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- ID:
- ivo://CDS.VizieR/J/A+AS/137/351
- Title:
- A supergiants UV and visible spectra
- Short Name:
- J/A+AS/137/351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is the first of a series whose aim is to perform a systematic study of A-type supergiant atmospheres and winds. Here we present a spectral atlas of 41 A-supergiants observed by us in high and medium resolution in the visible and ultraviolet. The atlas consists of profiles of the H{alpha}, H{beta}, H{gamma}, H{delta}, H{epsilon}, Ca II (H and K), Na I (D1 and D2), Mg II_4481_, Mg II [uv1] and Fe II [uv1, uv2, uv3, uv62, uv63, uv161] lines for 41 stars with spectral types ranging from B9 to A9 and luminosity classes Ia, Iab and Ib, and provides the basic data for a thoughtful study of these stars. The overall characteristics of the sample as well as the data reduction procedures are described. We also present some examples of spectral variability.
- ID:
- ivo://CDS.VizieR/J/ApJ/784/154
- Title:
- A survey for H{alpha} pulsar bow shocks
- Short Name:
- J/ApJ/784/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on a survey for H{alpha} bow shock emission around nearby {gamma}-detected energetic pulsars. This survey adds three Balmer-dominated neutron star bow shocks to the six previously confirmed examples. In addition to the shock around Fermi pulsar PSR J1741-2054, we now report H{alpha} structures around two additional {gamma}-ray pulsars, PSR J2030+4415 and PSR J1509-5850. These are the first known examples of H{alpha} nebulae with pre-ionization halos. With new measurements, we show that a simple analytic model can account for the angular size and flux of the bow shocks' apices. The latter, in particular, provides a new pulsar probe and indicates large moments of inertia and smaller distances than previously assumed in several cases. In particular, we show that the re-measured PSR J0437-4715 shock flux implies I=(1.7+/-0.2)x10^45^/(f_H I_sin i)g cm^2^. We also derive a distance d~0.72 kpc for the {gamma}-ray only pulsar PSR J2030+4415 and revised distances for PSRs J1959+2048 (1.4 kpc) and J2555+6535 (~1 kpc), smaller than the conventional DM-estimated values. Finally, we report upper limits for 94 additional LAT pulsars. An estimate of the survey sensitivity indicates that for a warm neutral medium filling factor {phi}_WNM_~0.3 there should be a total of approximately nine H{alpha} bow shocks in our LAT-targeted survey; given that seven such objects are now known, a much larger {phi}_WNM_ seems problematic.
- ID:
- ivo://CDS.VizieR/J/A+A/487/539
- Title:
- A survey for quasars near quasars - QNQ
- Short Name:
- J/A+A/487/539
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of our slitless spectroscopic survey for quasars near 18 known high-redshift quasars (QNQ). The three tables list the survey fields (26.2'x33.5'), the newly confirmed quasars and the remaining unconfirmed quasar candidates, respectively. For each confirmed quasar we give the equatorial coordinates, the redshift measured from the follow-up slit spectra, the redshift uncertainty and the Johnson B magnitude with uncertainty. The redshift uncertainty has been determined from the redshift dispersions of several emission lines. For the remaining candidates we list the equatorial coordinates, the approximate V magnitude, the redshift based on the slitless spectrum and our assessment of the redshift confidence.
- ID:
- ivo://CDS.VizieR/J/A+AS/113/539
- Title:
- A survey of carbon stars in the SMC
- Short Name:
- J/A+AS/113/539
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey of carbon stars in the outer parts of the Small Magellanic Cloud has been completed; the candidate objects were identified by inspecting UK Schmidt Telescope objective-prism plates which cover a total area of ~220 sq deg on the sky, including the inter-Cloud region. Co-ordinates are given for 1185 newly identified carbon stars.
- ID:
- ivo://CDS.VizieR/J/A+AS/31/439
- Title:
- A Survey of HII Regions in M31
- Short Name:
- J/A+AS/31/439
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An H-alpha survey, using a focal reducer and narrow-band interference filters, has resulted in the detection of nearly a thousand HII regions in M31. The catalog gives their positions, dimensions, and surface brightnesses. The surface brightnesses are on an absolute scale; the photographic measures were calibrated by using photoelectric measures from two different sources. The detection limit reached corresponds to an emission measure of 40cm^-6^pc at a temperature of 10000K.
