Tuesday, October 29, 2024
03:30 AM - 05:00 PM
ASD Colloquium (Hybrid)
Supernova remnants as particle accelerators: results from X-ray studies
Stephen Reynolds (North Carolina State University)
Fast particles, with energies far above thermal, are ubiquitous in astrophysics, playing important roles in star formation, galactic structure, active galaxies, and elsewhere. It is now generally accepted that fast electrons and ions are produced through the diffusive shock acceleration process, with the strong shock waves from supernova remnants (SNRs) a prime candidate for acceleration sites. In particular, electrons make themselves apparent through synchrotron radiation at photon energies from radio through hard X-rays, and through inverse-Compton scattering in gamma rays. Synchrotron radiation dominates the X-ray spectrum of a handful of Galactic SNRs, and contributes substantially to that of several more. These objects allow detailed study of the electron populations and the local environments of their acceleration. I shall summarize the properties of this population of X-ray synchrotron SNRs (XSSNRS), and describe in detail results on several objects. Ongoing monitoring of the youngest Galactic SNR G1.9+0.3 with the sub-arcsecond spatial resolution of the Chandra X-ray Observatory has allowed the characterization of velocities and brightness changes, both increases and decreases, on length scales of a small fraction of the remnant radius. These results and others pose significant problems for theoretical modeling of electron acceleration.
Read more about this event Stephen Reynolds (North Carolina State University)
Fast particles, with energies far above thermal, are ubiquitous in astrophysics, playing important roles in star formation, galactic structure, active galaxies, and elsewhere. It is now generally accepted that fast electrons and ions are produced through the diffusive shock acceleration process, with the strong shock waves from supernova remnants (SNRs) a prime candidate for acceleration sites. In particular, electrons make themselves apparent through synchrotron radiation at photon energies from radio through hard X-rays, and through inverse-Compton scattering in gamma rays. Synchrotron radiation dominates the X-ray spectrum of a handful of Galactic SNRs, and contributes substantially to that of several more. These objects allow detailed study of the electron populations and the local environments of their acceleration. I shall summarize the properties of this population of X-ray synchrotron SNRs (XSSNRS), and describe in detail results on several objects. Ongoing monitoring of the youngest Galactic SNR G1.9+0.3 with the sub-arcsecond spatial resolution of the Chandra X-ray Observatory has allowed the characterization of velocities and brightness changes, both increases and decreases, on length scales of a small fraction of the remnant radius. These results and others pose significant problems for theoretical modeling of electron acceleration.
Wednesday, October 30, 2024
03:00 PM - 04:30 PM
Scientific Colloquium
Cosmological Puzzles from JWST's Galaxies
Julian Muñoz - (University of Texas)
Read more about this event Julian Muñoz - (University of Texas)
Tuesday, November 05, 2024
03:30 AM - 05:00 PM
ASD Colloquium (Hybrid)
Wednesday, November 06, 2024
01:00 PM - 02:00 PM
Virtual Chat with the Code 600 Director
Everyone is Welcome!
ACTUAL TIME: 1:10 - 1:55
Read more about this event ACTUAL TIME: 1:10 - 1:55
Thursday, November 14, 2024
12:00 PM - 01:00 PM
SED Director’s Seminar
Please join us for the SED Director’s Seminar hosted by the Gravitational Astrophysics Laboratory, Code 663!
More information to come!
Read more about this event More information to come!
Tuesday, November 19, 2024
03:30 AM - 05:00 PM
ASD Colloquium (Hybrid)
Jacqueline McCleary (Northeastern)
Read more about this event Congratulations to the ASD Winners of 2024 Robert H. Goddard Awards 665/Jonathan Gardner, 662/Michale Loewenstein (Univ of...
Thursday, August 01, 2024Jane Rigby, an astronomer who grew up in Delaware, is the chief scientist of the world’s most powerful telescope. A prolific ...
Friday, May 03, 2024Contact Us
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