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- ID:
- ivo://CDS.VizieR/J/AJ/135/850
- Title:
- Properties of eclipsing binaries found in TrES
- Short Name:
- J/AJ/135/850
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In recent years, we have witnessed an explosion of photometric time-series data, collected for the purpose of finding a small number of rare sources, such as transiting extrasolar planets and gravitational microlenses. Once combed, these data are often set aside, and are not further searched for the many other variable sources that they undoubtedly contain. To this end, we describe a pipeline that is designed to systematically analyze such data, while requiring minimal user interaction. We ran our pipeline on a subset of the Trans-Atlantic Exoplanet Survey dataset, and used it to identify and model 773 eclipsing binary systems. For each system we conducted a joint analysis of its light curve, colors, and theoretical isochrones. This analysis provided us with estimates of the binary's absolute physical properties, including the masses and ages of their stellar components, as well as their physical separations and distances. We identified three types of eclipsing binaries that are of particular interest and merit further observations. The first category includes 11 low-mass candidates, which may assist current efforts to explain the discrepancies between the observation and the models of stars at the bottom of the main sequence. The other two categories include 34 binaries with eccentric orbits, and 20 binaries with abnormal light curves. Finally, this uniform catalog enabled us to identify a number of relations that provide further constraints on binary population models and tidal circularization theory.
- ID:
- ivo://CDS.VizieR/J/MNRAS/435/3206
- Title:
- Properties of field RR Lyrae variables
- Short Name:
- J/MNRAS/435/3206
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use accurate absolute UCAC4 proper motions, V-band photoelectric and CCD photometry including our own and compiled data, WISE W1-band mid-IR photometry, as well as extensive compiled radial-velocity and [Fe/H] data for 403 Galactic field RR Lyrae type variables to determine the kinematical parameters of the Galactic RR Lyrae population and constrain the zero-points of the V-, W1-, and Ks-band period-metallicity-luminosity relations for RR Lyraes via statistical parallax.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A29
- Title:
- Properties of galactic PNe central stars
- Short Name:
- J/A+A/593/A29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained multi-wavelength observations of compact Galactic planetary nebulae (PNe) to probe post-asymptotic giant branch (AGB) evolution from the onset of nebular ejection. We analyze new observations from Hubble Space Telescope to derive the masses and evolutionary status of their central stars (CSs) in order to better understand the relationship between the CS properties and those of the surrounding nebulae. We work with HST/WFC3 images of 51 targets obtained in a snapshot survey (GO-11657). The high spatial resolution of HST allows us to resolve these compact PNe and distinguish the CS emission from that of their surrounding PNe. The targets were imaged through the filters F200LP, F350LP, and F814W from which we derive Johnson V and I magnitudes. We derive CS bolometric luminosities and effective temperatures using the Zanstra technique, from a combination of HST photometry and ground-based spectroscopic data. We present new unique photometric measurements of 50 CSs, and derived effective temperatures and luminosities for most of them.
- ID:
- ivo://CDS.VizieR/J/ApJ/539/136
- Title:
- Properties of poor groups of galaxies. III.
- Short Name:
- J/ApJ/539/136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The form of the galaxy luminosity function (GLF) in poor groups - regions of intermediate galaxy density that are common environments for galaxies - is not well understood. Multiobject spectroscopy and wide-field CCD imaging now allow us to measure the GLF of bound group members directly (i.e., without statistical background subtraction) and to compare the group GLF with the GLFs of the field and of rich clusters. We use R-band images in 1.5x1.5degree^2^ mosaics to obtain photometry for galaxies in the fields of six nearby (2800<cz<7700km/s) poor groups for which we have extensive spectroscopic data, including 328 new galaxy velocities.
- ID:
- ivo://CDS.VizieR/J/AJ/159/25
- Title:
- PS1 light curves and rotation periods of new asteroids
- Short Name:
- J/AJ/159/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The intranight trajectories of asteroids can be approximated by straight lines, and so are their intranight detections. Therefore, the Hough transform, a line detecting algorithm, can be used to connect the line-up detections to find asteroids. We applied this algorithm to a high-cadence Pan-STARRS 1 (PS1) observation, which was originally designed to collect asteroid light curves for rotation period measurements. The algorithm recovered most of the known asteroids in the observing fields and, moreover, discovered 3574 new asteroids with magnitude mainly of 21.5<w_p1_<22.5mag. This magnitude range is equivalent to subkilometer main-belt asteroids (MBAs), which usually lack rotation period measurements due to their faintness. Using the light curves of the 3574 new asteroids, we obtained 122 reliable rotation periods, of which 13 are super-fast rotators (SRFs; i.e., rotation period of <2hr). The required cohesion to survive these SFRs range from tens to thousands of Pa, a value consistent with the known SFRs and the regolith on the Moon and Mars. The higher chance of discovering SFRs here suggests that subkilometer MBAs probably harbor more SFRs.
