- ID:
- ivo://CDS.VizieR/J/ApJ/887/268
- Title:
- Bright QSOs in Southern Hemisphere (QUBRICS)
- Short Name:
- J/ApJ/887/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of absorptions along the lines of sight to bright high-z QSOs is an invaluable cosmological tool that provides a wealth of information on the inter-/circum-galactic medium, dark matter, primordial elements, reionization, fundamental constants, and general relativity. Unfortunately, the number of bright (i<~18) QSOs at z>~2 in the southern hemisphere is much lower than that in the north, due to the lack of wide multiwavelength surveys at decl. {delta}<0{deg}, hampering the effectiveness of observations from southern observatories. In this work we present a new method based on Canonical Correlation Analysis to identify such objects, taking advantage of a number of available databases: Skymapper, Gaia DR2, WISE, and 2MASS. Our QSO candidate sample lists 1476 sources with i<18 over 12400deg^2^ in the southern hemisphere. With a preliminary campaign we observed spectroscopically 69 of them, confirming 54 new bright QSOs at z>2.5, corresponding to a success rate of our method of ~80%. Furthermore, we estimate a completeness of ~90% of our sample at completion of our observation campaign. The new QSOs confirmed by this first and the forthcoming campaigns (QUBRICS survey) will be the targets of subsequent studies using higher resolution spectrographs, like ESPRESSO, UVES, and (in the long term) ELT/HIRES.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/204/151
- Title:
- Bright radio sources at 178 MHz (3CRR)
- Short Name:
- J/MNRAS/204/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A revised sample of bright radio sources at 178MHz is defined in order to correct the biases introduced into the 3CR catalog by confusion and partial resolution. The sample is shown to be 96 percent complete to a flux-density limit of 10Jy for sources smaller than 10arcmin. The bias of the 3CR catalog against objects of larger angular size is also reduced. Optical identifications are presented for 96 percent of the sources, 71 percent with galaxies and 25 percent with quasars. The radio-galaxy population is found to show strong space-density evolution for luminosities in excess of approximately 10^26.5^W/Hz/sr at 178MHz (redshifts greater than or approximately equal to 0.2), while the evolutionary properties of galaxies and quasars of the same luminosity and redshift are very similar.
- ID:
- ivo://CDS.VizieR/J/AJ/135/1567
- Title:
- Bright star clusters in M51
- Short Name:
- J/AJ/135/1567
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of star clusters with V_F555W_<23mag detected in the interacting spiral galaxy M51 system based on mosaic images taken with the Hubble Space Telescope Advanced Camera for Surveys by the Hubble Heritage Team. We have selected about 3600 clusters based on their morphological information through visual inspection. The final star cluster catalog includes 2224 clusters that are relatively well isolated and have a circular shape.
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/4173
- Title:
- Bright white dwarfs for high-speed photometry
- Short Name:
- J/MNRAS/472/4173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The upcoming NASA Transiting Exoplanet Survey Satellite (TESS) will obtain space-based uninterrupted light curves for a large sample of bright white dwarfs distributed across the entire sky, providing a very rich resource for asteroseismological studies and the search for transits from planetary debris. We have compiled an all-sky catalogue of ultraviolet, optical and infrared photometry as well as proper motions, which we propose as an essential tool for the preliminary identification and characterization of potential targets. We present data for 1864 known white dwarfs and 305 high-probability white dwarf candidates brighter than 17mag. We describe the spectroscopic follow-up of 135 stars, of which 82 are white dwarfs and 25 are hot subdwarfs. The new confirmed stars include six pulsating white dwarf candidates (ZZ Cetis), and nine white dwarf binaries with a cool main- sequence companion. We identify one star with a spectroscopic distance of only 25pc from the Sun. Around the time TESS is launched, we foresee that all white dwarfs in this sample will have trigonometric parallaxes measured by the ESA Gaia mission next year.
- ID:
- ivo://CDS.VizieR/J/MNRAS/459/1415
- Title:
- Bright white dwarfs IRAC photometry
- Short Name:
- J/MNRAS/459/1415
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We cross-correlate several sources of archival photometry for 1265 bright (V~16mag) white dwarfs (WDs) with available high signal-to-noise spectroscopy. We find 381 WDs with archival Spitzer+IRAC data and investigate this subsample for infrared excesses due to circumstellar dust. This large data set reveals 15 dusty WDs, including three new debris discs and the hottest WD known to host dust (WD 0010+280). We study the frequency of debris discs at WDs as function of mass. The frequency peaks at 12.5 per cent for 0.7-0.75M_{sun}_ WDs (with 3M_{sun}_ main-sequence star progenitors) and falls off for stars more massive than this, which mirrors predicted planet occurrence rates for stars of different masses.
