The Gaia spectrophotometric standard stars survey – V. Preliminary flux tables for the calibration of Gaia DR2 and (E)DR3

ABSTRACT We present the flux tables of the spectrophotometric standard stars (SPSS) used to calibrate in flux the Gaia DR2 and (E)DR3 data releases. The latest SPSS grid version contains 112 stars, whose flux tables agree to better than 1 per cent with the CALSPEC spectra of 11 flux standards for the calibration of the Hubble Space Telescope. The synthetic magnitudes computed on the SPSS spectra also agree to better than 1 per cent with the Landolt magnitudes of 37 stars in common. The typical spreads in both comparisons are of the order of 1 per cent. These uncertainties already meet the initial requirements for the Gaia SPSS project, but further improvements are expected in the next SPSS versions, that will be used to calibrate future Gaia releases. We complement the SPSS flux tables with literature spectra of 60 additional stars that did not pass all the criteria to be SPSS, the Passband Validation Library (PVL). The PVL contains stars of extreme spectral types, such as bright O and B stars and late M stars and brown dwarfs, and was useful to investigate systematic effects in the previous Gaia DR2 release and to minimize them in the EDR3 one. The PVL literature spectra are recalibrated as accurately as possible on to the SPSS reference scale, so that the two sets together can be used in a variety of validation and comparison studies.

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Photometric Properties of the Hubble Space Telescope Fine Guidance Sensors

International Astronomical Union Colloquium ◽

10.1017/s0252921100057195 ◽

2000 ◽

Vol 176 ◽

pp. 82-82 ◽

Cited By ~ 1

Author(s):

K. Zwintz ◽

R. Kuschnig ◽

W. W. Weiss ◽

A. Witeschnik

Keyword(s):

Hubble Space Telescope ◽

Noise Levels ◽

Space Telescope ◽

Systematic Effects ◽

Lower Noise

AbstractTo reach lower noise levels with the Hubble Space Telescope Fine Guidance Sensors (FGS) the photometric properties as well as the systematic effects affecting the data have been investigated.

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The Use of the Hubble Space Telescope for Global Reference Frame Work

Highlights of Astronomy ◽

10.1017/s1539299600006250 ◽

1986 ◽

Vol 7 ◽

pp. 87-88

Author(s):

P. D. Hemenway

Keyword(s):

Transfer Functions ◽

Hubble Space Telescope ◽

Field Of View ◽

Optimum Conditions ◽

Small Aperture ◽

Space Telescope ◽

Frame Work ◽

Global Reference Frame ◽

Better Than ◽

Small Field Of View

The Hubble Space Telescope (HST) will have the capability of making relative astrometric measurements with an accuracy of four to ten times better than similar ground based measurements. The instruments of choice will be the Fine Guidance Sensors (FGS’s). Details of the instrumentation have been given elsewhere (c.f. Jefferys, 1980). Each FGS consists of two interferometer detectors which look at a small aperture located within a larger field of view (FOV). The raw data consist of encoder readings, from “star selectors”, and error signals derived from the interferometer transfer functions. The star selector positions determine the position of the small aperture within the pickles. The precision is always less than 0.001 arcsec, with an expected accuracy of 0.002 to 0.003 arcsec per observation. Under optimum conditions, the best expected accuracy is 0.0016 arcsec per observation. An observation will consist of the relative positions of several objects in one pickle. Thus the highest accuracy observations will be relative observations within a relatively small field of view.

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Cloud Atlas: Hubble Space Telescope Near-infrared Spectral Library of Brown Dwarfs, Planetary-mass Companions, and Hot Jupiters

The Astronomical Journal ◽

10.3847/1538-3881/aaf88f ◽

2019 ◽

Vol 157 (3) ◽

pp. 101 ◽

Cited By ~ 10

Author(s):

Elena Manjavacas ◽

Dániel Apai ◽

Yifan Zhou ◽

Ben W. P. Lew ◽

Glenn Schneider ◽

...

Keyword(s):

Near Infrared ◽

Hubble Space Telescope ◽

Brown Dwarfs ◽

Spectral Library ◽

Space Telescope ◽

Hot Jupiters ◽

Planetary Mass ◽

Infrared Spectral ◽

Cloud Atlas

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Hubble Space Telescope Observations of Extragalactic Jets

Symposium - International Astronomical Union ◽

10.1017/s0074180900080505 ◽

1996 ◽

Vol 175 ◽

pp. 195-200 ◽

Cited By ~ 11

Author(s):

F. Duccio Macchetto

Keyword(s):

Hubble Space Telescope ◽

Space Telescope ◽

Central Source ◽

Radio Jets ◽

Extended Radio ◽

Extragalactic Jets ◽

The Subject ◽

Radio Band ◽

Better Than

The study of the optical counterparts to the radio jets has been the subject of a number of observing programs with the Hubble Space Telescope (HST). We know that these jets play a fundamental role in transporting energy from the central source to the extended radio lobes. Observations at optical and ultraviolet wavelengths with the HST are essential to obtain spatial resolutions similar to, or better than, those achieved in the radio band and, thus, provide the possibility of directly comparing the sites and mechanisms responsible for the emission at these different wavelengths.

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Extending Gaia DR2 with HST narrow-field astrometry – II. Refining the method on WISE J163940.83−684738.6★

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa540 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2068-2075

Author(s):

L R Bedin ◽

C Fontanive

Keyword(s):

High Precision ◽

Reference System ◽

Hubble Space Telescope ◽

High Accuracy ◽

Test Case ◽

Wide Field ◽

Brown Dwarf ◽

Space Telescope ◽

Infra Red ◽

Gaia Dr2

ABSTRACT In the second paper of this series, we perfected our method of linking high-precision Hubble Space Telescope astrometry to the high-accuracy Gaia DR2 absolute reference system to overcome the limitations of relative astrometry with narrow-field cameras. Our test case here is the Y brown dwarf WISE J163940.83−684738.6, observed at different epochs spread over a 6-yr time baseline with the Infra-Red channel of the Wide Field Camera 3. We derived significantly improved astrometric parameters compared to previous determinations, finding (μαcos δ, μδ, ϖ) = (577.21 ± 0.24 mas yr−1, −3108.39 ± 0.27 mas yr−1, 210.4 ± 1.8 mas). In particular, our derived absolute parallax (ϖ ) corresponds to a distance of 4.75 ± 0.05 pc for the faint ultracool dwarf.

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