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6531. Survey of Centaurus A's Baryonic Structures II.
ID:
ivo://CDS.VizieR/J/MNRAS/469/3444
Title:
Survey of Centaurus A's Baryonic Structures II.
Short Name:
J/MNRAS/469/3444
Date:
21 Oct 2021
Publisher:
CDS
Description:
New wide-field u'g'r'i'z' Dark Energy Camera observations centred on the nearby giant elliptical galaxy NGC 5128 covering ~21 deg^2^ are used to compile a new catalogue of ~3200 globular clusters (GCs). We report 2404 newly identified candidates, including the vast majority within ~140kpc of NGC 5128. We find evidence for a transition at a galactocentric radius of R_gc_~=55kpc from GCs 'intrinsic' to NGC 5128 to those likely to have been accreted from dwarf galaxies or that may transition to the intragroup medium of the Centaurus A galaxy group. We fit power-law surface number density profiles of the form {Sigma}_N,R_gc_{prop.to}R_gc_^{Gamma}^ and find that inside the transition radius, the red GCs are more centrally concentrated than the blue, with {Gamma}_inner,red_~=-1.78 and {Gamma}_inner,blue_~=-1.40, respectively. Outside this region both profiles flatten, more dramatically for the red GCs ({Gamma}_outer,red_~=-0.33) compared to the blue ({Gamma}_outer,blue_~= -0.61), although the former is more likely to suffer contamination by background sources. The median (g'-z')_0_=1.27mag colour of the inner red population is consistent with arising from the amalgamation of two giant galaxies each less luminous than present-day NGC 5128. Both inwards and outwards of the transition radius, we find the fraction of blue GCs to dominate over the red GCs, indicating a lively history of minor mergers. Assuming the blue GCs to originate primarily in dwarf galaxies, we model the population required to explain them, while remaining consistent with NGC 5128's present-day spheroid luminosity. We find that several dozen dwarfs of luminosities L_dw,V_~= 10^6-9.3^L_V,{sun}_, following a Schechter luminosity function with a faint-end slope of -1.50<={alpha}<=-1.25 is favoured, many of which may have already been disrupted in NGC 5128's tidal field.
6532. Survey of Class II sources in Taurus with ALMA
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.
6533. 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.
6534. Survey of galaxies within nearby voids. II
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.
6535. Survey of galaxies within prominent nearby voids
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.
6536. Survey of Interstellar clouds in the Gould belt
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.
6537. Survey of M31 with Spitzer
ID:
ivo://CDS.VizieR/J/ApJ/687/230
Title:
Survey of M31 with Spitzer
Short Name:
J/ApJ/687/230
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore the stellar population of M31 in a Spitzer Space Telescope survey utilizing IRAC and MIPS observations. Red supergiants are the brightest objects seen in the infrared; they are a prominent evolutionary phase. Due to their circumstellar envelopes, many of these radiate the bulk of their luminosity at IRAC wavelengths and do not stand out in the near-infrared or optically. Going fainter, we see large numbers of luminous asymptotic giant branch stars (AGB), many of which are known long-period variables. Relative to M33 the AGB carbon star population of M31 appears sparse, but this needs to be spectroscopically confirmed.
6538. Survey of novae in M31
ID:
ivo://CDS.VizieR/J/ApJ/734/12
Title:
Survey of novae in M31
Short Name:
J/ApJ/734/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of a multi-year spectroscopic and photometric survey of novae in M31 that resulted in a total of 53 spectra of 48 individual nova candidates. Two of these, M31N 1995-11e and M31N 2007-11g, were revealed to be long-period Mira variables, not novae. These data double the number of spectra extant for novae in M31 through the end of 2009 and bring to 91 the number of M31 novae with known spectroscopic classifications. We find that 75 novae (82%) are confirmed or likely members of the FeII spectroscopic class, with the remaining 16 novae (18%) belonging to the He/N (and related) classes. These numbers are consistent with those found for Galactic novae. We find no compelling evidence that spectroscopic class depends sensitively on spatial position or population within M31 (i.e., bulge versus disk), although the distribution for He/N systems appears slightly more extended than that for the FeII class. We confirm the existence of a correlation between speed class and ejection velocity (based on line width), as in the case of Galactic novae. Follow-up photometry allowed us to determine light-curve parameters for a total of 47 of the 91 novae with known spectroscopic class. We confirm that more luminous novae generally fade the fastest and that He/N novae are typically faster and brighter than their FeII counterparts. In addition, we find a weak dependence of nova speed class on position in M31, with the spatial distribution of the fastest novae being slightly more extended than that of slower novae.
6539. Survey of optically variables QSOs
ID:
ivo://CDS.VizieR/J/A+A/296/665
Title:
Survey of optically variables QSOs
Short Name:
J/A+A/296/665
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe a survey for variable QSOs carried out for 15 years with the UK Schmidt telescope, using IIIaJ plates exposed behind a Schott GG395 filter. Objects brighter than B=21.0 on a reference plate and displaying a peak to peak amplitude of variability larger than B=0.35mag are selected. Plates in U, V, R and I were also obtained.
6540. Survey of SiO maser emission in oxygen-rich stars
ID:
ivo://CDS.VizieR/J/ApJS/253/44
Title:
Survey of SiO maser emission in oxygen-rich stars
Short Name:
J/ApJS/253/44
Date:
01 Mar 2022 00:16:35
Publisher:
CDS
Description:
Circumstellar environments of oxygen-rich stars are among the strongest SiO maser emitters. Physical processes such as collisions, infrared pumping, and overlaps favor the inversion of level population and produce maser emission at different vibrational states. Despite numerous observational and theoretical efforts, we still do not have a unified picture including all of the physical processes involved in SiO maser emission. The aim of this work is to provide homogeneous data in a large sample of oxygen-rich stars. We present a survey of 67 oxygen-rich stars from 7 to 1mm, in their rotational transitions from J=1-0 to J=5-4, for vibrational numbers v from 0 to 6 in the three main SiO isotopologs. We have used one of the 34 m NASA antennas at Robledo and the IRAM 30m radio telescope. The first tentative detection of a v=6 line is reported, as well as the detection of new maser lines. The highest vibrational levels seem confined to small volumes, presumably close to the stars. The J=1-0, v=2 line flux is greater than the corresponding v=1 in almost half of the sample, which may confirm a predicted dependence on the pulsation cycle. This database is potentially useful in models which should consider most of the physical agents, time dependency, and mass-loss rates. As a by-product, we report detections of 27 thermal rotational lines from other molecules, including isotopologs of SiS, H_2_S, SO, SO_2_, and NaCl.