High time resolution observations of the solar flare Hα emission Original Research Article

We present here first results of a search for fast changes of the Hα emission arriving from individual kernels of the solar flares and correlated in time with X-ray flux variations recorded by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). During the 2003 observational season we collected four high time resolution Hα spectra-imaging data sets of flares with the Large Coronagraph, the Multi-channel Subtractive Double Pass Spectrograph and the Solar Eclipse Coronal Imaging System (SECIS) at Białków Observatory. The time resolution of the Hα data is 0.05 s, the spatial resolution is about 1 s of arc; each set of data consists of 10,000 images. We have found some instances of non-periodic, few-second-long variations of the Hα emission for the solar flare on July 16, 2003, which shows some time correlation with 12–25 keV X-ray fluxes as recorded by the RHESSI spacecraft.