Dr. Charles D. Dowell Profile

Dr. Charles D. Dowell

Research Scientist at Jet Propulsion Lab

SPIE Involvement:

Author

Publications (38)

Proceedings Article | 29 August 2022 Presentation

Spectral calibration of SPHEREx focal plane

Howard Hui, James Bock, Sam Condon, Charles Dowell, Matt Hollister, Phil Korngut, Ken Manatt, Chi Nguyen, Hien Nguyen, Steve Padin, Marco Viero

Proceedings Volume 12180, 121801J (2022) https://doi.org/10.1117/12.2628636

KEYWORDS: Spectral calibration, Sensors, Staring arrays, Spectroscopy, Spectral resolution, Ranging, Optical filters, Near infrared, Linear filtering, Integrating spheres

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Proceedings Article | 13 December 2020 Presentation + Paper

SPHEREx: NASA's near-infrared spectrophotometric all-sky survey

Brendan Crill, Michael Werner, Rachel Akeson, Matthew Ashby, Lindsey Bleem, James Bock, Sean Bryan, Jill Burnham, Joyce Byunh, Tzu-Ching Chang, Yi-Kuan Chiang, Walter Cook, Asantha Cooray, Andrew Davis, OIivier Doré, C. Darren Dowell, Gregory Dubois-Felsmann, Tim Eifler, Andreas Faisst, Salman Habib, Chen Heinrich, Katrin Heitmann, Grigory Heaton, Christopher Hirata, Viktor Hristov, Howard Hui, Woong-Seob Jeong, Jae Hwan Kang, Branislav Kecman, J. Davy Kirkpatrick, Phillip Korngut, Elisabeth Krause, Bomee Lee, Carey Lisse, Daniel Masters, Philip Mauskopf, Gary Melnick, Hiromasa Miyasaka, Hooshang Nayyeri, Hien Nguyen, Karin Öberg, Steve Padin, Roberta Paladini, Milad Pourrahmani, Jeonghyun Pyo, Roger Smith, Yong-Seong Song, Teresa Symons, Harry Teplitz, Volker Tolls, Steve Unwin, Rogier Windhorst, Yujin Yang, Michael Zemcov

Proceedings Volume 11443, 114430I (2020) https://doi.org/10.1117/12.2567224

KEYWORDS: Galactic astronomy, Telescopes, Astrophysics, Spectral resolution, Absorption, Stars, Spectroscopes, Detector arrays, Beam splitters, Optical filters

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Proceedings Article | 19 August 2014 Paper

SWCam: the short wavelength camera for the CCAT Observatory

Gordon Stacey, Stephen Parshley, Thomas Nikola, German Cortes-Medellin, Justin Schoenwald, Ganesh Rajagopalan, Michael Niemack, Tim Jenness, Patricio Gallardo, Brian Koopman, Charles Dowell, Peter Day, Matthew Hollister, Attila Kovacs, Henry LeDuc, Christopher McKenney, Ryan Monroe, Hiroshige Yoshida, Jonas Zmuidzinas, Loren Swenson, Simon Radford, Hien Trong Nguyen, Anthony Mroczkowski, Jason Glenn, Jordan Wheeler, Philip Maloney, Spencer Brugger, Joseph Adams, Frank Bertoldi, Reinhold Schaaf, Mark Halpern, Douglas Scott, Galen Marsden, Jack Sayers, Scott Chapman, Joaquin Vieira

Proceedings Volume 9153, 91530L (2014) https://doi.org/10.1117/12.2057101

KEYWORDS: Cameras, Galactic astronomy, Sensors, Silicon, Stars, Thin film coatings, Telescopes, Deep reactive ion etching, Surface conduction electron emitter displays, Observatories

