David H Roberts

William R. Kenan, Jr. Professor Emeritus of Astrophysics

Departments/Programs

Physics

Degrees

Stanford University, Ph.D.
Amherst College, B.A.

Expertise

Galactic and extragalactic astrophysics. Radio astronomy. Theoretical astrophysics.

Profile

David Roberts is an experimental and theoretical astrophysicist who studies compact objects such as black holes in our Galaxy and the wider Universe. This is done using the techniques of high-resolution radio astronomy as well as optical and X-ray spectroscopy to examine the regions surrounding these objects. He is particularly interested in studying the magnetic fields in their environment. Webpage

Courses Taught

PHYS	15a	Advanced Introductory Physics I
PHYS	108b	Astrophysics
PHYS	168b	Introduction to Astrophysics

Awards and Honors

NASA Group Achievement Award for TDRSS Space VLBI (1988)

Scholarship

Roberts, D., Saripalli, L., & Subrahmanyan, R.. "X SHAPED RADIO GALAXIES AND THE NANOHERTZ GRAVITATIONAL WAVE BACKGROUND." Astronomy in Focus--Proceedings of the IAU Focus Meeting on Gravitational Waves, Honolulu, HI USA. 2016. (forthcoming)

Roberts,David H with Ojha, R., Wardle, J., Homan, D., Aller, M., Aller, H., & Hughes, P.,. "VLBI Polarimery: A Faraday Screen in 3C273?." Quasar Cores and Jets, Proc. 25th Meeting of the IAU (2007). (forthcoming)

Roberts, D., Cohen, J., Lu, J., Saripalli, L, & Subrahmanyan, R.. "THE ABUNDANCE OF X-SHAPED RADIO SOURCES: VLA SURVEY OF 52 SOURCES WITH OFF-AXIS DISTORTIONS." Astrophysical Journal (Supplements) 220. (2015): 7--38.

Roberts, D., Saripalli, L., & Subrahmanyan, R.. "THE ABUNDANCE OF X-SHAPED RADIO SOURCES: IMPLICATIONS FOR THE GRAVITATIONAL WAVE BACKGROUND." Astrophysics Journal (Letters) 810. (2015): L6--L19.

Roberts, David H., Wardle, John F. C., & Marchenko, Valerie V.*. "Structure and Linear Polarization of the Kiloparsec-Scale Jet of the Quasar 3C345." Astronomical Journal 145. (2013): 49-57.

Roberts, David H. & Wardle, John F. C.. "Evidence for Highly Relativistic Velocities on Kiloparsec Scales in the Quasar 3C345." Astrophysical Journal (Letters) 759. (2012): L35-L39.

Bell, Michael R., Roberts, David H., & Wardle, John F. C.. "Structure and Magnetic Fields in the Precessing Jet System SS 433 III. Intrinsic Brightness of the Jets from a Deep Multi-Epoch VLA Campaign." Astrophysical Journal 736. 2011 August 1 (2011): 118-131.

Roberts, D. H, Wardle, J. F C., Bell, M., Mallory,* M., Marchenko,* V., & Sanderbeck*, P.. "Structure and Magnetic Fields in the Precessing Jet System SS 433 II. Intrinsic Brightness of the Jets." Astrophysical Journal 719. 2 (2010): 1918--1925.

Roberts, David H., Wardle, John F. C., Lipnick, Scott L.,* Selesnick, Philip L.,* & Slutsky, Simon*. "Structure and Magnetic Fields in the Precessing Jet System SS 433. I. Multifrequency Imaging from 1998." Astrophysical Journal 676. March 20, 2008 (2008): 584-593.

Roberts, David H with Cheung C., Wardle, J., Moellenbrock, G., & Homan, D.. "Multi-Frequency VSOP and VLBA Polarization Observations on 3C279 and 3C345." Future Directions in High Resoultion Radio Astronomy (2005): 174-176.

Roberts,David H with Aller, H, Aller, M., Huges, P., Homan, D. & Wardle, J.. "Observations of Oblique Polarization Structures in Active Extragalactic Radio Jets." Future Directions in High Resolution Radio Astronomy. Jonathan D. Romney and Mark J. Reid (Astron. Soc. Pacific), 2005. 165-167.

Roberts,David H with Chen T., Wardle, J., Cheung, C., & Moellenbrock, G.. "HALCA and VLBA Observations of 3C454.3." Future Directions in High Resolution Radio Astronomy. Jonathan D. Romney and Mark J. Reid (Aston, Soc. Pacific), 2005. 77-81.

Roberts,David H with Ojha R. Wardle, J. Horman, D., Aller, M., Aller, H., & Hughes, P.. "VLBI Polarimetry: A Faraday Screen in 3C273?." Future Directions in High Resolution Radio Astronomy. Jonathan D. Romney and Mark J. Reid, ( Astron. Soc. Pacific), 2005. 195-197.

Roberts,David H with Wardle, J., Homan, D., & Cheung, C.. "The Ultra-Fast Quasar PKS 1510-089: Direct Evidence fo ra Changing Orientation of the Central Engine." Future Directions in High Resolution Radio Astronomy (2005): 67-71.

Roberts,David H with Ojha, R., Homan, D., Wardle, J., Aller, M., Aller, H., & Hughes, P. "Parsec-scale Blazar Monitoring: The Data." Astrophys. J. (Supp.) 150. (2004): 187-237.

Roberts, David H with Ohja, R., Homan, D., & Wardle, J.. "Proper Motions, Flux and Polarization Variability from Parsec Scale Blazar Monitoring." New Astron. Rev. 47. (2003): 637-640.