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1. BATSE earth occultation deep sample results
ID:
ivo://CDS.VizieR/J/ApJS/154/585
Title:
BATSE earth occultation deep sample results
Short Name:
J/ApJS/154/585
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Burst and Transient Source Experiment (BATSE), aboard the Compton Gamma Ray Observatory (CGRO), provided a record of the low-energy gamma-ray sky (~20-1000keV) between 1991 April and 2000 May (9.1yr). We performed a deep-sampling of 58 objects, plus a selection of 121 more objects, combining data from the entire 9.1yr BATSE data set. Source types considered were primarily accreting binaries, but a small number of representative active galaxies, X-ray-emitting stars, and supernova remnants were also included. The sample represents a compilation of sources monitored and/or discovered with BATSE and other high-energy instruments between 1991 and 2000, known sources taken from the HEAO 1 A-4 (1984ApJS...54..581L) and Macomb & Gehrels (1999ApJS..120..335M, Cat. <J/ApJS/120/335>) catalogs. Flux data for the deep sample are presented in four energy bands: 2040, 4070, 70160, and 160430keV. The limiting average flux level (9.1yr) for the sample varies from 3.5 to 20mcrab (5{sigma}) between 20 and 430keV, depending on systematic error, which in turn is primarily dependent on the sky location.
2. BATSE occultation catalog of Gamma-Ray sources
ID:
ivo://CDS.VizieR/J/ApJS/127/79
Title:
BATSE occultation catalog of Gamma-Ray sources
Short Name:
J/ApJS/127/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the powerful Earth-occultation technique, long-term, nearly continuous monitoring of the entire low-energy gamma-ray sky is now possible with the advent of BATSE, the Burst and Transient Source Experiment on board the Compton Gamma Ray Observatory (CGRO). In this paper, we present a catalog of 34 moderately strong gamma-ray sources measured by BATSE. It consists of 0.03 - 1.8 MeV photon spectra averaged over weeks and months, and light curves of the 35 - 200 keV flux, with 1 day resolution, covering the first three phases of the CGRO mission (1991 May through 1994 October). This database contains a complete record of {~}1200 daily source count rates in 14 energy channels along with the corresponding Poisson and systematic errors.
3. Chariklo's system from stellar occultations
ID:
ivo://CDS.VizieR/J/A+A/652/A141
Title:
Chariklo's system from stellar occultations
Short Name:
J/A+A/652/A141
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Centaur (10199) Chariklo has the first rings system discovered around a small object. It was first observed using stellar occultation in 2013. Stellar occultations allow the determination of sizes and shapes with kilometre accuracy and obtain characteristics of the occulting object and its vicinity. Using stellar occultations observed between 2017 and 2020, we aim at constraining Chariklo's and its rings physical parameters. We also determine the rings' structure, and obtain precise astrometrical positions of Chariklo. We predicted and organised several observational campaigns of stellar occultations by Chariklo. Occultation light curves were measured from the data sets, from which ingress and egress times, and rings' width and opacity were obtained. These measurements, combined with results from previous works, allow us to obtain significant constraints on Chariklo's shape and rings' structure. We characterise Chariklo's ring system (C1R and C2R), and obtain radii and pole orientations that are consistent with, but more accurate than, results from previous occultations. We confirmed the detection of W-shaped structures within C1R and an evident variation of radial width. The observed width ranges between 4.8 and 9.1km with a mean value of 6.5km. One dual observation (visible and red) does not reveal any differences in the C1R opacity profiles, indicating ring particle's size larger than a few microns. The C1R ring eccentricity is found to be smaller than 0.022 (3-sigma), and its width variations may indicate an eccentricity higher than 0.005. We fit a tri-axial shape to Chariklo's detections over eleven occultations and determine that Chariklo is consistent with an ellipsoid with semi-axes of 143.8, 135.2 and 99.1km. Ultimately, we provided seven astrometric positions at a milliarcseconds accuracy level, based on Gaia EDR3, and use it to improve Chariklo's ephemeris.
4. 10199 Chariklo stellar occultation: 1999-2005
ID:
ivo://CDS.VizieR/J/AJ/119/2008
Title:
10199 Chariklo stellar occultation: 1999-2005
Short Name:
J/AJ/119/2008
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Flagstaff Astrometric Scanning Transit Telescope was used to scan the sky in search of occultation candidates through which the Centaur 10199 Chariklo (formerly 1997 CU_26_) will pass in 1999-2005. Positions for 96,397 stars (magnitudes 7.5<V<17.3) were determined using differential reductions to the ACT catalog of star positions and proper motions, and accuracies of +/-30mas were achieved for well-exposed images. The ephemeris for 10199 Chariklo was improved by including the new positions presented in this paper and, second, by correcting older positions taken from the literature for systematic errors. During this time period, 10199 Chariklo passes within 2" of 117 of these stars, which are identified as occultation candidates in this paper. Among these, 28 candidates have magnitudes V<15.0, making them the best choices for observing programs using portable telescopes. Circumstances for each occultation are given. Because the angular radius of 10199 Chariklo is only about 15mas, the astrometry provided in this paper is only accurate enough for identifying possible occultation events and is not sufficient for predicting individual shadow paths across the surface of Earth, although representative cases are given. Last-minute astrometry with a large-aperture telescope will be needed to refine each prediction.
