- ID:
- ivo://CDS.VizieR/J/AJ/159/173
- Title:
- Photometry & RVs of 4 dwarfs hosting giant planets
- Short Name:
- J/AJ/159/173
- Date:
- 09 Dec 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four transiting giant planets around K-dwarfs. The planets HATS-47b, HATS-48Ab, HATS-49b, and HATS-72b have masses of 0.369_-0.021_^+0.031^M_J_, 0.243_-0.030_^+0.022^M_J_, 0.353_-0.027_^+0.038^M_J_, and 0.1254{+/-}0.0039M_J_, respectively, and radii of 1.117{+/-}0.014R_J_, 0.800{+/-}0.015R_J_, 0.765{+/-}0.013R_J_, and 0.7224{+/-}0.0032R_J_, respectively. The planets orbit close to their host stars with orbital periods of 3.9228days, 3.1317days, 4.1480days, and 7.3279days, respectively. The hosts are main-sequence K-dwarfs with masses of 0.674_-0.012_^+0.016^M_{odot}_, 0.7279{+/-}0.0066M_{odot}_, 0.7133{+/-}0.0075M_{odot}_, and 0.7311{+/-}0.0028, and with V-band magnitudes of V=14.829{+/-}0.010, 14.35{+/-}0.11, 14.998{+/-}0.040 and 12.469{+/-}0.010. The super-Neptune HATS-72b (a.k.a. WASP-191b and TOI294.01) was independently identified as a transiting planet candidate by the HATSouth, WASP, and TESS surveys, and we present a combined analysis of all of the data gathered by each of these projects (and their follow-up programs). An exceptionally precise mass is measured for HATS-72b thanks to high-precision radial velocity (RV) measurements obtained with VLT/ESPRESSO, FEROS, HARPS, and Magellan/PFS. We also incorporate TESS observations of the warm Saturn-hosting systems HATS-47 (a.k.a. TOI1073.01), HATS-48A, and HATS-49. HATS-47 was independently identified as a candidate by the TESS team, while the other two systems were not previously identified from the TESS data. The RV orbital variations are measured for these systems using Magellan/PFS. HATS-48A has a resolved 5.4" neighbor in Gaia DR2, which is a common-proper-motion binary star companion to HATS-48A with a mass of 0.22M_{odot}_ and a current projected physical separation of ~1400au.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/795/38
- Title:
- Photometry/spectroscopic measurements for KA1858+4850
- Short Name:
- J/ApJ/795/38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- KA1858+4850 is a narrow-line Seyfert 1 galaxy at redshift 0.078 and is among the brightest active galaxies monitored by the Kepler mission. We have carried out a reverberation mapping campaign designed to measure the broad-line region size and estimate the mass of the black hole in this galaxy. We obtained 74 epochs of spectroscopic data using the Kast Spectrograph at the Lick 3 m telescope from 2012 February to November, and obtained complementary V-band images from five other ground-based telescopes. We measured the H{beta} light curve lag with respect to the V-band continuum light curve using both cross-correlation techniques (CCF) and continuum light curve variability modeling with the JAVELIN method and found rest-frame lags of {tau}_CCF_=13.53_-2.32_^+2.03^ days and {tau}_JAVELIN_=13.15_-1.00_^+1.08^ days. The H{beta} rms line profile has a width of {sigma}_line_=770+/-49 km/s. Combining these two results and assuming a virial scale factor of f=5.13, we obtained a virial estimate of M_BH_=8.06_-1.72_^+1.59^x10^6^M_{sun}_ for the mass of the central black hole and an Eddington ratio of L/L_Edd_{approx}0.2. We also obtained consistent but slightly shorter emission-line lags with respect to the Kepler light curve. Thanks to the Kepler mission, the light curve of KA1858+4850 has among the highest cadences and signal-to-noise ratios ever measured for an active galactic nucleus; thus, our black hole mass measurement will serve as a reference point for relations between black hole mass and continuum variability characteristics in active galactic nuclei.
