- ID:
- ivo://CDS.VizieR/J/ApJ/872/158
- Title:
- Survey of Class II sources in Taurus with ALMA
- Short Name:
- J/ApJ/872/158
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a survey of young single and multiple systems in the Taurus-Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separations as small as 25-30au and have an average 3{sigma} detection level of 0.35mJy, equivalent to a disk mass of 4x10^-5^M_{sun}_ for an M3 star. Our sample was constructed from stars that have an infrared excess and/or signs of accretion and have been classified as Class II. For the binary and higher-order multiple systems observed, we detect {lambda}=1.3mm continuum emission from one or more stars in all of our target systems. Combined with previous surveys of Taurus, our 21 new detections increase the fraction of millimeter-detected disks to over 75% in all categories of stars (singles, primaries, and companions) earlier than spectral type M6 in the Class II sample. Given the wealth of other information available for these stars, this has allowed us to study the impact of multiplicity with a much larger sample. While millimeter flux and disk mass are related to stellar mass as seen in previous studies, we find that both primary and secondary stars in binary systems with separations of 30-4200au have lower values of millimeter flux as a function of stellar mass than single stars. We also find that for these systems, the circumstellar disk around the primary star does not dominate the total disk mass in the system and contains on average 62% of the total mass.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/725
- Title:
- Survey of diffuse interstellar bands
- Short Name:
- J/MNRAS/423/725
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents an atlas of diffuse interstellar bands together with tables with measurements of their parameters: central wavelengths, full widths at half-maximum and equivalent widths. For this goal the spectra of ten reddened, early-type stars have been selected. The spectra are of high resolution, ~100000, and reasonable signal-to-noise ratio, S/N>300; they cover a wide spectral range 3500-10000{AA} and show a lack of evident Doppler splitting in the interstellar KI line. The measurement technique has allowed a homogeneous set of data to be achieved. As a result, the identity of 336 DIBs from previous surveys has been confirmed and 21 new bands have been found.
21173. Survey of 108 E-S0 galaxies
- ID:
- ivo://CDS.VizieR/VII/184
- Title:
- Survey of 108 E-S0 galaxies
- Short Name:
- VII/184
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey has been performed of the morphological and photometric properties of 108 E-S0 galaxies out of a complete sample of 112: this sample is built from the Revised Shapley-Ames Catalogue (RSA) keeping objects with {delta}>-10deg and V_0_<3000km/s, rejecting SB0's and Local Group dwarfs. The data were mainly derived from our CCD observations at Observatoire de Haute-Provence: the camera allowed fields of 4x7arcmin (or 7x7 from the last run), the seeing being generally in the 2-3arcsec FWHM range. The measurements include the isophotal analysis according to Carter's (1978) principles, and the photometric profiles along the two main axis. Opposite semi-axis are measured separately to detect asymmetries.
- ID:
- ivo://CDS.VizieR/J/MNRAS/253/686
- Title:
- Survey of faint compact objects
- Short Name:
- J/MNRAS/253/686
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a low-resolution (73A) spectroscopic survey of faint compact objects conducted with the Low Dispersion Survey Spectrograph at the Anglo-Australian Telescope. The sample is a random subset of all compact sources with 22.5<=b_j_<=23.5 in three high-latitude fields. Additional data on compact sources with 21<=b_j_<=22.5 have been selected from the higher resolution (13A) survey previously published by Colless et al. (1990), and a subset of these brighter objects has been studied at both dispersions.
- ID:
- ivo://CDS.VizieR/III/7A
- Title:
- Survey of faint OB stars in Carina
- Short Name:
- III/7A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A finding list is presented for OB stars in a 75 square degree region centered on {eta} Carinae, observed with the the 50/65/175cm Schmidt telescope of the Uppsala Southern Station at Mount Stromlo, with an objective prism giving a dispersion of 470Angstrom/mm et H{gamma}. Completeness between 8.5 and 11.5 was the goal. Accurate positions were added by Brian Skiff (Lowell Observatory) on 2003-Aug-18 for non-HD/CPD stars, and on 2009-12-29 for all stars; the result is the file "positions.dat". Coordinates were found with VizieR usually from UCAC2 or Tycho-2. V magnitudes were added from published photoelectric data, ASAS-3, or Tycho-2. In the remarks the CD names were added if available for CPD stars. The implicit spectral type is 'OB', but some follow-up observations from other sources, notably by Graham himself (1970AJ.....75..703G) show that some of the stars are of later type.
