J/A+A/608/L8 Calibration of G passband for Gaia DR1 (Maiz Apellaniz 2017)
Calibration of the photometric G passband for Gaia Data Release 1.
Maiz Apellaniz J.
<Astron. Astrophys. 608, L8 (2017)>
=2017A&A...608L...8M 2017A&A...608L...8M (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Photometry, G band
Keywords: surveys - methods: data analysis - techniques: photometric
Abstract:
On September 2016 the first data from Gaia were released (DR1). The
first release included photometry for over 109 sources in the very
broad G system.
To test the correspondence between G magnitudes in DR1 and the
synthetic equivalents derived using spectral energy distributions from
observed and model spectrophotometry. To correct the G passband curve
and to measure the zero point in the Vega system. Methods. I have
computed the synthetic G and Tycho-2 BTVT photometry for a sample of
stars using the Next Generation Spectral Library (NGSL) and the Hubble
Space Telescope (HST) CALSPEC spectroscopic standards.
I have found that the nominal G passband curve is too blue for the DR1
photometry, as shown by the presence of a color with an exponent of
0.783 eliminates the color term. The corrected passband has a Vega
zero point of 0.070±0.004 magnitudes.
Description:
File table1 contains the nominal and the corrected total-system
passbands and file table2 contains the stars used for the calculation
of the correction.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 20 362 Nominal and corrected total-system passbands
table2.dat 64 84 Stars used for the correction
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 nm lambda Wavelength
6- 12 F7.5 --- Nominal Nominal total-system passband
14- 20 F7.5 --- Corrected Corrected total-system passband
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Star Star name
18- 36 I19 --- ID Gaia DR1 identification (source_id)
38- 39 I2 h RAh Right ascension (J2000)
41- 42 I2 min RAm Right ascension (J2000)
44- 49 F6.3 s RAs Right ascension (J2000)
51 A1 --- DE- Declination sign (J2000)
52- 53 I2 deg DEd Declination (J2000)
55- 56 I2 arcmin DEm Declination (J2000)
58- 62 F5.2 arcsec DEs Declination (J2000)
64 A1 --- Flag [NC] SED source (N: NGSL, C: CALSPEC) (1)
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Note (1): SED source as follows:
N = NGSL
C = CALSPEC
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Acknowledgements:
Jesus Maiz Apellaniz
(End) Patricia Vannier [CDS] 01-Dec-2017