Project Summary

Written by Ivica Skokic on .

"Millimeter and Submillimeter Observations of the solar Chromosphere with ALMA" (MSOC) is a four-year scientific project funded by the Croatian Science Foundation (project 7549). MSOC is a continuation of an ongoing solar research at the Hvar Observatory of the Faculty of Geodesy of the University of Zagreb.

MSOC was launched in October 2018 and aims to study the solar chromosphere, a dynamic interface layer of the Sun's atmosphere located between the photosphere and corona which plays an important role in transporting energy and matter into the outer layers. Full understanding of this layer is still elusive mostly due to the lack of suitable measurements and instruments. The main goal of the proposed research is to improve understanding of the solar chromosphere using the Atacama Large Millimeter/submillimeter Array (ALMA), a state-of-the-art astronomical interferometer, in combination with other ground and space based observatories. The project focuses on four main objectives: analysis of small and large scale solar structures observed by ALMA, modeling and interpretation of ALMA observations, and investigate their impact on other fields of solar physics.

Duration: 01.10.2018 - 30.09.2022

Total value: 886.795,85 HRK

For more information on MSOC, please contact the Project Leader.


First MSOC papers published

Written by Ivica Skokic on .

thumb Skokic diffusion paper 2019The first several papers related to the MSOC project were published recently. A paper by Selhorst et al. "Solar Polar Brightening and Radius at 100 and 230 GHz Observed by ALMA" studies polar brightenings of the Sun at radio frequencies using ALMA observations and comparing them to several theoretical models. A paper by Skokić and Brajša "ALMA Solar Ephemeris Generator" published in the Mining-geological-petroleum engineering bulletin describes an online software tool developed by the authors for easy preparation of solar observations with ALMA.

Vršnak studied the physical background of the evolution of a coronal magnetic flux rope embedded in the magnetic arcade during the gradual-rise pre-eruptive stage in a paper "Gradual Pre-eruptive Phase of Solar Coronal Eruptions" published in Frontiers in Astronomy and Space Sciences.

Two MSOC papers were published in the same issue of Astrophysical Journal. Vršnak et al. in "Heliospheric Evolution of Magnetic Clouds" present analysis of interplanetary evolution of 11 magnetic clouds. The analysis reveals that in a statistical sense, the expansion of the studied magnetic coluds (MCs) is compatible with self-similar behavior. However, individual events expose a large scatter of expansion rates, ranging from very weak to very strong expansion. Also, a discrepancy between the magnetic field decrease and the increase of the MC size was found, indicating that magnetic reconnection and geometrical deformations play a significant role in the MC evolution. In the paper "Turbulent Diffusion Derived from the Motions of SDO/AIA Coronal Bright Points" Skokić et al. study the motions of coronal bright points to infer the character and intensity of the solar diffusion processes. Results indicate subdiffusion on meso- to supergranular scales.