Title of article :
Optical intensity interferometry with the Cherenkov Telescope Array
Author/Authors :
Dravins، نويسنده , , Dainis and LeBohec، نويسنده , , Stephan and Jensen، نويسنده , , Hannes and Nuٌez، نويسنده , , Paul D.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2013
Pages :
17
From page :
331
To page :
347
Abstract :
With its unprecedented light-collecting area for night-sky observations, the Cherenkov Telescope Array (CTA) holds great potential for also optical stellar astronomy, in particular as a multi-element intensity interferometer for realizing imaging with sub-milliarcsecond angular resolution. Such an order-of-magnitude increase of the spatial resolution achieved in optical astronomy will reveal the surfaces of rotationally flattened stars with structures in their circumstellar disks and winds, or the gas flows between close binaries. Image reconstruction is feasible from the second-order coherence of light, measured as the temporal correlations of arrival times between photons recorded in different telescopes. This technique (once pioneered by Hanbury Brown and Twiss) connects telescopes only with electronic signals and is practically insensitive to atmospheric turbulence and to imperfections in telescope optics. Detector and telescope requirements are very similar to those for imaging air Cherenkov observatories, the main difference being the signal processing (calculating cross correlations between single camera pixels in pairs of telescopes). Observations of brighter stars are not limited by sky brightness, permitting efficient CTA use during also bright-Moon periods. While other concepts have been proposed to realize kilometer-scale optical interferometers of conventional amplitude (phase-) type, both in space and on the ground, their complexity places them much further into the future than CTA, which thus could become the first kilometer-scale optical imager in astronomy.
Keywords :
Cherenkov telescopes , Hanbury Brown–Twiss , Stars: individual , Optical interferometry , Photon statistics , Intensity interferometry
Journal title :
Astroparticle Physics
Serial Year :
2013
Journal title :
Astroparticle Physics
Record number :
1336287
Link To Document :
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