Solar X-ray flares and ionospheric sudden phase anomalies relationship: A solar cycle phase dependence
dc.contributor.author | Pacini A.A. | |
dc.contributor.author | Raulin J.-P. | |
dc.date.accessioned | 2024-03-13T01:42:02Z | |
dc.date.available | 2024-03-13T01:42:02Z | |
dc.date.issued | 2006 | |
dc.description.abstract | We investigate the relation between sudden phase anomaly (SPA) amplitudes (Δφ) and solar X-ray flares importance and study if it has a solar activity cycle dependence. We find a very significant correlation between Δφ and the X-ray fluences, Fx (time-integrated photon fluxes) in the range 0.5-2 Å. Compared with earlier works, the improvements of the Δφ versus FX relation allow us to study separately solar events as a function of their occurrence in the solar activity cycle, and we find that the Δφ versus FX relation is different depending on the epoch within the solar cycle. In particular, a minimum X-ray fluence of 2.5 × 10-6 J m-2 is needed during solar activity minimum to trigger a SPA, while during solar maximum, 7.0 × 10-6 J m-2 is required. Similarly, a solar flare will producer SPA during solar minimum that is greater by ∼2.6° M m -1 than would a flare of the same size during solar maximum. These results confirm recent findings about the dependence with the solar activity of the ionospheric undisturbed D region sensitivity. A possible consequence would be the monitoring of the long-term solar irradiance, which maintains the D region, through measurements of VLF wave propagation properties. Copyright 2006 by the American Geophysical Union. | |
dc.description.issuenumber | 9 | |
dc.description.volume | 111 | |
dc.identifier.doi | 10.1029/2006JA011613 | |
dc.identifier.issn | 2169-9402 | |
dc.identifier.uri | https://dspace.mackenzie.br/handle/10899/37764 | |
dc.relation.ispartof | Journal of Geophysical Research: Space Physics | |
dc.rights | Acesso Restrito | |
dc.title | Solar X-ray flares and ionospheric sudden phase anomalies relationship: A solar cycle phase dependence | |
dc.type | Artigo | |
local.scopus.citations | 46 | |
local.scopus.eid | 2-s2.0-33947541159 | |
local.scopus.updated | 2024-05-01 | |
local.scopus.url | https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=33947541159&origin=inward |