Program Overview

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Physics 612: High Energy Astrophysics

Course Description

The Universe is filled with diverse objects and phenomena ranging from those with very low characteristic temperatures, such as the 2.7 K Cosmic Microwave Background Radiation, to the ultrahigh energy cosmic rays in which a single particle can carry 10 J or more of energy. Accordingly, in order to attempt a complete understanding of cosmic objects and events, astrophysicists have been driven to conduct studies over the entire electromagnetic spectrum. In this course, the focus will be on the study of high energy astrophysics, that is to say, the field of astronomy that concerns itself with objects and phenomena having a characteristic temperature greater than about 10^6 K or equivalently 0.1 keV. This includes the X-ray and gamma-ray bands of the electromagnetic spectrum, cosmic rays, and neutrinos from the Sun and supernovae.

Course Objectives

This course is intended to provide the student with sufficient background material and knowledge in order to appreciate current research literature in high energy astrophysics. It will draw on graduate level physics and astronomy as prerequisites.

Textbooks

• "High Energy Astrophysics" (2nd edition) by Malcolm Longair (Cambridge University Press) Vols 1 and 2
• "Exploring the X-ray Universe" by Charles and Seward (Cambridge)
• "Radiative Processes in Astrophysics" by Rybicki and Lightman (Wiley)

Assessment

The grading criteria for this course are divided between:

• Problem sets (40%)
• A written observing proposal (40%)
• Attendance and class participation (20%)

Proposal Guidelines

Each submitted proposal must conform precisely to the requirements of the most recent Announcement of Opportunity for the mission or observatory that the class, as a whole, has selected. The class will choose between Chandra and XMM-Newton as the possible missions. An oral presentation to the class where you describe and defend your proposal will also be required. Criteria for grading of proposals will be based on:

• The description of the overall scientific goal of the proposal
• The extent to which the proposed observations are effective at meeting the proposed science goals
• The technical feasibility of the observations
• The accuracy of supporting simulations
• Your defense of the proposal

Course Schedule

• Jan 20 - Introduction - L1 Chap 1
• Jan 23 - Ionization losses - L1 Chap 2 & Section 7.2
• Jan 27 - Photoelectric effect - L1 Sections 4.1 & 4.2
• Jan 30 - Compton scattering and Electron-positron pair production - L1 Sections 4.3.1, 4.3.2, 4.4, & 4.7
• Feb 3 - Detectors - L1 Sections 6.4 & 6.5 (Gas proportional Counters)
• Feb 6 - Detectors (continued) (X-ray CCDs)
• Feb 10 - Detectors (continued) (Quantum Calorimeters)
• Feb 13 - Reflectivity, optical constants
• Feb 17 - X-ray telescopes, gratings
• Feb 20,24 - Thermal bremsstrahlung (L1, chap 3; R&L chap 5)
• Feb 27 - Radiative recombination, Milne relations (R&L p.284ff)
• Mar 2 - Ionization rates, Dielectronic recombination, collisional ionization equilibrium
• Mar 5 - Nonequilibrium ionization, H- and He-like emission lines
• Mar 9 - Line emission processes, Cyclotron radiation (L2, 18.1.2)
• Mar 12 - Synchrotron radiation (heuristic derivation) (L2 Chap 18)
• Mar 23 - Synchrotron radiation (detailed derivation) (L2 Chap 18)
• Mar 26 - Polarization of synchrotron radiation (L2, 18.1.6), Intro to Crab Nebula
• Mar 30 - Energy loss from pulsars (Ostriker & Gunn 1969), Min energy condition in pulsar wind nebula (L2, 19.5)
• Apr 2 - Lifetime of synchrotron radiating electrons (Pacholczyk "Radio Astrophysics", p.147ff)
• Apr 6 - Synchrotron self-absorption (L2 p.256ff), Inverse Compton (L1, 4.3.3)