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We describe the Short Wavelength Camera (SWCam) for the CCAT observatory including the primary science drivers, the coupling of the science drivers to the instrument requirements, the resulting implementation of the design, and its performance expectations at first light. CCAT is a 25 m submillimeter telescope planned to operate at 5600 meters, near the summit of Cerro Chajnantor in the Atacama Desert in northern Chile. CCAT is designed to give a total wave front error of 12.5 μm rms, so that combined with its high and exceptionally dry site, the facility will provide unsurpassed point source sensitivity deep into the short submillimeter bands to wavelengths as short as the 200 μm telluric window. The SWCam system consists of 7 sub-cameras that address 4 different telluric windows: 4 subcameras at 350 μm, 1 at 450 μm, 1 at 850 μm, and 1 at 2 mm wavelength. Each sub-camera has a 6’ diameter field of view, so that the total instantaneous field of view for SWCam is equivalent to a 16’ diameter circle. Each focal plane is populated with near unit filling factor arrays of Lumped Element Kinetic Inductance Detectors (LEKIDs) with pixels scaled to subtend an solid angle of (λ/D)2 on the sky. The total pixel count is 57,160. We expect background limited performance at each wavelength, and to be able to map < 35(°)2 of sky to 5 σ on the confusion noise at each wavelength per year with this first light instrument. Our primary science goal is to resolve the Cosmic Far-IR Background (CIRB) in our four colors so that we may explore the star and galaxy formation history of the Universe extending to within 500 million years of the Big Bang. CCAT's large and high-accuracy aperture, its fast slewing speed, use of instruments with large format arrays, and being located at a superb site enables mapping speeds of up to three orders of magnitude larger than contemporary or near future facilities and makes it uniquely sensitive, especially in the short submm bands.

Proceedings Article | 19 August 2014 Paper

Keck array and BICEP3: spectral characterization of 5000+ detectors

K. Karkare, P. A. Ade, Z. Ahmed, R. Aikin, K. Alexander, M. Amiri, D. Barkats, S. Benton, C. Bischoff, J. Bock, J. Bonetti, J. Brevik, I. Buder, E. Bullock, B. Burger, J. Connors, B. Crill, G. Davis, C. Dowell, L. Duband, J. Filippini, S. Fliescher, S. Golwala, M. Gordon, J. Grayson, M. Halpern, M. Hasselfield, S. Hildebrandt, G. Hilton, V. Hristov, H. Hui, K. Irwin, J. Kang, E. Karpel, S. Kefeli, S. Kernasovskiy, J. Kovac, C. Kuo, E. Leitch, M. Lueker, P. Mason, K. Megerian, C. Netterfield, H. Nguyen, R. O'Brient, R. Ogburn, C. Pryke, C. Reintsema, S. Richter, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, K. Thompson, J. Tolan, A. Turner, A. Vieregg, A. Weber, C. Wong, W. L. Wu, K. Yoon

Proceedings Volume 9153, 91533B (2014) https://doi.org/10.1117/12.2056779

KEYWORDS: Sensors, Receivers, Fourier transforms, Polarization, Atmospheric modeling, Calibration, Atmospheric sensing, Signal detection, Physics, Microwave radiation

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Proceedings Article | 19 August 2014 Paper

BICEP2 and Keck array: upgrades and improved beam characterization

I. Buder, P. A. Ade, Z. Ahmed, R. Aikin, K. Alexander, M. Amiri, D. Barkats, S. Benton, C. Bischoff, J. Bock, J. Bonetti, J. Brevik, E. Bullock, B. Burger, B. Crill, G. Davis, C. Dowell, L. Duband, J. Filippini, S. Fliescher, S. Golwala, M. Gordon, M. Halpern, M. Hasselfield, S. Hildebrandt, G. Hilton, V. Hristov, H. Hui, K. Irwin, K. Karkare, J. Kaufman, B. Keating, S. Kefeli, S. Kernasovskiy, J. Kovac, C. Kuo, E. Leitch, M. Lueker, P. Mason, K. Megerian, C. Netterfield, H. Nguyen, R. O’Brient, R. Ogburn, A. Orlando, C. Pryke, C. Reintsema, S. Richter, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, K. Thompson, J. Tolan, A. Turner, A. Vieregg, A. Weber, D. Wiebe, P. Wilson, C. Wong, K. Yoon

