MARTIN GASKELL

Contact
Information:
Office:
RLM 17.202
Telephone: (512) 471-1348
E-mail: gaskell@astro.as.utexas.edu
Research
Interests
My main area of study
is the theory and observations of the violent processes going on around
supermassive black holes in quasars and active galactic nuclei (AGNs).
These black holes have masses of up to 10 billion times the mass of our
sun, and include the most powerful, compact, steady-state energy sources in the
universe. The
principle goals of my research are (a) to understand what AGNs are like
and just how they generate their tremendous energy, and (b) to
understand the cosmological evolution of supermassive black holes and their
co-relationships with their host galaxies. This research involves things
ranging from theoretical calculations on computers to getting
data from the
Hubble Space Telescope, a variety of X-ray satellites (such as
Chandra, RXTE, and Swift), and from all sorts of ground-based
telescopes. One of my long-term interests has been using the
variability of the radiation from AGNs to probe what is going on around the
supermassive black holes, and in doing this I work with many astronomers around
the world. Other things I have worked on in addition to supermassive
black holes include supernova explosions, stellar populations in normal
galaxies, and astronomical instrumentation.
Education
B.S. -
M.S. & Ph.D. -
Recent Papers
(from 2007 onwards only)
(present or former student
co-authors are followed by an asterisk)
Breedt, E.,
Arevalo, P., McHardy, I. M.,
Uttley, P., Sergeev, S. G.,
Minezaki, T., Yoshii,Y., Gaskell, C. M.,
Cackett, E., Horne, K., & Koshida, S., Mon. Not. Roy. Astron.
Soc. submitted.
A Simple Method for Making Non-Linear Fits to Data Sets with no Independent Error-Free Coordinate
Gaskell, C. M., Pub. Ast. Soc. Pacific
submitted
Line Shifts, Broad-Line Region Inflow, and the Feeding of AGNs
Gaskell, C. M. & Goosmann, R. W., Astrophys. J. submitted [arXiv:0805.4258]
Snedden, S. A.* & Gaskell, C. M., Astrophys. J. submitted.
Gaskell, C. M., Klimek, E. S.*, & Nazarova, L. S. 2007, Astrophys. J. submitted [arXiv:0711.1025].Gaskell, C. M. & Benker, A. J.*, Astrophys. J. submitted [arXiv:0711.1013].
Gaskell, C. M., Goosman, R. W., Merkulova, N. I., Shakhovskoy, N. M., & Shoji, M.* 2007, Astrophys. J. Letts. submitted [arXiv:0711.1019].
The Accuracy of Supermassive Black Hole Masses Determined by the Single-Epoch Spectrum (Dibai) MethodBochkarev, N. G. & Gaskell, C. M. Astron. Letts. 35, 000 [arXiv:0809.4742]
How Polarization and Scattering can Reveal Geometries, Dynamics, and Feeding of Active Galactic NucleiGoosmann, R. W., Gaskell, C. M., & Shoji, M.* Comptes Rendus, in press.
Mem. Soc. Ast. Italiana., 79, 000 [arXiv: 0807.2889]
Structure and Kinematics of the Broad-Line Region and Torus of Active Galactic Nuclei
Gaskell, C. M., Goosmann, R. W., & Klimek, E. S.* 2008,
Accretion Disks and the Nature and Origin of AGN Variability
Gaskell, C. M. 2008, Revista Mexicana de Astronomia y Astrofisica (Serie de Conferencias) 32, 1
Transformations between 2MASS, SDSS, and BVRI Photometric Systems: Bridging the Near Infrared and Optical
Bilir, S., Ak, S., Karaali, S., Cabrera-Lavers, A., Chonis, T. S.*, and Gaskell, C. M., 2008, Monthly Notices Royal Astron. Soc. 384, 1178
Setting UBVRI Photometric Zero-Points Using Sloan Digital Sky Survey ugriz Magnitudes
Chonis, T. S.* & Gaskell, C. M. 2008, Astron. J., 135, 264
The Case for Optically Thick High-Velocity Broad-Line Region Gas in Active Galactic Nuclei
Snedden, S. A.*, & Gaskell, C. M. 2007, Astrophys. J., 669, 126
The Origin of Wavelength-dependent Continuum Delays in AGNs - A New Model
Gaskell, C. M. 2007, in The Central Engine of Active Galactic Nuclei: ASP Conf. Ser., 373, 596.
Modeling the Polarization of Dusty Scattering Cones in Active Galactic Nuclei
Goosmann, R. W., Gaskell, C. M., & Shoji, M.* 2007 in The Central Engine of Active Galactic Nuclei ASP Conf. Ser., 373, 485.
Hubble Space Telescope Ultraviolet Spectroscopy of 14 Low-Redshift Quasars
Ganguly, R, et al., 2007, Astron. J. 133, 479
Modeling optical and UV polarization of AGNs. I. Imprints of individual scattering regions
Goosmann, R. W.* & Gaskell, C. M. 2007, Astron. Astrophys., 465, 129.
X-Ray/Ultraviolet Observing Campaign of the Markarian 279 Active Galactic Nucleus Outflow: a close look at the absorbing/emitting gas with Chandra-LETGS
Costantini, E, ..., Gaskell, C. M., ... Klimek, E. S.*, & Hedrick, C. H.* 2007, Astron. Astophys. 461, 121.
Chemical Abundances in an AGN Environment: X-Ray/UV Campaign on the Markarian 279 Outflow
Arav, N., ... Gaskell, C. M., et al. 2007, Astrophys. J., 658, 829.
AGN Polarization Modelling with STOKES
Goosmann, R. W.*, Gaskell, C. M. & Shoji, M.* 2007, IAU Symposium, 238, 375
Older Publications - see ADS
Miscellaneous
- Fellow of Royal Astronomical Society (RAS).
- Member of Space and High Energy Astrophysics Commission
(Commission 44) of the International
Astronomical
- Member American Astronomical Society (AAS).
- Member High Energy Astrophysics Division (HEAD).
- Five-time
finalist for Association of Students of the University of Nebraska annual
Outstanding Educator Award
- Nine-time
recipient of
- Mortar Board
Professor of the Month (twice)
- Kappa Delta
Educator of the Month
- Listed in Who's Who, Who's Who of American Men and Women of Science, and Who's Who of American Educators
My Musical Compositions
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