- 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.
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- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/112/2786
- Title:
- 1985-1995 lunar occultations at TIRGO
- Short Name:
- J/AJ/112/2786
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A program of observations of lunar occultations in the near-infrared was started at the TIRGO observatory in late 1985. After ten years of operation, we provide a list of all the events recorded up to the end of 1995 using the facility IR photometer. A total of 157 light curves were obtained, mostly aiming at measurements of angular diameters and binaries, with a total of 54 results in these fields. In Table 1 is reported a summary of the occultation events and the parameters of their observations. In Table 2 is reported a list of cross-identifications, coordinates, and characteristics.
- ID:
- ivo://CDS.VizieR/J/A+A/532/A101
- Title:
- Lunar occultations of 184 stellar sources
- Short Name:
- J/A+A/532/A101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Lunar occultations (LO) provide a unique combination of high angular resolution and sensitivity at near-infrared wavelengths. At the ESO Very Large Telescope, it is possible to achieve about 1 milliarcsecond (mas) resolution and detect sources as faint as K~12mag. We have taken advantage of a passage of the Moon over two crowded and reddened regions in the direction of the inner part of the Galactic bulge to obtain a high number of occultation light curves over two half nights. Our goal was to detect and characterize new binary systems, and to investigate highly extincted and relatively unknown infrared sources in search of circumstellar shells and similar peculiarities. Our target list included a significant number of very late-type stars, but the majority of the sources was without spectral classification.
- ID:
- ivo://CDS.VizieR/J/PASP/107/299
- Title:
- Occultation Binaries Catalog
- Short Name:
- J/PASP/107/299
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observation of lunar occultation phenomena allows for the determination of binary star data which can not always be obtained using classical techniques. No complete catalog has been compiled since that of Evans (1981a) in spite of a 99% increase in the available data. This catalog presents a catalog of photoelectric and occultation measures of binary and multiple systems complete through 1994.
- ID:
- ivo://CDS.VizieR/B/occ
- Title:
- Occultation lights curves
- Short Name:
- B/occ
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Lunar occultation light curves have been recorded since the mid-20th century using high-speed photomultipliers. Running at high cadence for high angular resolution, such recordings were usually made on large telescopes and limited to the brighter stars - and were not large in number. While a small number of video recordings of lunar and asteroidal occultations were made from about 1980, they became common from about the year 2000, when inexpensive low-light security cameras became available. As of 2016, almost all lunar and asteroidal occultation observations are recorded using video, with the video recording being measured using software packages such as Limovie [http://astro-limovie.info/limovie/limovie_en.html], and Tangra [http://www.hristopavlov.net/Tangra3/]. As a result, light curves are now routinely generated for almost all lunar and asteroidal occultation observations, especially those coordinated through the International Occultation Timing Association and related organisations around the world. This is resulting in large numbers of occultation light curves being obtained each year - albeit with some limitations on time resolution and signal-to-noise ratios. As of 2016, video recordings are mainly made using one or other of the two international video standards - NTSC, or PAL. Both NTSC and PAL use an interlaced video scan, whereby each frame of the video is comprised of two interlaced, time-sequential, fields. The frame rate of an NTSC system is 29.97 frames/sec (59.94 fields/sec), while that for PAL is 25 frames/sec ( 50 fields/sec). Consistent with broadcast television standards, the majority of video cameras used for recording occultations use 8-bit CCD's. However some video recordings are made using progressive scan, 12 to 16-bit digital video systems. For lunar occultations, the temporal resolution is governed by a combination of the frame (or field) rate of the video recording, and the rate of motion of the moon. The typical topocentric motion of the moon is between about 0.3"/sec and 0.4"/sec. The motion of the lunar limb in a direction normal to the star is reduced by the cosine of the difference between the direction of motion of the moon and the position angle of the star. As a result, the typical rate of motion of the lunar limb normal to the star is in the range 0.2 to 0.4 "/sec. At video frame rates this provides a spatial resolution of about 0.01" to 0.02" at frame rate, or 0.005" to 0.01" at field rate. In recent years it has been possible to accurately determine the orientation of the lunar limb at the point of an occultation, using data from the Japanese Kaguya satellite, and more recently the US Lunar Reconnaissance Orbiter - Lunar Orbiter Laser Altimeter (LRO-LOLA). The LRO-LOLA data allows the slope of the lunar limb to be reliably determined over circumferential distances of less than 0.2" in the sky plane. As a result, all data elements required to analyse a lunar occultation light curve are well determined - and are included in this archive. The motion of most asteroids is much less than the moon. As a result, the angular resolution attainable at video frame rate is much smaller than for a lunar occultation, and is commonly in the range 0.0001" to 0.001". However asteroidal occultations frequently involve fainter objects than for lunar occultations, and many observers use integrating video cameras to detect these fainter occultations; the resolution attainable with an integrating camera is reduced in proportion to the number of frames integrated. Unlike lunar occultations, the orientation of the occulting limb of an asteroid relative to the star is generally not well established. Furthermore it can generally be assumed that the limb of an asteroid is likely to have significant irregularities at scales greater than the potential angular resolution attainable, but smaller than the angular distance between adjacent observed occultation chords. There is also the issue of the rotational orientation of the asteroid differing for observers located at different points along the occultation path, placing a limit on the accuracy of the limb slope that can be derived from adjacent occultation chords. Accordingly, at this time the record does not attempt to specify the orientation of the limb of the asteroid at the occultation event.
- ID:
- ivo://CDS.VizieR/J/AJ/109/1363
- Title:
- Occultations of stars by asteroids 1995-96
- Short Name:
- J/AJ/109/1363
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Predictions, based on a computerized comparison of asteroid ephemerides with the catalog positions of 567,500 stars, are given for 155 occultations of stars by asteroids in 1995 and 1996. On average, the predictions are expected to be more accurate than in earlier searches because of the use of more modern star catalogs. A number of very favorable occultations, visible in North Armerica and elsewhere, are discussed.
- ID:
- ivo://CDS.VizieR/J/PAZh/30/692
- Title:
- Occultations of stars by large TNO 2004-2014
- Short Name:
- J/PAZh/30/692
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Occultations of stars brighter than 15m by largest trans-Neptunian objects (TNOs) are predicted. Search was performed using the following catalogues: Hipparcos (Cat. <I/239>; Tycho2 (Cat. <I/259>) with coordinates of 2838666 stars taken from UCAC2 (Herald, 2003); UCAC2 (Zacharias et al., 2003, Cat. <I/289>) with 16356096 stars between 12.00 and 14.99mag to the north from -45{deg} declination. Predictions were made for 17 largest numbered transneptunian asteroids and 4 known binary Kuiper Belt objects. 67 events occuring at solar elongation of 30{deg} and more are selected. Observations of these occultations by all available means are extremely important since they can give unique information about the size of TNOs and improve their orbits dramatically. Finder charts and preliminary path plots are available separately at http://hea.iki.rssi.ru/~denis/TNOocc.html of by E-mail to denis@hea.iki.rssi.ru