- ID:
- ivo://CDS.VizieR/J/ApJS/155/421
- Title:
- Survey of Galactic Center region at 20cm
- Short Name:
- J/ApJS/155/421
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first in a series of papers presenting a sensitive 20cm VLA continuum survey of the Galactic center region using new and archival data based on multiconfiguration observations taken with relatively uniform uv coverage. The high dynamic range images cover the regions within -2{deg}<l<5{deg} and -40'<b<40' with a spatial resolution of ~30" and 10". The wide field imaging technique is used to construct a low-resolution mosaic of 40 overlapping pointings. The mosaic image includes the Effelsberg observations filling the low spatial frequency uv data. We also present high-resolution images of 23 overlapping fields using DnC and CnB array configurations. These high-resolution images are sensitive to both compact and extended continuum features with a wide range of angular scales with rms noise of 0.2mJy/beam in the outer parts of the Galactic center region. The survey has resulted in a catalog of 345 discrete sources as well as 140 images revealing structural details of HII regions, supernova remnants, pulsar wind nebulae, and more than 80 linear filaments distributed toward the complex region of the Galactic center.
- ID:
- ivo://CDS.VizieR/J/AJ/119/32
- Title:
- Survey of galaxies within nearby voids. II
- Short Name:
- J/AJ/119/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the optical properties of {~}300 galaxies within and around three prominent voids of the Center for Astrophysics Redshift Survey. We determine CCD morphologies and H{alpha} equivalent widths from our imaging and spectroscopic survey. We also describe a redshift survey of 250 neighboring galaxies in the imaging survey fields. We assess the morphology-density relation, EW(H{alpha})-density relation, and the effects of nearby companions for galaxies in low-density environments selected with a smoothed large-scale (5 h^-1^ Mpc) galaxy number density n.
- ID:
- ivo://CDS.VizieR/J/AJ/118/2561
- Title:
- Survey of galaxies within prominent nearby voids
- Short Name:
- J/AJ/118/2561
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the optical properties of a large sample of galaxies in low-density regions of the nearby universe. We make a 5 h^-1^ Mpc smoothed map of the galaxy density throughout the Center for Astrophysics Redshift Survey (CfA2) to identify galaxies within three prominent nearby "voids" with diameter {>=} 30 h^-1^ Mpc. We augment the CfA2 void galaxy sample with fainter galaxies found in the same regions from the more recent and deeper Century and Redshift surveys. We obtain B and R CCD images and high signal-to-noise long-slit spectra for the resulting sample of 149 void galaxies, as well as for an additional 131 galaxies on the periphery of these voids. Here we describe the photometry for the sample, including B isophotal magnitudes and B-R colors.
- ID:
- ivo://CDS.VizieR/J/ApJ/526/788
- Title:
- Survey of infall motions toward starless cores
- Short Name:
- J/ApJ/526/788
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a survey of 220 starless cores selected primarily by their optical obscuration and observed in CS (2-1), N_2_H^+^ (1-0), and C^18^O (1-0) using the Northeast Radio Observatory Corporation (NEROC) Haystack 37 m telescope. We have detected 163 out of 196 sources observed in CS, 72 out of 142 in N_2_H^+^, and 30 out of 30 in C18O. In total, 69 sources were detected in both CS and N_2_H^+^. The isolated component of the N_2_H^+^ (1-0) spectrum (F_1_F = 0,1-1,2) usually shows a weak symmetric profile that is optically thin. In contrast, a significant fraction of the CS spectra show non-Gaussian shapes, which we interpret as arising from a combination of self-absorption due to lower excitation gas in the core front and kinematics in the core. The distribution of the normalized velocity difference ({delta}V_CS_) between the CS and N_2_H^+^ peaks appears significantly skewed to the blue (V_CS_ < 0), as was found in a similar study of dense cores with embedded young stellar objects (YSOs). The incidence of sources with blue asymmetry tends to increase as the total optical depth or the integrated intensity of the N_2_H^+^ line increases.
- ID:
- ivo://CDS.VizieR/J/ApJ/680/495
- Title:
- Survey of Interstellar clouds in the Gould belt
- Short Name:
- J/ApJ/680/495
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of two areas totalling 0.57deg^2^ in the IC 5146 star-forming region at 3.6, 4.5, 5.8, 8.0, 24, and 70um observed with the Spitzer Space Telescope. We reexamine the issue of the distance to this cloud and conclude a value of 950+/-80pc is most likely. We compare source counts, colors, and magnitudes in our observed region to a subset of the SWIRE data that was processed through our pipeline. We identify more than 200 young stellar object (YSO) candidates from color-magnitude and color-color diagrams, many of which were previously unknown. We compare the colors of these YSOs to the models of Robitaille et al. and perform simple fits to the SED's to estimate properties of the circumstellar disks likely to surround the Class II and III sources. We also compare the mid-IR disk excesses to H{alpha} emission-line data where available. We present a quantitative description of the degree of clustering, estimate the star formation efficiency, and discuss the fraction of YSOs in the region with disks relative to an estimate of the diskless YSO population. Finally, we compare the YSO distribution to the cold dust distribution mapped by SCUBA and briefly describe the diffuse emission likely due to PAHs associated with the HII region.
