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- ID:
- ivo://CDS.VizieR/J/A+A/621/A133
- Title:
- ABYSS HUDF WFC3 IR mosaics
- Short Name:
- J/A+A/621/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Ultra Deep field (HUDF) is the deepest region ever observed with the Hubble Space Telescope. With the main objective of unveiling the nature of galaxies up to z~7-8, the observing and reduction strategy have focused on the properties of small and unresolved objects, rather than the outskirts of the largest objects, which are usually over-subtracted. We aim to create a new set of WFC3 IR mosaics of the HUDF using novel techniques to preserve the properties of the low surface brightness regions. We created ABYSS a pipeline that optimises the estimate and modelling of low-level systematic effects to obtain a robust background subtraction. We have improved four key points in the reduction: 1) creation of new absolute sky flat fields, 2) extended persistence models, 3) dedicated sky background subtraction and 4) robust co-adding. The new mosaics successfully recover the low surface brightness structure removed on the previous HUDF published reductions. The amount of light recovered with a mean surface brightness dimmer than mu=26mag/arcsec^2^ is equivalent to a m=19 mag source when compared to the XDF and a m=20mag compared to the HUDF12. We present a set of techniques to reduce ultra-deep images (mu>32.5mag/arcsec^2^, 3 sigma in 10x10 arcsec boxes), that successfully allow to detect the low surface brightness structure of extended sources on ultra deep surveys. The developed procedures are applicable to HST, JWST, EUCLID and many other space and ground-based observatories. We made the final ABYSS WFC3 IR HUDF mosaics publicly available at http://www.iac.es/proyecto/abyss/.
- ID:
- ivo://mast.stsci/acsggct
- Title:
- ACS Galactic Globular Cluster Survey (ACSGGCT)
- Short Name:
- HST.ACSGGCT
- Date:
- 22 Jul 2020 22:26:50
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The ACSGGCT program used the HST ACS/WFC instrument to obtain uniform imaging of 65 of the nearest globular clusters to provide an extensive homogeneous dataset for a broad range of scientific investigations. An overview of the project was published by Sarajedini, A. et al. 2007, "The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous Hubble Space Telescope Photometry" AJ, 133, 1658.
- ID:
- ivo://archive.stsci.edu/hst/acs
- Title:
- Advanced Camera for Surveys
- Short Name:
- HST.ACS
- Date:
- 23 Jul 2020 19:47:47
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- HST Advanced Camera for Surveys (ACS) - Images: CCD images between 3,700 - 11
- ID:
- ivo://mast.stsci/angrrr
- Title:
- Archive of Nearby Galaxies: Reduce, Reuse, Recycle (ANGRRR)
- Short Name:
- HST.ANGRRR
- Date:
- 22 Jul 2020 22:28:43
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- An archive of stellar photometry for galaxies within 3.5 Mpc, excluding Local Group galaxies, based on primary and parallel wide-filter UV and optical observations taken with HST ACS/WFC or WFPC2.The sample includes all observations taken through Dec. 2008, as well as observations taken as part of Cycle 16 Supplemental GO programs 11986 and 11987. This release includes the ANGST targets within 3.5 Mpc; these observations have been rereduced using updated CTE corrections and zeropoints. Galaxies with 3.5 < D <= 5 Mpc will be included in a later release.
- ID:
- ivo://CDS.VizieR/B/assocdata
- Title:
- Associated data in VizieR
- Short Name:
- B/assocdata
- Date:
- 20 Mar 2022 05:13:55
- Publisher:
- CDS
- Description:
- The ObsCore VizieR table gather FITS images, spectra and time-series into a single table. The contents are the VizieR associated data, publilished in original article with the tables. The metadata comes from the ObsCore Data Model. ObsCore (Tody et al. 2011) is a standard of the Virtual Observatory used to map images,spectra or time-series resources with standardized metadata.
- ID:
- ivo://archive.stsci.edu/befs
- Title:
- Berkeley Extreme and Far-UV Spectrometer
- Short Name:
- BEFS
- Date:
- 22 Jul 2020 21:27:59
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The Berkeley Extreme and Far-UV Spectrometer (BEFS), flew on the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph (ORFEUS)-SPAS I and II space shuttle missions in 1993 and 1996, returning high-resolution (/3000) FUV spectra (900-1200 Å) of 75 astrophysical objects from the first flight and more than 100 from the second. EUV spectra (400-900 Å) were obtained for a subset of these targets.
