Dr. John E. Krist Profile

Dr. John E. Krist

Research Scientist at Jet Propulsion Lab

SPIE Involvement:

Author

Publications (99)

SPIE Journal Paper | 11 October 2023 Open Access

Open Access

End-to-end numerical modeling of the Roman Space Telescope coronagraph

John Krist, John Steeves, Brandon Dube, A.J. Eldorado Riggs, Brian Kern, David Marx, Eric Cady, Hanying Zhou, Ilya Poberezhskiy, Caleb Baker, James McGuire, Bijan Nemati, Gary Kuan, Bertrand Mennesson, John Trauger, Navtej Saini, Sergi Hildebrandt Rafels

JATIS, Vol. 9, Issue 04, 045002, (October 2023) https://doi.org/10.1117/12.10.1117/1.JATIS.9.4.045002

KEYWORDS: Coronagraphy, Actuators, Space telescopes, Numerical modeling, Wavefronts, Modeling, Stars, Monochromatic aberrations, Polarization, Simulations

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Proceedings Article | 6 October 2023 Presentation

Presentation

End-to-end numerical modeling of the Roman Space Telescope Coronagraphic Instrument

John Krist, John Steeves, Navtej Saini, Brandon Dube, David Arndt

Proceedings Volume 12680, 126800U (2023) https://doi.org/10.1117/12.2677110

KEYWORDS: Space telescopes, Numerical modeling, Equipment, Coronagraphy, Modeling, Wavefronts, Telecommunications, Wavefront errors, Vibration, Systems modeling

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Proceedings Article | 5 October 2023 Presentation + Paper

Presentation + Paper

Nancy Grace Roman Space Telescope coronagraph instrument overview and status

Vanessa Bailey, Eduardo Bendek, Brian Monacelli, Caleb Baker, Gasia Bedrosian, Eric Cady, Ewan Douglas, Tyler Groff, Sergi Hildebrandt, N. Jeremy Kasdin, John Krist, Bruce Macintosh, Bertrand Mennesson, Patrick Morrissey, Ilya Poberezhskiy, Hari Subedi, Jason Rhodes, Aki Roberge, Marie Ygouf, Robert Zellem, Feng Zhao, Neil Zimmerman

Proceedings Volume 12680, 126800T (2023) https://doi.org/10.1117/12.2679036

KEYWORDS: Coronagraphy, Equipment, Mirrors, Optical benches, Wavefront sensors, Deformable mirrors, Cameras, Prisms, Observatories, Wavefront errors

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Proceedings Article | 5 October 2023 Poster + Paper

Poster + Paper

Roman coronagraph HOWFSC modeling: case study and raw contrast performance prediction

Hanying Zhou, Brian Kern, Nathan Bush, John Krist, Ilya Poberezhskiy

Proceedings Volume 12680, 1268027 (2023) https://doi.org/10.1117/12.2681773

KEYWORDS: Modeling, Coronagraphy, Calibration, Data modeling, Wavefront sensors, Vacuum, Risk assessment, Optical actuators, Astronomical detectors, Nonlinear control

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Proceedings Article | 5 October 2023 Poster + Paper

Poster + Paper

Coronagraph design survey for future exoplanet direct imaging space missions: interim update

Ruslan Belikov, Christopher Stark, Nick Siegler, Emiel Por, Bertrand Mennesson, Pin Chen, Kevin Fogarty, Olivier Guyon, Roser Juanola-Parramon, John Krist, Dimitri Mawet, Camilo Mejia Prada, Jeremy Kasdin, Laurent Pueyo, Susan Redmond, Garreth Ruane, Dan Sirbu, Karl Stapelfeldt, John Trauger, Neil Zimmerman

Proceedings Volume 12680, 126802G (2023) https://doi.org/10.1117/12.2677732

KEYWORDS: Coronagraphy, Design and modelling, Telescopes, Equipment, Exoplanets, Observatories, Wavefronts, Yield improvement, Planets

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SPIE Journal Paper | 27 September 2023

Analytical performance model and error budget for the Roman coronagraph instrument

Bijan Nemati, John Krist, Ilya Poberezhskiy, Brian Kern

JATIS, Vol. 9, Issue 03, 034007, (September 2023) https://doi.org/10.1117/12.10.1117/1.JATIS.9.3.034007

KEYWORDS: Stars, Analytic models, Planets, Error analysis, Coronagraphy, Sensors, Performance modeling, Speckle, Signal to noise ratio, Calibration

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The Nancy Grace Roman Space Telescope (“Roman”), under development by NASA, will investigate possible causes for the phenomenon of dark energy and detect and characterize extrasolar planets. The 2.4 m space telescope has two main instruments: a wide-field, infrared imager and a coronagraph. The coronagraph instrument (CGI) is a technology demonstrator designed to help bridge the gap between the current state-of-the-art space and ground instruments and future high-contrast space coronagraphs that will be capable of detecting and characterizing Earth-like planets in the habitable zones of other stars. Using adaptive optics, including two high-density deformable mirrors and low- and high-order wavefront sensing and control, CGI is designed to suppress the star light by up to nine orders of magnitude, potentially enabling the direct detection and characterization of Jupiter-class exoplanets. Contrast is the measure of starlight suppression, and high contrast is the chief virtue of a coronagraph. But it is not the only important characteristic: contrast must be balanced against acceptance of planet light. The remaining unsuppressed starlight must also have a stable morphology to allow further estimation and subtraction. To achieve all these goals in the presence of the disturbance and radiation environment of space, the coronagraph must be designed and fabricated as a highly optimized system. The CGI error budget is the top-level tool used to guide the optimization, enabling trades of various competing errors. The error budget is based on an analytical model, which enables rapid calculation and tracking of performance for the numerous and diverse questions that arise in the system engineering process. We outline the coronagraph system engineering approach and the error budget. We then describe in detail the analytical model for direct imaging and spectroscopy and show how it connects to the error budget. We introduce a number of useful ancillary metrics that provide insight into the capabilities of the instrument. Since models always need to be validated, we describe the validation approach for the CGI analytical model.

Proceedings Article | 27 August 2022 Presentation + Paper

Presentation + Paper

The Roman Space Telescope coronagraph technology demonstration: current status and relevance to future missions

B. Mennesson, V. Bailey, R. Zellem, S. Hildebrandt, M. Ygouf, J. Rhodes, N. Zimmerman, B. Nemati, G. Gonzalez, E. Cady, B. Kern, T. Koch, J. Krist, K. Heydorff, T. Luchik, F. Mok, P. Morrissey, I. Poberezhskiy, A. Riggs, F. Shi, F. Zhao, R. Akeson, L. Armus, A. Greenbaum, J. Ingalls, P. Lowrance

Proceedings Volume 12180, 121801W (2022) https://doi.org/10.1117/12.2629176

KEYWORDS: Coronagraphy, Wavefront sensors, Electron multiplying charge coupled devices, Imaging spectroscopy, Wavefronts, Stars, Spectroscopy, Performance modeling, Cameras, Observatories

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Proceedings Article | 27 August 2022 Presentation + Paper

Presentation + Paper

Roman coronagraph instrument: engineering overview and status

Ilya Poberezhskiy, Kathryn Heydorff, Thomas Luchik, Feng Zhao, Eric Cady, Gasia Bedrosian, Mark Colavita, Brandon Creager, Renaud Goullioud, Tyler Groff, Amanda Grue, Brian Monacelli, Patrick Morrissey, Joshua Kempenaar, Brian Kern, Matthew King, Timothy Koch, John Krist, Gary Kuan, Jonathan Lam, Dorothy Lewis, Fai Mok, David Muliere, Bijan Nemati, Charley Noecker, Jeffrey Oseas, A.J. Riggs, Fang Shi, Belinda Shreckengost

Proceedings Volume 12180, 121801X (2022) https://doi.org/10.1117/12.2630540

KEYWORDS: Coronagraphy, Electronics, Cameras, Interfaces, Mirrors, Control systems, Optical alignment, Observatories, Space operations, Optical benches

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Proceedings Article | 27 August 2022 Poster + Presentation + Paper

Poster + Presentation + Paper

JWST/NIRCam coronagraphy: commissioning and first on-sky results

Julien Girard, Jarron Leisenring, Jens Kammerer, Mario Gennaro, Marcia Rieke, John Stansberry, Armin Rest, Eiichi Egami, Ben Sunnquist, Martha Boyer, Alicia Canipe, Matteo Correnti, Bryan Hilbert, Marshall Perrin, Laurent Pueyo, Remi Soummer, Marsha Allen, Howard Bushouse, Jonathan Aguilar, Brian Brooks, Dan Coe, Audrey DiFelice, David Golimowski, George Hartig, Dean Hines, Anton Koekemoer, Bryony Nickson, Nikolay Nikolov, Vera Kozhurina-Platais, Nor Pirzkal, Massimo Robberto, Anand Sivaramakrishnan, Sangmo Tony Sohn, Randal Telfer, Chi Rai Wu, Thomas Beatty, Michael Florian, Kevin Hainline, Doug Kelly, Karl Misselt, Everett Schlawin, Fengwu Sun, Christina Williams, Christopher Willmer, Christopher Stark, Marie Ygouf, Aarynn Carter, Charles Beichman, Thomas Greene, Thomas Roellig, John Krist, Jéa Adams Redai, Jason Wang, Charles Clark, Dan Lewis, Malcolm Ferry