Proceedings Volume 9153, 915312 (2014) https://doi.org/10.1117/12.2055713

KEYWORDS: Telescopes, Sensors, Polarization, Receivers, Microwave radiation, Mirrors, Physics, Space telescopes, Optical testing, Optical simulations

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Proceedings Article | 31 July 2014 Paper

SOFIA science instruments: commissioning, upgrades and future opportunities

Erin Smith, John Miles, L. Andrew Helton, Ravi Sankrit, B. Andersson, Eric Becklin, James De Buizer, C. Dowell, Edward Dunham, Rolf Güsten, Doyal Harper, Terry Herter, Luke Keller, Randolf Klein, Alfred Krabbe, Sarah Logsdon, Pamela Marcum, Ian McLean, William Reach, Matthew Richter, Thomas Roellig, Göran Sandell, Maureen Savage, Pasquale Temi, William Vacca, John Vaillancourt, Jeffrey Van Cleve, Erick Young

Proceedings Volume 9147, 914706 (2014) https://doi.org/10.1117/12.2056942

KEYWORDS: Spectroscopy, Observatories, Imaging spectroscopy, Infrared spectroscopy, Sensors, Infrared cameras, Spectroscopes, Cameras, Radio astronomy, Astronomy

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Proceedings Article | 23 July 2014 Paper

Antireflection coatings for submillimeter silicon lenses

Jordan Wheeler, Brian Koopman, Patricio Gallardo, Philip Maloney, Spencer Brugger, German Cortes-Medellin, Rahul Datta, C. Darren Dowell, Jason Glenn, Sunil Golwala, Chris McKenney, Jeffery McMahon, Charles Munson, Mike Niemack, Stephen Parshley, Gordon Stacey

Proceedings Volume 9153, 91532Z (2014) https://doi.org/10.1117/12.2057011

KEYWORDS: Silicon, Antireflective coatings, Coating, Terahertz radiation, Deep reactive ion etching, Lenses, Dielectrics, Absorption, Interfaces, Etching

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Proceedings Article | 19 September 2013 Paper

Capabilities, performance, and status of the SOFIA science instrument suite

John Miles, L. Andrew Helton, Ravi Sankrit, B. Andersson, E. Becklin, James De Buizer, C. Dowell, Edward Dunham, Rolf Güsten, Doyal Harper, Terry Herter, Luke Keller, Randolf Klein, Alfred Krabbe, Pamela Marcum, Ian McLean, William Reach, Matthew Richter, Thomas Roellig, Göran Sandell, Maureen Savage, Erin Smith, Pasquale Temi, William Vacca, John Vaillancourt, Jeffery Van Cleve, Erick Young, Peter Zell

Proceedings Volume 8867, 88670N (2013) https://doi.org/10.1117/12.2022791

KEYWORDS: Spectroscopy, Telescopes, Observatories, Stars, Sensors, Imaging systems, Astronomy, Photometry, Infrared telescopes, Infrared radiation

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Proceedings Article | 27 September 2012 Paper

Optimization and sensitivity of the Keck array

S. Kernasovskiy, P. A. R. Ade, R. Aikin, M. Amiri, S. Benton, C. Bischoff, J. Bock, J. Bonetti, J. Brevik, B. Burger, G. Davis, C. Dowell, L. Duband, J. Filippini, S. Fliescher, S. Golwala, M. Halpern, M. Hasselfield, G. Hilton, V. Hristov, K. Irwin, J. Kovac, C. Kuo, E. Leitch, M. Lueker, C. Netterfield, H. Nguyen, R. O'Brient, R. Ogburn, C. Pryke, C. Reintsema, J. Ruhl, M. Runyan, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, J. Tolan, A. Turner, A. Vieregg, D. Wiebe, P. Wilson, C. Wong

