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Sunquakes (SQs) have been routinely observed in the solar photosphere, but it is only recently that signatures of these events have been detected in the chromosphere. We investigate whether signatures of SQs are common in Ultraviolet (UV) continua, which sample the solar plasma several hundred km above where SQs are typically detected. We analyse observations from the Solar Dynamics Observatorys Atmospheric Imaging Assembly (SDO/AIA) 1600 {AA} and 1700 {AA} passbands, for SQ signatures induced by the flares of Solar Cycle 24. We base our analysis on the 62 SQs detected in the recent statistical study presented by Sharykin & Zosovichev (2020). We find that 9 out of 62 SQ candidates produced a response that is clearly detected in running difference images from the AIA 1600 {AA} and 1700 {AA} channels. A binary frequency filter with a width of 2 mHz, centred on 6 mHz, was applied to the data. The first signature of each SQ was detected at distances between 5.2 Mm to 25.7 Mm from the associated flare ribbon. Time-distance and regression analysis allowed us to calculate the apparent transverse velocities of the SQs in the UV datasets and found maximum velocities as high as 41 km s-1, 87 Mm away from the SQ source. Our analysis shows that flare induced SQ signatures can be detected in the SDO/AIA 1600 {AA} and 1700 {AA} passbands, hinting at their presence in the lower chromosphere. There was no apparent correlation between GOES flare classification, and the appearance of the SQ at these heights.
During non-flaring times, the radio flux of the Sun at the wavelength of a few centimeters to several tens of centimeters mostly originates from the thermal bremsstrahlung emission, very similar to the EUV radiation. Owing to such a proximity, it is
We present an analysis of off-limb cool flare loops observed by SDO/AIA during the gradual phase of SOL2017-09-10T16:06 X8.2-class flare. In the EUV channels starting from the 335 {AA} one, cool loops appear as dark structures against the bright loop
We present analysis of C7.0 solar flare of Febrary 17, 2013, revealing a strong helioseismic response (sunquake) caused by a very compact impact in the photosphere. This is the weakest known C-class flare generating a sunquake event. To investigate p
Solar activity plays a quintessential role in influencing the interplanetary medium and space-weather around the Earth. Remote sensing instruments onboard heliophysics space missions provide a pool of information about the Suns activity via the measu
Mg II lines represent one of the strongest emissions from the chromospheric plasma during solar flares. In this article, we studied the Mg II lines observed during the X1 flare on March 29 2014 (SOL2014-03-29T17:48) by IRIS. IRIS detected large inten