- ID:
- ivo://CDS.VizieR/VIII/58
- Title:
- A Survey of Radio H II Regions in the Northern Sky
- Short Name:
- VIII/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Nearly 500 radio continuum sources near the Galactic plane at declinations greater than -37 degrees were examined for radio recombination line emission to see if they might be HII regions. A total of 462 were detected, about half of these for the first time. The data are presented in an extensive table. Among the newly discovered nebulae are several with recombinations lines so narrow that their electron temperature must be less than 4600 K. In one case the line width (in several transitions) is only 11.6 km/s, requiring electron temperatures less than about 2900 K.
- ID:
- ivo://CDS.VizieR/J/ApJS/190/1
- Title:
- A survey of stellar families
- Short Name:
- J/ApJS/190/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a comprehensive assessment of companions to solar-type stars. A sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with {pi}>40mas, {sigma}{pi}/{pi}<0.05, 0.5<=B-V<=1.0 (~F6-K3), and constrained by absolute magnitude and color to exclude evolved stars. These criteria are equivalent to selecting all dwarf and subdwarf stars within 25pc with V-band flux between 0.1 and 10 times that of the Sun, giving us a physical basis for the term "solar-type". New observational aspects of this work include surveys for (1) very close companions with long-baseline interferometry at the Center for High Angular Resolution Astronomy Array, (2) close companions with speckle interferometry, and (3) wide proper-motion companions identified by blinking multi-epoch archival images. In addition, we include the results from extensive radial-velocity monitoring programs and evaluate companion information from various catalogs covering many different techniques. The results presented here include four new common proper-motion companions discovered by blinking archival images. Additionally, the spectroscopic data searched reveal five new stellar companions. Our synthesis of results from many methods and sources results in a thorough evaluation of stellar and brown dwarf companions to nearby Sun-like stars. The overall observed fractions of single, double, triple, and higher-order systems are 56%+/-2%, 33%+/-2%, 8%+/-1%, and 3%+/-1%, respectively, counting all confirmed stellar and brown dwarf companions.
- ID:
- ivo://CDS.VizieR/J/AJ/152/111
- Title:
- A 2011-2013 survey of trans-Neptunian objects
- Short Name:
- J/AJ/152/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The trans-Neptunian objects (TNOs) preserve evidence of planet building processes in their orbital and size distributions. While all populations show steep size distributions for large objects, a relative deficit of Neptunian trojans and scattering objects with diameters of D<100km has been detected. We investigated this deficit with a 32 square degree survey, in which we detected 77 TNOs that are brighter than a limiting r-band magnitude of 24.6. Our plutino sample (18 objects in 3:2 mean-motion resonance with Neptune) shows a deficit of D<100km objects, rejecting a single power-law size distribution at >99% confidence. Combining our survey with the Canada-France Ecliptic Plane Survey, we perform a detailed analysis of the allowable parameters for the plutino size distribution, including knees and divots. We surmise the existence of 9000+/-3000 plutinos with an absolute magnitude of H_r_{<=}8.66 and 37000_-10000_^+12000^ with H_r_{<=}10.0 (95% confidence). Our survey also discovered one temporary Uranian trojan, one temporary Neptunian trojan, and one stable Neptunian trojan, for which we estimate populations of 110_-100_^+500^, 210_-200_^+900^, and 150_-140_^+600^ with H_r_{<=}10.0, respectively. All three populations are thus less numerous than the main belt asteroids (592 asteroids with H_r_{<=}10.0). With such population sizes, the temporary Neptunian trojans cannot be previously stable trojans diffusing out of the resonance now; they must be recently captured Centaurs or scattering objects. As the bias against the detection of objects grows with larger semimajor axes, our discovery of three 3:1 resonators and one 4:1 resonator adds to the growing evidence that the high-order resonances are far more populated than is typically predicted.
- ID:
- ivo://CDS.VizieR/J/AJ/127/1567
- Title:
- Asymmetric thick disk. II. Kinematics
- Short Name:
- J/AJ/127/1567
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a kinematic signature associated with the observed asymmetry in the distribution of thick-disk/inner halo stars interior to the solar circle described in Paper I (Parker et al., 2003AJ....126.1346P). In that paper, we found a statistically significant excess (20%-25%) of stars in quadrant I (l~20{deg}-55{deg}) both above and below the plane (b~+/-25{deg} to b~+/-45{deg}) compared with the complementary region in quadrant IV. We have measured Doppler velocities for 741 stars, selected according to the same magnitude and color criteria, in the direction of the asymmetry and in the corresponding fields in quadrant IV. We have also determined spectral types and metallicities measured from the same spectra.