5. Chiron occultations
ID:
ivo://CDS.VizieR/J/AJ/107/1814
Title:
Chiron occultations
Short Name:
J/AJ/107/1814
Date:
21 Oct 2021
Publisher:
CDS
Description:
A photographic search was conducted for stars that may be occulted by the unusual solar system object (2060) Chiron during the period from fall 1993 through summer 1996. 44 candidates were identified to a limiting V magnitude of 16, and for which the minimum appulse separation with Chiron is predicted to be less than 2.5arcsec. The successful observation of a stellar occultation by Chiron would give a direct measure of its diameter (currently estimated to be between 60 and 300km), and would help considerably in constraining Chiron's surface properties and volatile makeup. If at the time of the occultation, Chiron exhibits a significant coma, there is also the potential for measuring the optical-depth profile of the dust in its inner coma.
6. Detection of the secondary eclipse of Qatar-1b
ID:
ivo://CDS.VizieR/J/A+A/595/A61
Title:
Detection of the secondary eclipse of Qatar-1b
Short Name:
J/A+A/595/A61
Date:
21 Oct 2021
Publisher:
CDS
Description:
Qatar-1b is a close-orbiting hot Jupiter (Rp~=1.18R_J_, Mp~=1.33M_J_) around a metal-rich K-dwarf, with orbital separation and period of 0.023AU and 1.42-days. We have observed the secondary eclipse of this exoplanet in the Ks band with the objective of deriving a brightness temperature for the planet and providing further constraints to the orbital configuration of the system. We obtained near-infrared photometric data from the ground by using the OMEGA2000 instrument at the 3.5m telescope at Calar Alto (Spain) in staring mode, with the telescope defocused. We have used principal component analysis (PCA) to identify correlated systematic trends in the data. A Markov chain Monte Carlo analysis was performed to model the correlated systematics and fit for the secondary eclipse of Qatar-1b using a previously developed occultation model. We adopted the prayer bead method to assess the effect of red noise on the derived parameters.
7. FORS2 transmission spectroscopy of WASP-17b
ID:
ivo://CDS.VizieR/J/A+A/596/A47
Title:
FORS2 transmission spectroscopy of WASP-17b
Short Name:
J/A+A/596/A47
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present FORS2 (attached to ESO's Very Large Telescope) observations of the exoplanet WASP-17b during its primary transit, for the purpose of differential spectrophotometry analysis. We use the instrument in its Mask eXchange Unit (MXU) mode to simultaneously obtain low resolution spectra of the planet hosting star, as well as several reference stars in the field of view. The integration of these spectra within broadband and smaller 100{AA} bins provides us with 'white' and spectrophotometric light curves, from 5700 to 8000{AA}. Through modelling the white light curve, we obtain refined bulk and transit parameters of the planet, as well as wavelength-dependent variations of the planetary radius from smaller spectral bins through which the transmission spectrum is obtained. The inference of transit parameters, as well as the noise statistics, is performed using a Gaussian Process model. We achieve a typical precision in the transit depth of a few hundred parts per million from various transit light curves. From the transmission spectra we rule out a flat spectrum at >3{sigma} and detect marginal presence of the pressure-broadened sodium wings. Furthermore, we detect the wing of the potassium absorption line in the upper atmosphere of the planet with 3-{sigma} confidence, both facts pointing to a relatively shallow temperature gradient in the atmosphere. These conclusions are mostly consistent with previous studies of this exo-atmosphere, although previous potassium measurements have been inconclusive.
8. Galilean Satellites mutual events 2002-2003
ID:
ivo://CDS.VizieR/J/A+A/383/719
Title:
Galilean Satellites mutual events 2002-2003
Short Name:
J/A+A/383/719
Date:
21 Oct 2021
Publisher:
CDS
Description:
Mutual occultations and eclipses of the Galilean satellites of Jupiter will occur in 2002-2003. This paper provides predictions of these events as well as information useful for their observations. Such events are uncommon, since they occur only every 6 years when the Earth and the Sun pass through the common orbital plane of the Galilean satellites. Therefore, we encourage professional and amateur astronomers to join the networks of observers in order to get as many observations as possible. Data on the predictions of the events are available on the web server of the Institut de Mecanique Celeste et de Calcul de Ephemerides (IMCCE) ( http://www.bdl.fr ).
9. Galilean satellites mutual events in 1997
ID:
ivo://CDS.VizieR/J/A+A/314/312
Title:
Galilean satellites mutual events in 1997
Short Name:
J/A+A/314/312
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper provides the predictions of the mutual phenomena of the Galilean satellites which will occur in 1997. Past experiences have shown the interest of the observation of such events very rare, since they occur only every 6 years when the Earth and the Sun pass through the common orbital plane of the Galilean satellites.
10. KPNO lunar occultation summary
ID:
ivo://CDS.VizieR/J/AJ/141/10
Title:
KPNO lunar occultation summary
Short Name:
J/AJ/141/10
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results for 251 lunar occultation events recorded at Kitt Peak National Observatory are presented, including 20 observations of known or suspected double stars and five measurements of stars with resolved angular diameters.