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- ID:
- ivo://CDS.VizieR/J/A+A/478/83
- Title:
- GOODS-South Field VLT/FORS2 redshifts. III.
- Short Name:
- J/A+A/478/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third results (including the previous two releases) of the ESO/GOODS program of spectroscopy of faint galaxies in the Chandra Deep Field South (CDF-S). The typical redshift uncertainty is estimated to be {sigma}z~0.001. The reduced spectra and the derived redshifts are released to the community through the ESO web page http://www.eso.org/science/goods/
- ID:
- ivo://CDS.VizieR/J/AJ/131/49
- Title:
- Gravitational lenses among z>=4.0 quasars
- Short Name:
- J/AJ/131/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on i-band snapshot observations of 157 Sloan Digital Sky Survey quasars at 4.0<z<5.4 using the Advanced Camera for Surveys on the Hubble Space Telescope (HST) to search for evidence of gravitational lensing of these sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/600/L155
- Title:
- Gravitational lens in GOODS ACS fields
- Short Name:
- J/ApJ/600/L155
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a systematic search for strong gravitational lenses in the Great Observatories Origins Deep Survey (GOODS) Advanced Camera for Surveys (ACS) data. The search technique involves creating a sample of likely lensing galaxies, which we define as massive early-type galaxies in a redshift range 0.3<z<1.3. The target galaxies are selected by color and magnitude, giving a sample of 1092 galaxies. For each galaxy in the sample, we subtract a smooth description of the galaxy light from the z850-band data. The residuals are examined, along with true-color images created from the B_435_V_606_i_775_ data, for morphologies indicative of strong lensing. We present our six most promising lens candidates as well as our full list of candidates.
- ID:
- ivo://CDS.VizieR/J/MNRAS/421/1874
- Title:
- GRB 100901A and GRB 100906A light curves
- Short Name:
- J/MNRAS/421/1874
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the prompt, early and afterglow optical observations of five {gamma}-ray bursts (GRBs): GRB 100901A, GRB 100902A, GRB 100905A, GRB 100906A and GRB 101020A. These observations were made with the Mobile Astronomical System of TElescope-Robots in Russia (MASTER-II Net), the 1.5-m telescope of the Sierra Nevada Observatory and the 2.56-m Nordic Optical Telescope.
- ID:
- ivo://CDS.VizieR/J/ApJ/778/128
- Title:
- GRB-host galaxies photometry
- Short Name:
- J/ApJ/778/128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations and analysis of the host galaxies of 23 heavily dust-obscured gamma-ray bursts (GRBs) observed by the Swift satellite during the years 2005-2009, representing all GRBs with an unambiguous host-frame extinction of A_V_>1mag from this period. Deep observations with Keck, Gemini, Very Large Telescope, Hubble Space Telescope, and Spitzer successfully detect the host galaxies and establish spectroscopic or photometric redshifts for all 23 events, enabling us to provide measurements of the intrinsic host star formation rates, stellar masses, and mean extinctions. Compared to the hosts of unobscured GRBs at similar redshifts, we find that the hosts of dust-obscured GRBs are (on average) more massive by about an order of magnitude and also more rapidly star forming and dust obscured. While this demonstrates that GRBs populate all types of star-forming galaxies, including the most massive, luminous systems at z{approx}2, at redshifts below 1.5 the overall GRB population continues to show a highly significant aversion to massive galaxies and a preference for low-mass systems relative to what would be expected given a purely star-formation-rate-selected galaxy sample. This supports the notion that the GRB rate is strongly dependent on metallicity, and may suggest that the most massive galaxies in the universe underwent a transition in their chemical properties ~9Gyr ago. We also conclude that, based on the absence of unobscured GRBs in massive galaxies and the absence of obscured GRBs in low-mass galaxies, the dust distributions of the lowest-mass and the highest-mass galaxies are relatively homogeneous, while intermediate-mass galaxies (~10^9^M_{sun}_) have diverse internal properties.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/73
- Title:
- GRB with early-time optical emission
- Short Name:
