Mr. Edgar R. Ligon Profile

Edgar R. Ligon

Publications (25)

Proceedings Article | 26 August 2022 Presentation + Paper

Design of the new CHARA instrument SILMARIL: pushing for the sensitivity of a 3-beam combiner in the H- and K-bands

Cyprien Lanthermann, Theo ten Brummelaar, Peter Tuthill, Marc-Antoine Martinod, Edgar Ligon, Douglas Gies, Gail Schaefer, Matthew Anderson

Proceedings Volume 12183, 121830N (2022) https://doi.org/10.1117/12.2628268

KEYWORDS: Signal to noise ratio, K band, Stars, Sensors, Cameras, Optical filters, Spectral resolution, Interferometry, Device simulation

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Proceedings Article | 26 August 2022 Presentation + Paper

Recent technical and scientific highlights from the CHARA Array

Douglas Gies, Matthew Anderson, Narsireddy Anugu, Theo ten Brummelaar, Victor Castillo, Christopher Farrington, Steven Golden, Jeremy Jones, Robert Klement, Rainer Köhler, Cyprien Lanthermann, E. Robert Ligon, Olli Majoinen, Harold McAlister, Stephen Ridgway, Gail Schaefer, Nicholas Scott, Nils Turner, Norman Vargas, Larry Webster, Craig Woods

Proceedings Volume 12183, 1218303 (2022) https://doi.org/10.1117/12.2629048

KEYWORDS: Stars, Telescopes, Adaptive optics, Interferometry, K band, Planets, Spectroscopy, Exoplanets, Control systems, Spatial resolution

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Proceedings Article | 26 August 2022 Poster + Paper

The CHARA Michelson Array Pathfinder

R. Ligon, M. Anderson, N. Anugu, T. ten Brummelaar, C. Farrington, D. Gies, S. Golden, R. Koehler, F. Reynaud, S. Ridgway, G. Schaefer, N. Scott, L. Sturmann, N. Turner, C. Woods

Proceedings Volume 12183, 121832N (2022) https://doi.org/10.1117/12.2629530

KEYWORDS: Optical fibers, Telescopes, Optical instrument design, Adaptive optics

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Proceedings Article | 13 December 2020 Presentation + Paper

Setting the stage for first fringes with the Magdalena Ridge Observatory Interferometer

M. Creech-Eakman, V. Romero, C. Haniff, D. Buscher, J. Young, A. Olivares, E. Ligon, I. Payne, B. Avila, S. Blevins, N. Chowdhury, R. Collins, C. Dahl, D. Das Roy, J. Dooley, D. Etscorn, S. Etscorn, A. Farris, M. Fisher, E. Garcia, M. Gabaldon, C. Gino, R. Halder, O. Hosseini, B. Jaynes, L. Jencka, P. Johnston, S. Jojola, J. Luis, J. Maes, W. Martin, T. Matthews, C. McKeen, S. Mohammadi, D. Mortimer, S. Norouzi, D. Ochoa, B. Panta, J. Pino, I. Salayandia, C. Salcido, A. Sanchez, F. Santoro, E. B. Seneta, X. Sun, D. Wilson, J. Wolfram

Proceedings Volume 11446, 1144609 (2020) https://doi.org/10.1117/12.2563173

KEYWORDS: Interferometers, Magdalena Ridge Observatory, Telescopes, Infrared telescopes, Infrared imaging, Infrared radiation, Optical instrument design, Beam controllers, Control systems, Sensors

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Proceedings Article | 13 December 2020 Poster + Presentation + Paper

Deployment of beam alignment hardware at the Magdalena Ridge Observatory Interferometer

James J. Luis, David Buscher, Chuck Dahl, Jonathan Dooley, Allen Farris, Christopher Haniff, E. Robert Ligon, Siavash Norouzi, Xiaowei Sun, John Young

Proceedings Volume 11446, 1144628 (2020) https://doi.org/10.1117/12.2562863

KEYWORDS: Active optics, Magdalena Ridge Observatory, Interferometers, Optical alignment, Long baseline optical interferometry, Optical tracking, Telescopes, Visibility, Heart, Wavefront sensors

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Proceedings Article | 13 December 2020 Presentation + Paper

