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Fringe Tracking at the IOTA Interferometer

by John D. Monnierb, Sam Ragl, Nathaniel P. Carletona, F. P. Schloerbg, M. K. Brewerg, J-p. Bergerh, Marc G. Lacassea
"... We describe the fringe–packet tracking software installed at the infrared optical telescope array (IOTA). Three independently developed fringe–packet tracking algorithms can be used to equalise the optical path lengths at the interferometer. We compare the performance of these three algorithms and s ..."
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We describe the fringe–packet tracking software installed at the infrared optical telescope array (IOTA). Three independently developed fringe–packet tracking algorithms can be used to equalise the optical path lengths at the interferometer. We compare the performance of these three algorithms

The Astrophysical Journal Letters, 742:L1 (6pp), 2011 November 20 doi:10.1088/2041-8205/742/1/L1 C © 2011. The American Astronomical Society. All rights reserved. Printed in the U.S.A. FIRST VISUAL ORBIT FOR THE PROTOTYPICAL COLLIDING-WIND BINARY WR 140

by J. D. Monnier, Ming Zhao, E. Pedretti, R. Millan-gabet, J. -p. Berger, W. Traub, F. P. Schloerb, T. Ten Brummelaar, H. Mcalister, S. Ridgway, L. Sturmann, J. Sturmann, N. Turner, F. Baron, S. Kraus, A. Tannirkulam, P. M. Williams
"... Wolf–Rayet (WR) stars represent one of the final stages of massive stellar evolution. Relatively little is known about this short-lived phase and we currently lack reliable mass, distance, and binarity determinations for a representative sample. Here we report the first visual orbit for WR 140 ( = H ..."
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( = HD193793), a WC7 + O5 binary system known for its periodic dust production episodes triggered by intense colliding winds near periastron passage. The Infrared-Optical Telescope Array and Center for High Angular Resolution Astronomy interferometers resolved the pair of stars in each year from 2003

Submitted to EURASIP Journal on Applied Signal Processing, special issue on Applications of Signal Processing in Astrophysics and Cosmology Adaptive DFT-based interferometer fringe tracking

by Edward Wilson *a, Ettore Pedretti Bc, Jesse Bregman D, Robert W. Mah D, Wesley A. Traub B , 2004
"... An automatic interferometer fringe tracking system has been developed, implemented, and tested at the Infrared Optical Telescope Array (IOTA) observatory at Mt. Hopkins, Arizona. The system can minimize the optical path differences (OPDs) for all three baselines of the Michelson stellar interferomet ..."
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An automatic interferometer fringe tracking system has been developed, implemented, and tested at the Infrared Optical Telescope Array (IOTA) observatory at Mt. Hopkins, Arizona. The system can minimize the optical path differences (OPDs) for all three baselines of the Michelson stellar

LLiST- a new star tracker camera for tip-tilt correction at IOTA ∗

by P. A. Schuller A, M. G. Lacasse B, D. Lydon C, W. H. Mcgonagle D, E. Pedretti E, R. K. Reich D, F. P. Schloerb C, W. A. Traub A , 2004
"... The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests c ..."
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The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests

FIRST VISUAL ORBIT FOR THE PROTOTYPICAL COLLIDING-WIND BINARY WR 140

by J. D. Monnier, Ming Zhao, E. Pedretti, R. Millan-gabet, J. -p. Berger, W. Traub, F. P. Schloerb, T. Ten Brummelaar, H. Mcalister, S. Ridgway, L. Sturmann, J. Sturmann, N. Turner, F. Baron, S. Kraus, A. Tannirkulam, P. M. Williams - THE ASTROPHYSICAL JOURNAL LETTERS, 742:L1 (6PP), 2011 , 2011
"... Wolf–Rayet (WR) stars represent one of the final stages of massive stellar evolution. Relatively little is known about this short-lived phase and we currently lack reliable mass, distance, and binarity determinations for a representative sample. Here we report the first visual orbit for WR 140 ( = H ..."
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( = HD193793), a WC7 + O5 binary system known for its periodic dust production episodes triggered by intense colliding winds near periastron passage. The Infrared-Optical Telescope Array and Center for High Angular Resolution Astronomy interferometers resolved the pair of stars in each year from 2003

