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931. Properties of Galactic Be Supergiants. VI.
ID:
ivo://CDS.VizieR/J/ApJ/897/48
Title:
Properties of Galactic Be Supergiants. VI.
Short Name:
J/ApJ/897/48
Date:
11 Mar 2022
Publisher:
CDS
Description:
We report the results of long-term spectroscopic monitoring of the A-type supergiant with the B[e] phenomenon 3Pup=HD62623. We confirm earlier findings that it is a binary system. The orbital parameters were derived using cross-correlation of the spectra in a range of 4460-4632{AA}, which contains over 30 absorption lines. The orbit was found to be circular with a period of 137.4{+/-}0.1days, radial velocity semiamplitude K1=5.0{+/-}0.8km/s, systemic radial velocity {gamma}=26.4{+/-}2.0km/s, and mass function f(m)=(1.81_-0.76_^+0.97^)x10^-3^M{sun}. The object may have evolved from a pair with initial masses of ~6.0M{odot} and ~3.6M{sun} with an initial orbital period of ~5days. Based on the fundamental parameters of the A-supergiant (luminosity log L/L{sun}=4.1{+/-}0.1 and effective temperature Teff=8500{+/-}500K) and evolutionary tracks of mass-transferring binaries, we found current masses of the gainer M2=8.8{+/-}0.5M{sun} and donor M1=0.75{+/-}0.25M{sun}. We also modeled the object's IR-excess and derived a dust mass of ~5x10^-5^M{sun} in the optically thin dusty disk. The orbital parameters and properties of the H{alpha} line profile suggest that the circumstellar gaseous disk is predominantly circumbinary. The relatively low mass of the gainer led us to a suggestion that 3 Pup should be excluded from the B[e] supergiant group and moved to the FSCMa group. Overall these results further support our original suggestion that FSCMa objects are binary systems, where an earlier mass transfer caused formation of the circumstellar envelope.
932. Properties of OH/IR stars with IRAS LRS spectra
ID:
ivo://CDS.VizieR/J/A+A/368/1006
Title:
Properties of OH/IR stars with IRAS LRS spectra
Short Name:
J/A+A/368/1006
Date:
21 Oct 2021
Publisher:
CDS
Description:
This table contains the selected from the literature sample of 1065 OH maser sources with IRAS identification and LRS spectra. The most important physical quantities of these sources are assembled and the list of related references together with the abbreviations used is attached.
933. Properties of Spitzer c2d dark clouds
ID:
ivo://CDS.VizieR/J/ApJS/181/321
Title:
Properties of Spitzer c2d dark clouds
Short Name:
J/ApJS/181/321
Date:
21 Oct 2021
Publisher:
CDS
Description:
The c2d Spitzer Legacy project obtained images and photometry with both IRAC and MIPS instruments for five large, nearby molecular clouds. Three of the clouds were also mapped in dust continuum emission at 1.1mm, and optical spectroscopy has been obtained for some clouds. This paper combines information drawn from studies of individual clouds into a combined and updated statistical analysis of star-formation rates and efficiencies, numbers and lifetimes for spectral energy distribution (SED) classes, and clustering properties. Current star-formation efficiencies range from 3% to 6%; if star formation continues at current rates for 10Myr, efficiencies could reach 15-30%. Star-formation rates and rates per unit area vary from cloud to cloud; taken together, the five clouds are producing about 260M_{sun}_ of stars per Myr.
934. Protoclusters and subclusters
ID:
ivo://CDS.VizieR/J/other/ApSS/344.175
Title:
Protoclusters and subclusters
Short Name:
J/other/ApSS/344
Date:
21 Oct 2021
Publisher:
CDS
Description:
A hybrid JHKs - W1W2W3W4 high-spectral index ({alpha}) selection scheme was employed to identify (sub)clusters of class I/f candidate protostars (YSOs) in WISE observations (the Wide-Field Infrared Survey Explorer). n>10^4^ candidate YSOs were detected owing to WISE's advantageous all-sky spatial coverage, and a subsample (n~200) of their heavily-obscured host (sub)clusters were correlated with the Avedisova (2002, Cat. V/112) and Dias et al. (2002A&A...389..871D, Cat. B/ocl) catalogs of star-forming regions. Forthcoming observations from the VVV/UKIDSS surveys shall facilitate the detection of additional protostars and bolster efforts to delineate the Galactic plane, since the campaigns aim to secure deep JHKs photometry for a pertinent fraction of the WISE targets lacking 2MASS detections, and to provide improved data for YSOs near the limits of the 2MASS survey.
