J/A+A/640/A17 CR Ground Level Enhancements spectra (IGLED) (Usoskin+, 2020)
Revisited GLE database: Fluences of solar energetic particles as measured by
the neutron-monitor network since 1956.
Usoskin I.G., Koldobskiy S., Kovaltsov G.A., Gil A., Usoskina I.,
Willamo T., Ibragimov A.
<Astron. Astrophys. 640, A17 (2020)>
=2020A&A...640A..17U 2020A&A...640A..17U (SIMBAD/NED BibCode)
ADC_Keywords: Sun
Keywords: Sun: particle emission - catalogs - Sun: flares -
solar-terrestrial relations
Abstract:
Continuous measurements of ground-based neutron monitors (NMs) form
the main data source to study high-energy/high-intensity solar
energetic particle (SEP) events, called ground-level enhancements
(GLEs). All available data are collected in the International GLE
Database (IGLED, http://gle.oulu.fi), which provides formal NM
count-rate increases above the constant pre-increase level due to
galactic cosmic rays (GCR). This dataset is used to reconstruct energy
spectra of GLE events. However, the assumption of the constant GCR
background level throughout GLE events is often invalid. Here we made
a major revision of the IGLED dataset and provided a dataset of
detrended NM count-rate increases accounting for the variable GCR
background.
The formal GLE count-rate increases were corrected for the variable
GCR background which may vary significantly during GLE events. The
corresponding integral omnidirectional fluences of SEPs were
reconstructed for all GLEs with the sufficient strength from the
detrended data using the "effective rigidity" method.
The database of detrended NM count-rate has been reset for all GLE
events since 1956. The integral omnidirectional fluences have been
estimated for all the GLE evens and parameterized for sufficiently
strong ones by the modified Ellison-Ramaty spectral shape.
The IGLED has been revisited to account for the variable GCR
background. Integral omnidirectional fluences reconstructed for most
of GLE events, have benn added to IGLED. This forms a basis for more
precise studies of parameters of SEP events and, thus, for Solar and
space physics.
Description:
Files (names as 'GLEXX_spec.dat') contain, for each GLE event numbered
as XX, name [Name], vertical geomagnetic cutoff rigidity [Pc], nominal
atmospheric depth [h], the integral GLE intensity [X], reconstructed
effective rigidity [Re] along with its full-range lower [e_Re] and
upper [E_Re] uncertainties, omni-directional integral fluence F(>Re)
[F] along with its full-range lower [e_F] and upper [E_F]
uncertainties, for all NMs with available data. F=0 implies that only
the upper limit on F(>Re) can be provided.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 32 56 List of spectra
sp/* . 58 Individual spectra
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See also:
http://gle.oulu.fi : IGLED, International GLE Database Home Page
Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- GLE GLE event identification
8- 17 A10 "date" Obs.date Observation date
19- 32 A14 --- FileName Name of the spectrum file in subdirectory sp
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 4 A4 --- Name Standard neutron monitor (NM) name
6- 10 F5.2 GV Pc Neutron monitor's effective geomagnetic cutoff
rigidity
12- 15 I4 g/cm2 h Neutron monitor's atmospheric depth
17- 22 F6.1 %.h X Integral GLE intensity
24- 28 F5.2 GV Re Effective rigidity
30- 33 F4.2 GV E_Re Full-range upper uncertainty of Re
35- 38 F4.2 GV e_Re Full-range lower uncertainty of Re
40- 47 E8.3 cm-2 F Omnidirectional integral fluence
49- 56 E8.3 cm-2 E_F Full-range upper uncertainty of F
58- 65 E8.3 cm-2 e_F Full-range lower uncertainty of F
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Acknowledgements:
Ilya Usoskin, ilya.usoskin[at]oulu.fi
(End) Patricia Vannier [CDS] 03-Jun-2020