Sub--Astronomical Unit Structure Of The Near-Infrared Emission From Ab Aurigae

by Millan-Gabet And Schloerb, R. Millan-gabet, F. P. Schloerb, W. A. Traub, F. Malbet, J. P. Berger, J. D. Bregman
"... We present near-infrared, long-baseline, interferometric observations of AB Aurigae, a well-known Herbig Ae/ Be star, obtained with the Infrared Optical Telescope Array. The near-infrared emission from this source has been spatially resolved for the first time, and the observations indicate a char ..."
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We present near-infrared, long-baseline, interferometric observations of AB Aurigae, a well-known Herbig Ae/ Be star, obtained with the Infrared Optical Telescope Array. The near-infrared emission from this source has been spatially resolved for the first time, and the observations indicate a

Robust determination of optical path difference: fringe tracking at the IOTA interferometer

by Ettore Pedretti, Wesley A. Traub, John D. Monnier, Nathaniel P. Carleton, F. Peter Schloerb, Michael K. Brewer, Marc G. Lacasse, Sam Ragl, Ettore Pedretti, Wesley A. Traub, Sam Ragl, Nathaniel P. Carleton, Marc G. Lacasse, Usa John Monnier, Ettore Pedretti , 2005
"... We describe the fringe packet tracking system used to equalise the optical path lengths at the Infrared Optical Telescope Array (IOTA) interferometer. The measurement of closure phases requires obtaining fringes on three baselines simultaneously. This is accomplished using an algorithm based on doub ..."
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We describe the fringe packet tracking system used to equalise the optical path lengths at the Infrared Optical Telescope Array (IOTA) interferometer. The measurement of closure phases requires obtaining fringes on three baselines simultaneously. This is accomplished using an algorithm based

Adaptive DFT-based fringe tracking and prediction at IOTA

by Edward Wilson *a, Ettore Pedretti Bc, Jesse Bregman D, Robert W. Mah D, Wesley A. Traub B
"... An automatic fringe tracking system has been developed and implemented at the Infrared Optical Telescope Array (IOTA). In testing during May 2002, the system successfully minimized the optical path differences (OPDs) for all three baselines at IOTA. Based on sliding window discrete Fourier transform ..."
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An automatic fringe tracking system has been developed and implemented at the Infrared Optical Telescope Array (IOTA). In testing during May 2002, the system successfully minimized the optical path differences (OPDs) for all three baselines at IOTA. Based on sliding window discrete Fourier

Cepheid observations by long-baseline interferometry with FLUOR/IOTA

by V. Coudé Du Forestob, W. A. Traub C, M. G. Lacasse C
"... We report interferometric observations of the classical galactic Cepheid ζ Gem with FLUOR (Fiber Linked Unit for Optical Recombination), installed at the IOTA (Infrared Optical Telescope Array) interferometer. Thanks to the high precision of the visibility measurements with FLUOR, it has been possib ..."
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We report interferometric observations of the classical galactic Cepheid ζ Gem with FLUOR (Fiber Linked Unit for Optical Recombination), installed at the IOTA (Infrared Optical Telescope Array) interferometer. Thanks to the high precision of the visibility measurements with FLUOR, it has been

CPLD-Controlled PICNIC Camera at IOTA

by E. Pedretti, R. Millan-gabet, J. D. Monnier, W. A. Traub, N. P. Carleton, F. P. Schloerb, M. K. Brewer
"... We describe a new near-infrared camera based on the PICNIC array for the Infrared-Optical Telescope Array (IOTA). The camera control is based on a com-plex programmable logic device (CPLD). This architecture allows fast and stable clocking of the PICNIC array, resulting in faster and lower-noise rea ..."
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We describe a new near-infrared camera based on the PICNIC array for the Infrared-Optical Telescope Array (IOTA). The camera control is based on a com-plex programmable logic device (CPLD). This architecture allows fast and stable clocking of the PICNIC array, resulting in faster and lower
Results 1 - 10 of 4,117