VI/159 High-resolution solar spectra (Meftah+, 2023)
The SOLAR-HRS new high-resolution solar spectra for disk-integrated,
disk-center, and intermediate cases.
Meftah M., Sarkissian A., Keckhut P., Hauchecorne A.
<Remote Sens., 15, 3560 (2023)>
=2023yCat.6159....0M 2023yCat.6159....0M
ADC_Keywords: Sun ; Spectroscopy
Keywords: solar radiation - solar spectrum - Fraunhofer lines - satellites -
MicroCarb - Uvsq-Sat NG
Abstract:
The solar spectrum at the top of the atmosphere contains crucial data
for solar physics, astronomy, and geophysics. Accurately determining
high-resolution solar reference spectra, whether they are
disk-integrated, disk-center, or intermediate cases, represents a new
challenge and is of primary importance for all applications where
spectral solar radiation needs to be evaluated. These spectra are also
essential for interpreting remote sensing measurements that rely on
sunlight, such as those obtained by Earth observation satellites or
spacecraft exploring other planets. This paper lays a foundation for
the implementation of multiple new solar irradiance reference spectra
that have high resolution and are representative of solar minimum
conditions. We developed the SOLAR high-resolution extraterrestrial
reference spectra (SOLAR-HRS disk-integrated spectra) by normalizing
high-spectral-resolution solar line data to the absolute irradiance
scale of the SOLAR-ISS reference spectrum. The resulting one-of-a-kind
SOLAR-HRS disk-integrated spectrum has a spectral resolution varying
between 0.001 and 1nm in the 0.5-4400nm wavelength range. We also
implemented a new high-resolution solar spectrum at the disk-center,
covering a range of 650-4400nm with a spectral resolution of 0.001 to
0.02nm. We further expanded our analysis by producing several solar
spectra for ten different solar view angles ranging from mu=0.9 to
mu=0.05 (SOLAR-HRS intermediate cases). Finally, we developed new
Merged Parallelised Simplified ATLAS spectra (MPS-ATLAS) based on
solar modeling with Kurucz and Vald3 solar linelists for both the
disk-integrated and disk-center spectra. One of the objectives of
implementing all these new solar spectra is to fulfill the
requirements of the MicroCarb space mission, which focuses on
measuring greenhouse gas emissions. The solar data of this study are
openly available at http://bdap.ipsl.fr/voscat_en/solarspectra.html .
Description:
SOLAR-HRS (disk-integrated) is a new high-resolution solar reference
spectrum developed by normalizing high-spectral-resolution solar line
data to the absolute irradiance scale of the SOLAR-ISS reference
spectrum. In the 500-2000nm wavelength range, the spectral resolution
is between ∼0.0004 and 0.004nm, and the absolute radiometric
uncertainty is mainly less than 1%. The agreement with the TSIS-1 HSRS
reference spectrum is excellent since the difference between SOLAR-HRS
and TSIS-1 HSRS is close to 3% between 500 and 2000nm. In terms of the
Fraunhofer central line positions and shapes (equivalent widths and
central line depths), the relative difference between SOLAR-HRS and
TSIS-1 HSRS is very weak in the 500-2000nm wavelength range. For the
MicroCarb observation bands (B1 to B4), the SOLAR-HRS disk-integrated
spectrum partially meets MicroCarb's scientific requirements
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 240 9 High resolution Solar Spectra
sp/* . 9 Individual spectra
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See also:
http://bdap.ipsl.fr/voscat_en/solarspectra.html : Spectra Home Page
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 46 A46 --- Set Data set name
47 A1 --- n_Set [*] Note on Set (1)
48- 82 A35 --- Type Data type
84- 88 F5.1 nm lambdamin Wavelength coverage
89 A1 --- --- [-]
90- 95 F6.1 nm lambdamax Wavelength coverage
97-179 A83 --- SpRes Spectral resolution
181-187 A7 --- Sampling Sampling
189-240 A52 --- FileName Name of spectrum file in subdirectory sp
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Note (1): For SOLAR-HRS solar positions,
mu=1.0,0.9,0.8,0.7,0.6,0.5,0.4,0.3,0.2,0.1,0.05
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History:
Copied at http://bdap.ipsl.fr/voscat_en/solarspectra.html
(End) Patricia Vannier [CDS] 05-Sep-2023