- ID:
- ivo://mast.stsci/ssap/befs
- Title:
- Berkeley Extreme and Far-UV Spectrometer
- Short Name:
- BEFS
- Date:
- 03 Feb 2021 15:45:57
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The Berkeley Extreme and Far-UV Spectrometer (BEFS), flew on the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph (ORFEUS)-SPAS I and II space shuttle missions in 1993 and 1996, returning high-resolution (/3000) FUV spectra (900-1200 Å) of 75 astrophysical objects from the first flight and more than 100 from the second. EUV spectra (400-900 Å) were obtained for a subset of these targets.
- ID:
- ivo://CDS.VizieR/J/A+A/643/A110
- Title:
- beta Cas BRITE and SMEI light curves
- Short Name:
- J/A+A/643/A110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- F type stars are characterised by several physical processes such as different pulsation mechanisms, rotation, convection, diffusion, and magnetic fields. The rapidly rotating delta Scuti star beta Cas can be considered as a benchmark star to study the interaction of several of these effects. We investigate the pulsational and magnetic field properties of beta Cas. We also determine the star's apparent fundamental parameters and chemical abundances. Based on photometric time series obtained from three different space missions (BRITE-Constellation, SMEI, and TESS), we conduct a frequency analysis and investigate the stability of the pulsation amplitudes over four years of observations. We investigate the presence of a magnetic field and its properties using spectropolarimetric observations taken with the Narval instrument by applying the Least Square Deconvolution and Zeeman Doppler Imaging techniques. beta Cas shows only three independent p-mode frequencies down to the few ppm-level; its highest amplitude frequency is suggested to be a n=3, l=2, m=0 mode. Its magnetic field structure is quite complex and almost certainly of a dynamo origin. beta Cas' atmosphere is slightly deficient in iron peak elements and slightly overabundant in C, O, and heavier elements. Atypically for delta Scuti stars, we can only detect three pulsation modes down to exceptionally low noise levels for beta Cas.The star is also one of very few delta Scuti pulsators known to date to show a measurable magnetic field, and the first delta Scuti star with a dynamo magnetic field. These characteristics make beta Cas an interesting target for future studies of dynamo processes in the thin convective envelopes of F-type stars, of the transition region between fossil and dynamo fields, and the interaction between pulsations and magnetic field.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A28
- Title:
- beta Pic BRITE, bRing, SMEI light curves
- Short Name:
- J/A+A/627/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Exoplanet properties crucially depend on the parameters of their host stars: more accurate stellar parameters yield more accurate exoplanet characteristics. When the exoplanet host star shows pulsations, asteroseismology can be used for an improved description of the stellar parameters. We aim to revisit the pulsational properties of {beta} Pic and identify its pulsation modes from normalized amplitudes in five different passbands. We also investigate the potential presence of a magnetic field. We conducted a frequency analysis using three seasons of BRITE-Constellation observations in the two BRITE filters, the about 620-day-long bRing light curve, and the nearly 8-year-long SMEI photometric time series. We calculated normalized amplitudes using all passbands and including previously published values obtained from ASTEP observations. We investigated the magnetic properties of {beta} Pic using spectropolarimetric observations conducted with the HARPSpol instrument. Using 2D rotating models, we fit the normalized amplitudes and frequencies through Monte Carlo Markov chains. We identify 15 pulsation frequencies in the range from 34 to 55d^-1^, where two, F13 at 53.6917d^-1^ and F11 at 50.4921d^-1^, display clear amplitude variability. We use the normalized amplitudes in up to five passbands to identify the modes as three l=1, six l=2, and six l=3 modes. {beta} Pic is shown to be non-magnetic with an upper limit of the possible undetected dipolar field of 300 Gauss. Multiple fits to the frequencies and normalized amplitudes are obtained, including one with a near equator-on inclination for {beta} Pic, which corresponds to our expectations based on the orbital inclination of {beta} Pic b and the orientation of the circumstellar disk. This solution leads to a rotation rate of 27% of the Keplerian breakup velocity, a radius of 1.497+/-0.025R_{sun}_, and a mass of 1.797+/-0.035M_{sun}_. The ~2% errors in radius and mass do not account for uncertainties in the models and a potentially erroneous mode-identification.