Proceedings Volume 12180, 121803Q (2022) https://doi.org/10.1117/12.2629636

KEYWORDS: Coronagraphy, Stars, James Webb Space Telescope, Point spread functions, Distortion, Telescopes, Signal to noise ratio, Calibration, Target acquisition, Exoplanets, Astronomical imaging, Near infrared, Direct methods, Astronomical instrumentation

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SPIE Journal Paper | 19 July 2022 Open Access

Open Access

Modeling and performance analysis of the LUVOIR coronagraph instrument

Roser Juanola-Parramon, Neil Zimmerman, Laurent Pueyo, Matthew Bolcar, Qian Gong, Tyler Groff, John Krist, Aki Roberge, Garreth Ruane, Christopher Stark

JATIS, Vol. 8, Issue 03, 034001, (July 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.3.034001

KEYWORDS: Coronagraphy, Wavefronts, Mirrors, Telescopes, Performance modeling, Stars, Instrument modeling, Planets, Exoplanets, Point spread functions

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SPIE Journal Paper | 16 March 2022

Dark hole maintenance with modal pairwise probing in numerical simulations of Roman coronagraph instrument

Leonid Pogorelyuk, John Krist, Bijan Nemati, A. J. Eldorado Riggs, Sam Miller, Laurent Pueyo, N. Jeremy Kasdin, Kerri Cahoy

JATIS, Vol. 8, Issue 01, 019002, (March 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.1.019002

KEYWORDS: Stars, Wavefronts, Numerical simulations, Sensors, Coronagraphy, Error analysis, Telescopes, Polarization, Electron multiplying charge coupled devices, Speckle

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We propose an efficient approach for focal-plane wavefront estimation for high-contrast imaging. It is designed for very low photon flux regimes with the Roman Space Telescope Coronagraph Instrument in mind. During days-long exposures of Roman, the starlight wavefront will drift due to the thermal instabilities of the optical tube assembly (OTA) and deformable mirror (DM) actuators. To correct the drift in high-order spatial wavefront modes, Roman will periodically be pointed to a bright reference star to sense the speckles in the dark hole (the high-contrast region of the image) and correct them. However, this maneuver decreases observation time by several hours a day and may lead to wavefront instability by causing structural and thermal stresses on the OTA. Instead, we propose maintaining the dark hole using the DM to modulate (probe) the speckles while observing the target star. Our proposed algorithm can then be used to directly estimate the DM commands that would create such speckles, rather than first estimating the electric field of the speckles. Applying the opposite commands on the DM reduces the intensity of the speckles without slewing to the reference star. Further, we analyze this dark-hole maintenance approach using data from Roman Observing Scenario 9 (OS9) simulations while assuming that the high-order wavefront control on Roman will be carried out from the Earth (ground-in-the-loop). In our simulations of Roman’s Hybrid Lyot Coronagraph, the high-order wavefront errors were sensed and corrected while observing a dim target, 47 UMa. Despite the DM probes, the photon flux in the dark hole remained close to that in OS9 and well below detector noise. In terms of planet-detectability, dark hole maintenance kept the post-processing contrast within 10% of OS9’s, even after pointing the telescope at the target star for 6 days. The OTA stability that dark hole maintenance provides compared to slewing the telescope potentially outweighs the small negative impact it has on the contrast.

Proceedings Article | 1 September 2021 Presentation + Paper

Presentation + Paper

The Roman Space Telescope coronagraph technology demonstration: current status and relevance to future missions

B. Mennesson, V. P. Bailey, R. Zellem, N. Zimmerman, M. Ygouf, S. Hildebrandt, J. Rhodes, J. Kasdin, B. Macintosh, M. Turnbull, E. Douglas, A. Mandell, B. Nemati, G. Gonzalez, E. Cady, B. Kern, J. Krist, F. Shi, F. Mok, P. Morrissey, K. Heydorff, I. Pobereszhskiy, F. Zhao, T. Luchik, E. Maier, R. Akeson, L. Armus, J. Ingalls, P. Lowrance, T. Meshkat

Proceedings Volume 11823, 1182310 (2021) https://doi.org/10.1117/12.2603343

KEYWORDS: Coronagraphy, Electron multiplying charge coupled devices, Wavefront sensors, Cameras, Wavefronts, Imaging spectroscopy, Stars, Imaging systems, Spectroscopy, Polarimetry

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Proceedings Article | 5 August 2021 Presentation

Presentation

Numerical Simulation of Dark Hole Maintenance and its Impact on Planet Detection for Roman Coronagraph Instrument Based on OS 9

Leonid Pogorelyuk, John Krist, Bijan Nemati, A. J. Riggs, Sam Miller, Laurent Pueyo, Jeremy Kasdin, Kerri Cahoy

Proceedings Volume 11823, 118230Z (2021) https://doi.org/10.1117/12.2594679

KEYWORDS: Wavefronts, Planets, Numerical simulations, Telescopes, Actuators, Wavefront sensors, Thermography, Stars, Space telescopes, Sensors

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Proceedings Article | 12 January 2021 Presentation + Paper

Presentation + Paper

Roman space telescope coronagraph: engineering design and operating concept

Ilya Poberezhskiy, Thomas Luchik, Feng Zhao, Margaret Frerking, Scott Basinger, Eric Cady, M. Mark Colavita, Brandon Creager, Nanaz Fathpour, Renaud Goullioud, Tyler Groff, Patrick Morrissey, Joshua Kempenaar, Brian Kern, Timothy Koch, John Krist, Fai Mok, David Muliere, Bijan Nemati, A.J. Riggs, Byoung-Joon Seo, Fang Shi, Belinda Shreckengost, John Steeves, Hong Tang

Proceedings Volume 11443, 114431V (2021) https://doi.org/10.1117/12.2563480

KEYWORDS: Infrared telescopes, James Webb Space Telescope, Telescopes, Coronagraphy, Infrared radiation, Instrumentation engineering, Optical instrument design, Wavefronts, Imaging spectroscopy, Infrared imaging

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Proceedings Article | 16 December 2020 Poster + Paper

Poster + Paper

A review of simulation and performance modeling tools for the Roman coronagraph instrument

Ewan Douglas, Jaren Ashcraft, Ruslan Belikov, John Debes, Jeremy Kasdin, John Krist, Brianna Lacy, Bijan Nemati, Kian Milani, Leonid Pogorelyuk, A.J. Eldorado Riggs, Dmitry Savransky, Dan Sirbu

Proceedings Volume 11443, 1144338 (2020) https://doi.org/10.1117/12.2561960

KEYWORDS: Device simulation, Coronagraphy, Performance modeling, Exoplanets, Aerospace engineering, Diffraction, Instrument modeling, Speckle, Signal to noise ratio

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Proceedings Article | 15 December 2020 Presentation + Paper

Presentation + Paper

The Nancy Grace Roman Space Telescope Coronagraph Instrument (CGI) technology demonstration

N. Jeremy Kasdin, Vanessa Bailey, Bertrand Mennesson, Robert Zellem, Marie Ygouf, Jason Rhodes, Thomas Luchik, Feng Zhao, A. J. Eldorado Riggs, Byoung-Joon Seo, John Krist, Brian Kern, Hong Tang, Bijan Nemati, Tyler Groff, Neil Zimmerman, Bruce Macintosh, Margaret Turnbull, John Debes, Ewan Douglas, Roxana Lupu

Proceedings Volume 11443, 114431U (2020) https://doi.org/10.1117/12.2562997

KEYWORDS: Coronagraphy, Imaging spectroscopy, Planets, Infrared telescopes, James Webb Space Telescope, Imaging systems, Wavefronts, Algorithm development, Jupiter, Infrared radiation

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Proceedings Article | 13 December 2020 Poster + Paper

Poster + Paper

Prediction and evaluation of the image of the WFIRST coronagraph pupil at the shaped-pupil mask

David Marx, Brian Kern, John Krist, Bala Balasubramanian, A. J. Eldorado Riggs, Byoung-Joon Seo, Eric Cady, Hong Tang, Camilo Prada, Garreth Ruane, Fang Shi, Charley Noecker, Blake Crowther

Proceedings Volume 11443, 1144339 (2020) https://doi.org/10.1117/12.2562629

KEYWORDS: Coronagraphy, Image analysis, Telescopes, Optical instrument design, Optimization (mathematics), Wavefronts, Deformable mirrors, Modulation, Tolerancing, Performance modeling

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Proceedings Article | 13 December 2020 Presentation + Paper

Presentation + Paper

Roman CGI testbed HOWFSC modeling and validation

Hanying Zhou, John Krist, Byoung-Joon Seo, Brian Kern, Eric Cady, Ilya Poberezhskiy

