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451. ACO 370, 2218 and 2390 fluxes at 7 and 15um
ID:
ivo://CDS.VizieR/J/A+A/407/791
Title:
ACO 370, 2218 and 2390 fluxes at 7 and 15um
Short Name:
J/A+A/407/791
Date:
21 Oct 2021
Publisher:
CDS
Description:
ESA's Infrared Space Observatory (ISO) was used to perform a deep survey with ISOCAM through three massive gravitationally lensing clusters of galaxies. The total area surveyed depends on source flux, with nearly seventy square arcminutes covered for the brighter flux levels in maps centred on the three clusters Abell 370, Abell 2218 and Abell 2390. We present maps and photometry at 6.7um (hereafter 7um) and 14.3um (hereafter 15um), showing a total of 145 mid-infrared sources and the associated source counts.
452. A1367, Coma and Virgo r' photometry
ID:
ivo://CDS.VizieR/J/A+A/401/471
Title:
A1367, Coma and Virgo r' photometry
Short Name:
J/A+A/401/471
Date:
21 Oct 2021
Publisher:
CDS
Description:
Optical spectroscopy of 93 galaxies, 60 projected in the direction of Abell 1367, 21 onto the Coma cluster and 12 on Virgo, is reported. The targets were selected because they were detected in previous H{alpha}, UV or r' surveys. The present observations bring to 100% the redshift completeness of H{alpha} selected galaxies in the Coma region and to 75% in Abell 1367. All observed galaxies except one show H{alpha} emission and belong to the clusters. This confirms previous determinations of the H{alpha} luminosity function of the two clusters that were based on the assumption that all H{alpha} detected galaxies were cluster members. Using the newly obtained data we re-determine the UV luminosity function of Coma and we compute for the first time the UV luminosity function of A1367.
453. A combined Chandra & LAMOST study of stellar activity
ID:
ivo://CDS.VizieR/J/ApJ/871/193
Title:
A combined Chandra & LAMOST study of stellar activity
Short Name:
J/ApJ/871/193
Date:
21 Oct 2021
Publisher:
CDS
Description:
We probed stellar X-ray activity over a wide range of stellar parameters, using Chandra and Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) data. We measured the X-ray-to-bolometric luminosity ratio (R_X_=L_X_/L_bol_) for 484 main-sequence stars and found a bimodal distribution for G and K types. We interpret this bimodality as evidence of two subpopulations with different coronal temperatures, which are caused by different coronal heating rates. Using the metallicity and velocity information, we find that both of the subpopulations are mostly located in the thin disk. We find no trend of R_X_ with stellar age for stars older than ~4Gyr; there is a trough in the R_X_ versus age distribution, with the lowest range of R_X_ appearing at ages around 2Gyr. We then examined the correlation between R_X_ and R_H{alpha}_ (proxy of chromospheric activity): we find that the two quantities are well correlated, as found in many earlier studies. Finally, we selected a sample of 12 stars with X-ray flares and studied the light-curve morphology of the flares. The variety of flare profiles and timescales observed in our sample suggests the contribution of different processes of energy release.
454. A comparison of centering in ISS astrometry
ID:
ivo://CDS.VizieR/J/MNRAS/505/5253
Title:
A comparison of centering in ISS astrometry
Short Name:
J/MNRAS/505/5253
Date:
22 Feb 2022
Publisher:
CDS
Description:
In the caviar software package, a standard tool for astrometry of images from the Cassini imaging science subsystem (ISS), Gaussian fitting is used to measure the centre of point-like objects, achieving a typical precision of about 0.2 pixels. In this work, we consider how alternative methods may improve on this. We compare three traditional centroiding methods: two-dimensional Gaussian fitting, median, and modified moment. Results using 56 selected images show that the centroiding precision of the modified moment method is significantly better than the other two methods, with standard deviations for all residuals in sample and line of 0.065 and 0.063 pixels, respectively, representing a factor of over 2 improvement compared to Gaussian fitting. Secondly, a comparison of observations using Cassini ISS images of Anthe is performed. Anthe results show a similar improvement. The modified moment method is then used to reduce all ISS images of Anthe during the period 2008-2017. The observed-minus-calculated residuals relative to the JPL SAT393 ephemeris are calculated. In terms of {alpha}xcos({delta}) and {delta} in the Cassini-centred international celestial reference frame, mean values of all residuals are close to 0km, and their standard deviations are less than 1km for narrow angle camera images, and about 4km for wide angle camera images.
455. A compilation of 128 galaxy-galaxy strong-lens systems
ID:
ivo://CDS.VizieR/J/ApJ/864/91
Title:
A compilation of 128 galaxy-galaxy strong-lens systems
Short Name:
J/ApJ/864/91
Date:
03 Nov 2021 13:33:10
Publisher:
CDS
Description:
We propose a new strategy of finding strongly lensed supernovae (SNe) by monitoring known galaxy-scale strong-lens systems. Strongly lensed SNe are potentially powerful tools for the study of cosmology, galaxy evolution, and stellar populations, but they are extremely rare. By targeting known strongly lensed star-forming galaxies, our strategy significantly boosts the detection efficiency for lensed SNe compared to a blind search. As a reference sample, we compile the 128 galaxy-galaxy strong-lens systems from the Sloan Lens ACS Survey (SLACS), the SLACS for the Masses Survey, and the Baryon Oscillation Spectroscopic Survey Emission-Line Lens Survey. Within this sample, we estimate the rates of strongly lensed Type Ia SN (SNIa) and core-collapse SN (CCSN) to be 1.23+/-0.12 and 10.4+/-1.1 events per year, respectively. The lensed SN images are expected to be widely separated with a median separation of 2". Assuming a conservative fiducial lensing magnification factor of 5 for the most highly magnified SN image, we forecast that a monitoring program with a single-visit depth of 24.7mag (5{sigma} point source, r band) and a cadence of 5days can detect 0.49 strongly lensed SNIa event and 2.1 strongly lensed CCSN events per year within this sample. Our proposed targeted-search strategy is particularly useful for prompt and efficient identifications and follow-up observations of strongly lensed SN candidates. It also allows telescopes with small fields of view and limited time to efficiently discover strongly lensed SNe with a pencil-beam scanning strategy.