- J/ApJ/772/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multi-wavelength analysis of Swift gamma-ray burst GRB 090727, for which optical emission was detected during the prompt {gamma}-ray emission by the 2m autonomous robotic Liverpool Telescope and subsequently monitored for a further two days with the Liverpool and Faulkes Telescopes. Within the context of the standard fireball model, we rule out a reverse shock origin for the early-time optical emission in GRB 090727 and instead conclude that the early-time optical flash likely corresponds to emission from an internal dissipation process. Putting GRB 090727 into a broader observational and theoretical context, we build a sample of 36 {gamma}-ray bursts (GRBs) with contemporaneous early-time optical and {gamma}-ray detections. From these GRBs, we extract a sub-sample of 18 GRBs, which show optical peaks during prompt {gamma}-ray emission, and perform detailed temporal and spectral analysis in {gamma}-ray, X-ray, and optical bands. We find that in most cases early-time optical emission shows sharp and steep behavior, and notice a rich diversity of spectral properties. Using a simple internal shock dissipation model, we show that the emission during prompt GRB phase can occur at very different frequencies via synchrotron radiation. Based on the results obtained from observations and simulation, we conclude that the standard external shock interpretation for early-time optical emission is disfavored in most cases due to sharp peaks ({Delta}t/t<1) and steep rise/decay indices, and that internal dissipation can explain the properties of GRBs with optical peaks during {gamma}-ray emission.
- ID:
- ivo://CDS.VizieR/J/A+A/536/A89
- Title:
- g'r'i' and redshift of Abell 2254 galaxies
- Short Name:
- J/A+A/536/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The mechanisms giving rise to diffuse radio emission in galaxy clusters and, in particular, their connection with cluster mergers are still being debated. We explore the internal dynamics of Abell 2254, which has been shown to host a very clumpy and irregular radio halo. Our analysis is mainly based on redshift data for 128 galaxies acquired at the Telescopio Nazionale Galileo. We combined galaxy velocities and positions to select 110 cluster galaxies and analyze its internal dynamics. We also used new (g', r', i') photometric data acquired at the Isaac Newton Telescope, and (V, i') photometric data available in the Subaru Archive. X-ray data from the XMM-Newton Science Archive were analyzed to study the hot gas component.
1729. griBVI photometry in M37
- ID:
- ivo://CDS.VizieR/J/ApJ/691/342
- Title:
- griBVI photometry in M37
- Short Name:
- J/ApJ/691/342
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the course of conducting a deep (14.5<~r<~23), 20 night survey for transiting planets in the rich ~550Myr old open cluster M37, we have measured the rotation periods of 575 stars, which lie near the cluster main sequence, with masses 0.2M_{sun}_<~M<~1.3M_{sun}_. This is the largest sample of rotation periods for a cluster older than 500Myr. Using this rich sample we investigate a number of relations between rotation period, color, and the amplitude of photometric variability.
- ID:
- ivo://CDS.VizieR/J/AJ/160/277
- Title:
- gri-light curve of near-Earth asteroid 2020 CD3
- Short Name:
- J/AJ/160/277
- Date:
- 08 Dec 2021
- Publisher:
- CDS
- Description:
- We report on our detailed characterization of Earth's second known temporary natural satellite, or minimoon, asteroid 2020CD3. An artificial origin can be ruled out based on its area-to-mass ratio and broadband photometry, which suggest that it is a silicate asteroid belonging to the S or V complex in asteroid taxonomy. The discovery of 2020CD3 allows for the first time a comparison between known minimoons and theoretical models of their expected physical and dynamical properties. The estimated diameter of 1.2_-0.2_^+0.4^m and geocentric capture approximately a decade after the first known minimoon, 2006RH120, are in agreement with theoretical predictions. The capture duration of 2020CD3 of at least 2.7yr is unexpectedly long compared to the simulation average, but it is in agreement with simulated minimoons that have close lunar encounters, providing additional support for the orbital models. 2020CD3's atypical rotation period, significantly longer than theoretical predictions, suggests that our understanding of meter-scale asteroids needs revision. More discoveries and a detailed characterization of the population can be expected with the forthcoming Vera C. Rubin Observatory Legacy Survey of Space and Time.