Proceedings Volume 11443, 114431W (2020) https://doi.org/10.1117/12.2561087

KEYWORDS: Coronagraphy, Wavefronts, Diffraction, Instrument modeling, Observatories, Performance modeling, Deformable mirrors

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Proceedings Article | 16 September 2019 Presentation + Paper

Presentation + Paper

The WFIRST coronagraph instrument phase B optical design

Hong Tang, Michael Rodgers, Brandon Creager, John Krist, James McGuire, Keith Patterson, Mayer Rud, Fang Shi, Feng Zhao

Proceedings Volume 11117, 111170C (2019) https://doi.org/10.1117/12.2530506

KEYWORDS: Coronagraphy, Optical design, Mirrors, Deformable mirrors, Exoplanets, Stars, Astronomical imaging, Optical fabrication, Optical alignment, Polarization

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Proceedings Article | 9 September 2019 Presentation + Paper

Presentation + Paper

WFIRST Phase B HLC occulter mask baselining and testbed WFC performance validation

Hanying Zhou, John Krist, Brian Kern, Byoung-Joon Seo, Eric Cady, Bijan Nemati, Dwight Moody, A.J. Eldorado Riggs, David Marx, Daniel Wilson, Kunjithapatham Balasubramanian, Ilya Poberezhskiy, Scott Basinger

Proceedings Volume 11117, 111170H (2019) https://doi.org/10.1117/12.2530672

KEYWORDS: Wavefronts, Tolerancing, Coronagraphy, Telescopes, Performance modeling, Control systems, Mask making, Optical instrument design, Aerospace engineering, Space operations

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Proceedings Article | 9 September 2019 Paper

Paper

Habitable Exoplanet Observatory (HabEx) telescope and optical instruments

Stefan Martin, Gary Kuan, Daniel Stern, Paul Scowen, John Krist, Dimitri Mawet, Garreth Ruane

Proceedings Volume 11117, 1111704 (2019) https://doi.org/10.1117/12.2530737

KEYWORDS: Exoplanets, Telescopes, Observatories, Optical components, Ultraviolet radiation, Coronagraphy, Spectroscopes, Space telescopes, Infrared telescopes, Astrophysics

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Proceedings Article | 9 September 2019 Presentation + Paper

Presentation + Paper

The LUVOIR Extreme Coronagraph for Living Planetary Systems (ECLIPS) II. Performance evaluation, aberration sensitivity analysis and exoplanet detection simulations

Roser Juanola-Parramon, Neil Zimmerman, Laurent Pueyo, Matthew Bolcar, Garreth Ruane, John Krist, Tyler Groff

Proceedings Volume 11117, 1111702 (2019) https://doi.org/10.1117/12.2530356

KEYWORDS: Coronagraphy, Exoplanetary science, Telescopes, Wavefronts, Planets, Stars, Planetary systems, Wavefront sensors, Space operations, Exoplanets

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Proceedings Article | 9 September 2019 Open Access

Open Access

Paper

Numerical modeling of the Habex coronagraph

John Krist, Stefan Martin, Gary Kuan, Bertrand Mennesson, Garreth Ruane, Navtej Saini, John Trauger, James Breckinridge, Dimitri Mawet, Philip Stahl, Jeffrey Davis

Proceedings Volume 11117, 1111705 (2019) https://doi.org/10.1117/12.2530462

KEYWORDS: Coronagraphy, Polarization, Telescopes, Numerical modeling

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SPIE Journal Paper | 20 May 2019

ExoEarth yield landscape for future direct imaging space telescopes

Christopher Stark, Rus Belikov, Matthew Bolcar, Eric Cady, Brendan Crill, Steve Ertel, Tyler Groff, Sergi Hildebrandt, John Krist, P. Douglas Lisman, Johan Mazoyer, Bertrand Mennesson, Bijan Nemati, Laurent Pueyo, Bernard Rauscher, A. J. Riggs, Garreth Ruane, Stuart Shaklan, Dan Sirbu, Rémi Soummer, Kathryn St. Laurent, Neil Zimmerman

JATIS, Vol. 5, Issue 02, 024009, (May 2019) https://doi.org/10.1117/12.10.1117/1.JATIS.5.2.024009

KEYWORDS: Coronagraphy, Stars, Telescopes, Planets, Space telescopes, Optical instrument design, Point spread functions, Mirrors, Exoplanets, Sensors

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Proceedings Article | 9 August 2018 Paper

Paper

Lessons for WFIRST CGI from ground-based high-contrast systems

Vanessa Bailey, Michael Bottom, Eric Cady, Faustine Cantalloube, Jozua de Boer, Tyler Groff, John Krist, Maxwell Millar-Blanchaer, Arthur Vigan, Jeffrey Chilcote, Elodie Choquet, Robert De Rosa, Julien Girard, Olivier Guyon, Brian Kern, Anne-Marie Lagrange, Bruce Macintosh, Jared Males, Christian Marois, Tiffany Meshkat, Julien Milli, Mamadoue N'Diaye, Henry Ngo, Eric Nielsen, Jason Rhodes, Garreth Ruane, Rob van Holstein, Jason Wang, Wenhao Xuan

Proceedings Volume 10698, 106986P (2018) https://doi.org/10.1117/12.2313820

KEYWORDS: Calibration, Stars, Point spread functions, Polarization, Coronagraphy, Satellites, Telescopes, Planets, Polarimetry, Imaging spectroscopy

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Proceedings Article | 1 August 2018 Presentation + Paper

Presentation + Paper

The WFIRST coronagraph instrument: a major step in the exploration of sun-like planetary systems via direct imaging

Bertrand Mennesson, J. Debes, E. Douglas, B. Nemati, C. Stark, J. Kasdin, B. Macintosh, M. Turnbull, M. Rizzo, A. Roberge, N. Zimmerman, K. Cahoy, J. Krist, V. Bailey, J. Trauger, J. Rhodes, L. Moustakas, M. Frerking, F. Zhao, I. Poberezhskiy, R. Demers

Proceedings Volume 10698, 106982I (2018) https://doi.org/10.1117/12.2313861

KEYWORDS: Stars, Coronagraphy, Planets, Imaging systems, Solar system, Clouds, Spatial resolution, Mid-IR, Visible radiation, Exoplanets

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Proceedings Article | 1 August 2018 Paper

Paper

WFIRST CGI integral field spectrograph performance and post-processing in the OS6 observing scenario

Maxime Rizzo, Neil Zimmerman, Tyler Groff, John Krist, A.J. Eldorado Riggs, Qian Gong, Avi Mandell, Prabal Saxena, Michael McElwain, Aki Roberge

Proceedings Volume 10698, 106986U (2018) https://doi.org/10.1117/12.2312400

KEYWORDS: Sensors, Signal to noise ratio, Coronagraphy, Planets, Stars, Spectrographs, Calibration, Data modeling, Point spread functions

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Proceedings Article | 16 July 2018 Presentation + Paper

Presentation + Paper

High accuracy coronagraph flight WFC model for WFIRST-CGI raw contrast sensitivity analysis

Hanying Zhou, John Krist, Eric Cady, Ilya Poberezhskiy

Proceedings Volume 10698, 106982M (2018) https://doi.org/10.1117/12.2313719

KEYWORDS: Telescopes, Error analysis, Polarization, Spectroscopy, Wavefronts, Coronagraphy, Contrast sensitivity, Mirrors, Beam shaping, Exoplanets

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Proceedings Article | 16 July 2018 Presentation + Paper

Presentation + Paper

WFIRST coronagraph flight performance modeling

John Krist, Robert Effinger, Brian Kern, Milan Mandic, James McGuire, Dwight Moody, Patrick Morrissey, Ilya Poberezhskiy, A. J. Riggs, Navtej Saini, Erkin Sidick, Hong Tang, John Trauger

Proceedings Volume 10698, 106982K (2018) https://doi.org/10.1117/12.2310043

KEYWORDS: Coronagraphy, Thermal modeling

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Proceedings Article | 16 July 2018 Paper

Paper

WFIRST coronagraph: digging dark-holes with partially corrected pupil phase

Erkin Sidick, John Krist, Ilya Poberezhskiy

Proceedings Volume 10698, 106986W (2018) https://doi.org/10.1117/12.2313520

KEYWORDS: Coronagraphy, Actuators, Exoplanets, Deformable mirrors, Space telescopes, Stars, Performance modeling, Wavefronts

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Proceedings Article | 6 July 2018 Paper

Paper

Fast linearized coronagraph optimizer (FALCO) II: optical model validation and time savings over other methods

Erkin Sidick, A. J. Eldorado Riggs, Garreth Ruane, John Krist, Dwight Moody, Carl Coker

Proceedings Volume 10698, 106984S (2018) https://doi.org/10.1117/12.2312950

KEYWORDS: Coronagraphy, Actuators, Telescopes, Infrared telescopes, Wavefronts, Control systems, Wavefront sensors, Deformable mirrors, Space telescopes, Device simulation

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Proceedings Article | 5 September 2017 Paper

