Search

Start Over Subject photometry
3791. Main-belt asteroids optical light curves
ID:
ivo://CDS.VizieR/J/A+A/596/A40
Title:
Main-belt asteroids optical light curves
Short Name:
J/A+A/596/A40
Date:
21 Oct 2021
Publisher:
CDS
Description:
Because the second reaction wheel failed, a new mission was conceived for the otherwise healthy Kepler space telescope. In the course of the K2 mission, the telescope is staring at the plane of the Ecliptic. Thousands of solar system bodies therefore cross the K2 fields and usually cause additional noise in the highly accurate photometric data. We here follow the principle that some person's noise is another person's signal and investigate the possibility of deriving continuous asteroid light curves. This is the first such endeavor. In general, we are interested in the photometric precision that the K2 mission can deliver on moving solar system bodies. In particular, we investigate space photometric optical light curves of main-belt asteroids. We studied the K2 superstamps that cover the fields of M35, and Neptune together with Nereid, which were observed in the long-cadence mode (29.4min sampling). Asteroid light curves were generated by applying elongated apertures. We used the Lomb-Scargle method to determine periodicities that are due to rotation.
3792. Main-sequence A, F, G, and K stars photometry
ID:
ivo://CDS.VizieR/J/ApJ/771/40
Title:
Main-sequence A, F, G, and K stars photometry
Short Name:
J/ApJ/771/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color-temperature relations to an assortment of color indices in the Johnson (BVR_J_I_J_JHK), Cousins (R_C_I_C_), Kron (R_K_I_K_), Sloan (griz), and WISE (W_3_W_4_) photometric systems. These relations have an average standard deviation of ~3% and are valid for stars with spectral types A0-M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T_eff_>6750K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only ~2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.
3793. Main sequence intrinsic colours: O8V to M0V
ID:
ivo://CDS.VizieR/J/MNRAS/418/2219
Title:
Main sequence intrinsic colours: O8V to M0V
Short Name:
J/MNRAS/418/2219
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new Monte Carlo method has been developed in order to derive ages of young embedded clusters in massive star-forming regions where there is strong differential reddening. After foreground and infrared excess source candidates are removed, each cluster candidate star is individually dereddened. Simulated clusters are constructed using isochrones, an initial mass function, realistic photometric errors, simulated background field populations and extinction distributions. These synthetic clusters are then dereddened in the same way as the real data, obtained from a deep near-infrared survey, and used to derive the ages of three embedded clusters. Results were found to be consistent with those determined using spectrophotometric methods. This new method provides way to determine the ages of embedded clusters when only photometric data are available and there is strong differential reddening.
3794. Main sequence of NGC 6171
ID:
ivo://CDS.VizieR/J/A+A/298/461
Title:
Main sequence of NGC 6171
Short Name:
J/A+A/298/461
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep J, K IR-array photometry for individual Main Sequence stars in NGC 6171 reaching K~18, about two magnitudes below the turnoff, is presented. The observations were made during 3 nights on June 1993 at the 2.2m ESO/MPI telescope at ESO (La Silla), equipped with the IR-array camera IRAC2.
3795. Maintaining the Ephemeris of 20 CoRoT planets
ID:
ivo://CDS.VizieR/J/other/JAVSO/48.201
Title:
Maintaining the Ephemeris of 20 CoRoT planets
Short Name:
J/other/JAVSO/48
Date:
22 Feb 2022
Publisher:
CDS
Description:
We present 33 transit minimum times of 20 transiting planets discovered by the CoRoT space mission, which have been obtained from ground-based observations since the mission's end in 2012, with the objective to maintain the ephemeris of these planets and to identify potential transit time variations. Twelve of the observed planets are in the CoRoT fields near the galactic center and the remaining eight planets are in the fields near the anticenter. We detect indications for significant transit timing variations in the cases of CoRoT 3b, 11b, 13b, 27b. For two more planets (CoRoT 18b and 20b) we conclude that timing offsets in early follow-up observations led to ephemeris in discovery publications that are inconsistent with timings from follow-up observations in later epochs. In the case of CoRoT-20b, this might be due to the influence from a further non-transiting planet. We also note that a significant majority (23 of 33) of our reported minimum times have negative O-C values, albeit most of them are within the expected uncertainty of the ephemeris.
