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Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.39 [2010] >
IJRSP Vol.39(4) [August 2010] >
| Title: | Preliminary reverse impulse in SC (Y) at off - equatorial stations in India |
| Authors: | Rastogi, R G
Ahmed, K |
| Keywords: | Preliminary reverse impulse (PRI)
Sudden storm commencement (SSC)
Geomagnetic eastward component |
| Issue Date: | Aug-2010 |
| Publisher: | CSIR |
| PACS No.: | 94.20.Vv; 94.30.vf; 96.60.Vg |
| Abstract: |
The
storm sudden commencement (SSC) at 2345 hrs UT on 24 September 1998, occurring
at around local sunrise for Indian stations had produced uniquely two–step
impulses on the H magnetogram at all stations. The amplitude ∆H had increased
progressively from Trivandrum
to Gulmarg, unlike the characteristic of the day time equatorial enhancement of
SC (H). The solar wind parameters too showed abnormal variations during the
period of SC.
The magnetogram trace for
declination (or eastward field Y) recorded a preliminary reverse impulse (PRI)
close to the latitude of Sq focus at stations Gulmarg, Ujjain, Nagpur and
Shillong. The PRI was absent in SC (Y) at equatorial stations Trivandrum and
Pondicherry. This observations show a new complex relationship between the
ionospheric dynamo and magnetospheric dawn / dusk electric field with the
equatorial geomagnetic field around sunrise. |
| Page(s): | 203-207 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-105X (Online); 0367-8393 (Print) |
| Source: | IJRSP Vol.39(4) [August 2010]
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