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Related papers: NICMOS Spectrophotometry and Models for A-Stars

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Absolute flux distributions for seven solar analog stars are measured from 0.3 to 2.5 \mu m by HST spectrophotometry.In order to predict the longer wavelength mid-IR fluxes that are required for JWST calibration, the HST SEDs are fit with…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. C. Bohlin

Exoplanets have sparked interest in extremely high signal-to-noise ratio spectroscopic observations of very bright stars, in a regime where flux calibrators, in particular DA white dwarfs, are not available. We argue that A-type stars offer…

Solar and Stellar Astrophysics · Physics 2015-12-09 Carlos Allende Prieto , Carlos del Burgo

Free of any atmospheric contamination, HST provides the best available spectrophotometry from the far-UV to the near-IR for stars as faint as V~16. The HST CALSPEC standard star network is based on 3 standard candles: the hot, pure hydrogen…

Astrophysics · Physics 2007-05-23 Ralph C. Bohlin

The measurement of precise absolute fluxes for stellar sources has been pursued with increased vigor since the discovery of the dark energy and the realization that its detailed understanding requires accurate spectral energy distributions…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Ralph C. Bohlin , Karl D. Gordon , P. -E. Tremblay

Observations from the Space Telescope Imaging Spectrograph define the flux of the DBQ4 star LDS749B from 0.12-1.0 \mu m with an uncertainty of ~1% relative to the three pure hydrogen WD primary HST standards. With T_{eff}=13575 K, log…

Astrophysics · Physics 2009-11-13 R. C. Bohlin , D. Koester

The Space Telescope Imaging Spectrograph has measured the absolute flux for Vega from 0.17-1.01 microns on the HST White Dwarf flux scale. These data are saturated by up to a factor of 80 overexposure but retain linearity to a precision of…

Astrophysics · Physics 2009-09-29 R. C. Bohlin , R. L. Gilliland

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

The spectrophotometric flux calibration of recent spectroscopic surveys has reached a limiting systematic precision of approximately 1-3 percent, and is often biased near the wavelengths associated with H I Balmer absorption. As we prepare…

Solar and Stellar Astrophysics · Physics 2026-01-12 Ryan Cooke , Nao Suzuki , J. Xavier Prochaska

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

The collections of spectral energy distributions (SEDs) in the \emph{Hubble Space Telescope} (HST) CALSPEC database are augmented by 19 IR SEDs from Wide Field Camera 3 (WFC3) IR grism spectra. Together, the two IR grisms, G102 and G141,…

Instrumentation and Methods for Astrophysics · Physics 2019-03-29 Ralph C. Bohlin , Susana E. Deustua

Newly acquired data and improved data reduction algorithms mandate a fresh look at the absolute flux calibration of the CCD cameras on the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The goals are to achieve a 1\%…

Instrumentation and Methods for Astrophysics · Physics 2016-08-31 Ralph C. Bohlin

We use data from the Transiting Exoplanet Survey Satellite (TESS) to search for, and set limits on, optical to near-infrared photometric variability of the well-vetted, candidate James Webb Space Telescope (JWST) spectrophotometric…

We present spectral energy distributions (SEDs) for 68 Herschel sources detected at 5-sigma at 250, 350 and 500 mu in the HerMES SWIRE-Lockman field. We explore whether existing models for starbursts, quiescent star-forming galaxies and for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Michael Rowan-Robinson , Herschel-SPIRE HerMES consortium

As part of a reanalysis of galactic Asymptotic Giant Branch (AGB) stars at infrared (IR) wavelengths, we discuss a sample (357) of carbon stars for which mass loss rates, near-IR photometry and distance estimates exist. For 252 sources we…

Astrophysics · Physics 2016-08-30 R. Guandalini , M. Busso , S. Ciprini , G. Silvestro , P. Persi

We have characterized 26 Spitzer/IRAC-selected sources from the SMUVS program that are undetected in the UltraVISTA DR5 H- and/or Ks-band images, covering 94 square arcmin of the COSMOS field which have deep multiwavelength JWST photometry.…

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

The absolute flux calibration of the James Webb Space Telescope will be based on a set of stars observed by the Hubble and Spitzer Space Telescopes. In order to cross-calibrate the two facilities, several A, G, and white dwarf (WD) stars…

We present a synopsis of the project to establish thirty-two new faint ($ 16.5 \leq V \leq 19.8 $) DA white dwarfs as spectrophotometric standards distributed over the whole sky. Our results validate the use of fully radiative pure hydrogen…

WFIRST microlensing observations will return high-precision parallaxes, sigma(pi) < 0.3 microarcsec, for the roughly 1 million stars with H<14 in its 2.8 deg^2 field toward the Galactic bulge. Combined with its 40,000 epochs of high…

Solar and Stellar Astrophysics · Physics 2017-01-18 A. Gould , D. Huber , M. Penny , D. Stello
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