3797. Major galaxy mergers at z<~3
ID:
ivo://CDS.VizieR/J/AJ/126/1183
Title:
Major galaxy mergers at z<~3
Short Name:
J/AJ/126/1183
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents direct evidence for hierarchical galaxy assembly out to redshifts z~3. We identify major mergers using the model-independent CAS (concentration, asymmetry, clumpiness) physical morphological system on galaxies detected, and photometrically selected, in the WFPC2 and NICMOS Hubble Deep Field North. We specifically use the asymmetric distributions of rest-frame optical light measured through the asymmetry parameter (A) to determine the fraction of galaxies undergoing major mergers as a function of redshift (z), stellar mass (M*), and absolute magnitude (M_B_).
3798. Makemake (136472) long-term photometry
ID:
ivo://CDS.VizieR/J/A+A/625/A46
Title:
Makemake (136472) long-term photometry
Short Name:
J/A+A/625/A46
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim to study the rotational properties of the dwarf planet Makemake. The photometric observations were carried out at different telescopes between 2006 and 2017. Most of the measurements were acquired in BVRI broad-band filters of a standard Johnson-Cousins photometric system. We found that Makemake rotates more slowly than was previously reported. A possible lightcurve asymmetry suggests a double-peaked period of P=22.8266+/-0.0001h. A small peak-to-peak lightcurve amplitude in R-filter A=0.032+/-0.005mag implies an almost spherical shape or near pole-on orientation. We also measured BVRI colours and the R-filter phase-angle slope and revised the absolute magnitudes. The absolute magnitude of Makemake remained unchanged since its discovery in 2005. No direct evidence of a newly discovered satellite was found in our photometric data, however we discuss the possible existence of another larger satellite.
3799. MAMBO observations of SWIRE sources
ID:
ivo://CDS.VizieR/J/ApJ/692/422
Title:
MAMBO observations of SWIRE sources
Short Name:
J/ApJ/692/422
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on-off pointed MAMBO observations at 1.2mm of 61 Spitzer-selected star-forming galaxies from the Spitzer Wide Area Infrared Extragalactic Legacy survey (SWIRE). The sources are selected on the basis of bright 24um fluxes (F24um>0.4mJy) and of stellar dominated near-infrared spectral energy distributions in order to favor z~2 starburst galaxies. The average 1.2mm flux for the whole sample is 1.5+/-0.2mJy. Our analysis focuses on 29 sources in the Lockman Hole field where the average 1.2mm flux (1.9+/-0.3mJy) is higher than in other fields (1.1+/-0.2mJy). The analysis of the multiwavelength spectral energy distributions indicates that these sources are starburst galaxies with far-infrared luminosities from 10^12^ to 10^13.3^L_{sun}_, and stellar masses of ~0.2-6x10^11^M_{sun}_. Compared to submillimeter selected galaxies (SMGs), the SWIRE-MAMBO sources are among those with the largest 24um/1.2mm flux ratios. The origin of such large ratios is investigated by comparing the average mid-infrared spectra and the stacked far-infrared spectral energy distributions of the SWIRE-MAMBO sources and of SMGs.
3800. MAMBO sources near NTT Deep Field
ID:
ivo://CDS.VizieR/J/ApJ/606/664
Title:
MAMBO sources near NTT Deep Field
Short Name:
J/ApJ/606/664
Date:
21 Oct 2021
Publisher:
CDS
Description:
We discuss identifications for 18 sources from our Max-Planck- Millimeter-Bolometer (MAMBO) 1.2mm survey of the region surrounding the NTT Deep Field. We have obtained accurate positions from Very Large Array 1.4GHz interferometry, and in a few cases IRAM millimeter interferometry, and have also made deep BVRIzJK imaging at ESO.