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881. 12.2 GHz methanol survey
ID:
ivo://CDS.VizieR/J/A+A/413/233
Title:
12.2 GHz methanol survey
Short Name:
J/A+A/413/233
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of 12.2GHz methanol maser survey done with the Torun 32 meter radio telescope. We examined 261 star forming sites, known as containing 6.7GHz maser emission sources. The survey resulted in 49 sources with maser line detection, with 21 previously unknown emissions. All detected 12.2GHz masers have been observed at 6.7GHz transition. Only one 12.2GHz source has no 6.7GHz counterpart. We compared basic spectral line properties at both transitions. In a few cases we observed absorption features and emitting counterparts in the other monitored frequency, at the same velocity.
882. 31.0-50.3 GHz observations of IRC+10216
ID:
ivo://CDS.VizieR/J/A+A/658/A39
Title:
31.0-50.3 GHz observations of IRC+10216
Short Name:
J/A+A/658/A39
Date:
22 Feb 2022
Publisher:
CDS
Description:
The carbon-rich envelope of the asymptotic giant branch star CW Leo, IRC+10216, is one of the richest molecular sources in the sky. Available spectral surveys below 51GHz are more than 25 years old, and new work is needed. Characterizing the rich molecular content of this source, specially for heavy species, requires carrying out very sensitive spectral surveys at low frequencies. In particular, we have achieved an rms in the range 0.2-0.6mK per MHz. Long Q band (31.0-50.3GHz) single-dish integrations were carried out with the Yebes-40m telescope using specifically built receivers. The most recent line catalogs were used to identify the lines. The data contain 652 spectral features, corresponding to 713 transitions from 81 species (we count the isomers, isotopologs, and ortho/para species separately). Only 57 unidentified lines remain with signal-to-noise ratios >=3. Some new species and/or vibrational modes have been discovered for the first time with this survey. This IRC+10216 spectral survey is by far the most sensitive survey carried out to date in the Q band. It therefore provides the most complete view of IRC+10216 from 31.0 to 50.3GHz, giving unique information about its molecular content, especially for heavy species. Rotational diagrams built from the data provide valuable information about the physical conditions and chemical content of this circumstellar envelope.
883. 86GHz SiO maser survey of late-type stars
ID:
ivo://CDS.VizieR/J/A+A/393/115
Title:
86GHz SiO maser survey of late-type stars
Short Name:
J/A+A/393/115
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 86GHz (v=1, J=2-1) SiO maser line observations with the IRAM 30-m telescope of a sample of 444 late-type stars in the Inner Galaxy (-4{deg}<l<+30{deg}). These stars were selected on basis of their infrared magnitudes and colours from the ISOGAL and MSX catalogues. SiO maser emission was detected in 271 sources, and their line-of-sight velocities indicate that the stars are located in the Inner Galaxy. These new detections double the number of line-of-sight velocities available from previous SiO and OH maser observations in the area covered by our survey and are, together with other samples of e.g. OH/IR stars, useful for kinematic studies of the central parts of the Galaxy.
884. 80-116GHz spectrum of L483
ID:
ivo://CDS.VizieR/J/A+A/625/A147
Title:
80-116GHz spectrum of L483
Short Name:
J/A+A/625/A147
Date:
21 Oct 2021
Publisher:
CDS
Description:
An exhaustive chemical characterization of dense cores is mandatory to our understanding of chemical composition changes from a starless to a protostellar stage. However, only a few sources have had their molecular composition characterized in detail. Here we present a 3mm line survey of L483, a dense core around a Class 0 protostar, which was observed with the IRAM 30m telescope in the 80-116GHz frequency range. We detected 71 molecules (140 including different isotopologs), most of which are present in the cold and quiescent ambient cloud according to their narrow lines (FWHM~0.5km/s) and low rotational temperatures (<~10K). Of particular interest among the detected molecules are the cis isomer of HCOOH, the complex organic molecules HCOOCH_3_, CH_3_OCH_3_, and C_2_H_5_OH, a wide variety of carbon chains, nitrogen oxides like N_2_O, and saturated molecules like CH_3_SH, in addition to eight new interstellar molecules (HCCO, HCS, HSC, NCCNH^+^, CNCN, NCO, H_2_NCO^+^, and NS^+^) whose detection has already been reported. In general, fractional molecular abundances in L483 are systematically lower than in TMC-1 (especially for carbon chains), tend to be higher than in L1544 and B1-b, and are similar to those in L1527. Apart from the overabundance of carbon chains in TMC-1, we find that L483 does not have a marked chemical differentiation with respect to starless/prestellar cores like TMC-1 and L1544, although it does chemically differentiate from Class 0 hot corino sources like IRAS 16293-2422. This fact suggests that the chemical composition of the ambient cloud of some Class 0 sources could be largely inherited from the dark cloud starless/prestellar phase. We explore the use of potential chemical evolutionary indicators, such as the HNCO/C_3_S, SO_2_/C_2_S, and CH_3_SH/C_2_S ratios, to trace the prestellar/protostellar transition. We also derived isotopic ratios for a variety of molecules, many of which show isotopic ratios close to the values for the local interstellar medium (remarkably all those involving ^34^S and ^33^S), while there are also several isotopic anomalies like an extreme depletion in ^13^C for one of the two isotopologs of c-C_3_H_2_, a drastic enrichment in ^18^O for SO and HNCO (SO being also largely enriched in ^17^O), and different abundances for the two ^13^C substituted species of C_2_H and the two ^15^N substituted species of N_2_H^+^. We report the first detection in space of some minor isotopologs and quantify for the first time the deuterium fractionation for HDCCO and c-C_3_D. The exhaustive chemical characterization of L483 presented here, together with similar studies of other prestellar and protostellar sources, should allow us to identify the main factors that regulate the chemical composition of cores along the process of formation of low-mass protostars.