Paper

HabEx space telescope optical system

Stefan Martin, Mayer Rud, Paul Scowen, Daniel Stern, Joel Nissen, John Krist

Proceedings Volume 10398, 1039805 (2017) https://doi.org/10.1117/12.2275191

KEYWORDS: Space telescopes, Exoplanets, Spectrographs, Telescopes, Stars, Optical instrument design, Cameras, Imaging systems, Spectrometers, Near infrared

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Proceedings Article | 1 September 2017 Presentation + Paper

Presentation + Paper

Sensitivity of the WFIRST coronagraph performance to key instrument parameters

Bijan Nemati, John Krist, Bertrand Mennesson

Proceedings Volume 10400, 1040007 (2017) https://doi.org/10.1117/12.2274396

KEYWORDS: Signal to noise ratio, Stars, Coronagraphy, Planets, Speckle, Spectroscopy, Sensors, Point spread functions, Imaging spectroscopy

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Proceedings Article | 1 September 2017 Presentation + Paper

Presentation + Paper

Simulating the WFIRST coronagraph integral field spectrograph

Maxime Rizzo, Tyler Groff, Neil Zimmermann, Qian Gong, Avi Mandell, Prabal Saxena, Michael McElwain, Aki Roberge, John Krist, A. J. Eldorado Riggs, Eric Cady, Camilo Mejia Prada, Timothy Brandt, Ewan Douglas, Kerri Cahoy

Proceedings Volume 10400, 104000B (2017) https://doi.org/10.1117/12.2273066

KEYWORDS: Iterated function systems, Spectrographs, Device simulation, Exoplanets, Atmospheric sciences, Planets, Stars, Cameras, Speckle, Wavefronts

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Proceedings Article | 1 September 2017 Presentation + Paper

Presentation + Paper

The WFIRST coronagraph instrument optical design update

Hong Tang, Richard Demers, John Krist, James McGuire, Mayer Rud, Feng Zhao

Proceedings Volume 10400, 1040003 (2017) https://doi.org/10.1117/12.2274549

KEYWORDS: Optical design, Wavefronts, Exoplanets, Coronagraphy, Stars, Channel projecting optics, Iterated function systems, Polarization, Optical coatings, Stray light analysis

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Proceedings Article | 1 September 2017 Presentation + Paper

Presentation + Paper

WFIRST coronagraph optical modeling

John Krist, A. J. Riggs, James McGuire, Hong Tang, Nikta Amiri, Gary Gutt, Luis Marchen, David Marx, Bijan Nemati, Navtej Saini, Erkin Sidick, Hanying Zhou

Proceedings Volume 10400, 1040004 (2017) https://doi.org/10.1117/12.2274792

KEYWORDS: Performance modeling, Systems modeling, Exoplanets, Spectrographs, Mirrors, Telescopes, Wavefront sensors, Polarization, Tolerancing, MATLAB

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Proceedings Article | 1 September 2017 Paper

Paper

Shaped pupil coronagraph design improvements for the WFIRST coronagraph instrument

A. J. Eldorado Riggs, Neil Zimmerman, Bijan Nemati, John Krist

Proceedings Volume 10400, 104000O (2017) https://doi.org/10.1117/12.2274437

KEYWORDS: Exoplanets, Planets, Diffraction, Monochromatic aberrations, Tolerancing, Interferometry

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Proceedings Article | 1 September 2017 Presentation + Paper

Presentation + Paper

Wavefront control performance modeling with WFIRST shaped pupil coronagraph testbed

Hanying Zhou, Bijian Nemati, John Krist, Eric Cady, Brian Kern, Ilya Poberezhskiy

Proceedings Volume 10400, 1040005 (2017) https://doi.org/10.1117/12.2274391

KEYWORDS: Performance modeling, Wavefronts, Wavefront sensors, Control systems, Systems modeling, Exoplanets, Monte Carlo methods, Imaging systems, Space telescopes, Stars

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Proceedings Article | 9 August 2016 Paper

Paper

Diffraction modeling of finite subband EFC probing on dark hole contrast with WFIRST-CGI shaped pupil coronagraph

Hanying Zhou, John Krist, Bijan Nemati

Proceedings Volume 9911, 99111S (2016) https://doi.org/10.1117/12.2232129

KEYWORDS: Diffraction, Bandpass filters, Wavefront sensors, Optical filters, Coronagraphy, Error analysis, Wavefronts, Infrared telescopes, Stars, Telescopes

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Proceedings Article | 29 July 2016 Paper

Paper

Closing the contrast gap between testbed and model prediction with WFIRST-CGI shaped pupil coronagraph

Hanying Zhou, Bijan Nemati, John Krist, Eric Cady, Camilo Prada, Brian Kern, Ilya Poberezhskiy

Proceedings Volume 9904, 990419 (2016) https://doi.org/10.1117/12.2232211

KEYWORDS: Speckle, Actuators, Error control coding, Coronagraphy, Wavefronts, Error analysis, Control systems, Data modeling, Monochromatic aberrations, Phase measurement

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Proceedings Article | 29 July 2016 Paper

Paper

Data processing and algorithm development for the WFIRST coronagraph: comparison of RDI and ADI strategies and impact of spatial sampling on post-processing

Marie Ygouf, Neil Zimmerman, Laurent Pueyo, Rémi Soummer, Marshall Perrin, Bertrand Mennesson, John Krist, Gautam Vasisht, Bijan Nemati, Bruce Macintosh

Proceedings Volume 9904, 99045M (2016) https://doi.org/10.1117/12.2231581

KEYWORDS: Exoplanets, Point spread functions, Space telescopes, Telescopes, Point spread functions, Stars, Algorithm development, Coronagraphy, Speckle, Planets, Iterated function systems

Read Abstract +

Direct detection and characterization of mature giant or sub-Neptune exoplanets in the visible will require space- based instruments optimized for high-contrast imaging with contrasts of 10^-9. In this context, the coronagraph instrument (CGI) on the Wide-Field Infrared Survey Telescope (WFIRST) will reach raw contrasts of about 10^-8 or better using state-of-the-art starlight suppression and wavefront control techniques. A ten-fold contrast improvement is therefore required using post-processing techniques in order to detect 10^-9 planets from speckles. Post-processing techniques that are successful on both ground-based and space-based instruments need to be validated at such high contrast levels. In this communication, we investigate speckle subtraction techniques for different observation strategies and hardware parameters on WFIRST-like simulated images in the presence of deformable mirrors and an hybrid lyot coronagraph (HLC). We compare the contrast gain after post-processing in both speckle-noise and photon-noise dominated regimes for two different observing scenarios: the reference star differential imaging (RDI) and the angular differential imaging (ADI). We find that the ADI observing strategy is more robust to speckle and photon noises than the RDI observing strategy, enabling up to a threefold gain with respect to the latter. Thus, we recommend that the telescope be able to roll by at least 13° off nominal. We investigated the impact of spatial sampling on post-processed sensitivity, in the context of design trade studies for the Integral Field Spectrograph (IFS) component of the instrument. Our preliminary results suggest that the spatial sampling can be halved from the baseline sampling rate (~4 lenslets per λ/D) without any degradation in final contrast, thereby reducing the integration time required for spectroscopic characterization. In the speckle-noise dominated regime, we also find that at Nyquist sampling or higher, sub-pixel reference- to-target offsets have a negligible impact on the level of residual speckles after post-processing.

SPIE Journal Paper | 28 January 2016

Phase-induced amplitude apodization complex mask coronagraph mask fabrication, characterization, and modeling for WFIRST-AFTA

Brian Kern, Olivier Guyon, Ruslan Belikov, Daniel Wilson, Richard Muller, Erkin Sidick, Bala Balasubramanian, John Krist, Ilya Poberezhskiy, Hong Tang

JATIS, Vol. 2, Issue 01, 011014, (January 2016) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011014

KEYWORDS: Planets, Coronagraphy, Wavefronts, Apodization, Scanning electron microscopy, Mask making, Atomic force microscopy, Reflectivity, Mirrors, Polymethylmethacrylate

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SPIE Journal Paper | 14 January 2016 Open Access

Open Access

Hybrid Lyot coronagraph for WFIRST-AFTA: coronagraph design and performance metrics

John Trauger, Dwight Moody, John Krist, Brian Gordon

JATIS, Vol. 2, Issue 01, 011013, (January 2016) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011013

KEYWORDS: Coronagraphy, Telescopes, Wavefronts, Exoplanets, Stars, Space telescopes, Optical instrument design, Mirrors, Imaging spectroscopy, Dielectrics

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SPIE Journal Paper | 7 December 2015

WFIRST-AFTA coronagraph shaped pupil masks: design, fabrication, and characterization

Kunjithapatham Balasubramanian, Victor White, Karl Yee, Pierre Echternach, Richard Muller, Matthew Dickie, Eric Cady, Camilo Prada, Daniel Ryan, Ilya Poberezhskiy, Brian Kern, Hanying Zhou, John Krist, Bijan Nemati, A. J. Eldorado Riggs, Neil Zimmerman, N. Jeremy Kasdin

