Search Results - "Keller, Christoph U"

Improved Companion Mass Limits for Sirius A with Thermal Infrared Coronagraphy Using a Vector-apodizing Phase Plate and Time-domain Starlight-subtraction Techniques by Long, Joseph D., Males, Jared R., Haffert, Sebastiaan Y., Pearce, Logan, Marley, Mark S., Morzinski, Katie M., Close, Laird M., Otten, Gilles P. P. L., Snik, Frans, Kenworthy, Matthew A., Keller, Christoph U., Hinz, Philip, Monnier, John D., Weinberger, Alycia, Tolls, Volker

“…Abstract We use observations with the infrared-optimized Magellan Adaptive Optics (MagAO) system and Clio camera in 3.9 μ m light to place stringent mass…”
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Mapping atmospheric aerosols with a citizen science network of smartphone spectropolarimeters by Snik, Frans, Rietjens, Jeroen H. H., Apituley, Arnoud, Volten, Hester, Mijling, Bas, Di Noia, Antonio, Heikamp, Stephanie, Heinsbroek, Ritse C., Hasekamp, Otto P., Smit, J. Martijn, Vonk, Jan, Stam, Daphne M., van Harten, Gerard, de Boer, Jozua, Keller, Christoph U.

“…To assess the impact of atmospheric aerosols on health, climate, and air traffic, aerosol properties must be measured with fine spatial and temporal sampling…”
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Optimization-based wavefront sensorless adaptive optics for multiphoton microscopy by Antonello, Jacopo, van Werkhoven, Tim, Verhaegen, Michel, Truong, Hoa H, Keller, Christoph U, Gerritsen, Hans C

“…Optical aberrations have detrimental effects in multiphoton microscopy. These effects can be curtailed by implementing model-based wavefront sensorless…”
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Planetary science: In search of biosignatures by Keller, Christoph U, Stam, Daphne M

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Semidefinite programming for model-based sensorless adaptive optics by Antonello, Jacopo, Verhaegen, Michel, Fraanje, Rufus, van Werkhoven, Tim, Gerritsen, Hans C, Keller, Christoph U

“…Wavefront sensorless adaptive optics methodologies are widely considered in scanning fluorescence microscopy where direct wavefront sensing is challenging. In…”
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ON-SKY PERFORMANCE ANALYSIS OF THE VECTOR APODIZING PHASE PLATE CORONAGRAPH ON MagAO/Clio2 by Otten, Gilles P. P. L., Snik, Frans, Kenworthy, Matthew A., Keller, Christoph U., Males, Jared R., Morzinski, Katie M., Close, Laird M., Codona, Johanan L., Hinz, Philip M., Hornburg, Kathryn J., Brickson, Leandra L., Escuti, Michael J.

“…ABSTRACT We report on the performance of a vector apodizing phase plate coronagraph that operates over a wavelength range of 2-5 m and is installed in…”
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Towards real-time contrast control for direct exoplanet imaging with adaptive optics by Radhakrishnan, Vikram M., Keller, Christoph U., Doelman, Niek J.

“…Adaptive Optics (AO) is a crucial ingredient for diffraction-limited imaging in science and engineering. While most AO control is linear, non-linear approaches…”
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Evaluation of Phase-Diversity Techniques for Solar-Image Restoration by Paxman, Richard G., Seldin, John H., Loefdahl, Mats G., Scharmer, Goeran B., Keller, Christoph U.

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A long way off by Keller, Christoph U

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In search of biosignatures by Keller, Christoph U., Stam, Daphne M.

“…An analysis of the intensity and polarization of sunlight reflected by Earth reveals signatures of life on our planet. What prospects are there for using…”
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Detailed study of a rare hyperluminous rotating disk in an Einstein ring 10 billion years ago by Liu, Daizhong, Förster Schreiber, Natascha M., Harrington, Kevin C., Lee, Lilian L., Kamieneski, Patrick S., Davies, Richard I., Lutz, Dieter, Renzini, Alvio, Wuyts, Stijn, Tacconi, Linda J., Genzel, Reinhard, Burkert, Andreas, Herrera-Camus, Rodrigo, Alcalde Pampliega, Belén, Vishwas, Amit, Kaasinen, Melanie, Wang, Q. Daniel, Jiménez-Andrade, Eric F., Lowenthal, James, Foo, Nicholas, Frye, Brenda L., Shangguan, Jinyi, Cao, Yixian, Agapito, Guido, Berbel, Alex Agudo, Barfety, Capucine, Baruffolo, Andrea, Berman, Derek, Black, Martin, Bonaglia, Marco, Briguglio, Runa, Carbonaro, Luca, Chapman, Lee, Chen, Jianhang, Cikota, Aleksandar, Concas, Alice, Cooper, Olivia, Cresci, Giovanni, Dallilar, Yigit, Deysenroth, Matthias, Di Antonio, Ivan, Di Cianno, Amico, Di Rico, Gianluca, Doelman, David, Dolci, Mauro, Eisenhauer, Frank, Espejo, Juan, Esposito, Simone, Fantinel, Daniela, Ferruzzi, Debora, Feuchtgruber, Helmut, Gao, Xiaofeng, Garcia Diaz, Carlos, Gillessen, Stefan, Grani, Paolo, Hartl, Michael, Henry, David, Huber, Heinrich, Jolly, Jean-Baptiste, Keller, Christoph U., Kenworthy, Matthew, Kravchenko, Kateryna, Lee, Minju M., Lightfoot, John, Lunney, David, Macintosh, Mike, Mannucci, Filippo, Ott, Thomas, Pascale, Massimo, Pastras, Stavros, Pearson, David, Puglisi, Alfio, Pulsoni, Claudia, Rabien, Sebastian, Rau, Christian, Riccardi, Armando, Salasnich, Bernardo, Shimizu, Taro, Snik, Frans, Sturm, Eckhard, Taylor, William, Valentini, Angelo, Waring, Christopher, Wiezorrek, Erich, Xompero, Marco, Yun, Min S.