- ID:
- ivo://CDS.VizieR/J/ApJ/854/109
- Title:
- Photometry & spectroscopy follow-up of MWC 882
- Short Name:
- J/ApJ/854/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Disks in binary systems can cause exotic eclipsing events. MWC 882 (BD-224376, EPIC 225300403) is such a disk-eclipsing system identified from observations during Campaign 11 of the K2 mission. We propose that MWC 882 is a post-Algol system with a B7 donor star of mass 0.542+/-0.053M_{sun}_ in a 72-day orbit around an A0 accreting star of mass 3.24+/-0.29M_{sun}_. The 59.9+/-6.2R_{sun}_ disk around the accreting star occults the donor star once every orbit, inducing 19-day long, 7% deep eclipses identified by K2 and subsequently found in pre-discovery All-Sky Automated Survey and All Sky Automated Survey for Supernovae observations. We coordinated a campaign of photometric and spectroscopic observations for MWC 882 to measure the dynamical masses of the components and to monitor the system during eclipse. We found the photometric eclipse to be gray to ~1%. We found that the primary star exhibits spectroscopic signatures of active accretion, and we observed gas absorption features from the disk during eclipse. We suggest that MWC 882 initially consisted of a ~3.6M_{sun}_ donor star transferring mass via Roche lobe overflow to a ~2.1M_{sun}_ accretor in a ~7-day initial orbit. Through angular momentum conservation, the donor star is pushed outward during mass transfer to its current orbit of 72 days. The observed state of the system corresponds with the donor star having left the red giant branch ~0.3Myr ago, terminating active mass transfer. The present disk is expected to be short-lived (10^2^yr) without an active feeding mechanism, presenting a challenge to this model.
- ID:
- ivo://CDS.VizieR/J/AJ/117/102
- Title:
- Photometry + Spectroscopy in HDF + Flanking Fields
- Short Name:
- J/AJ/117/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an HK' wide-field survey encompassing the Hubble Deep Field and its flanking fields. Our wide-field survey provides uniform coverage of a 61.8arcmin^2^ area to a depth equivalent to K=20.1 at 5{sigma}. We have also imaged the Hubble Deep Field in HK', providing uniform coverage of a 7.8arcmin^2^ area to a depth equivalent to K=21.2 at 5{sigma}. Using these data in combination with new deep University of Hawaii 8K V- and I-imaging obtained on the Canada-France-Hawaii Telescope, we find only a small population of objects with colors redder than an equivalent I-K=4mag, the color expected for an evolved elliptical galaxy at z>1. We infer that only a fraction of the local field elliptical galaxy population with M_K_<-23.4 could have formed in single bursts at high redshift. The HK' observations of the HDF and its flanking fields were made with the University of Hawaii 2.2m telescope (1996-02-06 to 1996-02-08 for the HDF, and 1997-04-17 to 1997-04-22 for the wider area) and the 3.6m Canada-France-Hawaii Telescope (CFHT, 1996-04-05 to 1996-04-08 for the HDF). The deep V- and I-band observations were made with the CFHT (1997-04-03 to 1997-04-08), and B-band observations with the Keck Low Resolution Imaging Spectrograph in a strip across the center of the HK wide-field image.
- ID:
- ivo://CDS.VizieR/J/AJ/161/221
- Title:
- Photometry & spectroscopy of 4 binaries stars
- Short Name:
- J/AJ/161/221
- Date:
- 16 Mar 2022 11:53:19
- Publisher:
- CDS
- Description:
- We present the photometric and spectroscopic analysis of four W-UMa binaries J015829.5+260333 (hereinafter as J0158), J030505.1+293443 (hereinafter as J0305), J102211.7+310022 (hereinafter as J1022), and KW-Psc. The VRcIc band photometric observations are carried out with the 1.3m Devasthal Fast Optical Telescope (DFOT). For low-resolution spectroscopy, we used the 2m Himalayan Chandra Telescope (HCT) as well as the archival data from the 4m LAMOST survey. The systems J0158 and J0305 show a period increase rate of 5.26({+/-}1.72)x10^-7^days/yr and 1.78({+/-}1.52)x10^-6^days/yr, respectively. The period of J1022 is found to be decreasing with a rate of 4.22({+/-}1.67)x10^-6^days/yr. The period analysis of KW-Psc displays no change in its period. The PHOEBE package is used for the light-curve modeling and basic parameters are evaluated with the help of the GAIA parallax. The asymmetry of light curves is explained with the assumption of cool spots at specific positions on one of the components of the system. On the basis of temperatures, mass ratios, fill-out factors, and periods, the system J1022 is identified as a W-subtype system while the others show some mixed properties. To probe the chromospheric activities in these W-UMa binaries, their spectra are compared with the known inactive stars' spectra. The comparison shows emission in H{alpha}, H{beta}, and CaII. To understand the evolutionary status of these systems, the components are plotted in mass-radius and mass-luminosity planes with other well characterized binary systems. The secondary components of all the systems are away from ZAMS, which indicates that the secondary is more evolved than the primary component.