- ID:
- ivo://CDS.VizieR/J/ApJ/710/1498
- Title:
- QSO luminosity function at z~4
- Short Name:
- J/ApJ/710/1498
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The evolution of the quasar luminosity function (QLF) is one of the basic cosmological measures providing insight into structure formation and mass assembly in the universe. We have conducted a spectroscopic survey to find faint quasars (-26.0<M_1450_<-22.0) at redshifts z=3.8-5.2 in order to measure the faint end of the QLF at these early times. Using available optical imaging data from portions of the NOAO Deep Wide-Field Survey and the Deep Lens Survey, we have color-selected quasar candidates in a total area of 3.76deg^2^. Thirty candidates have R<=23mag. We conducted spectroscopic follow-up for 28 of our candidates and found 23 QSOs, 21 of which are reported here for the first time, in the 3.74<z<5.06 redshift range.
- ID:
- ivo://CDS.VizieR/J/MNRAS/309/48
- Title:
- QSOs redshifts and spectra in ESO/SERC field 927
- Short Name:
- J/MNRAS/309/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the spectra and redshifts of 62 quasars, from observations made with the Cerro Tololo Inter-American Observatory (CTIO) 4-m Blanco Telescope. These quasars form part of a total sample of 118 (with 56 having been published previously), which is being used for analysis of structure in the early universe. Quasars of particular interest are noted, including eight broad absorption line (BAL) quasars and two quasars with unusual emission spectra. Finally, we include a short summary of the present status of the large quasar group (LQG) that was discovered by Clowes & Campusano (1991, Cat. J/MNRAS/249/218 and 1994, Cat. J/MNRAS/266/317) from the earlier observations. The quasars are from an area ~25.3deg^2^ of ESO/SERC field 927, which is centred at (B1950) 10h 40m 00s, 05{deg} 00'00".
- ID:
- ivo://CDS.VizieR/J/MNRAS/266/317
- Title:
- Quasars in ESO/SERC field 927
- Short Name:
- J/MNRAS/266/317
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the spectroscopic observations of 56 quasars that were discovered by AQD (Automated Quasar Detection) in a field of ~25.3deg2, centred at (1950) RA l0h40m00s, Dec. 05deg00'00". These observations, with the CTIO 4-m telescope, led to the discovery by Clowes & Campusano of a large group of quasars with size ~100-200h^-1^Mpc at z~1.3. Quasars of particular interest are noted, including one that is a BAL quasar with z~1.78.
- ID:
- ivo://CDS.VizieR/J/ApJ/768/37
- Title:
- Radio emission from SDSS quasars
- Short Name:
- J/ApJ/768/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the 1.4GHz NVSS to study radio sources in two color-selected QSO samples: a volume-limited sample of 1313 QSOs defined by M_i_<-23 in the redshift range 0.2<z<0.45 and a magnitude-limited sample of 2471 QSOs with m_r_<=18.5 and 1.8<z<2.5. About 10% were detected above the 2.4mJy NVSS catalog limit and are powered primarily by active galactic nuclei (AGNs). The space density of the low-redshift QSOs evolves as {rho}{prop.to}(1+z)^6^. In both redshift ranges the flux-density distributions and luminosity functions of QSOs stronger than 2.4mJy are power laws, with no features to suggest more than one kind of radio source. Extrapolating the power laws to lower luminosities predicts the remaining QSOs should be extremely radio quiet, but they are not. Most were detected statistically on the NVSS images with median peak flux densities S_p_(mJy/beam){approx}0.3 and 0.05 in the low- and high-redshift samples, corresponding to spectral luminosities log [L_1.4GHz_(W/Hz)]{approx}22.7 and 24.1, respectively. We suggest that the faint radio sources are powered by star formation at rates dM/dt~20M_{sun}_/yr in the moderate luminosity (median <M_i_>{approx}-23.4) low-redshift QSOs and dM/dt~500M_{sun}_/yr in the very luminous (<M_i_>{approx}-27.5) high-redshift QSOs. Such luminous starbursts [<log(L_IR_/L_{sun}_)>~11.2 and 12.6, respectively] are consistent with "quasar mode" accretion in which cold gas flows fuel both AGN and starburst.