“…Hyperluminous infrared galaxies (HyLIRGs) are the rarest and most extreme starbursts and found only in the distant Universe ( z  ≳ 1). They have intrinsic…”
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Using the generalised-optical differentiation wavefront sensor for laser guide star wavefront sensing by Haffert, Sebastiaan Y, Keller, Christoph U, Dekany, Richard

“…Laser guide stars (LGS) are used in many adaptive optics systems to extend sky coverage. The most common wavefront sensor used in combination with a LGS is a…”
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Self-optimizing adaptive optics control with Reinforcement Learning for high-contrast imaging by Landman, Rico, Haffert, Sebastiaan Y, Radhakrishnan, Vikram M, Keller, Christoph U

“…Current and future high-contrast imaging instruments require extreme adaptive optics (XAO) systems to reach contrasts necessary to directly image exoplanets…”
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Self-optimizing adaptive optics control with Reinforcement Learning by Landman, Rico, Haffert, Sebastiaan Y, Radhakrishnan, Vikram M, Keller, Christoph U

“…Current and future high-contrast imaging instruments require extreme Adaptive Optics (XAO) systems to reach contrasts necessary to directly image exoplanets…”
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Spectropolarimetry of life: airborne measurements from a hot air balloon by Mulder, Willeke, Patty, C. H. Lucas, Spadaccia, Stefano, Pommerol, Antoine, Demory, Brice-Olivier, Keller, Christoph U, Kühn, Jonas G, Snik, Frans, Stam, Daphne M

“…Does life exist outside our Solar System? A first step towards searching for life outside our Solar System is detecting life on Earth by using remote sensing…”
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Spatial polarization modulators: distinguishing diffraction effects from spatial polarization modulation by Mulder, Willeke, Doelman, David S, Keller, Christoph U, Patty, C. H. Lucas, Snik, Frans

“…Proc. SPIE 11833, Polarization Science and Remote Sensing X, 118330M (1 August 2021) Are we alone? In our quest to find life beyond Earth, we use our own…”
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Rigorous vector wave propagation for arbitrary flat media by Bos, Steven P, Haffert, Sebastiaan Y, Keller, Christoph U

“…Proceedings Volume 10407, Polarization Science and Remote Sensing VIII; 1040709 (2017) Precise modelling of the (off-axis) point spread function (PSF) to…”
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A universal smartphone add-on for portable spectroscopy and polarimetry: iSPEX 2 by Burggraaff, Olivier, Perduijn, Armand B, van Hek, Robert F, Schmidt, Norbert, Keller, Christoph U, Snik, Frans

“…Proc. SPIE 11389, Micro- and Nanotechnology Sensors, Systems, and Applications XII, 113892K (20 May 2020) Spectropolarimetry is a powerful technique for remote…”
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Sterrekundig Instituut Utrecht: The Last Years by Keller, Christoph U

“…I describe the last years of the 370-year long life of the Sterrekundig Instituut Utrecht, which was the second-oldest university observatory in the world and…”
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Improved companion mass limits for Sirius A with thermal infrared coronagraphy using a vector-apodizing phase plate and time-domain starlight-subtraction techniques by Long, Joseph D, Males, Jared R, Haffert, Sebastiaan Y, Pearce, Logan, Marley, Mark S, Morzinski, Katie M, Close, Laird M, Otten, Gilles P. P. L, Snik, Frans, Kenworthy, Matthew A, Keller, Christoph U, Hinz, Philip, Monnier, John D, Weinberger, Alycia, Tolls, Volker

“…We use observations with the infrared-optimized MagAO system and Clio camera in 3.9 $\mu$m light to place stringent mass constraints on possible undetected…”
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