First laboratory results from FOURIER, the initial science combiner at the MROI

Daniel Mortimer, David Buscher, Michelle Creech-Eakman, Chris Haniff, Edgar Ligon, James Luis, Christopher Salcido, Eugene Seneta, Xiaowei Sun, John Young

Proceedings Volume 11446, 114460V (2020) https://doi.org/10.1117/12.2561472

KEYWORDS: Free space optics, K band, Interferometry, Magdalena Ridge Observatory, Interferometers, Sensors, Free space, Spatial filters

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Proceedings Article | 13 December 2020 Poster + Presentation + Paper

When you want it done right now: experience from programming hard real time systems in Xenomai for the Magdalena Ridge Observatory interferometer

Eugene Seneta, John Young, David Buscher, E. Robert Ligon, Dylan Etscorn, Allen Farris

Proceedings Volume 11452, 114521G (2020) https://doi.org/10.1117/12.2562191

KEYWORDS: Magdalena Ridge Observatory, Interferometers, Computer programming, Operating systems, Computing systems, Astronomy, Metrology, Laser metrology, Imaging systems, Electron multiplying charge coupled devices

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Proceedings Article | 9 July 2018 Paper

Towards integration of the Unit Telescope for the Magdalena Ridge Observatory interferometer

Andres Olivares, Fernando Santoro, Christopher Salcido, Robert Ligon, Chuck Dahl, Perry Johnston, Robert Blasi, Allen Farris, Dylan Etscorn, Michelle Creech-Eakman, Ifan Payne, John Young, Davide Marzotto, Olivier Pirnay

Proceedings Volume 10701, 107010P (2018) https://doi.org/10.1117/12.2312908

KEYWORDS: Telescopes, Interferometers, Mirrors, Magdalena Ridge Observatory, Optical alignment, Safety, Telecommunications, Cameras, Analytical research, Optical fabrication

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Proceedings Article | 9 July 2018 Presentation + Paper

The Magdalena Ridge Observatory interferometer: first light and deployment of the first telescope on the array

M. Creech-Eakman, V. Romero, I. Payne, C. Haniff, D. Buscher, J. Young, F. Santoro, R. Blasi, C. Dahl, J. Dooley, D. Etscorn, A. Farris, M. Fisher, E. Garcia, C. Gino, B. Jaynes, L. Jencka, P. Johnston, C. Jurgenson, R. Kelly, D. Klinglesmith, E. R. Ligon, J. Luis, T. McCracken, C. McKeen, D. Mortimer, D. Ochoa, A. Olivares, J. Pino, C. Salcido, L. Schmidt, E. Seneta, X. Sun, D. Wilson

Proceedings Volume 10701, 1070106 (2018) https://doi.org/10.1117/12.2314155

KEYWORDS: Telescopes, Space telescopes, Interferometers, Mirrors, Interferometry, Sensors, Relays, Optical instrument design, Magdalena Ridge Observatory, Reflector telescopes

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The Magdalena Ridge Observatory Interferometer (MROI) has been under development for almost two decades. Initial funding for the facility started before the year 2000 under the Army and then Navy, and continues today through the Air Force Research Laboratory. With a projected total cost of substantially less than $200M, it represents the least expensive way to produce sub-milliarcsecond optical/near-infrared images that the astronomical community could invest in during the modern era, as compared, for instance, to extremely large telescopes or space interferometers. The MROI, when completed, will be comprised of 10 x1.4m diameter telescopes distributed on a Y-shaped array such that it will have access to spatial scales ranging from about 40 milliarcseconds down to less than 0.5 milliarcseconds. While this type of resolution is not unprecedented in the astronomical community, the ability to track fringes on and produce images of complex targets approximately 5 magnitudes fainter than is done today represents a substantial step forward. All this will be accomplished using a variety of approaches detailed in several papers from our team over the years. Together, these two factors, multiple telescopes deployed over very long-baselines coupled with fainter limiting magnitudes, will allow MROI to conduct science on a wide range and statistically meaningful samples of targets. These include pulsating and rapidly rotating stars, mass-loss via accretion and mass-transfer in interacting systems, and the highly-active environments surrounding black holes at the centers of more than 100 external galaxies. This represents a subsample of what is sure to be a tremendous and serendipitous list of science cases as we move ahead into the era of new space telescopes and synoptic surveys. Additional investigations into imaging man-made objects will be undertaken, which are of particular interest to the defense and space-industry communities as more human endeavors are moved into the space environment.