JATIS, Vol. 2, Issue 01, 011005, (December 2015) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011005

KEYWORDS: Photomasks, Silicon, Coronagraphy, Reflectivity, Semiconducting wafers, Aluminum, Point spread functions, Wavefronts, Optical instrument design, Etching

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SPIE Journal Paper | 28 October 2015

Numerical modeling of the proposed WFIRST-AFTA coronagraphs and their predicted performances

John Krist, Bijan Nemati, Bertrand Mennesson

JATIS, Vol. 2, Issue 01, 011003, (October 2015) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011003

KEYWORDS: Coronagraphy, Wavefronts, Stars, Polarization, Point spread functions, Planets, Numerical modeling, Telescopes, Speckle, Monochromatic aberrations

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Proceedings Article | 16 September 2015 Paper

Paper

The WFIRST/AFTA coronagraph instrument optical design

Hong Tang, Mayer Rud, Richard Demers, Renaud Goullioud, John Krist, Fang Shi, Feng Zhao

Proceedings Volume 9605, 960504 (2015) https://doi.org/10.1117/12.2188446

KEYWORDS: Coronagraphy, Telescopes, Iterated function systems, Mirrors, Infrared telescopes, Polarization, Optical design, Collimators, Cameras, Stars

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Proceedings Article | 16 September 2015 Paper

Paper

Low order wavefront sensing and control for WFIRST-AFTA coronagraph

Fang Shi, Kunjithapatham Balasubramanian, Randall Bartos, Randall Hein, Brian Kern, John Krist, Raymond Lam, Douglas Moore, James Moore, Keith Patterson, Ilya Poberezhskiy, Joel Shields, Erkin Sidick, Hong Tang, Tuan Truong, Kent Wallace, Xu Wang, Dan Wilson

Proceedings Volume 9605, 960509 (2015) https://doi.org/10.1117/12.2188775

KEYWORDS: Coronagraphy, Wavefronts, Wavefront sensors, Actuators, Telescopes, Calibration, Sensors, Mirrors, Monochromatic aberrations, Space telescopes

Read Abstract +

Proceedings Article | 16 September 2015 Paper

Paper

PIAA coronagraph design for the Exo-C Mission concept

Ruslan Belikov, John Krist, Karl Stapelfeldt

Proceedings Volume 9605, 96050V (2015) https://doi.org/10.1117/12.2188934

KEYWORDS: Apodization, Coronagraphy, Mirrors, Stars, Wavefronts, Space telescopes, Point spread functions, Telescopes, Polarization, Exoplanets

Read Abstract +

Proceedings Article | 16 September 2015 Paper

Paper

Hybrid Lyot coronagraph for WFIRST-AFTA: coronagraph design and performance metrics

John Trauger, Brian Gordon, John Krist, Dwight Moody

Proceedings Volume 9605, 96050N (2015) https://doi.org/10.1117/12.2190625

KEYWORDS: Coronagraphy, Telescopes, Wavefronts, Exoplanets, Space telescopes, Stars, Mirrors, Optical instrument design, Actuators, Deformable mirrors

Read Abstract +

Proceedings Article | 16 September 2015 Paper

Paper

Exo-C: a probe-scale space observatory for direct imaging and spectroscopy of extrasolar planetary systems

Karl Stapelfeldt, Frank Dekens, Michael Brenner, Keith Warfield, Ruslan Belikov, Paul Brugarolas, Geoffrey Bryden, Kerri Cahoy, Supriya Chakrabarti, Serge Dubovitsky, Robert Effinger, Brian Hirsch, Andrew Kissil, John Krist, Jared Lang, Mark Marley, Michael McElwain, Victoria Meadows, Joel Nissen, Jeffrey Oseas, Chris Pong, Eugene Serabyn, Eric Sunada, John Trauger, Stephen Unwin

Proceedings Volume 9605, 96050T (2015) https://doi.org/10.1117/12.2191720

KEYWORDS: Planets, Coronagraphy, Telescopes, Space telescopes, Stars, Exoplanets, Wavefronts, Space operations, Imaging spectroscopy, Spectroscopy

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Proceedings Article | 16 September 2015 Paper

Paper

WFIRST-AFTA coronagraph performance: feedback from post-processing studies to overall design

Bertrand Mennesson, John Krist, Bijan Nemati, Marie Ygouf, Laurent Pueyo, Remi Soummer, Marshall Perrin

Proceedings Volume 9605, 96050D (2015) https://doi.org/10.1117/12.2189403

KEYWORDS: Coronagraphy, Stars, Planets, Point spread functions, Calibration, Wavefronts, Exoplanets, Speckle, Polarization, Image processing

Read Abstract +

Proceedings Article | 4 September 2015 Paper

Paper

An overview of WFIRST/AFTA coronagraph optical modeling

John Krist, Bijan Nemati, Hanying Zhou, Erkin Sidick

Proceedings Volume 9605, 960505 (2015) https://doi.org/10.1117/12.2188361

KEYWORDS: Coronagraphy, Wavefronts, Polarization, Point spread functions, Stars, Telescopes, Space telescopes, Monochromatic aberrations, Planets, Mirrors

Read Abstract +

Proceedings Article | 28 August 2014 Paper

Paper

Exo-C: a probe-scale space mission to directly image and spectroscopically characterize exoplanetary systems using an internal coronagraph

Karl Stapelfeldt, Michael Brenner, Keith Warfield, Frank Dekens, Ruslan Belikov, Paul Brugarolas, Geoffrey Bryden, Kerri Cahoy, Supriya Chakrabarti, Serge Dubovitsky, Robert Effinger, Brian Hirsch, Andrew Kissil, John Krist, Jared Lang, Mark Marley, Michael McElwain, Victoria Meadows, Joel Nissen, Jeffrey Oseas, Eugene Serabyn, Eric Sunada, John Trauger, Stephen Unwin

Proceedings Volume 9143, 91432K (2014) https://doi.org/10.1117/12.2057115

KEYWORDS: Planets, Coronagraphy, Stars, Space telescopes, Telescopes, Space operations, Exoplanets, Wavefronts, Mirrors, Iterated function systems

Read Abstract +

Proceedings Article | 2 August 2014 Paper

Paper

Science yield estimation for AFTA coronagraphs

Wesley Traub, Ruslan Belikov, Olivier Guyon, N. Jeremy Kasdin, John Krist, Bruce Macintosh, Bertrand Mennesson, Dmitry Savransky, Michael Shao, Eugene Serabyn, John Trauger

Proceedings Volume 9143, 91430N (2014) https://doi.org/10.1117/12.2054834

KEYWORDS: Planets, Coronagraphy, Speckle, Stars, Exoplanets, Space telescopes, Infrared telescopes, Signal to noise ratio, Jupiter, Sensors

Read Abstract +

Proceedings Article | 2 August 2014 Paper

Paper

End-to-end numerical modeling of AFTA coronagraphs

John Krist

Proceedings Volume 9143, 91430V (2014) https://doi.org/10.1117/12.2056759

KEYWORDS: Coronagraphy, Wavefronts, Point spread functions, Planets, Space telescopes, Telescopes, Control systems, Stars, Wave propagation, Adaptive optics

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Proceedings Article | 2 August 2014 Paper

Paper

Technology development towards WFIRST-AFTA coronagraph

Ilya Poberezhskiy, Feng Zhao, Xin An, Kunjithapatham Balasubramanian, Ruslan Belikov, Eric Cady, Richard Demers, Rosemary Diaz, Qian Gong, Brian Gordon, Renaud Goullioud, Frank Greer, Olivier Guyon, Michael Hoenk, N. Jeremy Kasdin, Brian Kern, John Krist, Andreas Kuhnert, Michael McElwain, Bertrand Mennesson, Dwight Moody, Richard Muller, Bijan Nemati, Keith Patterson, A. J. Riggs, Daniel Ryan, Byoung-Joon Seo, Stuart Shaklan, Erkin Sidick, Fang Shi, Nicholas Siegler, Rémi Soummer, Hong Tang, John Trauger, J. Kent Wallace, Xu Wang, Victor White, Daniel Wilson, Karl Yee, Hanying Zhou, Neil Zimmerman

Proceedings Volume 9143, 91430P (2014) https://doi.org/10.1117/12.2060320

KEYWORDS: Coronagraphy, Sensors, Wavefronts, Wavefront sensors, Iterated function systems, Photomasks, Space telescopes, Exoplanets, Deformable mirrors, Planets

Read Abstract +

Proceedings Article | 26 September 2013 Paper

Paper

High-contrast imaging results with the vortex coronagraph

E. Serabyn, J. Trauger, D. Moody, D. Mawet, K. Liewer, J. Krist, B. Kern

Proceedings Volume 8864, 88640Y (2013) https://doi.org/10.1117/12.2024660

KEYWORDS: Coronagraphy, Light, Polarization, Wave plates, Stars, Space telescopes, Cameras, Polarizers, Point spread functions, Speckle

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Proceedings Article | 26 September 2013 Paper

