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Interferometry at Altitude : Galaxies, Stars, and Exoplanets. BETTII, BENI, and Other Fantastical Notions. With contributions from R. Lyon (BENI PI), the BENI team , and the BETTII team. Motivation. Angular Resolution! Contrast (nulling). Design. How Does it Work?.
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Interferometry at Altitude:Galaxies, Stars, and Exoplanets BETTII, BENI, and Other Fantastical Notions With contributions from R. Lyon (BENI PI), the BENI team, and the BETTII team
Motivation • Angular Resolution! • Contrast (nulling) S. Rinehart Interferometry at Altitude
Design S. Rinehart Interferometry at Altitude
How Does it Work? • Observe at different times to get sky rotation • Enables accurate derivation of relative positions • Effective resolution of ~0.5 arcsec • By stroking the delay line, we obtain fringe packets • Can derive the spectrum of the sources from the fringes • Spatially-Resolved Spectroscopy S. Rinehart Interferometry at Altitude
BETTII Science I Star formation: • Does star formation in clusters differ from that in isolated regions? • What FIR emission arises from disks of individual sources? From inner envelopes? S. Rinehart Interferometry at Altitude
BETTII Science II Active Galactic Nuclei: • What are the energetics in the core of an AGN? • How do different regions contribute to the FIR flux? S. Rinehart Interferometry at Altitude
What is BENI? • Fizeau interferometry • 3 10-cm collectors • 1.5 meter baseline • Visible Nulling Interferometer • Technologically challenging • Reactionless payload tracking • Fine pointing with 3 FSMs • Active wavefront control The VNC Testbed: BENI on a Bench S. Rinehart Interferometry at Altitude
Visible Nulling • Mach-Zehnder Interferometer • Light split at first beamsplitter • Recombined at second • Combine beams from 3 telescopes (Fizeau) • Arm #1: Catseye reflector (flips image and rotates polarization 180°) • Arm #2; deformable mirror (feedback from bright output) S. Rinehart Interferometry at Altitude
BENI Science I Exoplanets • Image a debris disk • Exozodiacal Light • Hidden planets? Directly image a Jovian planet S. Rinehart Interferometry at Altitude
BENI Science II • Characterize the high altitude atmosphere • Turbulence • Scintillation • Greenwood frequency • Estimates made via modeling now indicate: • Turbulence: ro > 50m • Scintillation < 0.1% • fG << 1 Hz S. Rinehart Interferometry at Altitude
Follow-on There’s great science with BETTII, and her daughters (longer booms, cold telescopes, nulling, moveable siderostats…..) will be able to do even more! The same is true for BENI; could we do spectroscopy of exoplanets on a balloon? Both also pave the way for potential space missions… S. Rinehart Interferometry at Altitude
Thanks The BETTII Team: S. Rinehart1 (PI), C. Allen1, R. Barry1, D. Benford, W. Danchi1, D. Fixsen2, D. Leisawitz1, L. Mundy2, R. Silverberg1, J. Staguhn2, A. Kogut1, R. Lyon1, J. Mather1 The BENI Team: R. Lyon1, M. Clampin1, J. Herman1, S. Rinehart1, K. Carpenter1, H. Ford3, L. Petro4, G. Vasudevan5, R. Woodruff5, J. Marzouk6, P. Petrone6 1: GSFC 2: UMCP 3: JHU 4: STScI 5: Lockheed-Martin 6: Sigma Space S. Rinehart Interferometry at Altitude