In 2016 the first MROI telescope was delivered and deployed at Magdalena Ridge in the maintenance facility. Having undergone initial check-out and fitting the system with optics and a fast tip-tilt system, we eagerly anticipate installing the telescope enclosure in 2018. The telescope and enclosure will be integrated at the facility and moved to the center of the interferometric array by late summer of 2018 with a demonstration of the performance of an entire beamline from telescope to beam combiner table shortly thereafter. At this point, deploying two more telescopes and demonstrating fringe-tracking, bootstrapping and limiting magnitudes for the facility will prove the full promise of MROI. A complete status update of all subsystems follows in the paper, as well as discussions of potential collaborative initiatives.

Proceedings Article | 9 July 2018 Paper

The MROI fringe tracking system: camera hardware modifications to integrate the SAPHIRA detector

R. Ligon, C. Salcido, D. Buscher, M. Creech-Eakman, C. Haniff, F. Santoro, C. Jurgenson, T. McCracken, L. Schmidt, J. Young

Proceedings Volume 10701, 107010D (2018) https://doi.org/10.1117/12.2312673

KEYWORDS: Sensors, Spectrographs, Cameras, Optical alignment, Electronics, Monochromatic aberrations, Imaging systems, Tolerancing, Zemax, Interferometry

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Proceedings Article | 9 July 2018 Paper

Augmented design for a fully automated alignment system at the Magdalena Ridge Observatory Interferometer

James J. Luis, Robert Blasi, David Buscher, Allen Farris, Robert Kelly, Robert Ligon

Proceedings Volume 10701, 107010M (2018) https://doi.org/10.1117/12.2312549

KEYWORDS: Sensors, Beam splitters, Wavefront sensors, Telescopes, Mirrors, Light sources, Prototyping, Cameras, Photons, Interferometers

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Proceedings Article | 26 September 2013 Paper

Electric field conjugation with the project 1640 coronagraph

Eric Cady, Christoph Baranec, Charles Beichman, Douglas Brenner, Rick Burruss, Justin Crepp, Richard Dekany, David Hale, Lynne Hillenbrand, Sasha Hinkley, E. Robert Ligon, Thomas Lockhart, Ben Oppenheimer, Ian Parry, Laurent Pueyo, Emily Rice, Lewis Roberts, Jennifer Roberts, Michael Shao, Anand Sivaramakrishnan, Remi Soummer, Hong Tang, Tuan Truong, Gautam Vasisht, Fred Vescelus, J. Kent Wallace, Chengxing Zhai, Neil Zimmerman

Proceedings Volume 8864, 88640K (2013) https://doi.org/10.1117/12.2024635

KEYWORDS: Coronagraphy, Wavefronts, Iterated function systems, Stars, Telescopes, Cameras, Sensors, Adaptive optics, Wavefront sensors, Space telescopes

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Proceedings Article | 13 September 2012 Paper

A first order wavefront estimation algorithm for P1640 calibrator

C. Zhai, G. Vasisht, M. Shao, T. Lockhart, E. Cady, B. Oppenheimer, R. Burruss, J. Roberts, C. Beichman, D. Brenner, J. Crepp, R. Dekany, S. Hinkley, L. Hillenbrand, E. R. Ligon, I. Parry, L. Pueyo, E. Rice, L. Roberts, A. Sivaramakrishnan, R. Soummer, F. Vescelus, K. Wallace, N. Zimmerman

Proceedings Volume 8447, 84476W (2012) https://doi.org/10.1117/12.927015

KEYWORDS: Calibration, Wavefronts, Coronagraphy, Adaptive optics, Actuators, Imaging systems, Cameras, Speckle, Spatial frequencies, Wavefront sensors

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Proceedings Article | 13 September 2012 Paper

Project 1640: the world's first ExAO coronagraphic hyperspectral imager for comparative planetary science

