PhD Proposal: Peter Breiding
Location
Physics : 401
Date & Time
May 18, 2016, 2:00 pm – 4:00 pm
Description
ADVISOR: Dr. Eileen Meyer
TITLE: Testing the IC/CMB Model of Extended X-ray Emission for Large Scale Quasar Jets with the Fermi/LAT
ABSTRACT: It has been observed with the Chandra X-ray Observatory since the early 2000s that many powerful quasar jets show X-ray emission on the kpc-scale. In many cases these X-rays cannot be explained by the extension of the radio-optical spectrum produced by synchrotron emitting electrons in the jet, since the observed X-ray flux is too high. These jets are believed to be outflows of relativistic plasma from the centers of a class of galaxies known as active galaxies, where the central black hole is actively accreting matter (Ho. & Kormendy, 2000). A widely accepted model for the X-ray emission posits that the X-rays are produced when relativistic electrons in the jet up-scatter ambient cosmic microwave background (CMB) photons via inverse Compton scattering from microwave to X-ray energies (the IC/CMB model). However, based on prior work by Georganopoulos et al. 2006, Meyer & Georganopoulos 2014, and Meyer et al. 2015, explaining the X-ray emission for these jets with the IC/CMB model requires high levels of IC/CMB gamma -ray emission. The goal of my research is to test the viability of IC/CMB as the X-ray emission process by looking for the IC/CMB gamma-ray emission using the Fermi/LAT, setting upper limits when it is not detected. If we detect, or set upper limits to, the IC/CMB gamma-ray flux at levels below those required to explain the X-ray emission, we can reject IC/CMB as the X-ray emission process.
TITLE: Testing the IC/CMB Model of Extended X-ray Emission for Large Scale Quasar Jets with the Fermi/LAT
ABSTRACT: It has been observed with the Chandra X-ray Observatory since the early 2000s that many powerful quasar jets show X-ray emission on the kpc-scale. In many cases these X-rays cannot be explained by the extension of the radio-optical spectrum produced by synchrotron emitting electrons in the jet, since the observed X-ray flux is too high. These jets are believed to be outflows of relativistic plasma from the centers of a class of galaxies known as active galaxies, where the central black hole is actively accreting matter (Ho. & Kormendy, 2000). A widely accepted model for the X-ray emission posits that the X-rays are produced when relativistic electrons in the jet up-scatter ambient cosmic microwave background (CMB) photons via inverse Compton scattering from microwave to X-ray energies (the IC/CMB model). However, based on prior work by Georganopoulos et al. 2006, Meyer & Georganopoulos 2014, and Meyer et al. 2015, explaining the X-ray emission for these jets with the IC/CMB model requires high levels of IC/CMB gamma -ray emission. The goal of my research is to test the viability of IC/CMB as the X-ray emission process by looking for the IC/CMB gamma-ray emission using the Fermi/LAT, setting upper limits when it is not detected. If we detect, or set upper limits to, the IC/CMB gamma-ray flux at levels below those required to explain the X-ray emission, we can reject IC/CMB as the X-ray emission process.
