Abstract Details
| Name: Divya Oberoi Affiliation: NCRA-TIFR Conference ID: ASI2015_484 Title : First Murchison Widefield Array Observations of a Type II Solar Radio Burst Authors and Co-Authors : Iver H. Cairns (2), Colin J. Lonsdale (3), J. M. Schmidt (2), J. Harding (2), J. Morgan (4), S. White (5) and The MWA Collaboration 2 - University of Sydney, Sydney, Australia 3 - MIT Haystack Observatory, MA, USA 4 - Curtin University, Perth, Australia 5 - Kirtland Air Force Base, NM, USA Abstract Type : Invited Abstract Category : Sun and the Solar System Abstract : The Murchison Widefield Array (MWA) is the low frequency (80-300 MHz) SKA precursor located at the site chosen for the SKA in the radio quiet Western Australian Outback and commenced formal observing in mid 2013. Solar and Heliospheric science are amongst the key science objectives of the MWA. Its spectroscopic imaging capability with much higher imaging fidelity than the earlier generation of instruments make it especially well suited for following dynamic in solar radio images simultaneously along time, frequency and polarization axes. MWA detected its first type II solar radio burst on 7 September 2014 during the period 0205 – 0215 UT. One of the SHI Group’s primary targets, type II solar radio bursts are often produced upstream of shock waves driven by coronal mass ejections (CMEs) in the solar corona and solar wind. Both fundamental and harmonic emission bands were observed for this type II, both with split-band fine structures. MWA, Learmonth, and Yunnan data show the burst from 300 MHz (harmonic) to 30 MHz (fundamental). The burst did not extend below 15 MHz according to Wind spacecraft data, thereby being purely a coronal type II. A strong CME observed by the SDO and STEREO B spacecraft is plausibly associated with the type II burst. We present these data, emphasizing the unique time-varying radio source locations observed by MWA and the detailed dynamic spectra measured by MWA, Learmonth, and Yunnan. We also present initial theoretical predictions for the radio dynamic spectrum and source locations, produced by Schmidt & Cairns’s combination of a detailed radio theory with 3D MHD simulations (using the University of Michigan BATS-R-US code) of the event-specific corona and CME. |