Thinkshop12

Solar Observations with ALMA

Miroslav Barta (Astronomical Institute ASCR)

Abstract. Solar observations belong to planned but not yet implemented capabilities of the ALMA observatory. They require specific regime because of many peculiarities of the objects at the Sun as the sources of radiation on mm/sub-mm wavelengths. Namely, the solar ALMA targets are – unlike their ‘more usual’ counterparts in the remote Universe – very intense, variable/dynamic on short timescales, having strong proper motion, and frequently quite extended. In order to cope with those issues and to allow for regular (science) solar observations starting already in Cycle 4 (call expected in Spring 2016!) a mixed team of experts has been established from all the three ALMA Regional Centers (EU ARC, NA ARC and EA ARC) to be working on this task. Because of its unique expertise in solar radio astronomy within the EU ARC, it was the Node in Ondrejov that has been mandated (by ESO/EU ARC) to work on implementation (commissioning) of the solar observing mode in frame of the project “Solar Research with ALMA”. Testing of suggested apporaches to the above mentioned issues represents an important part of work on the project. Therefore, two astronomers from the Czech EU ARC node, M. Barta and R. Brajsa, took part in the Solar ALMA Observing Campaign in December 2014 directly at ALMA OSF in Chile. The campaign was targetted namely at two topics: (i) Attenuation of too strong solar signal using SIS mixer detuning, and (ii) Fast-scanning of extended sources with the antennas of Total-Power (TP) sub-array. The talk shall sumarise objectives, work-course, preliminary results and follow-ups of the campaign.

Invited Talk