J/ApJS/255/16 Quiet-Sun MgII h & k line profiles from IRIS (Gunar+, 2021)
Quiet-Sun MgII h and k line profiles derived from IRIS full-Sun mosaics.
I. Reference profiles and center-to-limb variation.
Gunar S., Koza J., Schwartz P., Heinzel P., Liu W.
<Astrophys. J. Suppl. Ser., 255, 16-16 (2021)>
=2021ApJS..255...16G 2021ApJS..255...16G (SIMBAD/NED BibCode)
ADC_Keywords: Sun; Ultraviolet
Keywords: Solar ultraviolet emission; Solar atmosphere; Limb darkening
Limb brightening; Solar spectral irradiance
Abstract:
We derived high-precision reference profiles of the MgII h and k lines
that represent the quiet Sun during a minimum of the solar activity.
To do so, we used the broad catalog of full-Sun mosaics obtained by
the Interface Region Imaging Spectrograph (IRIS). To minimize the
influence of the local variations due to the on-disk solar features
and to achieve low levels of uncertainties, we used 12 IRIS full-Sun
mosaics without sunspots or other significant signs of solar activity.
These mosaics were obtained between 2019 April and 2020 September in
the near-ultraviolet spectral range. In this paper, we present the
disk-averaged reference profiles of MgII h and MgII k lines, together
with a series of reference profiles spanning the distance between the
disk center and the solar limb. These series of profiles offer a
detailed representation of the center-to-limb variation of both MgII h
and MgII k lines. The reference MgII h and k line profiles provided in
this paper can be used as the incident radiation boundary condition
for radiative-transfer modeling of prominences, spicules, and other
coronal and chromospheric structures.
Description:
Since its launch, the Interface Region Imaging Spectrograph (IRIS)
commenced a quasi-regular acquisition of maps of the entire solar disk
in both NUV and FUV spectral ranges.
At the time of writing, the archive of the IRIS full-Sun mosaics
contained 91 observations spanning the period from 2013 September 30
to 2020 October 19 which cover two spectral windows of ±1.75Å
centered at 2803.53Å (MgII h) and 2796.35Å (MgII k).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 76 101 MgII k reference profiles in individual zones a-j
table4.dat 76 101 MgII h reference profiles in individual zones a-j
table5.dat 28 101 The disk-averaged MgII k reference profile
table6.dat 28 101 The disk-averaged MgII h reference profile
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See also:
J/A+A/423/1109 : Center-to-limb variation of quiet Sun (Allende+, 2004)
J/A+A/432/1063 : Analysis of inner solar corona in EUV (Lanzafame+, 2005)
J/ApJS/213/11 : UV spectrum of the quiet Sun above the limb (Warren+, 2014)
J/A+A/624/A36 : EUV irradiances of the quiet Sun (Del Zanna, 2019)
J/A+A/644/A109 : Quiet-sun hydrogen Lyman-alpha line profile (Gunar+, 2020)
J/ApJ/897/L10 : Disturbance storm time index (Hayakawa+, 2020)
http://iris.lmsal.com/mosaic.html : IRIS full-disk mosaics data
Byte-by-byte Description of file: table[34].dat
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Bytes Format Units Label Explanations
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1- 6 F6.3 0.1nm delLam [-1.75/1.75] Wavelength separation,
Δλ in Å (1)
8- 10 I3 10W/m2/sr/nm aI [32/316] Zone a MgII specific intensity (2)
12- 13 I2 % e_aI [2/14] Percent uncertainty in aI
15- 17 I3 10W/m2/sr/nm bI [31/311] Zone b MgII specific intensity (2)
19- 20 I2 % e_bI [2/14] Percent uncertainty in bI
22- 24 I3 10W/m2/sr/nm cI [30/306] Zone c MgII specific intensity (2)
26- 27 I2 % e_cI [2/14] Percent uncertainty in cI
29- 31 I3 10W/m2/sr/nm dI [29/302] Zone d MgII specific intensity (2)
33- 34 I2 % e_dI [2/15] Percent uncertainty in dI
36- 38 I3 10W/m2/sr/nm eI [28/297] Zone e MgII specific intensity (2)
40- 41 I2 % e_eI [2/15] Percent uncertainty in eI
43- 45 I3 10W/m2/sr/nm fI [26/290] Zone f MgII specific intensity (2)
47- 48 I2 % e_fI [2/16] Percent uncertainty in fI
50- 52 I3 10W/m2/sr/nm gI [25/281] Zone g MgII specific intensity (2)
54- 55 I2 % e_gI [2/17] Percent uncertainty in gI
57- 59 I3 10W/m2/sr/nm hI [23/268] Zone h MgII specific intensity (2)
61- 62 I2 % e_hI [2/18] Percent uncertainty in hI
64- 66 I3 10W/m2/sr/nm iI [21/250] Zone i MgII specific intensity (2)
68- 69 I2 % e_iI [2/20] Percent uncertainty in iI
71- 73 I3 10W/m2/sr/nm jI [17/212] Zone j MgII specific intensity (2)
75- 76 I2 % e_jI [3/24] Percent uncertainty in jI
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Note (1): From the rest wavelength of the MgII k (2796.35Å; Table 3) or
MgII h (2803.53Å; Table 4) line in units of Angstroms.
Note (2): In units of W/m2/sr/Angstrom.
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Byte-by-byte Description of file: table[56].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.3 0.1nm delLam [-1.75/1.75] Wavelength separation;
Δλ in Å (1)
8- 10 I3 10W/m2/sr/nm I1 [26/280] Specific intensity (2)
12- 19 E8.2 mW/m2/sr/Hz I2 [6.8e-8/7.4e-7] Specific intensity;
in erg/s/cm2/sr/Hz units
21- 25 F5.2 cW/m2/nm Ee [1.79/19.05] Spectral irradiance
27- 28 I2 % sigma [2/16] Percent uncertainty in
intensity & irradiance
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Note (1): From the rest wavelength of the MgII k (2796.35Å; Table 5) or
MgII h (2803.53Å; Table 6) line in units of Angstroms.
Note (2): In units of W/m2/sr/Angstrom.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 26-Oct-2021