J/A+A/665/A65 1984-2019 annual integral solar proton fluences (Raukunen+, 2022)
Annual integral solar proton fluences for 1984-2019.
Raukunen O., Usoskin, I., Koldobskiy S., Kovaltsov G., Vainio R.
<Astron. Astrophys. 665, A65 (2022)>
=2022A&A...665A..65R 2022A&A...665A..65R (SIMBAD/NED BibCode)
ADC_Keywords: Sun
Keywords: Sun: particle emission - Sun: flares - Sun: activity -
solar-terrestrial relations
Abstract:
Long-term fluxes or integral fluences of solar energetic particle
(SEP) and their variability within and beyond the 11-year solar cycle
makes an important information for Space Physics. However, large
uncertainties exist in evaluation of the average SEP fluxes or
fluences over the last decades as assessed by different methods and
from different datasets. Here we re-visit the derivation of annual
integral SEP fluences from available data based on in-situ
measurements since 1984.
We have reconstructed a full time series of integral SEP fluxes above
10, 30, 60, 100 and 200MeV for the period from 1984 to 2019 using
observations performed by the GOES satellites. Intercalibration of the
fluxes was performed via a linear relation between overlapping pairs
of observations in order to obtain a uniform dataset. Galactic cosmic
ray (GCR) background subtraction and identification of SEP event
periods was carefully performed, allowing for precise calculation of
annual SEP fluences.
Annual integral fluences of SEPs with energies above 10, 30, 60, 100
and 200MeV have been calculated for the period from 1984 to 2019
(solar cycles 22-24) along with uncertainties. It is shown that solar
cycle 24 was significantly (factor of 5-8) weaker in the SEP fluence
than the preceding cycles 22 and 23. The cumulative occurrence
probability of years with the fluence above a given value is found to
be perfectly described by the Weibull distribution. This can be used
as a projection for the occurrence of solar extreme eruptive events on
the secular time scales. In addition to the annual fluences, a dataset
containing hourly integral SEP fluxes is available at the CDS.
Description:
The file hourly.dat contains the hourly integral proton fluxes (in
units of cm^-2 sr^-2 s^-1) observed by the GOES satellites during
1984-2019 above 5 threshold energies (10MeV, 30MeV, 60MeV, 100 MeV
and 200 MeV), along with their error estimates and flags indicating
whether or not the datapoint belongs to an SEP event.
The file annual.dat (Table D.1 in the article) contains the annual
integral proton fluences for 1984-2019 above 5 threshold energies
(10MeV, 30MeV, 60MeV, 100MeV and 200MeV), along with their error
estimates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hourly.dat 134 315576 Hourly integral Fluxes, error estimates and
SEP event flags
annual.dat 104 36 Annual integral fluences and error estimates
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See also:
J/A+A/640/A17 : CR Ground Level Enhancements spectra (IGLED) (Usoskin+, 2020)
J/A+A/647/A132 : GLE integral intensities (Koldobskiy+, 2021)
Byte-by-byte Description of file: hourly.dat
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Bytes Format Units Label Explanations
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1- 23 A23 "datime" Time Timestamp (UTC) (YYYY-MM-DDThh:mm:ss.ssss)
24 A1 --- n_Time [Z] Z for UTC time as defined in the
ISO 8601 standard
26- 34 E9.3 1/cm2/sr/s Flux10 Proton flux above 10MeV
36- 44 E9.3 1/cm2/sr/s e_Flux10 Error estimate for flux above 10MeV
46 I1 --- ev10 [0/1] Boolean flag for SEP activity (10MeV)
48- 56 E9.3 1/cm2/sr/s Flux30 Proton flux above 30MeV
58- 66 E9.3 1/cm2/sr/s e_Flux30 Error estimate for flux above 30MeV
68 I1 --- ev30 [0/1] Boolean flag for SEP activity (30MeV)
70- 78 E9.3 1/cm2/sr/s Flux60 Proton flux above 60MeV
80- 88 E9.3 1/cm2/sr/s e_Flux60 Error estimate for flux above 60MeV
90 I1 --- ev60 [0/1] Boolean flag for SEP activity (60MeV)
92-100 E9.3 1/cm2/sr/s Flux100 Proton flux above 100MeV
102-110 E9.3 1/cm2/sr/s e_Flux100 Error estimate for flux above 100MeV
112 I1 --- ev100 [0/1] Boolean flag for SEP activity (100MeV)
114-122 E9.3 1/cm2/sr/s Flux200 Proton flux above 200MeV
124-132 E9.3 1/cm2/sr/s e_Flux200 Error estimate for flux above 200MeV
134 I1 --- ev200 [0/1] Boolean flag for SEP activity (200MeV)
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Byte-by-byte Description of file: annual.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Year Year
6- 14 E9.3 cm-2 F10 Proton fluence above 10MeV
16- 24 E9.3 cm-2 e_F10 Error estimate for fluence above 10MeV
26- 34 E9.3 cm-2 F30 Proton fluence above 30MeV
36- 44 E9.3 cm-2 e_F30 Error estimate for fluence above 30MeV
46- 54 E9.3 cm-2 F60 Proton fluence above 60MeV
56- 64 E9.3 cm-2 e_F60 Error estimate for fluence above 60MeV
66- 74 E9.3 cm-2 F100 Proton fluence above 100MeV
76- 84 E9.3 cm-2 e_F100 Error estimate for fluence above 100MeV
86- 94 E9.3 cm-2 F200 Proton fluence above 200MeV
96-104 E9.3 cm-2 e_F200 Error estimate for fluence above 200MeV
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Acknowledgements:
Osku Raukunen, oajrau(at)utu.fi
(End) Patricia Vannier [CDS] 01-Jul-2022