Pisgah Astronomical Research Institute Radio and Optical Telescopes

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Pisgah Astronomical Research InstituteRadio and
Optical Telescopes

• J. D. Cline, M. W. Castelaz (PARI)
• D. Moffett
• (Furman University)
• M. Lopez-Morales
• (UNC-Chapel Hill)
• 15.01 AAS 197th Meeting, January 2001

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• The Pisgah Astronomical Research Institute (PARI)
  is a not-for-profit public foundation dedicated
  to providing research and educational access to
  radio and optical astronomy for a broad
  cross-section of users.
• PARI is located among the 160,000 Pisgah Forest
  acres controlled by the US Forest Service west
  of Asheville, North Carolina.
• The PARI 200 acre site is located in an area
  relatively free of light and radio interference.
  There are over 20 buildings providing more than
  100,000 square feet of temperature controlled
  operational space.

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• PARI is a research lab open to astronomers for
• on-site radio observations
• project development
• instrument development
• postdoctoral research
• Visiting astronomers are expected to support
  their research conducted at PARI through
  university, public or private grants.
• Visiting Astronomers are also encouraged to
  develop Educational Initiatives
• K-12 teacher workshops
• Promote requests to develop summer outreach
  programs to pre-college and pre-high school
  teachers
• Undergraduate research
• Graduate research
• Furthermore, PARI will provide
• the staff needed to assist in the visiting
  astronomers initiatives
• opportunities for the public to participate in
  general astronomy education
• remote access to 4.6-m radio telescope for schools

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• Two 26-m Radio Telescopes

• The 26-meter radio telescopes are multi-band
  antennae originally designed for tracking
  fast-moving, low Earth orbit satellites and
  manned spacecraft.
• The 26-meter radio telescopes have been upgraded
  with 20-bit encoders, one of which has computer
  controlled motors for precision tracking of
  celestial targets at sidereal rates.

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• The 12.2-m Telescope

• The 12.2 Meter radio telescope is a precision
  surface antenna protected by a Gore-Tex radome.
  The antenna is an elevation over azimuth
  configuration, controlled remotely via fiber
  optics from the main control center in building
  1. RF is also linked via fiber optics to the
  main control.
• Prime focus feeds currently in place support
• 6 cm (4.6 - 5.1 GHz) and 3 cm (10.6 - 10.7 GHz)
  reception. A removable cassegrain subreflector
  and feed assembly is also available for 6, 5, and
  4.5 cm (4.6-5.1, 6.0, and 6.7 GHz) operation.

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• The 4.6-m Telescope

The antenna is currently configured for 21 cm
(1.42 GHz) reception. Plans are to complete a
program for remote control of the radio telescope
via the Internet. The goal is to provide hands
on data collection using remote access of the
antenna for high school and college classes.
Additional feeds for 6, 5, 4.5, and 2 cm
(4.6-5.1, 6.0, 6.7, and 12.0-15.6 GHz) are
planned for this antenna.
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• The Jupiter-Solar Antenna

• Jupiter emits periodic energy bursts as its moon
  Io cuts through the magnetic fields of the
  planet. The energy output is equivalent to a
  thermal source with a temperature of 1,000,000
  K.
• To study the powerful radio emission variations
  as a function of frequency, R. Flagg, (Univ. of
  Florida), and Jim Sky (Radio Sky Publishing) have
  designed hardware to work with a pair of
  M-Squared 17-30LP7 log periodic yagis to be used
  between 17 and 30 MHz.
• Solar energy bursts are being measured during the
  day using this antenna facility.

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• Radio Observations

26-m antenna observations conducted thus far have
been used to test our receivers and detectors.
Below are some continuum and spectral-line
observations
Single spectrometer scan centered at 1420 MHz
showing spectral features from neutral hydrogen
gas (HI) as observed toward the active galaxy
Cygnus A.
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Bandpass-corrected HI spectrometer scans.
Integrated HI spectrum toward Cygnus A. Channels
have been assigned Doppler-shifted velocities
with respect to the observers rest frame. HI
emission, and absorption of radio emission from
Cygnus A by a distant galactic hydrogen can be
seen above.
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5-GHz false color image of the Orion Nebula
formed from slew scans. Blue is lowest
brightness, red is highest.
Three-dimensional representation of the above
5-GHz image.
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The Pisgah Survey for Detached Low-Mass
Eclipsing Binaries.
Observatory housing the 0.2-m telescope at PARI

• Scientific Motivation
• Recent advances in stellar modeling of low-mass
  stars and brown dwarfs have not been accompanied
  by an attempt to obtain accurate measurements of
  these objects' most fundamental parameters their
  masses and radii.

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• The observed mass-radius relation (see figure
  below) for stars below 1 M? has only six
  reliable measurements from the components of the
  eclipsing binaries CMDra, GJ2069A and YYGem.
  These few points are not enough to test and
  constraint the models.
• The solution to this problem, and the goal of
  this survey, is to find more low-mass detached
  eclipsing binaries, which can be used to directly
  measure masses and radii.
• The candidate systems will have a variation on
  brightness of at least 0.2 mag, V-I ? 2.0, and
  orbital period P? 2 days.

