Solar Vector Magnetograph: Instrument status and vector field measurements of non-flaring solar active regions

Abstract

The Solar Vector Magnetograph (SVM) of Udaipur Solar Observatory (USO) is an imaging polarimeter based on a tunable Fabry-Perot filter. In the present paper, the development efforts during phase-II of this instrument have been presented. These include: (i) installation of the instrument on a new robotic mount at the island site of USO; (ii) polarimetric calibrations of the instrument; and (iii) development of tools for performing data reduction and Stokes inversion. In particular, the Milne-Eddington inversion of polarized line profiles of the entire active region using parallel computing concept is described. Finally, few preliminary results regarding the vector magnetic field and other activity parameters of sunspots in non-flaring solar active regions are discussed. Such observations serve as a reference for comparison with flaring active regions.