Panchromatic Robotic Optical Monitoring and Polarimetry Telescopes
Temporary Telescopes 5, 3 and 2 (March 2005).
The University of North Carolina at Chapel Hill is currently building PROMPT,
which stands for Panchromatic Robotic Optical Monitoring and Polarimetry
Telescopes, on Cerro Tololo, on the ridge between the GONG and 1.3-m
telescopes. PROMPT's primary objective is rapid and simultaneous
multiwavelength observations of GRB afterglows, some when they are only tens
of seconds old. In addition to measuring redshifts by dropout, and early-time
SFDs and extinction curves of sufficiently bright afterglows in unprecedented
detail, PROMPT will facilitate quick response observations at 8.1-m Gemini
South and 4.1-m SOAR. PROMPT will also serve as a platform for undergraduate
and high school education throughout the state of North Carolina.
When completed in early 2006, PROMPT will consist of six 0.41-m
Ritchey-Chrétien telescopes by RC Optical Systems on rapidly slewing (9°/sec)
Paramount ME mounts by Software Bisque, each under a clamshell dome by Astro
Haven. Five of these telescopes are being outfitted with rapid-readout (<1
sec) Alta U47+ cameras by Apogee, which make use of E2V CCDs. The sixth is
being outfitted with an LN2-cooled Micro-Cam by Rockwell Scientific for NIR
imaging. Each mirror and camera coating combination has been optimized for a
different wavelength range, including a u-band optimized telescope. Although
other filters will be available, PROMPT will automatically observe GRB
localizations in ugrRizYJH, six of them simultaneously. The R-band telescope
will additionally measure polarizations. The polarimeter is being designed
and built at UNC-Chapel Hill's Goodman Laboratory for Astronomical
PROMPT is being built in two phases: Phase I, which was funded by $130,000
from UNC-Chapel Hill and a $100,000 gift from alumnus Leonard Goodman, began
in September 2004 and is now complete. Phase I consisted of enclosure
construction and the assembly of temporary 0.36-m Schmidt-Cassegrain
telescopes by Celestron, with the goal of establishing reliable and robust
operations, and to test software. Phase II, which is funded by $912,000 from
NSF's MRI and PREST programs, begins in December 2005 and will consist of
upgrading to final optics, the NIR camera, and the polarimeter.
Although early science technically does not begin until after the December
trip, PROMPT has already observed nine GRB localizations, two within minutes
of the burst, and two with detected afterglows. These results are being
prepared for submission to the ApJ in combination with Follow-Up Network for
Gamma-Ray Bursts (FUN GRB) Collaboration data from the 4.1-m SOAR, 3.5-m ARC,
1.5-m Kuiper, and 0.9-m SARA telescopes. PROMPT Collaboration institutions
(see below) will gain access to 30% of PROMPT's time beginning January 1st,
2006, and the broader US astronomical community will be invited to apply for
10% of PROMPT's time with awards beginning in Semester 2006B.
PROMPT is under the control of "Skynet", a prioritized queue scheduling
that we are developing at UNC-Chapel Hill. Skynet is written in LabView and
runs on a computer at UNC-Chapel Hill's Morehead Observatory. Skynet
interacts with MySQL databases and commands dumb-by-design "Terminator"
programs at each telescope. Images are automatically transferred back to a
1.1 terabyte RAID 5 with tape backup at Morehead Observatory, making use of
communication libraries that we wrote for remote use of SOAR. Users can
submit jobs and retrieve data from any location via a PHP-enabled web server
that interacts with the MySQL databases. However, GRBs receive top priority
and are automatically added to the queue via a socket connection.
Furthermore, we have written Terminator very generally, such that any mount
that can be controlled by "The Sky" and any camera that can be controlled by
MaxIm DL, or mounts and cameras that are ASCOM compliant, can easily be
integrated into Skynet. On this note, work is underway to integrate a few
half-meter class facilities across the US this academic year, supported in
part by an NSF CAREER grant. Skynet will then synchronize GRB observations
across these telescopes, which makes interpreting SFDs much easier, especially
if the afterglow is not fading as a power law at early times. When not
chasing GRBs, which is most of the time, network members will be able to queue
jobs on each other's telescopes, including PROMPT, at a guest priority level,
giving them access to additional facilities and instrumentation, not to
mention sky coverage and weather flexibility.
Between HETE-2, Integral, and now Swift, we expect PROMPT to observe GRB
localizations on the rapid timescale about once every three months, and on
longer timescales about once every week. Given our best guestimates about the
star-formation rate at high redshifts, we might observe z > 5 GRBs on the
rapid timescale as often as once per year, and z > 7 GRBs on the rapid
timescale perhaps once every two to three years. PROMPT's ability to observe
afterglows simultaneously in many filters, including NIR filters, and to do so
quickly before the afterglow fades away will allow it to "promptly" pick out
Record breaker or not, we will use PROMPT to facilitate our quick response
programs on Gemini South and SOAR, which are only one mountaintop away.
UNC-Chapel Hill and the FUN GRB Collaboration, in coalition with the US/UK
Gemini GRB Collaboration, have been awarded 21 hours of quick response time on
Gemini South in Semester 2005B. Additionally, UNC-Chapel Hill has a
three-year commitment from the SOAR Board to interrupt on the rapid timescale.
Both telescopes are capable of NIR and optical spectroscopy and imaging, as
well as able to switch instruments within minutes. A trained GRB observer
will help coordinate PROMPT, SOAR, Gemini South, and FUN GRB Collaboration
efforts from UNC-Chapel Hill's new Henry Cox Remote Observing Center each
When not chasing GRBs, PROMPT will be used by undergraduate and high school
students across the state of North Carolina for a wide variety of projects.
In addition to UNC-Chapel Hill, PROMPT Collaboration institutions include
Appalachian State University, Elon University, Fayetteville State University,
Guilford Technical Community College, North Carolina Agricultural and
Technical State University, UNC-Asheville, UNC-Charlotte, UNC-Greensboro,
UNC-Pembroke, Western Carolina University, and Hampden-Sydney College just
across the border in southern Virginia. Each of these institutions will have
about 420 hours per year of observing time between the six PROMPT telescopes,
giving them guaranteed access to a professional observatory and the southern
Furthermore, since PROMPT is fully robotic, none of these institutions will
have to raise additional money to send students to Chile to use the telescopes
-- a very expensive proposition. Instead, students will simply submit
observing requests to Skynet using the web interface. PROMPT will
automatically observe each target, usually within a few days, and then Skynet
will return the collected images to the students for analysis.
Finally, UNC-Chapel Hill's Morehead Planetarium and Science Center (MPSC) will
have about 2,300 hours per year for K-12 education and public outreach. MPSC
hopes to bring PROMPT into every high school in the state of North Carolina.
Funded by a $50,000 NASA/STScI IDEAS grant, MPSC is developing a curriculum
for high school science classes that will allow them to submit observing
requests to Skynet using the same web interface that the undergraduate
students will use. This curriculum will also satisfy new statewide graduation
PROMPT is funded by the National Science Foundation, the University of North Carolina at Chapel Hill, Leonard Goodman, the National Aeronautics and Space Administration, Dudley Observatory, Henry Cox, and the Pisgah Astronomical Research Institute.
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