Spectroscopic Diagnostics of the Non-Maxwellian kappa-distributions Using SDO/EVE Observations of the 2012 March 7 X-class Flare

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F18%3A00494688" target="_blank" >RIV/67985815:_____/18:00494688 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.3847/1538-4357/aaa426" target="_blank" >http://dx.doi.org/10.3847/1538-4357/aaa426</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/1538-4357/aaa426" target="_blank" >10.3847/1538-4357/aaa426</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spectroscopic Diagnostics of the Non-Maxwellian kappa-distributions Using SDO/EVE Observations of the 2012 March 7 X-class Flare

Popis výsledku v původním jazyce

Spectroscopic observations made by the Extreme Ultraviolet Variability Experiment (EVE) on board the Solar Dynamics Observatory (SDO) during the 2012 March 7 X5.4-class flare (SOL2012-03-07T00: 07) are analyzed for signatures of the non-Maxwellian kappa-distributions. Observed spectra were averaged over 1 minute to increase photon statistics in weaker lines and the pre-flare spectrum was subtracted. Synthetic line intensities for the.distributions are calculated using the KAPPA database. We find strong departures (kappa less than or similar to 2) during the early and impulsive phases of the flare, with subsequent thermalization of the flare plasma during the gradual phase. If the temperatures are diagnosed from a single line ratio, the results are strongly dependent on the value of kappa. For kappa =. 2, we find temperatures about a factor of two higher than the commonly used Maxwellian ones. The non-Maxwellian effects could also cause the temperatures diagnosed from line ratios and from the ratio of GOES X-ray channels to be different. Multithermal analysis reveals the plasma to be strongly multithermal at all times with flat DEMs. For lower kappa, the DEM kappa are shifted toward higher temperatures. The only parameter that is nearly independent of. is electron density, where we find log n(e) [cm(-3)]) approximate to 11.5 almost independently of time. We conclude that the nonMaxwellian effects are important and should be taken into account when analyzing solar flare observations, including spectroscopic and imaging ones.

Název v anglickém jazyce

Spectroscopic Diagnostics of the Non-Maxwellian kappa-distributions Using SDO/EVE Observations of the 2012 March 7 X-class Flare

Popis výsledku anglicky

Spectroscopic observations made by the Extreme Ultraviolet Variability Experiment (EVE) on board the Solar Dynamics Observatory (SDO) during the 2012 March 7 X5.4-class flare (SOL2012-03-07T00: 07) are analyzed for signatures of the non-Maxwellian kappa-distributions. Observed spectra were averaged over 1 minute to increase photon statistics in weaker lines and the pre-flare spectrum was subtracted. Synthetic line intensities for the.distributions are calculated using the KAPPA database. We find strong departures (kappa less than or similar to 2) during the early and impulsive phases of the flare, with subsequent thermalization of the flare plasma during the gradual phase. If the temperatures are diagnosed from a single line ratio, the results are strongly dependent on the value of kappa. For kappa =. 2, we find temperatures about a factor of two higher than the commonly used Maxwellian ones. The non-Maxwellian effects could also cause the temperatures diagnosed from line ratios and from the ratio of GOES X-ray channels to be different. Multithermal analysis reveals the plasma to be strongly multithermal at all times with flat DEMs. For lower kappa, the DEM kappa are shifted toward higher temperatures. The only parameter that is nearly independent of. is electron density, where we find log n(e) [cm(-3)]) approximate to 11.5 almost independently of time. We conclude that the nonMaxwellian effects are important and should be taken into account when analyzing solar flare observations, including spectroscopic and imaging ones.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astrophysical Journal

ISSN

1538-4357

e-ISSN

—

Svazek periodika

853

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

—

Kód UT WoS článku

000424011300019

EID výsledku v databázi Scopus

2-s2.0-85041917126