885. Giant Gemini GMOS survey. I.
ID:
ivo://CDS.VizieR/J/MNRAS/445/1745
Title:
Giant Gemini GMOS survey. I.
Short Name:
J/MNRAS/445/1745
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectra of 163 quasars at z_em_>4.4 taken with the Gemini Multi Object Spectrometers, the largest publicly available sample of high-quality (signal-to-noise ratio S/N~20 per 1.85{AA} pixel) low-resolution (full width at half maximum FWHM~320km/s) rest-frame ultraviolet quasar spectra at these redshifts. The sample was selected from SDSS Data Release 7 with the aim to obtain high-S/N follow-up spectra of the intergalactic HI Lyman series and Lyman continuum absorption at high redshift. Each quasar was observed with the GMOS B600 (FWHM~320km/s) and R400 (FWHM~360km/s) gratings to cover the rest-frame wavelength range from ~850 to ~1500{AA}. Here we make the spectra available in reduced form. The accompanying paper presents a detailed description the sample and a measurement of the mean free path to Lyman limit photons in the IGM, based on stacked rest-frame quasar spectra.
886. Giant Radio Quasars properties
ID:
ivo://CDS.VizieR/J/MNRAS/426/851
Title:
Giant Radio Quasars properties
Short Name:
J/MNRAS/426/851
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analysed the optical and radio properties of lobe-dominated giant-sized (>0.72Mpc) radio quasars and compared the results with those derived for a sample of smaller radio sources to determine whether the large size of some extragalactic radio sources is related to the properties of their nuclei. We compiled the largest (to date) sample of giant radio quasars, including 24 new and 21 previously known objects, and calculated a number of important parameters of their nuclei such as the black hole mass and the accretion rate.
887. GJ 3998 RVs, S and Halpha indexes
ID:
ivo://CDS.VizieR/J/A+A/593/A117
Title:
GJ 3998 RVs, S and Halpha indexes
Short Name:
J/A+A/593/A117
Date:
21 Oct 2021
Publisher:
CDS
Description:
M dwarfs are considered ideal targets for Doppler radial velocity searches. Nonetheless, the statistics of frequency of low-mass planets hosted by low mass stars remains poorly constrained. Our M-dwarf radial velocity monitoring with HARPS-N can provide a major contribution to the widening of the current statistics through the in-depth analysis of accurate radial velocity observations in a narrow range of spectral sub-types (79 stars, between dM0 to dM3). Spectral accuracy will enable us to reach the precision needed to detect small planets with a few earth masses. Our survey will bring a contribute to the surveys devoted to the search for planets around M-dwarfs, mainly focused on the M-dwarf population of the northern hemisphere, for which we will provide an estimate of the planet occurence. We present here a long duration radial velocity monitoring of the M1 dwarf star GJ 3998 with HARPS-N to identify periodic signals in the data. Almost simultaneous photometric observations were carried out within the APACHE and EXORAP programs to characterize the stellar activity and to distinguish from the periodic signals those due to activity and to the presence of planetary companions. The radial velocities have a dispersion in excess of their internal errors due to at least four superimposed signals, with periods of 30.7, 13.7, 42.5 and 2.65-days. The analysis of spectral indices based on Ca II H & K and H{alpha} lines demonstrates that the periods of 30.7 and 42.5-days are due to chromospheric inhomogeneities modulated by stellar rotation and differential rotation. The shorter periods of 13.74+/-0.02d and 2.6498+/-0.0008d are well explained with the presence of two planets, with minimum masses of 6.26+/-0.79M_Earth_ and 2.47+/-0.27M_Earth_ and distances of 0.089AU and 0.029AU from the host, respectively.