Useful References

• HIFLUGCS (The HIghest X-ray FLUx Galaxy Cluster Sample)
• "A Flux-limited Sample of Bright Clusters of Galaxies from the Southern Part of the ROSAT All-Sky Survey: The Catalog and log N-log S" De Granid et al., ApJ, 514, 148 [1999]
• "X-ray Emission from Clusters of Galaxies" Sarazin, Rev. Mod. Phys., 58, 1 [1986]
• "Confinement of the Crab pulsar's wind by its supernova remnant" Kennel & Coroniti, ApJ, 283, 694 [1984]
• "On the Nature of Pulsars. I. Theory" Ostriker & Gunn, ApJ, 157, 1395 [1969]
• "Supernovae. Part II: the aftermath" Trimble, Rev. Mod. Phys., 55, 511 [1983]
• "Supernovae. Part I: the events" Trimble, Rev. Mod. Phys., 54, 1183 [1982]
• "Bremsstrahlung, Synchrotron Radiation, and Compton Scattering of High-Energy Electrons Traversing Dilute Gases" Blumenthal & Gould, RMP, vol 42, p 237 [1970]
• "Cosmic Magnetobremsstrahlung (Synchrotron Radiation)" Ginzburg & Syrovatskii, ARA&A, 3, 297 [1965]
• "Overview of Collisional Plasma Modeling" Smith & Brickhouse, published on CXC Web site [June 2002]
• "Effect of Iron Ionization Balance on X-ray Spectral Analysis" Masai, Astron. Astrophys., 324, 410 [1997]
• "Quantum Calorimetry" Stahle & McCammon, Physics Today, vol 52, issue 8, p 32 [August 1999]
• "Advanced CCD Imaging Spectrometer (ACIS) Instrument on the Chandra X-Ray Observatory" Garmire et al, SPIE [2002]
• Rise time rejection in the ASCA GIS instrument, ABC Guide to ASCA Data Analysis
• "X-ray astronomy missions" Bradt, Ohashi, & Pounds, ARA&A, volume 30, page 391 [1992]
• "Principles of operation of multiwire proportional and drift chambers" Sauli, CERN Yellow Report 77-09 [1977]
• "The Einstein (HEAO 2) X-ray Observatory" Giacconi, et al., ApJ, volume 230, page 540 [June 1979]
• "Instrumental technique in X-ray astronomy" Peterson, ARA&A, Volume 13, page 423 [1975]
• "The collisionless nature of high-temperature plasmas" O'Neil & Coroniti, RMP, vol 71, p S404 [March 1999]
• "Cosmic rays: the most energetic particles in the universe" Cronin, RMP, vol 71, p S165 [March 1999]
• "X-Rays from the rest of the Universe" Helfand, Physics Today, vol 48, issue 11, page 58 [November 1995]
• "Wilhelm Conrad Rontgen and the glimmer of light" Seliger, Physics Today, vol 48, issue 11, page 25 [November 1995]
• Special issue: "X-Rays 100 Years Later" Physics Today, vol 48, issue 11 [November 1995]

Recent Results in High Energy Astrophysics

• XMM-Newton: Dust echos around GRB
• Chandra: Element enrichment in The Antennae galaxy
• Integral: Anti-matter in the Galactic center
• Advanced Composition Explorer (ACE): Current
  • Archive Upper Limit on 3He Fluence in Solar Energetic Particle Events
  • Archive Galactic Cosmic Ray Neon and Iron-Group Isotopic Abundances Agree with Wolf-Rayet Star Model
  • Archive Direct Evidence for Variation in the Energy Loss of Galactic Cosmic Rays due to Changing Levels of Solar Modulation
• Astronomy Picture of the Day
• NASA Space Science Missions

Possible Topics to be Covered

• Overview/Historical introduction
• Ionization losses of high energy particles interacting with matter
• Photon interactions with matter: Photoelectric effect, Compton scattering
• Photon interactions: pair production
• High energy particle and photon detectors
• Telescopes and Observatories
• Bremsstrahlung
• Radiative recombination (Milne relation)
• Line radiation, ion & recomb rates, ionization balance
• Cyclotron radiation
• Synchroton radiation
• Blackbody radiation
• Inverse Compton scattering/Kompaneets eqn.
• SNe (Supernovae): Rates/Types/progenitors/Explosion mechanisms
• SNRs (Supernova Remnants): thermal emission, shock waves, Sedov solution, other evolutionary models, Coloumb equil., nonequilibrium ionization, cosmic ray shock acceleration
• Binary X-ray sources: evidence for the black hole event horizon?
• COGs (Clusters of Galaxies): Optical/X-ray classifications, luminosity functs, correlations, origin of Fe, Physical processes: sound speed, mean free paths, T equilibration timescales, heat conduction, convective stability, radiative cooling, X-ray structure, temp, binding masses, SZ effect, clusters as cosmological probes
• AGN: Unified Scenario/Broad Fe lines

Professor and Meeting Information

• Professor: Jack Hughes
• Meeting Times: Tues 2:50PM-4:10PM (ARC 206) Fri 1:10PM-2:30PM (ARC 108)