Paper

The Debris Disk Explorer: a balloon-borne coronagraph for observing debris disks

Lewis Roberts, Geoffrey Bryden, Wesley Traub, Stephen Unwin, John Trauger, John Krist, Jack Aldrich, Paul Brugarolas, Karl Stapelfeldt, Mark Wyatt, David Stuchlik, James Lanzi

Proceedings Volume 8864, 88640A (2013) https://doi.org/10.1117/12.2025282

KEYWORDS: Stars, Coronagraphy, Telescopes, Planets, Mirrors, Wavefront sensors, Planetary systems, Solar system, Space telescopes, Light scattering

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Proceedings Article | 26 September 2013 Paper

Paper

Assessing the performance limits of internal coronagraphs through end-to-end modeling

John Krist, Ruslan Belikov, Laurent Pueyo, Dimitri Mawet, Dwight Moody, John Trauger, Stuart Shaklan

Proceedings Volume 8864, 88640P (2013) https://doi.org/10.1117/12.2024954

KEYWORDS: Coronagraphy, Wavefronts, Wave propagation, Deformable mirrors, Polarization, Control systems, Diffraction, Mirrors, Coating, Stars

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Proceedings Article | 26 September 2013 Paper

Paper

HCIT contrast performance sensitivity studies: simulation versus experiment

Erkin Sidick, Stuart Shaklan, John Krist, Eric Cady, Brian Kern, Kunjithapatham Balasubramanian

Proceedings Volume 8864, 88640Q (2013) https://doi.org/10.1117/12.2024516

KEYWORDS: Coronagraphy, Opacity, Actuators, Systems modeling, Wavefronts, Cesium, 3D modeling, Exoplanets, Optical simulations, Device simulation

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Proceedings Article | 21 September 2012 Paper

Paper

Coronagraphic imaging of debris disks from a high altitude balloon platform

Stephen Unwin, Wesley Traub, Geoffrey Bryden, Paul Brugarolas, Pin Chen, Olivier Guyon, Lynn Hillenbrand, John Krist, Bruce Macintosh, Dimitri Mawet, Bertrand Mennesson, Dwight Moody, Lewis Roberts, Karl Stapelfeldt, David Stuchlik, John Trauger, Gautam Vasisht

Proceedings Volume 8442, 84420G (2012) https://doi.org/10.1117/12.924175

KEYWORDS: Coronagraphy, Telescopes, Stars, Planets, Space telescopes, Wavefronts, Sensors, Wavefront sensors, Planetary systems, Solar system

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Proceedings Article | 21 September 2012 Paper

Paper

Science opportunities with the near-IR camera (NIRCam) on the James Webb Space Telescope (JWST)

Charles Beichman, Marcia Rieke, Daniel Eisenstein, Thomas Greene, John Krist, Don McCarthy, Michael Meyer, John Stansberry

Proceedings Volume 8442, 84422N (2012) https://doi.org/10.1117/12.925447

KEYWORDS: James Webb Space Telescope, Stars, Planets, Galactic astronomy, Space telescopes, Telescopes, Sensors, Wavefronts, Cameras, Coronagraphy

Read Abstract +

Proceedings Article | 21 September 2012 Paper

Paper

End-to-end coronagraphic modeling including a low-order wavefront sensor

John Krist, John Trauger, Stephen Unwin, Wesley Traub

Proceedings Volume 8442, 844253 (2012) https://doi.org/10.1117/12.927143

KEYWORDS: Wavefronts, Coronagraphy, Telescopes, Wavefront sensors, Space telescopes, Stars, Planets, Mirrors, Phase contrast, Actuators

Read Abstract +

Proceedings Article | 21 September 2012 Paper

Paper

Review of small-angle coronagraphic techniques in the wake of ground-based second-generation adaptive optics systems

Dimitri Mawet, Laurent Pueyo, Peter Lawson, Laurent Mugnier, Wesley Traub, Anthony Boccaletti, John Trauger, Szymon Gladysz, Eugene Serabyn, Julien Milli, Ruslan Belikov, Markus Kasper, Pierre Baudoz, Bruce Macintosh, Christian Marois, Ben Oppenheimer, Harrisson Barrett, Jean-Luc Beuzit, Nicolas Devaney, Julien Girard, Olivier Guyon, John Krist, Bertrand Mennesson, David Mouillet, Naoshi Murakami, Lisa Poyneer, Dmitri Savransky, Christophe Vérinaud, James Wallace

Proceedings Volume 8442, 844204 (2012) https://doi.org/10.1117/12.927245

KEYWORDS: Coronagraphy, Space telescopes, Telescopes, Adaptive optics, Stars, Spiral phase plates, Planets, Wavefronts, Cameras, Modulation

Read Abstract +

Proceedings Article | 21 September 2012 Paper

Paper

Complex apodization Lyot coronagraphy for the direct imaging of exoplanet systems: design, fabrication, and laboratory demonstration

John Trauger, Dwight Moody, Brian Gordon, John Krist, Dimitri Mawet

Proceedings Volume 8442, 84424Q (2012) https://doi.org/10.1117/12.926663

KEYWORDS: Coronagraphy, Stars, Optical filters, Dielectrics, Calibration, Exoplanets, Deformable mirrors, Imaging systems, Metals, Imaging spectroscopy

Read Abstract +

Proceedings Article | 13 September 2012 Paper

Paper

On advanced estimation techniques for exoplanet detection and characterization using ground-based coronagraphs

Peter Lawson, Lisa Poyneer, Harrison Barrett, Richard Frazin, Luca Caucci, Nicholas Devaney, Lars Furenlid, Szymon Gładysz, Olivier Guyon, John Krist, Jérôme Maire, Christian Marois, Dimitri Mawet, David Mouillet, Laurent Mugnier, Iain Pearson, Marshall Perrin, Laurent Pueyo, Dmitry Savransky

Proceedings Volume 8447, 844722 (2012) https://doi.org/10.1117/12.925099

KEYWORDS: Planets, Stars, Gemini Planet Imager, Exoplanets, Adaptive optics, Coronagraphy, Speckle, Point spread functions, Astronomy, Computer simulations

Read Abstract +

Proceedings Article | 12 September 2012 Paper

Paper

Aperture mask interferometry with an integral field spectrograph

Neil Zimmerman, Anand Sivaramakrishnan, David Bernat, Ben Oppenheimer, Sasha Hinkley, James Lloyd, Peter Tuthill, Douglas Brenner, Ian Parry, Michal Simon, John Krist, Laurent Pueyo

Proceedings Volume 8445, 84452G (2012) https://doi.org/10.1117/12.926204

KEYWORDS: Stars, Adaptive optics, Calibration, Iterated function systems, Telescopes, Spectrographs, Interferometry, Space telescopes, Coronagraphy, Spectroscopy

Read Abstract +

Proceedings Article | 29 September 2011 Paper

Paper

NIRCam coronagraphic Lyot stop: design, fabrication, and testing

Yalan Mao, Torben Andersen, Tracy Kubo, Miguel Virgen, Henry Chan, Greg Feller, Lynn Huff, Eric Smith, Gopal Vasudevan, Steve Somerstein, Tom Jamieson, Scott Horner, John Krist, Charles Beichman, Carmen Barone, Ron Schmidt, Donna Levin, Steve Seymour, Douglas Kelly, Marcia Rieke

Proceedings Volume 8150, 81500E (2011) https://doi.org/10.1117/12.896451

KEYWORDS: Coronagraphy, Point spread functions, James Webb Space Telescope, Absorbance, Optical filters, Image filtering, Ferroelectric LCDs, Staring arrays, Coating, Silicon

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Proceedings Article | 22 September 2011 Paper

Paper

20 years of Hubble Space Telescope optical modeling using Tiny Tim

John Krist, Richard Hook, Felix Stoehr

Proceedings Volume 8127, 81270J (2011) https://doi.org/10.1117/12.892762

KEYWORDS: Point spread functions, Cameras, Sensors, Stars, Mirrors, Diffusion, Monochromatic aberrations, Charge-coupled devices, Data modeling, Space telescopes

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Proceedings Article | 15 September 2011 Paper

Paper

Assessing the performance limits of internal coronagraphs through end-to-end modeling: a NASA TDEM study

John Krist, Ruslan Belikov, Laurent Pueyo, Dimitri Mawet, Dwight Moody, John Trauger, Stuart Shaklan

Proceedings Volume 8151, 81510E (2011) https://doi.org/10.1117/12.892772

KEYWORDS: Wavefronts, Wave propagation, Coronagraphy, Actuators, Spatial frequencies, Control systems, Telescopes, Diffraction, Apodization, Mirrors

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Proceedings Article | 15 September 2011 Paper

Paper

Zodiac II: debris disk science from a balloon

Geoffrey Bryden, Wesley Traub, Lewis Roberts, Robin Bruno, Stephen Unwin, Stan Backovsky, Paul Brugarolas, Supriya Chakrabarti, Pin Chen, Lynne Hillenbrand, John Krist, Charles Lillie, Bruce Macintosh, Dimitri Mawet, Bertrand Mennesson, Dwight Moody, Zahidul Rahman, Justin Rey, Karl Stapelfeldt, David Stuchlik, John Trauger, Gautam Vaischt