888. GLASS. IV. Lensing cluster Abell 2744
ID:
ivo://CDS.VizieR/J/ApJ/811/29
Title:
GLASS. IV. Lensing cluster Abell 2744
Short Name:
J/ApJ/811/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a strong and weak lensing reconstruction of the massive cluster Abell 2744, the first cluster for which deep Hubble Frontier Fields (HFF) images and spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS) are available. By performing a targeted search for emission lines in multiply imaged sources using the GLASS spectra, we obtain five high-confidence spectroscopic redshifts and two tentative ones. We confirm one strongly lensed system by detecting the same emission lines in all three multiple images. We also search for additional line emitters blindly and use the full GLASS spectroscopic catalog to test reliability of photometric redshifts for faint line emitters. We see a reasonable agreement between our photometric and spectroscopic redshift measurements, when including nebular emission in photometric redshift estimations. We introduce a stringent procedure to identify only secure multiple image sets based on colors, morphology, and spectroscopy. By combining 7 multiple image systems with secure spectroscopic redshifts (at 5 distinct redshift planes) with 18 multiple image systems with secure photometric redshifts, we reconstruct the gravitational potential of the cluster pixellated on an adaptive grid, using a total of 72 images. The resulting mass map is compared with a stellar mass map obtained from the deep Spitzer Frontier Fields data to study the relative distribution of stars and dark matter in the cluster. We find that the stellar to total mass ratio varies substantially across the cluster field, suggesting that stars do not trace exactly the total mass in this interacting system. The maps of convergence, shear, and magnification are made available in the standard HFF format.
889. GLASS. IX. Structural param. from HFF & GLASS
ID:
ivo://CDS.VizieR/J/ApJ/835/254
Title:
GLASS. IX. Structural param. from HFF & GLASS
Short Name:
J/ApJ/835/254
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using deep Hubble Frontier Fields imaging and slitless spectroscopy from the Grism Survey from Space, we study 2200 cluster and 1748 field galaxies at 0.2<=z<=0.7 to determine the impact of environment on galaxy size and structure at stellar masses logM_*_/M_{sun}_>7.8, an unprecedented limit at these redshifts. Based on simple assumptions-r_e_=f(M_*_)-we find no significant differences in half-light radii (r_e_) between equal-mass cluster or field systems. More complex analyses --r_e_=f(M_*_,U-V,n,z,{Sigma})-- reveal local density ({Sigma}) to induce only a 7%+/-3% (95% confidence) reduction in r_e_ beyond what can be accounted for by U-V color, Sersic index (n), and redshift (z) effects. Almost any size difference between galaxies in high- and low-density regions is thus attributable to their different distributions in properties other than environment. Indeed, we find a clear color-r_e_ correlation in low-mass passive cluster galaxies (logM_*_/M_{sun}_<9.8) such that bluer systems have larger radii, with the bluest having sizes consistent with equal-mass star-forming galaxies. We take this as evidence that large-r_e_ low-mass passive cluster galaxies are recently acquired systems that have been environmentally quenched without significant structural transformation (e.g., by ram pressure stripping or starvation). Conversely, ~20% of small-r_e_ low-mass passive cluster galaxies appear to have been in place since z>~3. Given the consistency of the small-r_e_ galaxies' stellar surface densities (and even colors) with those of systems more than ten times as massive, our findings suggest that clusters mark places where galaxy evolution is accelerated for an ancient base population spanning most masses, with late-time additions quenched by environment-specific mechanisms mainly restricted to the lowest masses.
890. GLASS. VI. MCS J0416.1-2403 HFF imaging & spectra
ID:
ivo://CDS.VizieR/J/ApJ/831/182
Title:
GLASS. VI. MCS J0416.1-2403 HFF imaging & spectra
Short Name:
J/ApJ/831/182
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a model using both strong and weak gravitational lensing of the galaxy cluster MACS J0416.1-2403, constrained using spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS) and Hubble Frontier Fields (HFF) imaging data. We search for emission lines in known multiply imaged sources in the GLASS spectra, obtaining secure spectroscopic redshifts of 30 multiple images belonging to 15 distinct source galaxies. The GLASS spectra provide the first spectroscopic measurements for five of the source galaxies. The weak lensing signal is acquired from 884 galaxies in the F606W HFF image. By combining the weak lensing constraints with 15 multiple image systems with spectroscopic redshifts and nine multiple image systems with photometric redshifts, we reconstruct the gravitational potential of the cluster on an adaptive grid. The resulting map of total mass density is compared with a map of stellar mass density obtained from the deep Spitzer Frontier Fields imaging data to study the relative distribution of stellar and total mass in the cluster. We find that the projected stellar mass to total mass ratio, f*, varies considerably with the stellar surface mass density. The mean projected stellar mass to total mass ratio is <f*>=0.009+/-0.003 (stat.), but with a systematic error as large as 0.004-0.005, dominated by the choice of the initial mass function. We find agreement with several recent measurements of f* in massive cluster environments. The lensing maps of convergence, shear, and magnification are made available to the broader community in the standard HFF format.

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