Webinar

Study of solar active region heating using X-ray imaging spectroscopy

Speaker: P. S. Athiray (University of Alabama, Huntsville, US)

Date and time
Webinar link
Meeting ID: 846 9388 5820 Passcode: 051303
Venue
Auditorium

Abstract

Solar active regions are the brightest regions in the solar corona with a strong concentration of magnetic field, which are observed(believed) to be responsible for energy transportation and plasma heating in the solar corona, while maintaining the average coronal temperature at several MK above photosphere. Current observations indicate, ARs are comprised of loop structures with a wide range of temperatures spanning over spatial scales. One of the outstanding questions in solar physics is to observationally determine/constrain how the plasma is heated in the core of AR structures? Despite decades of observations in EUV and X-rays, the answer to this question is still elusive as existing solar observatories are sensitive for plasma cooling and could not provide discriminating observations. Therefore, next generation space instrumentation with high temperature diagnostics is the “smoking gun” observation required to constrain heating events.

In this talk, I will motivate the science investigation of solar active regions emphasizing the significance of high temperature diagnostics. I will present two novel instruments (FOXSI*, MaGIXS**), which are designed to provide high temperature diagnostics using direct X-ray imaging spectroscopy. FOXSI and MaGIXS are NASA-funded sounding rocket experiments, which are successfully flown and observed ARs. I will demonstrate my significant contribution to these instruments’ development involving X-ray optics testing, detector characterization, overall instrument calibration and flight data analysis. I will discuss interesting scientific observations/results of ARs from these two missions and establish my roles in the scientific analysis. At the end, I will motivate the need for future high-resolution X-ray instruments highlighting my involvement in some of the upcoming space missions.

* - Focusing Optics X-ray Solar Imager

** - Marshall Grazing Incidence X-ray Spectrometer

P. S. Athiray has completed his PhD from the Indian Space Research Organization, working with X-ray instruments aboard the Indian Moon missions Chandrayaan-1 and -2. Throughout his research he have been following a multi-pronged approach involving high energy instrumentation/calibration and scientific X-ray data analysis of the Sun and the Moon. His graduate research was on the study of lunar surface chemistry using X-ray fluorescence experiments and data from Chandrayaan-1 X-ray Spectrometer (C1XS). Athiray was involved in the early development and calibration of Chandrayaan-2 and have been a science team member. He joined as a post-doctoral associate at the University of Minnesota (UMN) with the FOXSI-3 sounding rocket team. He managed the detector team at UMN leading the hard X-ray detector tests, calibration and actively participated in the successful launch campaign of the FOXSI-3 instrument. Then he joined as a NASA Postdoctoral fellow at NASA Marshall Space Flight Center, as X-ray calibration lead for the rocket instrument MaGIXS, which was launched successfully in 2021. Athiray played several lead and support roles in testing, alignment and calibration of grazing incidence X-ray mirrors, X-ray grating and detectors. Currently he is leading the flight calibration and scientific data analysis of MaGIXS, which aims to constrain the frequency of heating in solar active regions. At present, he is a research scientist at the University of Alabama in Huntsville, working with NASA MSFC on several solar space missions. His current scientific research focuses on the study of plasma heating in solar active regions. He is the deputy instrument scientist for the upcoming MaGIXS-2 rocket flight (2023) and Project scientist for the cubesat mission CubIXSS (2024-2025).