Athena X-ray Advances: ASST & ACO Science Webinars

The next webinar of the “Athena X-ray Advances: ASST & ACO Science Webinars” will take place on the 26th of October at 15 CEST. Barbara de Marco will give the webinar entitled: A close up look at accreting BHs: the innermost regions as seen by Athena.

Abstract: observations of the close environments of accreting black holes (BH) are key to understand how these enigmatic engines can power some of the most luminous objects in the Universe.
As a matter of fact, it is right at the very inner, smallest regions around the BH that up to almost half of the accreting matter’s gravitational energy can be released. This is where we can seek answers to fundamental questions such as: How does strong gravity affect matter and radiation? How do BHs grow? How do BHs launch winds and jets?

For most objects in the sky, directly imaging these small regions is beyond the capabilities of current instruments, hence the need to rely on powerful indirect methods. Variable hard X-ray emission is one of the main outcomes of BH-accretion. While the cause of this variability is currently unknown, evidence exists for this emission to be produced via Comptonisation of the thermal disc photons by hot electrons in a plasma located close to the BH. The emitted, variable X-ray radiation illuminates the disc producing reprocessed emission, whose energy- and time-dependence can give important clues on the geometry of the innermost regions, and provide constraints on the BH mass and spin parameters.

In this webinar, I will describe some of the results obtained in recent years by combining the X-ray spectral and timing information from BH-accreting systems. I will finally discuss how the exploitation of Athena’s large collecting area and instrumental capabilities will allow for key advancements in this field.

The webinar connection details are: https://us06web.zoom.us/j/81316670753?pwd=eWJvbUdjQVVuSy9EQmhMU0N2Y25tUT09

Webinar ID: 813 1667 0753 (Passcode: 852869).

Further information, including the code of conduct, is accessible on the dedicated website.