS) with a Zeeman analyzer. Seven new magnetic stars were discovered: HD38129, HD47152, HD50341, HD63347, HD188501, HD191287, and HD260858. Three more stars were suspected to have magnetic fields. Observations of magnetic standard stars and non-magnetic stars confirm the absence of any systematic errors capable of introducing distortions into the B e longitudinal-field measurement results. The paper gives comments on the research results for each of the 74 stars.  相似文献   

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