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- ID:
- ivo://archive.stsci.edu/hst/stis
- Title:
- Space Telescope Imaging Spectrograph
- Short Name:
- HST.STIS
- Date:
- 23 Jul 2020 19:50:49
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The Space Telescope Imaging Spectrograph (STIS) was installed in HST on Feb. 14, 1997, replacing the GHRS spectrograph. STIS provides spectra and images at ultraviolet and visible wavelengths, probing the Universe from our solar system out to cosmological distances.
- ID:
- ivo://CDS.VizieR/J/A+A/501/291
- Title:
- Spectroscopic observations of HD 152219
- Short Name:
- J/A+A/501/291
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 152219 is a massive binary system with O9.5 III + B1-2 V/III components and a short orbital period of 4.2d. Its primary component further displays clear line profile variability (LPV). The primary component being located within the pulsational instability domain predicted for high-luminosity stars, we previously suggested that the observed LPV could be associated with non-radial pulsations. The aim of the present work is to determine the nature of the observed LPV in the spectrum of the primary component of HD 152219. During a 4-night FEROS monitoring campaign, we collected a new set of 134 high signal-to-noise spectra. These new observations were then used to re-investigate the variability of different line profiles in the spectrum of HD~152219. Based on the present analysis, we discard the non-radial pulsations and point out the Rossiter-McLaughlin effect as the cause of the LPV in HD 152219. The upper limit on the amplitude of possible weak pulsations is set at a few parts per thousand of the continuum level.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A85
- Title:
- Starspot rotation rates vs. activity cycle phase
- Short Name:
- J/A+A/622/A85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During the solar magnetic activity cycle the emergence latitudes of sunspots change, leading to the well-known butterfly diagram. This phenomenon is poorly understood for other stars since starspot latitudes are generally unknown. The related changes in starspot rotation rates caused by latitudinal differential rotation can however be measured. Using the set of 3093 Kepler stars with activity cycles identified by Reinhold et al. (2017A&A...603A..52R, Cat. J/A+A/603/A52), we aim to study the temporal change in starspot rotation rates over magnetic activity cycles, and how this relates to the activity level, the mean rotation rate of the star, and its effective temperature. We measured the photometric variability as a proxy for the magnetic activity and the spot rotation rate in each quarter over the duration of the Kepler mission. We phase-fold these measurements with the cycle period. To reduce random errors we perform averages over stars with comparable mean rotation rates and effective temperature at fixed activity-cycle phases. We detect a clear correlation between the variation of activity level and the variation of the starspot rotation rate. The sign and amplitude of this correlation depends on the mean stellar rotation and -- to a lesser extent -- on the effective temperature. For slowly rotating stars (rotation periods between 15-28 days) the starspot rotation rates are clearly anti-correlated with the level of activity during the activity cycles. A transition is observed around rotation periods of 10-15 days, where stars with effective temperature above 4200K instead show positive correlation. Our measurements can be interpreted in terms of a stellar "butterfly diagram", but these appear different from the Sun's since the starspot rotation rates are either in phase or anti-phase with the activity level. Alternatively, the activity cycle periods observed by Kepler are short (around 2.5 years) and may therefore be secondary cycles, perhaps analogous to the solar quasi-biennial oscillations.
115. Swift Master Catalog
- ID:
- ivo://CDS.VizieR/B/swift
- Title:
- Swift Master Catalog
- Short Name:
- B/swift
- Date:
- 20 Mar 2022 06:12:03
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://archive.stsci.edu/catalogs/TESSINPUT
- Title:
- TESS Input Catalog ConeSearch
- Short Name:
- TIC CS
- Date:
- 06 May 2024 13:23:15
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The TESS Input Catalog is a comprehensive collection of 1.73 billion sources on the sky, providing stellar parameters for evaluation of potential planetary transit signals. It combines sources from many other catalogs, including 2MASS, LAMOST, SuperBlink, HSOY, RAVE, APOGEE, UCAC, KIC, EPIC, Tycho-2, APASS, AllWISE, SDSS, Gaia DR2, and Hipparcos. It was constructed for the TESS mission to serve as a source for selecting targets to observe with the TESS two-minute cadence, and to provide stellar parameter information for evaluating the properties of transit candidates. MAST catalog holdings are available via Cone Search endpoints. All available missions are listed at http://archive.stsci.edu/vo/mast_services.html. This service provides access to the TESS input catalog (TIC), currently version 8.2.
- ID:
- ivo://CDS.VizieR/J/A+A/625/L13
- Title:
- TESS light curve of beta Pictoris
- Short Name:
- J/A+A/625/L13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We search for signs of falling evaporating bodies (FEBs, also known as exocomets) in photometric time series obtained for {beta} Pictoris after fitting and removing its {delta} Scuti-type pulsation frequencies. Using photometric data obtained by the TESS satellite we determined the pulsational properties of the exoplanet host star {beta} Pictoris through frequency analysis. We then pre-whitened the 54 identified {delta} Scuti p-modes and investigated the residual photometric time series for the presence of FEBs. We identify three distinct dipping events in the light curve of {beta} Pictoris over a 105-day period. These dips have depths from 0.5 to 2-millimagnitudes and durations of up to 2-days for the largest dip. These dips are asymmetric in nature and are consistent with a model of an evaporating comet with an extended tail crossing the disc of the star. We present the first broadband detections of exocomets crossing the disc of {beta} Pictoris, complementing the predictions made 20 years earlier by Lecavelier Des Etangs et al. (1999A&A...343..916L). No periodic transits are seen in this time series. These observations confirm the spectroscopic detection of exocomets in calcium H and K lines that have been seen in high resolution spectroscopy.
