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Related papers: Faint white dwarf flux standards: data and models

200 papers

The CALSPEC database of absolute spectral energy distributions (SEDs) from the Hubble Space Telescope (HST) is based on pure hydrogen model atmosphere calculations for three unreddened white dwarf (WD) stars and represents the current UV…

Instrumentation and Methods for Astrophysics · Physics 2019-02-20 Ralph C. Bohlin , Luciana Bianchi

Non-local Thermodynamic Equilibrium (NLTE) calculations of hot white dwarf (WD) model atmospheres are the cornerstone of modern flux calibrations for the Hubble Space Telescope (HST) and for the CALSPEC database. These theoretical spectral…

Solar and Stellar Astrophysics · Physics 2020-06-17 Ralph Bohlin , Ivan Hubeny , Thomas Rauch

We present 5,080 white dwarf (WD) candidates selected from stars matching between the multi-band imaging datasets of the Subaru Hyper Suprime-Cam (HSC) Survey and the Sloan Digital Sky Survey (SDSS) in the Stripe82 region covering about…

Astrophysics of Galaxies · Physics 2024-12-16 Tian Qiu , Masahiro Takada , Naoki Yasuda , Akira Tokiwa , Kazumi Kashiyama , Yoshihisa Suzuki , Kenta Hotokezaka

This paper presents new trigonometric parallaxes and proper motions for 214 stars. The measurements were made at the US Naval Observatory Flagstaff Station (NOFS) between 1989 and 2017, and the average uncertainty in the parallax values is…

It is critical for James Webb Space Telescope (JWST) science that instrumental units are converted to physical units. We detail the design of the JWST absolute flux calibration program that has the core goal of ensuring a robust flux…

We calibrate spectrophotometric optical spectra of 32 stars commonly used as standard stars, referenced to 14 stars already on the HST-based CALSPEC flux system. Observations of CALSPEC and non-CALSPEC stars were obtained with the SuperNova…

Ultraviolet observations using the Solar Blind Channel on the Hubble Space Telescope provide light curves and low resolution spectra of three pulsating white dwarfs in the cataclysmic variables SDSS013132.39-090122.3,…

We use star counts from 13 deep HST fields imaged with the {\it Wide Field Camera - 2} in order to constrain the amount of dark matter in the Galaxy that can be in the form of low-mass main sequence stars or white-dwarfs. Based on the…

Astrophysics · Physics 2015-06-24 Basilio X. Santiago , Gerard Gilmore , Rebecca A. W. Elson

An accurate tabulation of stellar brightness in physical units is essential for a multitude of scientific endeavors. The HST/CALSPEC database of flux standards contains many stars with spectral coverage in the 0.115--1 \micron\ range with…

Instrumentation and Methods for Astrophysics · Physics 2022-06-22 Ralph C. Bohlin , Jessica E. Krick , Karl D. Gordon , Ivan Hubeny

A challenge in absolute calibration is to relate very bright stars with physical flux measurements to faint ones within range of modern instruments, e.g. those on large groundbased telescopes or on the James Webb Space Telescope (JWST). We…

Solar and Stellar Astrophysics · Physics 2022-01-12 G. H. Rieke , K. Y. L. Su , G. C. Sloan , E. Schlawin

Taking advantage of the now available Gaia EDR3 parallaxes, we carry out an archival {\it Hubble Space Telescope} (HST) far ultraviolet spectroscopic analysis of 10 cataclysmic variable systems, including 5 carefully selected eclipsing…

Solar and Stellar Astrophysics · Physics 2022-03-30 Patrick Godon , Edward M. Sion

In this study, we demonstrate the efficacy of the Ultraviolet Imaging Telescope (UVIT) in identifying and characterizing white dwarfs (WDs) within the Milky Way Galaxy. Leveraging the UVIT point source catalogue towards SMC and…

We present the absolute flux and wavelength calibration of the James Webb Space Telescope (JWST) Near-Infrared Camera (NIRCam) Wide Field Slitless Spectroscopy (WFSS) mode. Each of NIRCam's two modules (A and B) provides independent long…

Instrumentation and Methods for Astrophysics · Physics 2026-02-19 Nor Pirzkal , Martha Boyer , Russel E. Ryan

We have calibrated the 6.5 m James Webb Space Telescope (JWST) mid-infrared filters as star formation rate indicators, using JWST photometry synthesized from $Spitzer$ spectra of 49 low redshift galaxies, which cover a wider luminosity…

Astrophysics of Galaxies · Physics 2018-12-26 Madhooshi R. Senarath , Michael J. I. Brown , Michelle E. Cluver , John Moustakas , Lee Armus , T. H. Jarrett

We present comprehensive catalogs of hot star candidates in the Milky Way, selected from GALEX far-UV (FUV, 1344-1786 AA) and near-UV (NUV, 1771-2831 AA) imaging. The FUV and NUV photometry allows us to extract the hottest stellar objects,…

Solar and Stellar Astrophysics · Physics 2015-05-20 Luciana Bianchi , Boryana Efremova , James Herald , Leo Girardi , Alexandre Zabot , Paola Marigo , Christopher Martin

The upcoming Chinese Space Station Telescope (CSST) slitless spectroscopic survey poses a challenge of flux calibration, which requires a large number of flux-standard stars. In this work, we design an uncertainty-aware residual attention…

Instrumentation and Methods for Astrophysics · Physics 2024-01-25 Lin Yang , Haibo Yuan , Fuqing Duan , Ruoyi Zhang , Bowen Huang , Kai Xiao , Shuai Xu , Jinming Zhang

White dwarf studies carry significant implications across multiple fields of astrophysics, including exoplanets, supernova explosions, and cosmological investigations. Thus, accurate determinations of their fundamental parameters (Teff and…

We present a catalog of 71,364 point-like UV sources with SDSS photometry and GALEX FUV-NUV less or equal 0.1mag. The limit corresponds to stellar Teff greater than 15,000 to 20,000K, slightly depending on gravity but nearly…

Solar and Stellar Astrophysics · Physics 2024-09-10 Luciana Bianchi

Spectral analysis needs the observation of lines of successive ionization stages in order to evaluate the ionization equilibrium (of a particular species) which is a sensitive indicator for the effective temperature. Since stars with…

Astrophysics · Physics 2007-06-18 Thomas Rauch , Klaus Werner

We present a new photometric calibration of the WFC3-UVIS and WFC3-IR detectors based on observations collected from 2009 to 2020 for four white dwarfs, namely GRW+70~5824, GD~153, GD~71, G191B2B, and a G-type star, P330E. These…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 A. Calamida , V. Bajaj , J. Mack , M. Marinelli , J. Medina , A. Pidgeon , V. Kozhurina-Platais , C. Shanahan , D. Som