X-RAY Spectroscopy of Outflows from accreting Black Holes; Retrospect of grating Spectrometers and Preparation for XRISM -

QUEST Center event
No
Speaker
Noa Keshet, Technion
Date
15/05/2024 - 15:30 - 14:00Add to Calendar 2024-05-15 14:00:00 2024-05-15 15:30:00 X-RAY Spectroscopy of Outflows from accreting Black Holes; Retrospect of grating Spectrometers and Preparation for XRISM - Outflows in black hole accreting systems are not yet fully understood.  Some of the open questions are what is the driving mechanism, where is the wind located, what are the abundances in the wind. These outflows are observed near black holes, from supermassive ones at the center of galaxies to galactic stellar mass X-ray binaries. Although these black holes differ by orders of magnitude in scale, there are similarities regarding the physical process of mass accretion and outflows. In this talk, I will report on Chandra/HETG grating observations over the past two decades characterizing similarities and differences between these systems. Starting with a sample of outflows in nine active galaxies (AGNs) for which we find a universal dependence of outflow column density, NH, on the ionization parameter, xi. I will demonstrate the importance of the XRISM/Resolve spectrometer in constraining the column density of the high-xi components better than HETG, and with much shorter observations. A sample of X-ray binary outflows is built in order to search for common behaviors and compare with the AGN sample. First, I will present the results of the richest outflow observed in an X-ray binary to date. When applying the same analysis to the outflow of the X-ray binary GRO J1655-40 we find a complex ionization structure of the wind, different in nature from that of AGNs. We use this structure to measure abundances of eighteen different elements in the wind, leading to inferences about the historical supernova explosion. The outflow is characterized by peaks in abundances of odd-Z elements, which have never before been observed in the X-ray, and originate in a massive type II supernova with supersolar metallicity.  Physics Building 202 Seminar Room 303 המחלקה לפיזיקה physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Physics Building 202 Seminar Room 303
Abstract

Outflows in black hole accreting systems are not yet fully understood.  Some of the open questions are what is the driving mechanism, where is the wind located, what are the abundances in the wind. These outflows are observed near black holes, from supermassive ones at the center of galaxies to galactic stellar mass X-ray binaries. Although these black holes differ by orders of magnitude in scale, there are similarities regarding the physical process of mass accretion and outflows. In this talk, I will report on Chandra/HETG grating observations over the past two decades characterizing similarities and differences between these systems. Starting with a sample of outflows in nine active galaxies (AGNs) for which we find a universal dependence of outflow column density, NH, on the ionization parameter, xi. I will demonstrate the importance of the XRISM/Resolve spectrometer in constraining the column density of the high-xi components better than HETG, and with much shorter observations. A sample of X-ray binary outflows is built in order to search for common behaviors and compare with the AGN sample. First, I will present the results of the richest outflow observed in an X-ray binary to date. When applying the same analysis to the outflow of the X-ray binary GRO J1655-40 we find a complex ionization structure of the wind, different in nature from that of AGNs. We use this structure to measure abundances of eighteen different elements in the wind, leading to inferences about the historical supernova explosion. The outflow is characterized by peaks in abundances of odd-Z elements, which have never before been observed in the X-ray, and originate in a massive type II supernova with supersolar metallicity. 

תאריך עדכון אחרון : 08/05/2024