456. A compilation of interstellar column densities
ID:
ivo://CDS.VizieR/J/ApJS/199/8
Title:
A compilation of interstellar column densities
Short Name:
J/ApJS/199/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have collated absorption line data toward 3008 stars in order to create a unified database of interstellar column densities. These data have been taken from a number of different published sources and include many different species and ionizations. The preliminary results from our analysis show a tight relation [N(H)/E(B-V)=6.12x10^21^] between N(H) and E(B-V). Similar plots have been obtained with many different species, and their correlations along with the correlation coefficients are presented.
457. A complete sample of broad-line AGN from SDSS-DR7
ID:
ivo://CDS.VizieR/J/ApJS/243/21
Title:
A complete sample of broad-line AGN from SDSS-DR7
Short Name:
J/ApJS/243/21
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new, complete sample of 14584 broad-line active galactic nuclei (AGNs) at z<0.35 is presented, which are uncovered homogeneously from the complete database of galaxies and quasars observed spectroscopically in the Sloan Digital Sky Survey Seventh Data Release. The stellar continuum is properly removed for each spectrum with significant host absorption line features, and careful analyses of the emission line spectra, particularly in the H{alpha} and H{beta} wavebands, are carried out. The broad Balmer emission line, particularly H{alpha}, is used to indicate the presence of an AGN. The broad H{alpha} lines have luminosities in a range of 10^38.5^-10^44.3^erg/s, and line widths (FWHMs) of 500-34000km/s. The virial black hole masses, estimated from the broad-line measurements, span a range of 10^5.1^-10^10.3^M_{sun}_, and the Eddington ratios vary from -3.3 to 1.3 in logarithmic scale. Other quantities such as multiwavelength photometric properties and flags denoting peculiar line profiles are also included in this catalog. We describe the construction of this catalog and briefly discuss its properties. The catalog is publicly available online. This homogeneously selected AGN catalog, along with the accurately measured spectral parameters, provides the most updated, largest AGN sample data, which will enable further comprehensive investigations of the properties of the AGN population in the low-redshift universe.
458. A3558 complex redshifts
ID:
ivo://CDS.VizieR/J/MNRAS/296/599
Title:
A3558 complex redshifts
Short Name:
J/MNRAS/296/599
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Shapley Concentration is the richest supercluster of clusters in the nearby Universe, and its core is a remarkable complex formed by the ACO clusters A3558, A3562 and A3556, and by the two minor groups SC 1327-312 and SC 1329-314. This structure has been studied in various wavelength bands, revealing that it is probably dynamically very active. In this paper we present 174 new galaxy redshifts in this cluster complex, which are added to the sample of 540 already existing velocities. The spectroscopic observations were performed at the 3.6m ESO telescope at La Silla, equiped with the OPTOPUS multifibre spectrograph, on the nights 1993 February of 21-24.
459. A composite HII region luminosity function
ID:
ivo://CDS.VizieR/J/A+A/459/L13
Title:
A composite HII region luminosity function
Short Name:
J/A+A/459/L13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Statistical properties of HII region populations in disk galaxies yield important clues to the physics of massive star formation. We present a set of HII region catalogues and luminosity functions for a sample of 56 spiral galaxies in order to derive the most general form of their luminosity function. HII region luminosity functions were derived for individual galaxies which, after photometric calibration, were summed to form a total luminosity function comprising 17797 HII regions from 53 galaxies.
460. A comprehensive analysis of Spitzer supernovae
ID:
ivo://CDS.VizieR/J/ApJS/241/38
Title:
A comprehensive analysis of Spitzer supernovae
Short Name:
J/ApJS/241/38
Date:
21 Oct 2021
Publisher:
CDS
Description:
The mid-infrared (mid-IR) wavelength regime offers several advantages for following the late-time evolution of supernovae (SNe). First, the peaks of the SN spectral energy distributions shift toward longer wavelengths, following the photospheric phase. Second, mid-IR observations suffer less from effects of interstellar extinction. Third, and perhaps most important, the mid-IR traces dust formation and circumstellar interaction at late times (>100 days) after the radioactive ejecta component fades. The Spitzer Space Telescope has provided substantial mid-IR observations of SNe since its launch in 2003. More than 200 SNe have been targeted, but there are even more SNe that have been observed serendipitously. Here we present the results of a comprehensive study based on archival Spitzer/IRAC images of more than 1100 SN positions; from this sample, 119 SNe of various subclasses have been detected, including 45 SNe with previously unpublished mid-IR photometry. The photometry reveals significant amounts of warm dust in some cases. We perform an in-depth analysis to constrain the origin and heating mechanism of the dust, and present the resulting statistics.

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