J/A+A/611/A1 SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm (Meftah+, 2018)
SOLAR-ISS, a new reference spectrum based on SOLAR/SOLSPEC observations.
Meftah M., Dame L., Bolsee D., Hauchecorne A., Pereira N., Sluse D.,
Cessateur G., Irbah A., Bureau J., Weber M., Bramstedt K., Hilbig T.,
Thieblemont R., Marchand M., Lefevre F., Sarkissian A., Bekki S.
<Astron. Astrophys. 611, A1 (2018)>
=2018A&A...611A...1M 2018A&A...611A...1M (SIMBAD/NED BibCode)
ADC_Keywords: Sun ; Spectra, ultraviolet
Keywords: Sun: fundamental parameters - Sun: general
Abstract:
Since April 5, 2008 and up to February 15, 2017, the SOLar
SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the
International Space Station (ISS) has performed accurate measurements
of solar spectral irradiance (SSI) from the middle ultraviolet to the
infrared (165 to 3088nm). These measurements are of primary
importance for a better understanding of solar physics and the impact
of solar variability on climate. In particular, a new reference solar
spectrum (SOLAR-ISS) is established in April 2008 during the solar
minima of cycles 23-24 thanks to revised engineering corrections,
improved calibrations, and advanced procedures to account for thermal
and aging corrections of the SOLAR/SOLSPEC instrument.
The main objective of this article is to present a new high-resolution
solar spectrum with a mean absolute uncertainty of 1.26% at 1σ
from 165 to 3000nm. This solar spectrum is based on solar
observations of the SOLAR/SOLSPEC space-based instrument.
The SOLAR/SOLSPEC instrument consists of three separate double
monochromators that use concave holographic gratings to cover the
middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our
best ultraviolet, visible, and infrared spectra are merged into a
single absolute solar spectrum covering the 165-3000nm domain. The
resulting solar spectrum has a spectral resolution varying between 0.6
and 9.5nm in the 165-3000nm wavelength range. We build a new solar
reference spectrum (SOLAR-ISS) by constraining existing
high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that
purpose, we account for the difference of resolution between the two
spectra using the SOLAR/SOLSPEC instrumental slit functions.
Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000nm
wavelength range is built and is representative of the 2008 solar
minimum. It has a resolution better than 0.1nm below 1000nm and 1nm
in the 1000-3000nm wavelength range. The new solar spectrum
(SOLAR-ISS) highlights significant differences with previous solar
reference spectra and with solar spectra based on models. The integral
of the SOLAR-ISS solar spectrum yields a total solar irradiance of
1372.3±16.9W/m2 at 1σ, that is yet 11W/m2 over the value
recommended by the International Astronomical Union in 2015.
Description:
The SOLAR/SOLSPEC space-based instrument has measured the solar
spectral irradiance from 165 to 3000nm at 0.6 to 9.5nm spectral
resolution during the almost nine years of the SO- LAR/ISS mission.
The instrument was calibrated using the PTB standard blackbody
developed for temperatures up to 3200K. The absolute accuracy, based
on a detailed analysis of error sources, indicates a mean absolute
uncertainty of 1.26% of the total solar irradiance in the 165-3000nm
range. Using SOLAR/SOLSPEC data, a new solar spectrum (SOLAR-ISS)
covering the 165-3000nm wavelength range is built with added high
spectral resolution. This SOLAR-ISS spectrum is developed by
combining high spectral resolution from reference solar spectra with
the resulting SOLAR/SOLSPEC spectrum through the knowledge of the slit
functions of the SOLAR/SOLSPEC instrument.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
spectrum.dat 44 48581 *SOLAR-ISS spectrum, Version: 1.1,
Date: 18-October-2017
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Note on spectrum.dat: SOLAR/SOLSPEC Spectral Irradiance - 0.5-3000nm,
Reference: April 2008 solar minimum.
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See also:
J/A+A/531/A6 : Evolution of solar irradiance during Holocene (Vieira+, 2011)
J/AJ/112/2274 : Spectral irradiance calibration. VII. (Cohen+ 1996)
J/AJ/112/241 : Spectral irradiance calibration. VI. (Cohen+ 1996)
J/ApJ/789/117 : Solar spectral irradiance (Marchenko+, 2014)
J/A+A/562/A133 : Irradiated atmospheres analytical model (Parmentier+, 2014)
J/A+A/574/A35 : Irradiated atmospheres analytical model (Parmentier+, 2015)
J/A+A/581/A26 : Solar Lyman irradiance line profiles (Lemaire+, 2015)
J/other/SoPh/291.3527 : SOLAR/SOLSPEC UV SSI from 2008-2015 (Meftah+, 2016)
Byte-by-byte Description of file: spectrum.dat
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Bytes Format Units Label Explanations
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1- 13 F13.8 nm lambda Wavelength
19- 28 F10.8 W/m2/nm SSI ?=- Solar spectral irradiance
34- 44 F11.8 % e_SSI ?=- Uncertainty on SSI (k=1)
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Acknowledgements:
Mustapha Meftah, Mustapha.Meftah(at)latmos.ipsl.fr
(End) Patricia Vannier [CDS] 20-Oct-2017