Results 31 to 40 of about 345,237 (255)

The PRIMA fringe sensor unit [PDF]

, 2009
The Fringe Sensor Unit (FSU) is the central element of the Phase Referenced Imaging and Micro-arcsecond Astrometry (PRIMA) dual-feed facility and provides fringe sensing for all observation modes, comprising off-axis fringe tracking, phase referenced ...
Barry, Bean, Benedict, Bonnet, Colavita, Colavita, Colavita, Daigne, F. Delplancke, J. Sahlmann, Lane, Lane, Lane, Le Bouquin, Le Bouquin, Leinert, Lindegren, Linfield, Lévêque, M. Accardo, Monnier, Muterspaugh, Muterspaugh, Petrov, Pravdo, R. Abuter, S. Mottini, S. Ménardi, Shao, Shao, Shao, Tango, van Belle, Wyant   +33 more
core   +2 more sources

Hierarchical fringe tracking

, 2014
The limiting magnitude is a key issue for optical interferometry. Pairwise fringe trackers based on the integrated optics concepts used for example in GRAVITY seem limited to about K=10.5 with the 8m Unit Telescopes of the VLTI, and there is a general ...
Benkhaldoum, Zouhair, Boskri, Abdelkarim, Bresson, Yves, Elhalkouj, Thami, Folcher, Jean-Pierre, Lagarde, Stephane, Lazrek, Mohamed, Petrov, Romain G., Rakshit, Suvendu   +8 more
core   +1 more source

Single conjugate adaptive optics for the ELT instrument METIS [PDF]

, 2018
The ELT is a 39m large, ground-based optical and near- to mid-infrared telescope under construction in the Chilean Atacama desert. Operation is planned to start around the middle of the next decade.
Absil, Olivier, Bertram, Thomas, Brandner, Wolfgang, Cantalloube, Faustine, Carlomagno, Brunella, Feldt, Markus, Hippler, Stefan, Obereder, Andreas, Shatokhina, Iuliia, Stuik, Remko   +9 more
core   +3 more sources

P-REx: The Piston Reconstruction Experiment for Infrared Interferometry

, 2017
For sensitive infrared interferometry, it is crucial to control the differential piston evolution between the used telescopes. This is classically done by the use of a fringe tracker.
Pott, Jörg-Uwe, Velasco, Sergio, Widmann, Felix   +2 more
core   +1 more source

Nulling interferometry: performance comparison between Antarctica and other ground-based sites [PDF]

, 2007
Detecting the presence of circumstellar dust around nearby solar-type main sequence stars is an important pre-requisite for the design of future life-finding space missions such as ESA's Darwin or NASA's Terrestrial Planet Finder (TPF).
Absil, Absil, Agabi, Aristidi, Aristidi, Beichman, Bussmann, Candidi, Chamberlain, Chamberlin, Colavita, Conan, Fridlund, Gondoin, Kaltenegger, Kasting, Kelsall, Lawrence, Lawrence, Lay, M. Barillot, M. R. Swain, Marks, Marks, Mennesson, O. Absil, Racine, Serabyn, Swain, Swain, Travouillon, V. Coudé du Foresto   +31 more
core   +5 more sources

Atmospheric tomography with separate minimum variance laser and natural guide star mode control [PDF]

, 2009
This paper introduces a novel, computationally efficient, and practical atmospheric tomography wavefront control architecture with separate minimum variance laser and natural guide star mode estimation.
Ellerbroek, B. L., Gilles, L.
core   +1 more source

Sensing and control of segmented mirrors with a pyramid wavefront sensor in the presence of spiders

, 2017
The segmentation of the telescope pupil (by spiders & the segmented M4) create areas of phase isolated by the width of the spiders on the wavefront sensor (WFS), breaking the spatial continuity of the wavefront.
Clarke, Fraser, Correia, Carlos, Dohlen, Kjetil, Fusco, Thierry, Hadi, Kacem El, Paufique, Jérome, Petit, Cyril, Quiros-Pacheco, Fernando, Sauvage, Jean-François, Schwartz, Noah, Thatte, Niranjan, Vernet, Joel   +11 more
core   +1 more source

Control and Alignment of Segmented-Mirror Telescopes: Matrices, Modes, and Error Propagation [PDF]

, 2004
Starting from the successful Keck telescope design, we construct and analyze the control matrix for the active control system of the primary mirror of a generalized segmented-mirror telescope, with up to 1000 segments and including an alternative sensor ...
Chanan, Gary, MacMartin, Douglas G., Mast, Terry, Nelson, Jerry   +3 more
core   +1 more source

Free‐Form Microfluidic Microneedle Array Patches

Advanced Functional Materials, EarlyView.
Microfluidic microneedle array patches (MAPs) integrate hollow microneedles with embedded microfluidic channels, fabricated using high‐resolution 3D printing, to enable controlled transdermal delivery of liquid, mixed, or reconstituted therapeutics.
Ian A. Coates, Madison M. Driskill, Netra U. Rajesh, Gabriel Lipkowitz, Dan Ilyn, Yue Xu, Maria T. Dulay, Gunilla B. Jacobson, John R. Tumbleston, Jillian L. Perry, Shaomin Tian, Joseph M. DeSimone   +11 more
wiley   +1 more source

Stroke saturation on a MEMS deformable mirror for woofer-tweeter adaptive optics

, 2009
High-contrast imaging of extrasolar planet candidates around a main-sequence star has recently been realized from the ground using current adaptive optics (AO) systems. Advancing such observations will be a task for the Gemini Planet Imager, an upcoming "
Bruce Macintosh, Conan, Conan, Daren Dillon, Donald Gavel, Evans, Evans, Evans, Gavel, Gavel, Hardy, Hudgin, Kalas, Katie Morzinski, Lagrange, Lavigne, Macintosh, Malbet, Marois, Marois, Morzinski, Morzinski, Morzinski, Noll, Norton, Severson, Sommargren, Soummer, Stewart, Thomas, Vogel   +30 more
core   +1 more source