High-Speed x-ray Jets Associated with the 18 June 1999 Limb Flares     

Kim  Yeon-Han  Kim  Kap-Sung  Jang  Minhwan 《Solar physics》2001,203(2):371-379

Peculiar high-speed X-ray jets associated with the 18 June 1999 limb flares have directly been observed with the soft X-ray Telescope (SXT) aboard Yohkoh. The jets have a much shorter lifetime (within 200 s) and a much larger velocity (∼ 1700 km s⁻¹) than the previously reported jets. Judged from their large velocity, the kinetic energy of the jets is approximately one order of magnitude larger than the thermal energy content, which is far different from the jets previously reported by other researchers. Here we present the preliminary results and discuss the particular features of the jets. Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1013324126229  相似文献   

Velocities and Temperatures of an Ellerman Bomb and Its Associated Features     

Heesu Yang  Jongchul Chae  Eun-Kyung Lim  Hyungmin Park  Kyuhyoun Cho  Ram Ajor Maurya  Donguk Song  Yeon-Han Kim  Philip R. Goode 《Solar physics》2013,288(1):39-53

We investigated the velocity and temperature characteristics of an Ellerman bomb (EB) and its associated features based on observations made with the Fast Imaging Solar Spectrograph (FISS) and a broadband TiO filter of the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. In the TiO images of the photospheric level, we found a granular cell expanding in two opposite directions near the site of the EB. When one end of this granule reached the EB site, the transverse speed of the tip of the expanding granule rapidly decreased and the EB brightened. The wings of the Hα profile of the EB indicated that the EB was blueshifted up to 7 km?s^?1. About 260 s after the EB brightening, a surge was seen in absorption and varied from a blueshift of 20 km?s^?1 to a redshift of 40 km?s^?1 seen in the Hα and Ca ii 8542 Å lines. From the Doppler absorption width of the two lines determined by applying the cloud model, we estimated the mean temperature of the surge material to be about 29000 K and the mean speed of nonthermal motion to be about 11 km?s^?1. We discuss the physical implications of our results in terms of magnetic reconnection and processes related to it.  相似文献   

Temperature of Solar Prominences Obtained with the Fast Imaging Solar Spectrograph on the 1.6 m New Solar Telescope at the Big Bear Solar Observatory     

Hyungmin Park  Jongchul Chae  Donguk Song  Ram Ajor Maurya  Heesu Yang  Young-Deuk Park  Bi-Ho Jang  Jakyoung Nah  Kyung-Suk Cho  Yeon-Han Kim  Kwangsu Ahn  Wenda Cao  Philip R. Goode 《Solar physics》2013,288(1):105-116

We observed solar prominences with the Fast Imaging Solar Spectrograph (FISS) at the Big Bear Solar Observatory on 30 June 2010 and 15 August 2011. To determine the temperature of the prominence material, we applied a nonlinear least-squares fitting of the radiative transfer model. From the Doppler broadening of the Hα and Ca ii lines, we determined the temperature and nonthermal velocity separately. The ranges of temperature and nonthermal velocity were 4000?–?20?000 K and 4?–?11 km?s^?1. We also found that the temperature varied much from point to point within one prominence.  相似文献   

The global temperature anomaly and solar North-South asymmetry   总被引：1，自引：0，他引：1  

Il-Hyun Cho  Young-Sil Kwak  Heon-Young Chang  Kyung-Suk Cho  Yeon-Han Kim  Young-Deuk Park 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(3):253-257

We investigate whether the global temperature anomaly is associated with the solar North-South asymmetry using data archived approximately for five solar cycles. We are motivated by both the accumulating evidence for the connection of Galactic cosmic-rays (GCRs) to the cloud coverage and recent finding of the association of GCR influx and the solar North-South asymmetry. We have analyzed the data of the observed sunspot, the GCR influx observed at the Moscow station, and the global temperature anomaly. We have found that the mean global temperature anomaly is systematically smaller (??0.56 in the unit of its standard deviation) during the period when the solar northern hemisphere is more active than the solar southern hemisphere. The difference in the mean value of the global temperature anomaly for the two data sets sub-sampled according to the solar North-South asymmetry is large and statistically significant. We suggest the solar North-South asymmetry is related to the global temperature anomaly through modulating the amount of GCR influx. Finally, we conclude by discussing its implications on a climate model and a direction of future work.  相似文献