935. Protoplanetary disk masses in Taurus
ID:
ivo://CDS.VizieR/J/AJ/157/144
Title:
Protoplanetary disk masses in Taurus
Short Name:
J/AJ/157/144
Date:
21 Oct 2021
Publisher:
CDS
Description:
Measuring the masses of protoplanetary disks is crucial for understanding their planet-forming potential. Typically, dust masses are derived from (sub-)millimeter flux density measurements plus assumptions for the opacity, temperature, and optical depth of the dust. Here we use radiative transfer models to quantify the validity of these assumptions with the aim of improving the accuracy of disk dust mass measurements. We first carry out a controlled exploration of disk parameter space. We find that the disk temperature is a strong function of disk size, while the optical depth depends on both disk size and dust mass. The millimeter-wavelength spectral index can be significantly shallower than the naive expectation due to a combination of optical depth and deviations from the Rayleigh-Jeans regime. We fit radiative transfer models to the spectral energy distributions (SEDs) of 132 disks in the Taurus-Auriga region using a Markov chain Monte Carlo approach. We used all available data to produce the most complete SEDs used in any extant modeling study. We perform the fitting twice: first with unconstrained disk sizes and again imposing the disk size-brightness relation inferred for sources in Taurus. This constraint generally forces the disks to be smaller, warmer, and more optically thick. From both sets of fits, we find disks to be ~1-5 times more massive than when derived using (sub-)millimeter measurements and common assumptions. With the uncertainties derived from our model fitting, the previously measured dust mass-stellar mass correlation is present in our study but only significant at the 2{sigma} level.
936. Protostars in Perseus, Serpens and Ophiuchus
ID:
ivo://CDS.VizieR/J/ApJ/692/973
Title:
Protostars in Perseus, Serpens and Ophiuchus
Short Name:
J/ApJ/692/973
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an unbiased census of deeply embedded protostars in Perseus, Serpens, and Ophiuchus, assembled by combining large-scale 1.1mm Bolocam continuum and Spitzer Legacy surveys. We identify protostellar candidates based on their mid-infrared (mid-IR) properties, correlate their positions with 1.1mm core positions from Enoch et al. in 2006 (Cat. J/ApJ/638/293) and 2007ApJ...666..982E, and Young et al. in 2006ApJ...644..326Y, and construct well-sampled spectral energy distributions using our extensive wavelength coverage ({lambda}=1.25-1100um). Source classification based on the bolometric temperature yields a total of 39 Class 0 and 89 Class I sources in the three-cloud sample. We compare to protostellar evolutionary models using the bolometric temperature-luminosity diagram, finding a population of low-luminosity Class I sources that are inconsistent with constant or monotonically decreasing mass accretion rates.
937. PSCz catalog
ID:
ivo://CDS.VizieR/VII/221
Title:
PSCz catalog
Short Name:
VII/221
Date:
21 Oct 2021
Publisher:
CDS
Description:
The PSCz survey consists of redshifts, infra-red and optical photometry, and assorted other information for 18351 IRAS sources, mostly selected from the Point Source Catalog. The survey was designed to select almost all galaxies with flux brighter than 0.595Jy at 60 microns, over the 84% of the sky with extinction small enough that reliable and complete optical identification and spectroscopy was possible. Some of the sources are not galaxies and some are multiple entries for the same galaxy as described below. There are in total 15411 galaxies or possible galaxies, for which redshifts are available for 14677. The galaxies without redshift are mostly distant or at low latitude, as described below. Many of these galaxies have now been observed as part of the BTP project (Saunders et al 1999, astro-ph/9909174 "The Behind the Plane Survey"), and their redshifts will be included in future revisions of the catalogue. The main catalogue is "pscz.dat". There is also a short version of the catalogue, "psczvs.dat", containing sufficient information for most studies. They correspond to the version 2.2.
