Welcome to Jonathan Gelbord's website
main research page
(a complete, hyperlinked list of
publications and presentations, plus a collection of
astronomical tools and references I've developed)
(I use this as my homepage, loaded with links I find useful)
I'm currently a research scientist
with Eureka Scientific, Inc.,
where I conduct NASA-suppored astronomical investigations using both
archival and new observational data.
Previously, I was a member of the research faculty at the
Penn State University
Department of Astronomy &
where I had joined the Swift
satellite operations team in 2009. Before that, I had
postdoctoral research positions with
Astronomy and Cosmology group in the
Department of Physics and
the Kavli Institute for Astrophysics
and Space Research at MIT.
I earned my doctorate from the Johns
Hopkins Department of Physics
and Astronomy and my undergraduate degree from
My research is primarily focused on multiwavelength
observational studies of active galactic nuclei (AGN), although my
interests also include X-ray emission from star-forming galaxies,
astronomical surveys, AGN variability and more generally transient
phenomena. The subjects of my research programs include:
Some of the research tools I have developed may be found on
my research page,
along with a complete listing of my publications.
- The structures around active galactic nuclei:
AGN are pinpoints of light found at the
centers of some galaxies that in some cases can outshine the
billions of stars that surround them.
They are powered by accretion onto supermassive black holes
Around the SMBHs are a series of structures where the processes
of AGN take place.
These include an accretion disk, a whirlpool through which the
infalling material spirals, releasing the energy that we
dusty clouds that lie beyond the accretion disk, acting as a
fuel reservoir and potentially obscuring the AGN from some lines
and outflowing winds, driven from the central regions, through
which the AGN can influence the surrounding galaxy.
I use broad-band photometry, X-ray and optical spectroscopy and
variability to constrain models of these structures.
- Quasar jets: Some AGN eject streams of particles at
velocities that approach the speed of light. These relativistic
outflows can extend to Mpc scales, influencing their host
galaxies and beyond. I am part of an international team that
combines X-ray data, optical images and spectra from the Hubble
space telescope and ground-based observatories, infrared data
from the Spitzer space telescope and radio maps from VLA and
ATCA to better understand the processes, composition and power
of these systems.
- Transient phenomena: Things that go bump in the night,
including tidal disruption events (in which a star is ripped
apart as it passes too close to a SMBH), Gamma Ray Bursts, and
- Astronomical surveys: Large area surveys are the key both
to finding rare objects (the proverbial needles in the
haystack that might also be rosetta stones) and to conducting
minimally-biased censuses. I use data mining techniques to comb
through catalogs with millions of records, pulling together data
from different catalogs as well as new observations to find new
and unusual objects. My discoveries have included galaxies
showing the after-effects of recent tidal disruption events,
obscured AGN, and a star in our galaxy caught in the act of
flaring in both X-ray and ultraviolet light.
When I'm not working there's a good chance I'll be on a road trip
or helping my wife with her business,
(eco-friendly wedding dresses and sustainable bridalwear,
using organic, environmentally-friendly and reclaimed materials).
Otherwise, I'm still discovering the joys of home ownership, which
seems to be a hobby in itself...
The best way to reach me is via e-mail at
jonathan [AT] eurekasci [DOT] com
(please forgive the written-out address; I'm trying to elude the
spam-bot e-mail sniffers...).
My link collection is
the web page I've put the most effort into, as it's the one I use
for my startup page.
It looks best when viewed with a browser that supports tables and
frames (e.g., Netscape 2.2¹ or later). Of course, if you're still
using a browser that doesn't support frames, then you've got bigger
problems than whether you can load my pages...
¹The fact that Netscape 2.2 was a cutting-edge browser when I
first wrote the above statement is a clue to how long ago that was...
Eureka Scientific, Inc.
jonathan [AT] eurekasci [DOT] com