Proceedings Volume 8151, 81511E (2011) https://doi.org/10.1117/12.899688

KEYWORDS: Telescopes, Stars, Coronagraphy, Space telescopes, Planets, Mirrors, Wavefronts, Signal to noise ratio, Deformable mirrors, Speckle

Read Abstract +

Proceedings Article | 15 September 2011 Paper

Paper

Stability error budget for an aggressive coronagraph on a 3.8 m telescope

Stuart Shaklan, Luis Marchen, John Krist, Mayer Rud

Proceedings Volume 8151, 815109 (2011) https://doi.org/10.1117/12.892838

KEYWORDS: Monochromatic aberrations, Coronagraphy, Mirrors, Phase modulation, Telescopes, Planets, Signal to noise ratio, Control systems, Wavefronts, Diffraction

Read Abstract +

Proceedings Article | 15 September 2011 Paper

Paper

A hybrid Lyot coronagraph for the direct imaging and spectroscopy of exoplanet systems: recent results and prospects

John Trauger, Dwight Moody, Brian Gordon, John Krist, Dimitri Mawet

Proceedings Volume 8151, 81510G (2011) https://doi.org/10.1117/12.895032

KEYWORDS: Coronagraphy, Imaging spectroscopy, Stars, Exoplanets, Imaging systems, Deformable mirrors, Wavefronts, Dielectrics, Signal attenuation, Planets

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Proceedings Article | 15 September 2011 Paper

Paper

Taking the vector vortex coronagraph to the next level for ground- and space-based exoplanet imaging instruments: review of technology developments in the USA, Japan, and Europe

Dimitri Mawet, Naoshi Murakami, Christian Delacroix, Eugene Serabyn, Olivier Absil, Naoshi Baba, Jacques Baudrand, Anthony Boccaletti, Rick Burruss, Russell Chipman, Pontus Forsberg, Serge Habraken, Shoki Hamaguchi, Charles Hanot, Akitoshi Ise, Mikael Karlsson, Brian Kern, John Krist, Andreas Kuhnert, Marie Levine, Kurt Liewer, Stephen McClain, Scott McEldowney, Bertrand Mennesson, Dwight Moody, Hiroshi Murakami, Albert Niessner, Jun Nishikawa, Nada O'Brien, Kazuhiko Oka, Peggy Park, Pierre Piron, Laurent Pueyo, Pierre Riaud, Moritsugu Sakamoto, Motohide Tamura, John Trauger, David Shemo, Jean Surdej, Nelson Tabirian, Wesley Traub, James Wallace, Kaito Yokochi

Proceedings Volume 8151, 815108 (2011) https://doi.org/10.1117/12.896059

KEYWORDS: Coronagraphy, Polarization, Spiral phase plates, Photonic crystals, Liquid crystals, Polymers, Telescopes, Exoplanets, Space telescopes, Optics manufacturing

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Proceedings Article | 11 August 2010 Paper

Paper

The JWST/NIRCam coronagraph flight occulters

John Krist, Kunjithapatham Balasubramanian, Richard Muller, Stuart Shaklan, Douglas Kelly, Daniel Wilson, Charles Beichman, Eugene Serabyn, Yalan Mao, Pierre Echternach, John Trauger, Kurt Liewer

Proceedings Volume 7731, 77313J (2010) https://doi.org/10.1117/12.856488

KEYWORDS: Coronagraphy, James Webb Space Telescope, Coating, Aluminum, Antireflective coatings, Photomasks, Microscopes, Absorbance, Neodymium, Image transmission

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Proceedings Article | 10 August 2010 Paper

Paper

Practical numerical propagation of arbitrary wavefronts through PIAA optics

John Krist, Laurent Pueyo, Stuart Shaklan

Proceedings Volume 7731, 77314N (2010) https://doi.org/10.1117/12.856490

KEYWORDS: Wavefronts, Wave propagation, Coronagraphy, Apodization, Diffraction, Spatial frequencies, Actuators, Stars, Computing systems, Telescopes

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Proceedings Article | 6 August 2010 Paper

Paper

ACCESS: a concept study for the direct imaging and spectroscopy of exoplanetary systems

John Trauger, Karl Stapelfeldt, Wesley Traub, John Krist, Dwight Moody, Dimitri Mawet, Eugene Serabyn, Curtis Henry, Paul Brugarolas, James Alexander, Robert Gappinger, Olivia Dawson, Virgil Mireles, Peggy Park, Laurent Pueyo, Stuart Shaklan, Olivier Guyon, Jeremy Kasdin, Robert Vanderbei, David Spergel, Ruslan Belikov, Geoffrey Marcy, Robert Brown, Jean Schneider, Bruce Woodgate, Robert Egerman, Gary Matthews, Jason Elias, Yves Conturie, Phillip Vallone, Perry Voyer, Ronald Polidan, Charles Lillie, Constance Spittler, David Lee, Reem Hejal, Allen Bronowicki, Nick Saldivar, Mark Ealey, Thomas Price

Proceedings Volume 7731, 773128 (2010) https://doi.org/10.1117/12.858301

KEYWORDS: Coronagraphy, Stars, Planets, Mirrors, Telescopes, Space telescopes, Exoplanets, Imaging systems, Observatories, Imaging spectroscopy

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Proceedings Article | 5 August 2010 Paper

Paper

NIRCam: development and testing of the JWST near-infrared camera

Thomas Greene, Charles Beichman, Michael Gully-Santiago, Daniel Jaffe, Douglas Kelly, John Krist, Marcia Rieke, Eric Smith

Proceedings Volume 7731, 77310C (2010) https://doi.org/10.1117/12.856615

KEYWORDS: James Webb Space Telescope, Sensors, Cameras, Coronagraphy, Fermium, Frequency modulation, Optical fabrication, Cryogenics, Image segmentation, Wavefronts

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Proceedings Article | 20 July 2010 Paper

Paper

The Vector Vortex Coronagraph: sensitivity to central obscuration, low-order aberrations, chromaticism, and polarization

Dimitri Mawet, Laurent Pueyo, Dwight Moody, John Krist, Eugene Serabyn

Proceedings Volume 7739, 773914 (2010) https://doi.org/10.1117/12.858240

KEYWORDS: Polarization, Coronagraphy, Spiral phase plates, Space telescopes, Telescopes, Colorimetry, Wavefront sensors, Exoplanets, Monochromatic aberrations, Optical vortices

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Proceedings Article | 20 August 2009 Paper

Paper

End-to-end simulations of different coronagraphic techniques

John Krist, Dwight Moody, Dimitri Mawet, John Trauger, Ruslan Belikov, Stuart Shaklan, Olivier Guyon, Robert Vanderbei

Proceedings Volume 7440, 744016 (2009) https://doi.org/10.1117/12.826487

KEYWORDS: Wavefronts, Coronagraphy, Wave propagation, Mirrors, Spiral phase plates, Apodization, Actuators, Telescopes, Optical vortices, Exoplanets

Read Abstract +

Proceedings Article | 20 August 2009 Paper

Paper

The JWST/NIRCam coronagraph: mask design and fabrication

John Krist, Kunjithapatham Balasubramanian, Charles Beichman, Pierre Echternach, Joseph Green, Kurt Liewer, Richard Muller, Eugene Serabyn, Stuart Shaklan, John Trauger, Daniel Wilson, Scott Horner, Yalan Mao, Stephen Somerstein, Gopal Vasudevan, Douglas Kelly, Marcia Rieke

Proceedings Volume 7440, 74400W (2009) https://doi.org/10.1117/12.826448

KEYWORDS: Coronagraphy, James Webb Space Telescope, Stars, Halftones, Telescopes, Diffraction, Coating, Photomasks, Sapphire, Light scattering

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Proceedings Article | 20 August 2009 Paper

Paper

Vector vortex coronagraph: first results in the visible

Dimitri Mawet, John Trauger, Eugene Serabyn, Dwight Moody, Kurt Liewer, John Krist, David Shemo, Nada O'Brien

Proceedings Volume 7440, 74400X (2009) https://doi.org/10.1117/12.826569

KEYWORDS: Coronagraphy, Spiral phase plates, Polarization, Wavefronts, Optical vortices, Space telescopes, Exoplanets, Telescopes, Manufacturing, Wavefront sensors

Read Abstract +

Proceedings Article | 20 August 2009 Paper

Paper

Numerical propagator through PIAA optics

Laurent Pueyo, Stuart Shaklan, Amir Give'on, John Krist

Proceedings Volume 7440, 74400E (2009) https://doi.org/10.1117/12.825189

KEYWORDS: Point spread functions, Wave propagation, Coronagraphy, Mirrors, Wavefronts, Apodization, Spatial frequencies, Light wave propagation, Detection and tracking algorithms, Fourier transforms

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Proceedings Article | 14 July 2008 Paper