938. PSR J1023+0038 VLT, XM and Swift observations
ID:
ivo://CDS.VizieR/J/A+A/631/A104
Title:
PSR J1023+0038 VLT, XM and Swift observations
Short Name:
J/A+A/631/A104
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on a simultaneous near-infrared, optical, and X-ray campaign performed in 2017 with the XMM-Newton and Swift satellites and the HAWK-I instrument mounted on the Very Large Telescope (VLT) on the transitional millisecond pulsar PSR J1023+0038. Near-infrared observations were performed in fast-photometric mode (0.5s exposure time) in order to detect any fast variation of the flux and correlate this with the optical and X-ray light curves. The optical light curve shows the typical sinusoidal modulation at the system orbital period (4.75hr). No significant flaring or flickering is found in the optical, nor any signs of transitions between active and passive states. On the contrary, the near-infrared light curve displays a bimodal behaviour, showing strong flares in the first part of the curve, and an almost flat trend in the rest. The X-ray light curves instead show a few low-high mode transitions, but no flaring activity is detected. Interestingly, one of the low-high mode transitions occurs at the same time as the emission of an infrared flare. This can be interpreted in terms of the emission of an outflow or a jet: the infrared flare could be due to the evolving spectrum of the jet, which possesses a break frequency that moves from higher (near-infrared) to lower (radio) frequencies after the launching, which has to occur at the low-high mode transition. We also present the cross-correlation function between the optical and near-infrared curves. The near.infrared curve is bimodal, therefore we divided it into two parts (flaring and quiet). While the cross-correlation function of the quiet part is found to be flat, the function that refers to the flaring part shows a narrow peak at 10s, which indicates a delay of the near-infrared emission with respect to the optical. This lag can be interpreted as reprocessing of the optical emission at the light cylinder radius with a stream of matter spiraling around the system due to a phase of radio ejection. This strongly supports a different origin of the infrared flares that are observed for PSR J1023+0038 with respect to the optical and X-ray flaring activity that has been reported in other works on the same source.
939. PTI calibrator catalog
ID:
ivo://CDS.VizieR/J/ApJS/176/276
Title:
PTI calibrator catalog
Short Name:
J/ApJS/176/276
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Palomar Testbed Interferometer (PTI) archive of observations between 1998 and 2005 is examined for objects appropriate for calibration of optical long-baseline interferometer observations - stars that are predictably pointlike and single. Approximately 1400 nights of data on 1800 objects were examined for this investigation. We compare those observations to an intensively studied object that is a suitable calibrator, HD 217014, and statistically compare each candidate calibrator to that object by computing both a Mahalanobis distance and a principal component analysis. Our hypothesis is that the frequency distribution of visibility data associated with calibrator stars differs from noncalibrator stars such as binary stars. Spectroscopic binaries resolved by PTI, objects known to be unsuitable for calibrator use, are similarly tested to establish detection limits of this approach. From this investigation, we find more than 350 observed stars suitable for use as calibrators (with an additional ~140 being rejected), corresponding to >~95% sky coverage for PTI.
940. PTI carbon star angular size survey
ID:
ivo://CDS.VizieR/J/ApJ/775/45
Title:
PTI carbon star angular size survey
Short Name:
J/ApJ/775/45
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report new interferometric angular diameter observations of 41 carbon stars observed with the Palomar Testbed Interferometer. Two of these stars are CH carbon stars and represent the first such measurements of this subtype. Of these, 39 have Yamashita spectral classes and are of sufficiently high quality that we can determine the dependence of effective temperature on spectral type. We find that there is a tendency for the effective temperature to increase with increasing temperature index by ~120K per step, starting at T_eff_=~2500K for C3, y, although there is a large amount of scatter in this relationship. Overall, the median effective temperature of the carbon star sample is 2800+/-270 K and the median linear radius is 360+/-100R_{sun}_. We also find agreement, on average within 15K, with the T_eff_ determinations of Bergeat et al. (J/A+A/369/178) and a refinement of the carbon star angular size prediction based on V & K magnitudes is presented that is good to an rms of 12%. A subsample of our stars have sufficient {u, v} coverage to permit non-spherical modeling of their photospheres, and a general tendency for detection of statistically significant departures from sphericity with increasing interferometric signal-to-noise is seen. The implications of most -and potentially all- carbon stars being non-spherical is considered in the context of surface inhomogeneities and a rotation-mass-loss connection.