Proceedings Volume 8452, 84521B (2012) https://doi.org/10.1117/12.926934

KEYWORDS: Sensors, Polarization, Multiplexing, Receivers, Telescopes, Calibration, Resistance, Servomechanisms, Switches, Phonons

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Proceedings Article | 27 September 2012 Paper

BICEP2 and Keck Array operational overview and status of observations

R. Ogburn, P. A. Ade, R. Aikin, M. Amiri, S. Benton, C. Bischoff, J. Bock, J. Bonetti, J. Brevik, E. Bullock, B. Burger, G. Davis, C. Dowell, L. Duband, J. Filippini, S. Fliescher, S. Golwala, M. Gordon, M. Halpern, M. Hasselfield, G. Hilton, V. Hristov, H. Hui, K. Irwin, J. Kaufman, B. Keating, S. Kernasovskiy, J. Kovac, C. Kuo, E. Leitch, M. Lueker, T. Montroy, C. Netterfield, H. Nguyen, R. O'Brient, A. Orlando, C. Pryke, C. Reintsema, S. Richter, J. Ruhl, M. Runyan, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, K. Thompson, J. Tolan, A. Turner, A. Vieregg, D. Wiebe, P. Wilson, C. Wong

Proceedings Volume 8452, 84521A (2012) https://doi.org/10.1117/12.925731

KEYWORDS: Sensors, Receivers, Multiplexing, Polarization, Telescopes, Staring arrays, Microwave radiation, Liquids, Helium, Cryogenics

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Proceedings Article | 27 September 2012 Paper

Antenna-coupled TES bolometers for the Keck array, Spider, and Polar-1

R. O'Brient, P. A. Ade, Z. Ahmed, R. Aikin, M. Amiri, S. Benton, C. Bischoff, J. Bock, J. Bonetti, J. Brevik, B. Burger, G. Davis, P. Day, C. Dowell, L. Duband, J. Filippini, S. Fliescher, S. Golwala, J. Grayson, M. Halpern, M. Hasselfield, G. Hilton, V. Hristov, H. Hui, K. Irwin, S. Kernasovskiy, J. Kovac, C. Kuo, E. Leitch, M. Lueker, K. Megerian, L. Moncelsi, C. Netterfield, H. Nguyen, R. Ogburn, C. Pryke, C. Reintsema, J. Ruhl, M. Runyan, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, J. Tolan, A. Turner, R. Tucker, A. Vieregg, D. Wiebe, P. Wilson, C. Wong, W. L. Wu, K. Yoon

Proceedings Volume 8452, 84521G (2012) https://doi.org/10.1117/12.927214

KEYWORDS: Polarization, Antennas, Niobium, Sensors, Bolometers, Cameras, Phased array optics, Near field, Scattering, Physics

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Proceedings Article | 24 September 2012 Paper

MAKO: a pathfinder instrument for on-sky demonstration of low-cost 350 micron imaging arrays

Loren Swenson, Peter Day, Charles Dowell, Byeong Eom, Matthew Hollister, Robert Jarnot, Attila Kovács, Henry Leduc, Christopher McKenney, Ryan Monroe, Tony Mroczkowski, Hien Nguyen, Jonas Zmuidzinas

Proceedings Volume 8452, 84520P (2012) https://doi.org/10.1117/12.926223

KEYWORDS: Sensors, Multiplexing, Resonators, Superconductors, Head, Amplifiers, Optical filters, Imaging arrays, Microresonators, Detector arrays

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Proceedings Article | 24 September 2012 Paper

Optical characterization of the Keck array polarimeter at the South Pole

A. G. Vieregg, P. A. R. Ade, R. Aikin, C. Bischoff, J. J. Bock, J. A. Bonetti, K. J. Bradford, J. A. Brevik, C. D. Dowell, L. Duband, J. P. Filippini, S. Fliescher, S. R. Golwala, M. S. Gordon, M. Halpern, G. Hilton, V. V. Hristov, K. Irwin, S. Kernasovskiy, J. M. Kovac, C. L. Kuo, E. Leitch, M. Lueker, T. Montroy, C. B. Netterfield, H. T. Nguyen, R. O'Brient, R. W. Ogburn, C. Pryke, J. E. Ruhl, M. Runyan, R. Schwarz, C. Sheehy, Z. Staniszewski, R. Sudiwala, G. Teply, J. Tolan, A. D. Turner, P. Wilson, C. L. Wong

