- ID:
- ivo://CDS.VizieR/J/AcA/68/351
- Title:
- Predicted Microlensing Events by nearby VLM objects
- Short Name:
- J/AcA/68/351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Microlensing events can be used to directly measure the masses of single field stars to a precision of ~1-10%. The majority of direct mass measurements for stellar and sub-stellar objects typically only come from observations of binary systems. Hence microlensing provides an important channel for direct mass measurements of single stars. The Gaia satellite has observed ~1.7 billion objects, and analysis of the second data release has recently yielded numerous event predictions for the next few decades. However, the Gaia catalog is incomplete for nearby very-low-mass objects such as brown dwarfs for which mass measurements are most crucial. We employ a catalog of very-low-mass objects from Pan-STARRS data release 1 (PDR1) as potential lens stars, and we use the objects from Gaia data release 2 (GDR2) as potential source stars. We then search for future microlensing events up to the year 2070. The Pan-STARRS1 objects are first cross-matched with GDR2 to remove any that are present in both catalogs. This leaves a sample of 1718 possible lenses. We fit MIST isochrones to the Pan-STARRS1, AllWISE and 2MASS photometry to estimate their masses. We then compute their paths on the sky, along with the paths of the GDR2 source objects, until the year 2070, and search for potential microlensing events. Source-lens pairs that will produce a microlensing signal with an astrometric amplitude of greater than 0.131mas, or a photometric amplitude of greater than 0.4mmag, are retained.
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- ID:
- ivo://CDS.VizieR/J/AcA/68/183
- Title:
- Predicted Microlensing Events for the 21st Century
- Short Name:
- J/AcA/68/183
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using Gaia data release 2 (GDR2, Cat. I/345), we present an almanac of 2509 predicted microlensing events, caused by 2130 unique lens stars, that will peak between July 25, 2026 and the end of the century. This work extends and completes a thorough search for future microlensing events initiated by Bramich and Nielsen using GDR2. The almanac includes 161 lenses that will cause at least two microlensing events each. All of the predicted microlensing events in the almanac will exhibit astrometric signals that are detectable by observing facilities with an angular resolution and astrometric precision similar to, or better than, that of the Hubble Space Telescope (e.g., NIRCam on the James Webb Space Telescope), although the events with the most extreme source-to-lens contrast ratios may be challenging. Ground-based telescopes of at least 1 m in diameter can be used to observe many of the events that are also expected to exhibit a photometric signal.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A44
- Title:
- Predicted microlensing events from Gaia DR2
- Short Name:
- J/A+A/618/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- I search for source-lens pairs in Gaia Data Release 2 (GDR2, Cat. I/345) that could potentially lead to microlensing events between 25th July 2014 and 25th July 2026. I estimate the lens masses using GDR2 photometry and parallaxes, and appropriate model stellar isochrones. Combined with the source and lens parallax measurements from GDR2, this allows the Einstein ring radius to be computed for each source-lens pair. By considering the source and lens paths on the sky, I calculate the microlensing signals that are to be expected.
- ID:
- ivo://CDS.VizieR/J/ApJ/817/85
- Title:
- Properties of giant arcs behind CLASH clusters
- Short Name:
- J/ApJ/817/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We developed an algorithm to find and characterize gravitationally lensed galaxies (arcs) to perform a comparison of the observed and simulated arc abundance. Observations are from the Cluster Lensing And Supernova survey with Hubble (CLASH). Simulated CLASH images are created using the MOKA package and also clusters selected from the high-resolution, hydrodynamical simulations, MUSIC, over the same mass and redshift range as the CLASH sample. The algorithm's arc elongation accuracy, completeness, and false positive rate are determined and used to compute an estimate of the true arc abundance. We derive a lensing efficiency of 4+/-1 arcs (with length >=6" and length-to-width ratio >=7) per cluster for the X-ray-selected CLASH sample, 4+/-1 arcs per cluster for the MOKA-simulated sample, and 3+/-1 arcs per cluster for the MUSIC-simulated sample. The observed and simulated arc statistics are in full agreement. We measure the photometric redshifts of all detected arcs and find a median redshift z_s_=1.9 with 33% of the detected arcs having z_s_>3. We find that the arc abundance does not depend strongly on the source redshift distribution but is sensitive to the mass distribution of the dark matter halos (e.g., the c-M relation). Our results show that consistency between the observed and simulated distributions of lensed arc sizes and axial ratios can be achieved by using cluster-lensing simulations that are carefully matched to the selection criteria used in the observations.
- ID:
- ivo://CDS.VizieR/J/ApJ/797/138
- Title:
- Properties of SMG lens candidates
- Short Name:
- J/ApJ/797/138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Keck-Adaptive Optics and Hubble Space Telescope high resolution near-infrared (IR) imaging for 500{mu}m bright candidate lensing systems identified by the Herschel Multi-tiered Extragalactic Survey and Herschel Astrophysical Terahertz Large Area Survey. Out of 87 candidates with near-IR imaging, 15 (~17%) display clear near-IR lensing morphologies. We present near-IR lens models to reconstruct and recover basic rest-frame optical morphological properties of the background galaxies from 12 new systems. Sources with the largest near-IR magnification factors also tend to be the most compact, consistent with the size bias predicted from simulations and previous lensing models for submillimeter galaxies (SMGs). The rest-frame optical properties of our sample of Herschel-selected lensed SMGs are consistent with those of unlensed SMGs, which suggests that the two populations are similar.
- ID:
- ivo://CDS.VizieR/VII/248
- Title:
- Quasars and Active Galactic Nuclei (12th Ed.)