Ben Oppenheimer, Charles Beichman, Douglas Brenner, Rick Burruss, Eric Cady, Justin Crepp, Lynne Hillenbrand, Sasha Hinkley, E. Ligon, Thomas Lockhart, Ian Parry, Laurent Pueyo, Emily Rice, Lewis Roberts, Jennifer Roberts, Michael Shao, Anand Sivaramakrishnan, Rémi Soummer, Gautam Vasisht, Fred Vescelus, J. Kent Wallace, Chengxing Zhai, Neil Zimmerman

Proceedings Volume 8447, 844720 (2012) https://doi.org/10.1117/12.926419

KEYWORDS: Stars, Adaptive optics, Coronagraphy, Planets, Wavefronts, Speckle, Sensors, Imaging systems, Control systems, Telescopes

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Proceedings Article | 28 July 2008 Paper

Keck Interferometer nuller update

M. M. Colavita, E. Serabyn, A. J. Booth, S. L. Crawford, J. I. Garcia-Gathright, E. R. Ligon, B. L. Mennesson, C. G. Paine, P. L. Wizinowich, S. Ragland, E. C. Appleby, B. C. Berkey, A. Cooper, W. Dahl, J. T. Gathright, M. A. Hrynevych, D. W. Medeiros, D. Morrison, T. Panteleeva, B. Smith, K. R. Summers, K. Tsubota, C. Tyau, E. Wetherell, J. M. Woillez, R. L. Akeson, R. Millan-Gabet, C. Felizardo, C. D. Koresko, J. S. Herstein

Proceedings Volume 7013, 70130A (2008) https://doi.org/10.1117/12.789476

KEYWORDS: Nulling interferometry, Signal to noise ratio, Interferometers, Cameras, Calibration, Stars, Telescopes, Phase shift keying, K band, Modulation

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Proceedings Article | 28 July 2008 Paper

Recent progress at the Keck Interferometer: operations and V2 science

S. Ragland, P. Wizinowich, R. Akeson, M. Colavita, E. Appleby, B. Berkey, A. Booth, A. Cooper, S. Crawford, W. Dahl, C. Felizardo, J. Garcia-Gathright, J. Herstein, M. Hrynevych, C. Koresko, R. Ligon, D. Medeiros, B. Mennesson, R. Millan-Gabet, D. Morrison, C. Paine, B. Parvin, T. Panteleeva, E. Serabyn, B. Smith, K. Summers, K. Tsubota, C. Tyau, E. Wetherell, J. Woillez

Proceedings Volume 7013, 70130B (2008) https://doi.org/10.1117/12.788070

KEYWORDS: Nulling interferometry, Stars, Cameras, Telescopes, Interferometers, Adaptive optics, Visibility, Mirrors, L band, Cryogenics

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Proceedings Article | 28 June 2006 Paper

Science observations with the Keck Interferometer Nuller

E. Serabyn, A. Booth, M. Colavita, S. Crawford, J. Garcia, J. Gathright, M. Hrynevych, C. Koresko, R. Ligon, B. Mennesson, T. Panteleeva, S. Ragland, K. Summers, W. Traub, K. Tsubota, E. Wetherell, P. Wizinowich, J. Woillez

Proceedings Volume 6268, 626815 (2006) https://doi.org/10.1117/12.672621

KEYWORDS: Nulling interferometry, Stars, Interferometers, Visibility, Remote sensing, Adaptive optics, Cameras, Keck Observatory, K band, Data modeling

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Proceedings Article | 28 June 2006 Paper

Picometer differential-phase measurements in the laboratory

Gautam Vasisht, E. Robert Ligon, Erik Bloemhof, M. Mark Colavita

Proceedings Volume 6268, 62682X (2006) https://doi.org/10.1117/12.672619

KEYWORDS: Interferometers, Calibration, Modulation, Optical fibers, Modulators, Sensors, Stars, Phase measurement, Cameras, Beam splitters

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Proceedings Article | 27 June 2006 Paper

Recent progress at the Keck Interferometer

Peter Wizinowich, Rachel Akeson, Mark Colavita, John Gathright, Eric Appleby, Jim Bell, Ben Berkey, Andrew Booth, Heidi Brandenburg, Jason Chin, Wayne Dahl, Claude Felizardo, Jean Garcia, Scott Hartman, Jen Herstein, Michael Hrynevych, Chris Koresko, Robert Ligon, Rafael Millan-Gabet, Doug Morrison, Tatyana Panteleeva, Sam Ragland, Robert Smythe, Kellee Summers, Kevin Tsubota, Colette Tyau, Ed Wetherell, Julien Woillez