- ID:
- ivo://CDS.VizieR/J/AJ/149/111
- Title:
- BRI light curves of 2MASS J02272637+1156494
- Short Name:
- J/AJ/149/111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The star 1SWASP J022727.03+115641.7 was reported as a contact binary with a period shorter than the empirical limit of such systems. Our study shows the star not to be variable. Instead, it is the nearby star, 2MASS 02272637+1156494, that exhibits variability. The BRI CCD light curves of 2MASS 02272637+1156494 show the system to be a moderate mass ratio (2.154_-0.074_^+0.008^), and shallow contact (10.4_-1.9_^+1.4^%) W-type contact binary. The masses, radii, and luminosities of the binary components are, respectively, M_1_=0.25_-0.01_^+0.05^M_{sun}_, M_2_=0.54_-0.04_^+0.11^M_{sun}_, R_1_=0.45_-0.01_^+0.02^R_{sun}_, R_2_=0.63_-0.02_^+0.04^R_{sun}_, L_1_=0.038_-0.005_^+0.018^L_{sun}_, and L_2_=0.071_-0.010_^+0.037^L_{sun}_, with an estimated distance 326_-46_^+127^ pc. These uncertainties mainly come from the errors of the colors used to estimate the temperature of the primary star. A dark spot was introduced on the massive component in the final solution.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/17
- Title:
- BRI observations of the QSO Zw III 2
- Short Name:
- J/ApJS/226/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- III Zw 2 is the prototype of radio-intermediate quasars. Although there is the evidence of possessing strong jet, significant {gamma}-ray emission has not been reported before. In this work, we carry out a detailed analysis of the latest Fermi-LAT Pass 8 data. No significant {gamma}-ray signal has been detected in the time-averaged 7-year Fermi-LAT data of III Zw 2; however, we have identified two distinct {gamma}-ray flares with isotropic luminosities of ~10^45^erg/s. Multiwavelength data analysis (also including the optical photometric observations from Yunnan Observatories) are presented and the main finding is simultaneous optical and {gamma}-ray flares of III Zw 2 appearing in 2009 November. Violent {gamma}-ray variability with a doubling timescale of 2.5hr was detected in another {gamma}-ray flare in May 2010, for which the 3-hr {gamma}-ray peak flux is ~250 times of the average flux in 7 years. Rather similar behaviors are observed in blazars and the blazar model can reasonably reproduce the spectral energy distribution of III Zw 2 in a wide energy range, strongly suggesting that its central engine resembles that of blazars. In view of its core, which shares radio similarities with young radio sources, together with weak extended radio lobe emission, we suggest that III Zw 2 harbors a recurrent activity core and thus serves as a valuable target for investigating the fueling and triggering of the activity in radio-loud active galactic nuclei.
- ID:
- ivo://CDS.VizieR/J/AJ/123/2206
- Title:
- BRI photometry of 3 QSO fields
- Short Name:
- J/AJ/123/2206
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the acquisition and analysis of imaging data for the identification of galaxies associated with z~4 damped Ly{alpha} systems. We present deep BRI images of three fields known to contain four z~4 damped systems. We discuss the reduction and calibration of the data, detail the color criteria used to identify z~4 galaxies, and present a photometric redshift analysis to complement the color selection. We have found no galaxy candidates closer to the QSO than 7" that could be responsible for the damped Ly{alpha} systems. Assuming that at least one of the galaxies is not directly beneath the QSO, we set an upper limit on this damped Ly {alpha} system of L<L^*^_LBG_/4. Finally, we have established a Web site to release these imaging data to the public, at http://kingpin.ucsd.edu/~dlaimg/papers/refern.html . The observations where made with LRIS on the Keck II telescope, on 13 Jan 1999 for PSS 0132+1341 and BR 0951-0450, and 23 Jan 1999 for PSS 1443+2724.
- ID:
- ivo://CDS.VizieR/J/A+A/561/L8
- Title:
- BRJK photometry of Seyfert galaxy WPVS48
- Short Name:
- J/A+A/561/L8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using robotic telescopes of the Universitatssternwarte Bochum near Cerro Armazones in Chile, we monitored the z=0.0377 Seyfert 1 galaxy WPVS48 in the optical (B and R) and near-infrared (NIR, J and K) with a cadence of two days.
- ID:
- ivo://CDS.VizieR/J/A+A/579/A113
- Title:
- BR light curves of GJ1214b
- Short Name:
- J/A+A/579/A113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The atmospheric composition and vertical structure of the super-Earth GJ 1214b has been a subject of debate since its discovery in 2009. Recent studies have indicated that high-altitude clouds might mask the lower layers. However, some data points that were gathered at different times and facilities do not fit this picture, probably because of a combination of stellar activity and systematic errors. We observed two transits of GJ 1214b with the Large Binocular Camera, the dual-channel camera at the Large Binocular Telescope. For the first time, we simultaneously measured the relative planetary radius k=R_p_/R_*_ at blue and red optical wavelengths (B+R), thus constraining the Rayleigh scattering on GJ 1214b after correcting for stellar activity effects. To the same purpose, a long-term photometric follow-up of the host star was carried out with WiFSIP at STELLA, revealing a rotational period that is significantly longer than previously reported. Our new unbiased estimates of k yield a flat transmission spectrum extending to shorter wavelengths, thus confirming the cloudy atmosphere scenario for GJ 1214b.