- ID:
- ivo://archive.stsci.edu/catalogs/atlas
- Title:
- The ATLAS All-Sky Stellar Reference Catalog ConeSearch
- Short Name:
- ATLAS CS
- Date:
- 13 Feb 2020 17:09:38
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- All MAST catalog holdings are available via Cone Search endpoints. This service provides access to the ATLAS All-Sky Stellar Reference Catalog. The Asteroid Terrestrial-impact Last Alert System (ATLAS) observes most of the sky every night in search of dangerous asteroids. Its data are also used to search for photometric variability, where sensitivity to variability is limited by photometric accuracy. Since each exposure spans 7.6 deg corner to corner, variations in atmospheric transparency in excess of 0.01 mag are common, and 0.01 mag photometry cannot be achieved by using a constant flat field calibration image. We therefore have assembled an all-sky reference catalog of approximately one billion stars to m~19 from a variety of sources to calibrate each exposure's astrometry and photometry. Gaia DR2 is the source of astrometry for this ATLAS Refcat2. The sources of g, r, i, z photometry include Pan-STARRS DR1, the ATLAS Pathfinder photometry project, ATLAS re-flattened APASS data, SkyMapper DR1, APASS DR9, the Tycho-2 catalog, and the Yale Bright Star Catalog. We have attempted to make this catalog at least 99% complete to m less than 19, including the brightest stars in the sky. We believe that the systematic errors are no larger than 5 millimag RMS, although errors are as large as 20 millimag in small patches near the galactic plane. All available missions are listed at http://archive.stsci.edu/vo/mast_services.html.
- ID:
- ivo://CDS.VizieR/B/chandra
- Title:
- The Chandra Archive Log
- Short Name:
- B/chandra
- Date:
- 07 Mar 2022 06:17:49
- Publisher:
- CDS
- Description:
- The Chandra X-Ray Observatory (CXO) is a high-resolution (< 0.5 arcsecond) X-ray telescope with a suite of advanced imaging and spectroscopic instruments. The Observatory was successfully launched by NASA's Space Shuttle Columbia on July 23, 1999. Chandra was designed to provide order-of-magnitude advances over previous X-ray astronomy missions with regards to spatial and spectral resolution. The High Resolution Mirror Assembly (HRMA) produces images with a half-power diameter (HPD) of the point spread function (PSF) of < 0.5 arcsec. Chandra has two focal plane science instruments, i) The Advanced CCD Imaging Spectrometer (ACIS), and ii) The High Resolution Camera (HRC). ACIS is comprised of two CCD arrays, a 4-chip array, ACIS-I ; and a 6-chip array, ACIS-S . ACIS-I was designed for CCD imaging and spectrometry; ACIS-S can be used both for CCD imaging spectrometry and also for high-resolution spectroscopy in conjunction with the HETG grating. A mix of ACIS-S and ACIS-I chips (up to six) may be used for imaging observations. The HRC is comprised of two microchannel plate (MCP ) imaging detectors: the HRC-I designed for wide-field imaging; and, HRC-S designed to serve as a readout for the LETG . The grating systems consist of the Low Energy Transmission Grating (LETG) and the High Energy Transmission Grating (HETG). The HETG , when operated with the HRMA and the ACIS-S , forms the High-Energy Transmission Grating Spectrometer (HETGS ) for high resolution spectroscopy . The HETGS achieves resolving power up to 1000 in the band between 0.4 keV and 10.0 keV. The LETG when operated with the HRC-S , forms the Low Energy Transmission Grating Spectrometer (LETGS ). The LETGS provides the highest spectral resolution on Chandra at low (0.08 - 0.2 keV) energies. This catalogue is a copy of the Chandra Observation Catalog from the Chandra Data Archive (CDA) which is part of the Chandra X-Ray Observatory Science Center (CXC) which is operated for NASA by the Smithsonian Astrophysical Observatory.
- ID:
- ivo://CDS.VizieR/IX/24
- Title:
- The Einstein Observatory HRI Source List
- Short Name:
- IX/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Einstein Observatory is the second of NASA's three High Energy Astrophysical Observatories, HEAO-2, renamed Einstein after launch, and was the first fully imaging X-ray telescope put into space. It observed in the energy range 0.2-20keV. It was launched on 12 November 1978, and remained in operation until April 1981. The High Resolution Imager (HRI) is one fo the four instruments aboard the Einstein Observatory, operating in the 0.2-3.0keV energy range, with a spatial resolution of a few arcseconds, and a field of view of 25arcmin. Field and source parameters observed with this instrument are given here.