- Short Name:
- VII/248
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is an update of the previous versions; as in the previous editions no information about absorption lines of X-ray properties are given, but absolute magnitudes are given, assuming Ho=50km/s/Mpc and q_0_=0. In this edition the 20cm radio flux is listed when available, in place of the 11cm flux. The present edition of this catalogue contains the quasars with measured redshift known prior to January 1st, 2006. It contains 85221 quasars, 1122 BL Lac objects and 21737 active galaxies (including 9628 Seyfert 1s), almost doubling the number listed in the 11th edition. Lists of known lensed quasars (table2.dat) and double quasars (table3.dat) are also given here.
- ID:
- ivo://CDS.VizieR/VII/258
- Title:
- Quasars and Active Galactic Nuclei (13th Ed.)
- Short Name:
- VII/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is a compilation of all known AGNs presented in a compact and convenient form. It is an update of the previous versions; and as in the previous editions no information about absorption lines of X-ray properties are given, but absolute magnitudes are given, assuming Ho=71km/s/Mpc and q_0_=0 (notice the change of cosmology: Ho was assumed to be 50km/s/Mpc in the previous editions). When available, the 20cm and 6cm radio flux are given. The present edition of this catalogue contains the quasars with measured redshift known prior to July 1st, 2009. It contains 133336 quasars, 1374 BL Lac objects and 34231 active galaxies (including 15627 Seyfert 1's), almost doubling the number listed in the 12th edition. Lists of known lensed quasars (table2.dat) and double quasars (table3.dat) are also given here.
- ID:
- ivo://CDS.VizieR/J/ApJ/896/70
- Title:
- Radial acceleration relation in CLASH galaxy clusters
- Short Name:
- J/ApJ/896/70
- Date:
- 03 Dec 2021 13:12:15
- Publisher:
- CDS
- Description:
- The radial acceleration relation (RAR) in galaxies describes a tight empirical scaling law between the total acceleration g_tot_(r)=GM_tot_(<r)/r^2^ observed in galaxies and that expected from their baryonic mass g_bar_(r)=GM_bar_(<r)/r^2^, with a characteristic acceleration scale of g_{dagger}_~1.2x10^-10^m/s^2^. Here, we examine if such a correlation exists in galaxy clusters using weak-lensing, strong-lensing, and X-ray data sets available for 20 high-mass clusters targeted by the Cluster Lensing And Supernova survey with Hubble (CLASH). By combining our CLASH data with stellar mass estimates for the brightest cluster galaxies (BCGs) and accounting for the stellar baryonic component in clusters, we determine, for the first time, an RAR on BCG-cluster scales. The resulting RAR is well described by a tight power-law relation, g_tot_{propto}g_bar_^0.51-0.05+0.04^, with lognormal intrinsic scatter of 14.7_-2.8_^+2.9^%. The slope is consistent with the low acceleration limit of the RAR in galaxies, g_tot_=(g_{dagger}_,g_bar_)^0.5^, whereas the intercept implies a much higher acceleration scale of g_{dagger}_=(2.02+/-0.11)x10^-9^m/s^2^, indicating that there is no universal RAR that holds on all scales from galaxies to clusters. We find that the observed RAR in CLASH clusters is consistent with predictions from a semianalytical model developed in the standard {Lambda}CDM framework. Our results also predict the presence of a baryonic Faber-Jackson relation ({sigma}_v^4^{propto}M_bar_) on cluster scales.
- ID:
- ivo://CDS.VizieR/J/A+A/640/A105
- Title:
- R-band light curves of 23 lensed QSOs
- Short Name:
- J/A+A/640/A105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of 15 years of monitoring lensed quasars, which was conducted by the COSMOGRAIL programme at the Leonhard Euler 1.2m Swiss Telescope. The decade-long light curves of 23 lensed systems are presented for the first time. We complement our data set with other monitoring data available in the literature to measure the time delays in 18 systems, among which nine reach a relative precision better than 15% for at least one time delay. To achieve this, we developed an automated version of the curve-shifting toolbox PyCS to ensure robust estimation of the time delay in the presence of microlensing, while accounting for the errors due to the imperfect representation of microlensing. We also re-analysed the previously published time delays of RXj1131-1231 and HE0435-1223, by adding six and two new seasons of monitoring, respectively, and confirming the previous time-delay measurements. When the time delay measurement is possible, we corrected the light curves of the lensed images from their time delay and present the difference curves to highlight the microlensing signal contained in the data. To date, this is the largest sample of decade-long lens monitoring data, which is useful to measure $H_0$ and the size of quasar accretion discs with microlensing as well as to study quasar variability.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A193
- Title:
- Rc-band light curves of 6 lensed QSOs
- Short Name:
- J/A+A/642/A193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present six new time-delay measurements obtained from Rc-band monitoring data acquired at the MPIA 2.2m telescope at La Silla observatory between October 2016 and February 2020. The lensed quasars HE 0047-1756, WG 0214-2105, DES 0407-5006, 2M 1134-2103, PSJ 1606-2333 and DES 2325-5229 were observed almost daily at high signal-to-noise ratio to obtain high-quality light curves where we can record fast and small-amplitude variations of the quasars. We measure time delays between all pairs of multiple images with only one or two seasons of monitoring at the exception of the time delays relative to image D of PSJ 1606-2333. The most precise estimate is obtained for the delay between image A and image B of DES 0407-5006, with {tau}_AB_=-128.4^+3.5^_-3.8_ days (2.8% precision) including systematics due to extrinsic variability in the light curves. For HE 0047-1756, we combine our high-cadence data with measurements from decade-long light-curves from previous COSMOGRAIL campaigns, and reach a precision of 0.9 day on the final measurement. The present work demonstrates the feasibility of measuring time delays in lensed quasars in only one or two seasons, provided high signal-to-noise ratio data are obtained at a cadence close to daily.
