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Stellar intensity interferometry over kilometer baselines: Laboratory simulation of observations with the Cherenkov Telescope Array

Dravins, Dainis LU and Lagadec, Tiphaine (2014) Conference on Optical and Infrared Interferometry IV In Optical and Infrared Interferometry IV 9146. p.91460-91460
Abstract
A long-held astronomical vision is to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, show their evolution over time, and reveal interactions of stellar winds and gas flows in binary star systems. An opportunity is now opening up with the large telescope arrays primarily erected for measuring Cherenkov light in air induced by gamma rays. With suitable software, such telescopes could be electronically connected and used also for intensity interferometry. With no optical connection between the telescopes, the error budget is set by the electronic time resolution of a few nanoseconds. Corresponding light-travel distances are on the order of... (More)
A long-held astronomical vision is to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, show their evolution over time, and reveal interactions of stellar winds and gas flows in binary star systems. An opportunity is now opening up with the large telescope arrays primarily erected for measuring Cherenkov light in air induced by gamma rays. With suitable software, such telescopes could be electronically connected and used also for intensity interferometry. With no optical connection between the telescopes, the error budget is set by the electronic time resolution of a few nanoseconds. Corresponding light-travel distances are on the order of one meter, making the method practically insensitive to atmospheric turbulence or optical imperfections, permitting both very long baselines and observing at short optical wavelengths. Theoretical modeling has shown how stellar surface images can be retrieved from such observations and here we report on experimental simulations. In an optical laboratory, artificial stars (single and double, round and elliptic) are observed by an array of telescopes. Using high-speed photon-counting solid-state detectors and real-time electronics, intensity fluctuations are cross correlated between up to a hundred baselines between pairs of telescopes, producing maps of the second-order spatial coherence across the interferometric Fourier-transform plane. These experiments serve to verify the concepts and to optimize the instrumentation and observing procedures for future observations with (in particular) CTA, the Cherenkov Telescope Array, aiming at order-of-magnitude improvements of the angular resolution in optical astronomy. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Intensity interferometry, Hanbury Brown - Twiss, Aperture synthesis, Second-order coherence, Stellar surface imaging, Exoplanet imaging, Cherenkov telescopes, Cherenkov Telescope Array
in
Optical and Infrared Interferometry IV
volume
9146
pages
91460 - 91460
publisher
SPIE
conference name
Conference on Optical and Infrared Interferometry IV
external identifiers
  • wos:000354379200031
  • scopus:84922754129
ISSN
0277-786X
1996-756X
DOI
10.1117/12.2055131
language
English
LU publication?
yes
id
94a9ef21-d177-4cf7-9755-adfc0011c0a7 (old id 7424941)
date added to LUP
2015-06-26 08:07:20
date last changed
2017-01-01 03:12:26
@inproceedings{94a9ef21-d177-4cf7-9755-adfc0011c0a7,
  abstract     = {A long-held astronomical vision is to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, show their evolution over time, and reveal interactions of stellar winds and gas flows in binary star systems. An opportunity is now opening up with the large telescope arrays primarily erected for measuring Cherenkov light in air induced by gamma rays. With suitable software, such telescopes could be electronically connected and used also for intensity interferometry. With no optical connection between the telescopes, the error budget is set by the electronic time resolution of a few nanoseconds. Corresponding light-travel distances are on the order of one meter, making the method practically insensitive to atmospheric turbulence or optical imperfections, permitting both very long baselines and observing at short optical wavelengths. Theoretical modeling has shown how stellar surface images can be retrieved from such observations and here we report on experimental simulations. In an optical laboratory, artificial stars (single and double, round and elliptic) are observed by an array of telescopes. Using high-speed photon-counting solid-state detectors and real-time electronics, intensity fluctuations are cross correlated between up to a hundred baselines between pairs of telescopes, producing maps of the second-order spatial coherence across the interferometric Fourier-transform plane. These experiments serve to verify the concepts and to optimize the instrumentation and observing procedures for future observations with (in particular) CTA, the Cherenkov Telescope Array, aiming at order-of-magnitude improvements of the angular resolution in optical astronomy.},
  author       = {Dravins, Dainis and Lagadec, Tiphaine},
  booktitle    = {Optical and Infrared Interferometry IV},
  issn         = {0277-786X},
  keyword      = {Intensity interferometry,Hanbury Brown - Twiss,Aperture synthesis,Second-order coherence,Stellar surface imaging,Exoplanet imaging,Cherenkov telescopes,Cherenkov Telescope Array},
  language     = {eng},
  pages        = {91460--91460},
  publisher    = {SPIE},
  title        = {Stellar intensity interferometry over kilometer baselines: Laboratory simulation of observations with the Cherenkov Telescope Array},
  url          = {http://dx.doi.org/10.1117/12.2055131},
  volume       = {9146},
  year         = {2014},
}