Paper

ACCESS: a NASA mission concept study of an Actively Corrected Coronagraph for Exoplanet System Studies

John Trauger, Karl Stapelfeldt, Wesley Traub, Curt Henry, John Krist, Dimitri Mawet, Dwight Moody, Peggy Park, Laurent Pueyo, Eugene Serabyn, Stuart Shaklan, Olivier Guyon, Jeremy Kasdin, David Spergel, Robert Vanderbei, Ruslan Belikov, Geoffrey Marcy, Robert Brown, Jean Schneider, Bruce Woodgate, Gary Matthews, Robert Egerman, Ronald Polidan, Charles Lillie, Mark Ealey, Thomas Price

Proceedings Volume 7010, 701029 (2008) https://doi.org/10.1117/12.789119

KEYWORDS: Coronagraphy, Stars, Planets, Telescopes, Space telescopes, Mirrors, Wavefronts, Control systems, Space operations, Imaging systems

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Proceedings Article | 12 July 2008 Paper

Paper

Extraction of extrasolar planet spectra from realistically simulated wavefront-corrected coronagraphic fields

John Krist, Stuart Shaklan, Marie Levine

Proceedings Volume 7010, 701044 (2008) https://doi.org/10.1117/12.789788

KEYWORDS: Planets, Wavefronts, Stars, Telescopes, Coronagraphy, Space telescopes, Deformable mirrors, Device simulation, Optical filters, Actuators

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Proceedings Article | 23 October 2007 Paper

Paper

PROPER: an optical propagation library for IDL

John Krist

Proceedings Volume 6675, 66750P (2007) https://doi.org/10.1117/12.731179

KEYWORDS: Wavefronts, Coronagraphy, Wave propagation, Stars, Planets, Beam propagation method, Diffraction, Radio propagation, Deformable mirrors, Zernike polynomials

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Proceedings Article | 19 September 2007 Paper

Paper

Hunting planets and observing disks with the JWST NIRCam coronagraph

John Krist, Charles Beichman, John Trauger, Marcia Rieke, Steve Somerstein, Joseph Green, Scott Horner, John Stansberry, Fang Shi, Michael Meyer, Karl Stapelfeldt, Thomas Roellig

Proceedings Volume 6693, 66930H (2007) https://doi.org/10.1117/12.734873

KEYWORDS: Coronagraphy, Stars, Planets, James Webb Space Telescope, Point spread functions, Wavefronts, Telescopes, Space telescopes, Sensors, Diffraction

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Proceedings Article | 7 July 2006 Paper

Paper

Studying a simple TPF-C

John Krist, John Trauger, Dwight Moody

Proceedings Volume 6265, 62653O (2006) https://doi.org/10.1117/12.672386

KEYWORDS: Wavefronts, Planets, Stars, Speckle, Mirrors, Coronagraphy, Wave propagation, Actuators, Deformable mirrors, Diffraction

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Proceedings Article | 30 June 2006 Paper

Paper

Temporal optical behavior of HST: focus, coma, and astigmatism history

Matthew Lallo, Russell Makidon, Stefano Casertano, John Krist

Proceedings Volume 6270, 62701N (2006) https://doi.org/10.1117/12.672040

KEYWORDS: Monochromatic aberrations, Point spread functions, Wavefronts, Phase retrieval, Data modeling, Mirrors, Sensors, Observatories, Cameras, Phase modulation

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Proceedings Article | 30 June 2006 Paper

Paper

The temporal optical behavior of the Hubble Space Telescope: the impact on science observations

Russell Makidon, Matthew Lallo, Stefano Casertano, Ronald Gilliland, Marco Sirianni, John Krist

Proceedings Volume 6270, 62701L (2006) https://doi.org/10.1117/12.671604

KEYWORDS: Point spread functions, Monochromatic aberrations, Cameras, Mirrors, Distortion, Charge-coupled devices, Observatories, Imaging systems, Sensors, Hubble Space Telescope

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Proceedings Article | 12 October 2004 Paper

Paper

High-contrast imaging with the Hubble Space Telescope: performance and lessons learned

John Krist

Proceedings Volume 5487, (2004) https://doi.org/10.1117/12.548890

KEYWORDS: Point spread functions, Coronagraphy, Stars, Cameras, Diffraction, Telescopes, Light scattering, Planets, Mirrors, Sensors

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Proceedings Article | 29 September 2004 Paper

Paper

Position-dependent CCD charge diffusion: results from HST/ACS

John Krist

Proceedings Volume 5499, (2004) https://doi.org/10.1117/12.548889

KEYWORDS: Point spread functions, Diffusion, Charge-coupled devices, Monochromatic aberrations, Cameras, Sensors, Stars, Electrodes, CCD cameras, Data modeling

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Proceedings Article | 5 March 2003 Paper

Paper

NIRCAM image simulations for NGST wavefront sensing

Anand Sivaramakrishnan, Russell Makidon, Donald Figer, Robert Jedrzejewski, Howard Bushouse, John Krist, H.S. Stockman, Philip Hodge, Nadezhda Dencheva, Bernard Rauscher, Victoria Laidler, Catherine Ohara, David Redding, Myungshin Im, Joel Offenberg

Proceedings Volume 4850, (2003) https://doi.org/10.1117/12.461933

KEYWORDS: Sensors, Space telescopes, Stars, Point spread functions, Calibration, Wavefront sensors, Device simulation, Image segmentation, Telescopes, Electronics

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Proceedings Article | 3 March 2003 Paper

Paper

Jovian Planet Finder optical system

John Krist, Mark Clampin, Larry Petro, Robert Woodruff, Holland Ford, Garth Illingworth, Christ Ftaclas

Proceedings Volume 4860, (2003) https://doi.org/10.1117/12.457838

KEYWORDS: Mirrors, Planets, Stars, Space telescopes, Wavefronts, Light scattering, Telescopes, Coronagraphy, Polishing, Point spread functions

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Proceedings Article | 3 March 2003 Paper

Paper

Advanced camera for surveys coronagraph on the Hubble Space Telescope

John Krist, George Hartig, Mark Clampin, David Golimowski, Holland Ford, Garth Illingworth

Proceedings Volume 4860, (2003) https://doi.org/10.1117/12.457835

KEYWORDS: Coronagraphy, Stars, Point spread functions, Mirrors, Cameras, Light scattering, Light, Telescopes, Diffraction, Hubble Space Telescope

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Proceedings Article | 24 February 2003 Paper

Paper

Overview of the Advanced Camera for Surveys on-orbit performance

Holland Ford, Mark Clampin, George Hartig, Garth Illingworth, Marco Sirianni, Andre Martel, Gerhardt Meurer, William McCann, Pamela Sullivan, Frank Bartko, Narcisco Benitez, John Blakeslee, Rychard Bouwens, Tom Broadhurst, Robert Brown, Christopher Burrows, Douglas Campbell, Edward Cheng, Paul Feldman, Marijn Franx, David Golimowski, Caryl Gronwall, Randy Kimble, John Krist, Michael Lesser, Dan Magee, George Miley, Marc Postman, Marc Rafal, Piero Rosati, William Sparks, Hien Tran, Zlatan Tsvetanov, Paul Volmer, Richard White, Robert Woodruff

Proceedings Volume 4854, (2003) https://doi.org/10.1117/12.460040

KEYWORDS: Stars, Coronagraphy, Cameras, Calibration, Charge-coupled devices, Point spread functions, Galactic astronomy, Space telescopes, Optical filters, Spectral resolution

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Proceedings Article | 24 February 2003 Paper

Paper

On-orbit alignment and imaging performance of the HST Advanced Camera for Surveys

George Hartig, John Krist, Andre Martel, Holland Ford, Garth Illingworth

Proceedings Volume 4854, (2003) https://doi.org/10.1117/12.459787

KEYWORDS: Sensors, Mirrors, Monochromatic aberrations, Charge-coupled devices, Image quality, Stars, Cameras, Optical alignment, CCD image sensors, Phase retrieval

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Proceedings Article | 24 February 2003 Paper

Paper

Requirements for an optical 8-m space telescope with a MEMs deformable mirror to detect Earth-like planets around nearby stars

Holland Ford, Mark Clampin, Garth Illingworth, John Krist, Scot Olivier, Larry Petro, Gary Sommagren

Proceedings Volume 4854, (2003) https://doi.org/10.1117/12.460052

KEYWORDS: Space telescopes, Planets, Stars, Mirrors, Wavefronts, Telescopes, Deformable mirrors, Coronagraphy, Device simulation, Polishing

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Proceedings Article | 28 July 2000 Paper

Paper

Performance of HST as an infrared telescope

Massimo Robberto, Anand Sivaramakrishnan, John Bacinski, Daniela Calzetti, John Krist, John MacKenty, J. Piquero, Massimo Stiavelli

Proceedings Volume 4013, (2000) https://doi.org/10.1117/12.394037

KEYWORDS: Mirrors, Telescopes, Space telescopes, Sensors, Cameras, Optical filters, Data modeling, Temperature metrology, Infrared telescopes, Thermography

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Showing 5 of 99 publications

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