Abstract
The Atacama Large millimetre/sub-millimetre Array (ALMA) has conducted regular high-cadence observation of the Sun since 2016, providing a new diagnostic tool for chromospheric observation. In this thesis, we aim to expend the possibilities for solar ALMA observations by achieving higher angular resolution and by simultaneously observing in two frequency (receiver) bands, which would enhance the study of oscillations and waves in the solar atmosphere. We use the Solar ALMA Simulator (SASim) and the Solar ALMA Pipeline (SoAP) to create ideal mock-up observations of ALMA for different array configurations, each possessing a different angular resolution. We tested the concept of splitting the ALMA array into two sub-arrays where each sub-array is assigned to observe one specific receiver band. We have found that it is possible to improve the angular resolution by using up to configuration 4 for Band 3 and up to configuration 5 for Band 6. We also detected 3 min oscillation period in the simulated Quiet Sun region using the sub-array method but we did not detected a shock wave with this method. Overall the sub-array observing mode is promising and further work would like lead to perfecting this novel method
Supervisor: Professor Sven Wedemeyer, Institute of Theoretical Astrophysics, UiO
Intern. assessor: Professor Boris V. Gudiksen, Institute of Theoretical Astrophysics, UiO
Extern. assessor: Senior Researcher Tobia Carozzi, Engineer at Onsala Space Observatory