13 research outputs found
A Coherence-Based Approach for Tracking Waves in the Solar Corona
We consider the problem of automatically (and robustly) isolating and
extracting information about waves and oscillations observed in EUV image
sequences of the solar corona with a view to near real-time application to data
from the Atmospheric Imaging Array (AIA) on the Solar Dynamics Observatory
(SDO). We find that a simple coherence / travel-time based approach detects and
provides a wealth of information on transverse and longitudinal wave phenomena
in the test sequences provided by the Transition Region and Coronal Explorer
(TRACE). The results of the search are "pruned" (based on diagnostic errors) to
minimize false-detections such that the remainder provides robust measurements
of waves in the solar corona, with the calculated propagation speed allowing
automated distinction between various wave modes. In this paper we discuss the
technique, present results on the TRACE test sequences, and describe how our
method can be used to automatically process the enormous flow of data
(~1Tb/day) that will be provided by SDO/AIA after launch in late 2008.Comment: 34 pages, 16 figures - in press Solar Physic
Siberian Radioheliograph: first results
Regular observations of active processes in the solar atmosphere have been started using the first stage of the multiwave Siberian Radioheliograph (SRH), a T-shaped 48-antenna array with a 4â8 GHz operating frequency range and a 10 MHz instantaneous receiving band. Antennas are mounted on the central antenna posts of the Siberian Solar Radio Telescope. The maximum baseline is 107.4 m, and the angular resolution is up to 70. We present examples of observations of the solar disk at different frequencies, ânegativeâ bursts, and solar flares. The sensitivity to compact sources reaches 0.01 solar flux units (â10â4 of the total solar flux) with an accumulation time of about 0.3 s. The high sensitivity of SRH enables monitoring of solar activity and allows studying active processes from characteristics of their microwave emission, including faint events, which could not be detected previously