Logarithmic representation of the mass-radius
relation for stars below 1 M?. The lines
represent theoretical models from Baraffe
Chabrier, Tout et al.,DAntona Mazzitelli,
Dorman et al., and Neece (see references). The
points correspond to the components of CMDra,
GJ2069A, and YYGem.
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Parameters of the Survey

• The camera-telescope system yields a scale of
  2.25 per pixel, and a total field of 1.64 sq.
  deg. per image (see image below).
• Images are taken in the I band, reaching 15
  magnitude with S/N-ratio5 in three-minute
  exposures.
• The camera is operated at 25C, giving a dark
  count rate of less than 0.16 electrons per
  second.
• Under good weather conditions, the survey covers
  40 fields per night, centered in the equatorial
  plane. Ten of the fields are sampled at least 4
  times per night.

Sample field centered at RA16h30m19s,
Dec-024130. The image contains the 23.4x19.5
central arc-minutes of one of our 1.64 sq. deg.
test frames. The two stars marked appear as
suspected variables in the NSV Catalog. Their
apparent V magnitudes are 12.1 and 14.2,
respectively.
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Expectations and Goals
Based on theoretical calculations, we expect to
find one low mass detached eclipsing binary of
magnitude I lt 15, with orbital period ? 2 days in
every 35-40 fields surveyed. The survey will need
two months to sample this many fields, therefore
we expect to detect at least 15 binaries over
the three-year lifetime of the survey. As a
by-product, we will be able to detect all the
variables in the fields covered, down to our
magnitude limit. This will be a contribution to
variable stars databases initiated by other
ongoing projects like ASAS, OGLE or ROTSE. Adding
the necessary radial velocity follow-up of the
candidates discovered by our survey, the
determination of their masses and radii will
suppose a factor of 5 increase in the actual
knowledge of the mass-radius relation of the
lower main sequence.
References
Baraffe, I, Chabrier, G., 1996, ApJ, 461, L51.

DAntona, F. Mazzitelli, I. 1982, ApJ, 260,
722.
Delfosse, X., Forveille, T., Mayor,
M., Burnet, M. Perrier, C. 1999,AA,341,L63.
Dorman, B., Nelson, L.A., Chau, W.Y. 1989,
ApJ, 342, 1003. Leung, K.C.
Schneider, D. 1978, AJ, 83, 618.
Metcalfe, T.S.,
Mathieu, R.D., Latham, D.W. Torres, G. 1996,
ApJ, 456, 356. Neece, G.D. 1984, ApJ, 277, 738.

Tout, C.A., Pols,
O.R., Eggleton, P.P. Han, Z. 1996,MNRAS, 281,
257.
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K12 OUTREACH PROGRAM

• PARI has been awarded a grant from the Community
  Foundation of Western North Carolina to establish
  an Outreach Program.
• This program supports PARIs technical staff
  efforts to promote education in astronomy and
  related sciences in the public schools of North
  Carolina.
• The portable planetarium provides access and a
  tool for learning that has not previously been
  available to the schools of western North
  Carolina.
• We anticipate that this program will be made
  available to more than 5,000 students per year.

STARLAB? PORTABLE PLANETARIUM
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SGRA The School of Galactic Radio Astronomy

• Proposed as an experience-based school room for
  regional use by elementary, middle, and high
  school teachers and their students
• Reinforces student use of math, physics,
  chemistry,and computer science.
• Relies on Internet access to PARIs
  remote-controlled radio telescope.

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• The purpose of SGRA is to teach the basics of
  scientific inquiry, which includes methodology,
  critical thinking, and communication of results
  to grades 8-12.
• Curriculum includes electromagnetic radiation,
  chemistry, math skills such as graphing
  interpretation of graphs, contour maps, and
  trigonometry, computer skills, and technology.
• Process and evaluations of the SGRA will be
  instituted via online student observation
  logbooks and
  teacher feedback.

SGRA
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Workshop to be Hosted by PARI, August 2001 Small
Radio Telescopes in Modern Astronomy
PARI WILL PRESENT THE OPPORTUNITY FOR
ASTRONOMERS TO COME TOGETHER FOR THREE DAYS TO
SHARE AND COLLECT IDEAS IN RESEARCH AND
EDUCATION, INSTRUMENTATION, AND INNOVATIVE
PROGRAMS FOR RADIO TELESCOPES 3 TO 26 M
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Workshop Topics Include The role of radio
telescopes in surveys, long-term monitoring
projects, and networks. Using radio telescopes
for astronomy and astrophysics education.
Remote, robotic, and on-site observing modes,
instrumentation development, data collection and
web access.
FOR MORE INFORMATION, PLEASE LEAVE YOUR NAME ON
THE SHEET BELOW THIS POSTER.
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CONTACT INFORMATION

• Pisgah Astronomical Research Institute
• 1 PARI Drive
• Rosman, NC 28772-9614
• WWW.PARI.EDU
• Phone [phone]
• FAX [phone]
• For further information call or e-mail
• Don Cline dcline_at_pari.edu
• for future project questions
• James Powers jpowers_at_pari.edu
• for general and grant questions
• Michael Castelaz mcastelaz_at_pari.edu
• for education/astronomy-related questions
• Charles Osborne cosborne_at_pari.edu
• for hardware technical questions
• David Moffett david.moffett_at_furman.edu