Pregled bibliografske jedinice broj: 237769
Shrinking and Cooling of Flare Loops in a Two-Ribbon Flare
Shrinking and Cooling of Flare Loops in a Two-Ribbon Flare // Solar Physics, 234 (2006), 273-299 (međunarodna recenzija, članak, znanstveni)
CROSBI ID: 237769 Za ispravke kontaktirajte CROSBI podršku putem web obrasca
Naslov
Shrinking and Cooling of Flare Loops in a Two-Ribbon Flare
Autori
Vršnak, Bojan ; Temmer, Manuela ; Veronig, Astrid ; Karlicky, Marian ; Lin, Jun
Izvornik
Solar Physics (0038-0938) 234
(2006);
273-299
Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni
Ključne riječi
Sun - flares
(Sunčevi bljeskovi)
Sažetak
We analyze the evolution of the flare/postflare-loop system in the two-ribbon flare of November 3, 2003, utilizing multi-wavelength observations that cover the temperature range from several tens of MK down to 10^4 K. A non-uniform growth of the loop system enables us to identify analogous patterns in the height– time, h(t), curves measured at different temperatures. The “ knees, ” “ plateaus, ” and “ bends” in a higher-temperature curve appear after a certain time delay at lower heights in a lower-temperature curve.We interpret such a shifted replication as a track of a given set of loops (reconnected field lines) while shrinking and cooling after being released from the reconnection site. Measurements of the height/time shifts between h(t) curves of different temperatures provide a simultaneous estimate of the shrinkage speed and cooling rate in a given temperature domain, for a period of almost ten hours after the flare impulsive phase. From the analysis we find the following: (a) Loop shrinkage is faster at higher temperatures – in the first hour of the loop-system growth, the shrinkage velocity at 5MK is 20 – 30 km s− 1, whereas at 1MK it amounts to 5 kms− 1 ; (b) Shrinking becomes slower as the flare decays – ten hours after the impulsive phase, the shrinkage velocity at 5MK becomes 5 kms− 1 ; (c) The cooling rate decreases as the flare decays – in the 5MK range it is 1MKmin− 1 in the first hour of the loop-system growth, whereas ten hours later it decreases to 0.2MKmin− 1 ; (d) During the initial phase of the loop-system growth, the cooling rate is larger at higher temperatures, whereas in the late phases the cooling rate apparently does not depend on the temperature ; (e) A more detailed analysis of shrinking/cooling around one hour after the impulsive phase reveals a deceleration of the loop shrinkage, amounting to ¯ ; ; a ≈ 10ms− 2 in the T < 5MK range ; (f) In the same interval, conductive cooling dominates down to T ≈ 3 MK, whereas radiation becomes dominant below T ≈ 2 MK ; (g) A few hours after the impulsive phase, radiation becomes dominant across the whole T < 5MK range. These findings are compared with results of previous studies and discussed in the framework of relevant models.
Izvorni jezik
Engleski
Znanstvena područja
Fizika
POVEZANOST RADA
Citiraj ovu publikaciju:
Časopis indeksira:
- Current Contents Connect (CCC)
- Web of Science Core Collection (WoSCC)
- Science Citation Index Expanded (SCI-EXP)
- SCI-EXP, SSCI i/ili A&HCI
- Scopus
Uključenost u ostale bibliografske baze podataka::
- NASA-ADS
