Indias Perspective on Exoplanet Research

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Indias Perspective on Exoplanet Research
Suvrath Mahadevan
on behalf of Abhijit Chakraborty, Physical
Research Laboratory (PRL), Department of Space,
India
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Indias Perspective

• India is a relative newcomer to modern exoplanet
  research
• On going strategy
• Near Term (within next 1yr)
• Highly stable fiber fed spectrograph, PARAS,
  being commissioned at the Mt Abu 1.2m telescope
  in Jan 2010
• Long Term (next 5-10 years) possibilities
• Dedicated 2-2.5 m robotic telescope with PARAS
  for precision RV followup
• Possibilities of Space Missions in very
  preliminary discussion stage

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http//www.isro.org/chandrayaan/htmls/mission_sequ
ence.html
Polar Satellites Launch Vehicle (PSLV). Payload
consists of instuments built by ISRO, ESA, NASA,
and some other organizations.
ChandraYaan-1 Spacecraft, Indias Moon Mission
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PARAS PRL Advanced Radial Velocity All Sky Search

• Fiber-Fed Spectrograph
• Built to be very stable
• Fiber fed
• Temperature stabilized, and in a vacuum
  enclosure
• Star and Th-Ar on different fibers, so
  simultaneous calibration of Instrument Drift

Th-Ar
Star
PARAS, Indias First high efficiency stable
echelle spectrograph will be coupled to the Mt
Abu 1.2 telescope
PARAS Team includes Abhijit Chakraborty (PI), F.M
Pathan, Venkatramani, S Mahadevan (PSU), Harvey
Richardson (UBC), Arpita Rao, SAC PRL Engineers
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PARAS A stable Fiber Fed Echelle Spectrograph

• 80 nights per year guaranteed to planet search
  program with PARAS
• Median site seeing is 1arcsec. PARAS fiber on sky
  is 2.35 arcsec- so VERY efficient instrument.
• 150n/yr photometric, 250 clear night

PARAS coupled to the Mt Abu 1.2 m telescope
Instrument Commissioning on site Jan 2010
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PARAS A stable Fiber Fed Echelle Spectrograph

• PARAS is a R70k resolution Echelle spectrograph
• Comissioning Jan 2010
• Mt Abu 1.2 Telescope in India
• 370-850nm simultaneous coverage
• Th-Ar Calibration
• Fiber Fed
• White Pupil Design
• Prism Cross-Diperser

100 mm Beam R4 Grating
Chakraborty, Richardson Mahadevan, SPIE 2008
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PARAS A stable Fiber Fed Echelle Spectrograph
370 nm
850nm
Wide Simultaneous Wavelength Coverage with a 4k x
4k deep depletion e2v CCD. CaII HK-Ca NIR
Triplet coverage in one shot. PBM8Y prism has
low dn/dT (3 X 10 -6) minimizing temperature
shifts
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PARAS A stable Fiber Fed Echelle Spectrograph
PARAS will be enclosed in a vacuum vessel and
operated at 10-2 mbar for instrument
stability. Fully double scrambled fibers for high
RV accuracy Acknowledge very useful
discussons/input from F. Pepe, S. Udry Geneva Obs.
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PARAS A stable Fiber Fed Echelle Spectrograph
The main Optics are expected to arrive from SESO
(France) in late Nov 09.
Vacuum Chamber
Inside view
Prism
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PARAS A stable Fiber Fed Echelle Spectrograph
Prism
31.6g/mm R4 echelle grating in its storage
cell Camera systems from IR labs with a vibration
damping system to reduce cryotiger vibration
amplitude to 10nm
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PARAS A stable Fiber Fed Echelle Spectrograph
Dedicated Insulated Room has been constructed in
the Mt Abu observatory to house the PARAS
instrument Insulation and active temperature
control of room will maintain the instrument
temperature at 0.01 deg C around the set point of
25C
Prism
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PARAS A stable Fiber Fed Echelle Spectrograph
Include
Telescope F/13 to Fiber F/4 transfer optics
Telescope Focus Pinhole position
50micron Fiber Tip
Jacketed Fiber tip
F/4 Doublet
F/13 Doublet
Jacketed Fiber tip
Custom made fiber assembly by Polymicro has both
fibers in the same epoxy with a 180um space
between them. Monolithic assembly minimized
drifts between the star and calib fibers.
F/4 Doublet
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Dedicated 50cm Photometric Telescope
Include

• Dedicated 50 cm Photometric telescope will be
  available at the Mt Abu site by December 2009
• Equipped with a 4k x 4k front illuminated CCD
  (QE60 in V)
• FOV is 37 x 37 arcmin
• Will be useful for photometric monitoring of
  PARAS candidates, known transits, and wide field
  searches

PRL Exoplanet Programs are Supported by the Govt.
of India, Department of Space, and the PRL
director (J.N. Goswami)
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PARAS Dedicated 50cm Photometric Telescope
Include
Refining Ephemerids with RV and then searching
transit windows to find long period TRANSITING
planets around BRIGHT stars with KNOWN RV planets
see TERMS poster by Stephen Kane
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Science with ongoing Programs
Include
Complementary photometric capability along with
PARAS enables scientific programs like the search
for transits around long period exoplanets by
refining their transit windows with RV and then
observing with the 50cm telescope , and with
PARAS to detect the transit with photometry and
Rossiter McLaughlin. Also a good suite to confirm
candidate exoplanets around giant stars detected
with ongoing surveys like that at the HET. PARAS
red wavelengths useful to test concepts of radial
velocity extraction in presence of telluric
features. Essential test for future NIR
spectrographs. Possible follow-up and
confirmation of candidates from ongoing
multi-object RV surveys like SDSSIII MARVELS Long
term monitoring of bright stars to discover low
mass exoplanets. Stellar astrophysics studies
will also be enabled.
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Future Plans

• PARAS has been built to be very efficient and can
  be coupled to a future 2.5-3.5m telescope with
  very little additional slit losses
• Goal is to have a dedicated 2.5m robotic
  telescope for PARAS and for RV searches by 2015.
  Long term monitoring of bright stars ar high RV
  precision, followup and confirmation of long
  period candidates
• Longer term ideas for possible space missions in
  very preliminary discussion stage