Proceedings Volume 6268, 62680N (2006) https://doi.org/10.1117/12.672069

KEYWORDS: Interferometers, Adaptive optics, Cameras, Mirrors, Telescopes, Nulling interferometry, Visibility, Data archive systems, Calibration, Stars

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Proceedings Article | 15 September 2005 Paper

Final laboratory integration and test of the Keck Interferometer nuller

S. Crawford, M. Colavita, J. Garcia, E. Ligon, B. Mennesson, C. Paine, E. Serabyn, R. Smythe, M. Swain, G. Vasisht

Proceedings Volume 5905, 59050U (2005) https://doi.org/10.1117/12.619131

KEYWORDS: Nulling interferometry, Interferometers, Mid-IR, Cameras, Beam splitters, Sensors, Stars, Exoplanets, Planets, Colorimetry

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Proceedings Article | 15 September 2005 Paper

The Keck interferometer nuller (KIN): configuration, measurement approach, and first results

E. Serabyn, E. Appleby, J. Bell, A. Booth, J. Chin, M. Colavita, S. Crawford, M. Creech-Eakman, W. Dahl, J. Fanson, J. Garcia, J. Gathright, E. Hovland, M. Hrynevych, C. Koresko, R. Ligon, B. Mennesson, J. Moore, D. Palmer, T. Panteleeva, C. Paine, S. Ragland, L. Reder, T. Saloga, R. Smythe, C. Tyau, K. Tsubota, G. Vasisht, E. Wetherell, P. Wizinowich, J. Woillez

Proceedings Volume 5905, 59050T (2005) https://doi.org/10.1117/12.618228

KEYWORDS: Nulling interferometry, Metrology, Beam splitters, Near infrared, Cameras, Stars, Mirrors, Interferometers, K band, Keck Observatory

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Proceedings Article | 20 October 2004 Paper

The Keck interferometer nuller: system architecture and laboratory performance

Eugene Serabyn, Andrew Booth, M. Colavita, Michelle Creech-Eakman, Samuel Crawford, Jean Garcia, Richard Johnson, Erik Hovland, C. Koresko, Edgar Ligon, Stefan Martin, Bertrand Mennesson, James Moore, Dean Palmer, Christopher Paine, Michael Shao, Mark Swain, Robert Smythe, Gautam Vasisht

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.552195

KEYWORDS: Nulling interferometry, Beam splitters, Metrology, Interferometers, Cameras, Stars, Mid-IR, Keck Observatory, Interferometry, Signal detection

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Proceedings Article | 20 October 2004 Paper

Baseline monitoring for astrometric interferometry

Michael Hrynevych, Edgar Ligon, M. Colavita

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.552320

KEYWORDS: Telescopes, Space telescopes, Cameras, Stars, Motion measurement, Interferometers, Interferometry, Laser metrology, Retroreflectors, Mirrors

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Proceedings Article | 21 February 2003 Paper

Keck Interferometer autoaligner

Gerard van Belle, M. Mark Colavita, Edgar Ligon, James Moore, Dean Palmer, Leonard Reder, Robert Smythe

Proceedings Volume 4838, (2003) https://doi.org/10.1117/12.459325

KEYWORDS: Interferometers, Telescopes, Light emitting diodes, Mirrors, Actuators, Optical alignment, Optical components, CCD cameras, Cameras, Automatic alignment

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Proceedings Article | 21 February 2003 Paper

Performance and verification of the Keck Interferometer fringe detection and tracking system

Gautam Vasisht, Andrew Booth, M. Mark Colavita, Richard Johnson, Edgar Ligon, James Moore, Dean Palmer

Proceedings Volume 4838, (2003) https://doi.org/10.1117/12.456779

KEYWORDS: Interferometers, Cameras, Stars, Signal to noise ratio, Control systems, Servomechanisms, Electronics, Staring arrays, Adaptive optics, K band

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Showing 5 of 25 publications

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