- ID:
- ivo://CDS.VizieR/J/A+A/639/A23
- Title:
- Photometry & spectroscopy of EE Cep: 2014-15
- Short Name:
- J/A+A/639/A23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- EE Cep is one of few eclipsing binary systems with a dark, dusty disk around an invisible object similar to epsilon Aur. The system is characterized by grey and asymmetric eclipses every 5.6yr, with a significant variation in their photometric depth, ranging from ~0.5mag to ~2.0mag. The main aim of the observational campaign of the EE Cep eclipse in 2014 was to test the model of disk precession (Galan et al. 2012). We expected that this eclipse would be one of the deepest with a depth of ~2m.mag. We collected multicolor observations from almost 30 instruments located in Europe and North America. This photometric data covers 243 nights during and around the eclipse. We also analyse the low- and high- resolution spectra from several instruments. The eclipse was shallow with a depth of 0m.71 in V-band. The multicolor photometry illustrates small color changes during the eclipse with a total amplitude of order ~+0.15mag in B-I color index. The linear ephemeris for this system is updated by including new times of minima, measured from the three most recent eclipses at epochs E=9, 10 and 11. New spectroscopic observations were acquired, covering orbital phases around the eclipse, which were not observed in the past and increased the data sample, filling some gaps and giving a better insight into the evolution of the H{alpha} and NaI spectral line profiles during the primary eclipse. The eclipse of EE Cep in 2014 was shallower than expected 0.71mag instead of ~2.0mag. This means that our model of disk precession needs revision.
- ID:
- ivo://CDS.VizieR/J/MNRAS/338/508
- Title:
- Photometry+spectroscopy of UCM galaxies
- Short Name:
- J/MNRAS/338/508
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the integrated properties of the stellar populations in the Universidad Complutense de Madrid (UCM) Survey of H{alpha}-selected galaxies. In this paper, the first of a series, we describe in detail the techniques developed to model star-forming galaxies using a mixture of stellar populations, and taking into account the observational uncertainties. We assume a recent burst of star formation superimposed on a more evolved population. The effects of the nebular continuum, line emission and dust attenuation are taken into account. We also test different model assumptions, including the choice of specific evolutionary synthesis model, initial mass function, star formation scenario and the treatment of dust extinction. Quantitative tests are applied to determine how well these models fit our multiwavelength observations for the UCM sample. Our observations span the optical and near-infrared, including both photometric and spectroscopic data. Our results indicate that extinction plays a key role in this kind of study, revealing that low- and high-obscured objects may require very different extinction laws and must be treated differently. We also demonstrate that the UCM Survey galaxies are best described by a short burst of star formation occurring within a quiescent galaxy, rather than by continuous star formation. A detailed discussion on the inferred parameters, such as the age, burst strength, metallicity, star formation rate, extinction and total stellar mass for individual objects, is presented in Paper II of this series.
- ID:
- ivo://CDS.VizieR/J/A+A/327/145
- Title:
- Photopolarimetric activity of RR Tauri
- Short Name:
- J/A+A/327/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of coordinated Crimea-Dodaira simultaneous multi-bands photometric and polarimetric observations of the classical Herbig Ae/Be star RR Tau which cover fully the observed interval of its brightness changes are presented. Within the observed interval of its light variations the linear polarization of RR Tau anti-correlates with its brightness changes.
- ID:
- ivo://CDS.VizieR/J/AZh/77/420
- Title:
- Photopolarimetric activity of SV Cep
- Short Name:
- J/AZh/77/420
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of the eleven-years (1987-98) photopolarimetric patrol observations of Herbig Ae star SV Cep are presented. Only one deep brightness minimum of star were observed during this time interval. The decrease of the SV Cep brightness during this minimum was accompanied by increase of its linear polarization. The similar behaviour of linear polarization with the brightness changes was found earlier in other young stars with the non-periodic Algol-type minima. The most probable interpretation of this phenomenon is based on the model in which the source of intrinsic linear polarization is the scattered radiation of circumstellar disk-like dust envelope (probably the proto-planetary disk). The deposition of this source increases during the brightness minima when the direct (non-polarized) stellar radiation are absorbed in the CS dust clouds intersected the line-of-sight.
- ID:
- ivo://CDS.VizieR/J/A+AS/112/457
- Title:
- Photopolarimetry of BM And
- Short Name:
- J/A+AS/112/457
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of photoelectric UBV observations of the T Tauri type variable BM And made during 1983-1991, as well as of simultaneous photopolarimetric UBVRI observations of this star for 1990-93 are given.