Scott
M. Ransom
Associate
Astronomer
NRAO
520 Edgemont Rd.
Charlottesville, VA USA
22901
Phone / Fax:
434-296-0320 / 0278
Email: sransom at
nrao dot edu
My GPG Key.
My CV.
I am a staff astronomer at NRAO-Charlottesville
specializing in pulsar
research.
In particular, I search for exotic pulsars (such as binary
and/or millisecond pulsars or MSPs) and then time
them, using their atomic clock-like rotational characteristics to probe
as much basic physics or astrophysics as possible.
Prior to August 2004, I was a postdoctoral researcher at McGill University in Montreal in Vicky Kaspi's pulsar group.
Before that, I was a graduate student in the Harvard Astronomy Dept.
If you are interested (or extremely bored), you can read my thesis here.
PRESTO is the
suite of pulsar search and analysis software (written in C and Python) that I wrote, maintain, and
use.
The
GBT Pulsar Spigot is the pulsar instrument that I am
responsible for (which was developed by NRAO/Caltech with much of the
work done by David
Kaplan).
Recent News:
Nov 2007:
- pySLALIB: Over the past
few days I put together a complete set of python+numpy wrappers (using the fantastic f2py) for the SLALIB
positional astronomy library (developed by P.T. Wallace). The
release includes a complete copy of the Fortran source for SLALIB
itself. Everything is released under the GPL. Hopefully
some of you find it useful.
Feb
2006:
- Terzan
5 now has 33 pulsars -
although I think this is getting near the limit of what we can do with
the current GBT.
The two most recent ones were found by my summer student Ben Sulman
using very deep stack
searches of all our data. We have timing
solutions for 31
of the pulsars, including (we think), Ter5Q,
a highly eccentric (e = 0.72) binary MSP. Here
is a neat plot that shows an I-band NTT image (from S. Ortolani), with
VLA L-band contours (from Fruchter and Goss 2000), and the 31
timing-based pulsar positions.
- We finally convinced ourselves that the Backer-beater was real
and so we published a paper
on Ter5ad
(also available here).
You can see Jason
Hessels' poster
and our press
release from the recent AAS meeting as well. Just how fast is
716 Hz? That is what
the pulsar would sound like if we amplified its signal from the GBT by
about 5000 times!
- Recent work on the 7 new M28
pulsars has shows us that M28C
is highly eccentric (e = 0.84) and very interesting...
Oct
2005:
- Terzan
5 now has 31 pulsars, and we have timing
solutions for 28
of them!
- One of them, Ter5ad,
appears to (finally) be a "Backer-beating" 1.39ms pulsar! We're
still trying to rule out that it isn't a harmonic of a 2.78ms, pulsar,
though.
- Another one, Ter5ae, is a new
"Black-Widow" type pulsar in a compact binary that my summer student
Mike McCarty found using an automated version of Adam Chandler's
"Dynamic Power Spectrum" technique.
- The GBT has found at least
55
new globular cluster
pulsars since it has been in operation! Most of these have
been with the fantastic SPIGOT+S-band receiver system.
Feb
2005: Two more MSPs (Z
and aa)
in Terzan 5 make 26 total!
Jan
2005: We've used the GBT to find 21
new binary and millisecond pulsars in globular cluster Terzan
5.
Here is the abstract
and full
text of the Science paper.
Aug 2004: Moved to
Charlottesville from Montreal.
Last Modified 2 Feb 2006