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| Titel |
Characterization of X-ray and Type III radio bursts during solar cycle 24 for short-term warning of solar energetic particle events |
| VerfasserIn |
Tommaso Alberti, Monica Laurenza, Marisa Storini, Fabio Lepreti, Edward W. Cliver |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250133933
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| Publikation (Nr.) |
 EGU/EGU2016-14599.pdf |
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| Zusammenfassung |
| The empirical model developed by Laurenza et al. (2009), based on data from 1995 to 2005,
can provide short-term warnings of solar energetic proton (SEP) events that meet or exceed
the Space Weather Prediction Center threshold of J (≥ 10MeV ) = 10 p cm−2 s−1 sr−1,
within 10 minutes after the maximum of the associated soft X-ray flare. The ≥ M2 X-ray and
type III bursts occurred in the period 2006 - 2014 were used to compute the parameters of the
model, i.e. the time-integrated soft X-ray intensity and time-integrated intensity
of type III radio emission at about 1 MHz. The probability distribution functions
associated with both parameters were derived. It was found that both the occurrence
and the fluence of X-ray bursts is noticeably reduced in solar cycle 24 (35% and
30%, respectively, compared to solar cycle 23). The radio fluence of type III bursts
associated to the considered X-ray events was lower of about 30% as well. Moreover, in
order to test the accuracy of the model, the probability of detection (POD) and the
False Alarm Rate (FAR) were evaluated by using the new database. The obtained
verification measures show a good performance of the model: POD= 59% and
FAR= 30%, which are, respectively, comparable and even lower with respect to
those obtained from the datset on which the model was developed. Moreover, the
performance is very high when major SEP events, having a peak flux ≥ 100 pfu, are
considered (POD=79%, FAR=5%), i. e., for the most hazardous Space Weather
conditions. Finally, the median warning time (as computed by Nunez (2011)) was
estimated to be of about 11 h, highly exceeding that obtained through other competing
techniques.
References
[1] Laurenza, M., E. W. Cliver, J. Hewitt, M. Storini, A. Ling, C. C. Balch, and
M. L. Kaiser (2009), Space Weather, 7, S04008, doi:10.1029/2007SW000379.
[2] Núñez, M. (2011), Predicting solar energetic proton events (E > 10 MeV),
Space Weather, 9, S07003, doi:10.1029/2010SW000640. |
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