Proceedings Volume 8452, 845226 (2012) https://doi.org/10.1117/12.926639

KEYWORDS: Sensors, Receivers, Polarization, Optical testing, Microwave radiation, Mirrors, Polarimetry, Control systems, Beam shaping, Telescopes

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Proceedings Article | 11 August 2010 Paper

Status of the SPIRE photometer data processing pipelines during the early phases of the Herschel Mission

C. Darren Dowell, Michael Pohlen, Chris Pearson, Matt Griffin, Tanya Lim, George Bendo, Dominique Benielli, James Bock, Pierre Chanial, Dave Clements, Luca Conversi, Marc Ferlet, Trevor Fulton, Rene Gastaud, Jason Glenn, Tim Grundy, Steve Guest, Ken King, Sarah Leeks, Louis Levenson, Nanyao Lu, Huw Morris, Hien Nguyen, Brian O'Halloran, Seb Oliver, Pasquale Panuzzo, Andreas Papageorgiou, Edward Polehampton, Dimitra Rigopoulou, Helene Roussel, Nicola Schneider, Bernhard Schulz, Arnold Schwartz, David Shupe, Bruce Sibthorpe, Sunil Sidher, Anthony Smith, Bruce Swinyard, Markos Trichas, Ivan Valtchanov, Adam Woodcraft, C. Kevin Xu, Lijun Zhang

Proceedings Volume 7731, 773136 (2010) https://doi.org/10.1117/12.858035

KEYWORDS: Sensors, Bolometers, Photometry, Calibration, Signal detection, Telescopes, Space telescopes, Data processing, Astronomy, Detector arrays

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Proceedings Article | 6 August 2010 Paper

Optical design of the EPIC-IM crossed Dragone telescope

Huan Tran, Brad Johnson, Mark Dragovan, James Bock, Abdullah Aljabri, Alex Amblard, Daniel Bauman, Marc Betoule, Talso Chui, Loris Colombo, Asantha Cooray, Dustin Crumb, Peter Day, Clive Dickenson, Darren Dowell, Sunil Golwala, Krzysztof Gorski, Shaul Hanany, Warren Holmes, Kent Irwin, Brian Keating, Chao-Lin Kuo, Adrian Lee, Andrew Lange, Charles Lawrence, Steve Meyer, Nate Miller, Hien Nguyen, Elena Pierpaoli, Nicolas Ponthieu, Jean-Loup Puget, Jeff Raab, Paul Richards, Celeste Satter, Mike Seiffert, Meir Shimon, Brett Williams, Jonas Zmuidzinas

Proceedings Volume 7731, 77311R (2010) https://doi.org/10.1117/12.857423

KEYWORDS: Polarization, Telescopes, Mirrors, Device simulation, Optical simulations, Optical design, Space telescopes, Sensors, Space operations, Geometrical optics

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Proceedings Article | 21 July 2010 Paper

HAWCPol: a first-generation far-infrared polarimeter for SOFIA

C. Darren Dowell, Brant Cook, D. Al Harper, Lung-Sheng Lin, Leslie Looney, Giles Novak, Ian Stephens, Marc Berthoud, David Chuss, Richard Crutcher, Jessie Dotson, Roger Hildebrand, Martin Houde, Terry Jones, Megan Krejny, Alexandre Lazarian, S. Harvey Moseley, Kostas Tassis, John Vaillancourt, Michael Werner

Proceedings Volume 7735, 77356H (2010) https://doi.org/10.1117/12.857842

KEYWORDS: Polarimetry, Polarization, Magnetism, Clouds, Cryogenics, Astronomy, Cameras, Sensors, Data analysis, Modulation

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