Results 51 to 60 of about 1,731,322 (198)

Gaussian coronagraphic mask report and AIV procedure

, 2021
The document outlines the testing and alignment procedures for the Gaussian coronagraphic mask used in the SHARK-NIR instrument, highlighting the critical role of these processes in enhancing the instrument's high-contrast imaging capabilities for ...
E. Carolo, G. Umbriaco, D. Vassallo
core   +1 more source

Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star HIP 39017

The Astronomical Journal
We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, γ Doradus ( γ Dor)-type variable star HIP 39017 (HD 65526). The companion’s SCExAO/CHARIS JHK (1.1–2.4 μ m) spectrum and Keck/NIRC2
Taylor L. Tobin, Thayne Currie, Yiting Li, Jeffrey Chilcote, Timothy D. Brandt, Brianna Lacy, Masayuki Kuzuhara, Maria Vincent, Mona El Morsy, Vincent Deo, Jonathan P. Williams, Olivier Guyon, Julien Lozi, Sebastien Vievard, Nour Skaf, Kyohoon Ahn, Tyler Groff, N. Jeremy Kasdin, Taichi Uyama, Motohide Tamura, Aidan Gibbs, Briley L. Lewis, Rachel Bowens-Rubin, Maïssa Salama, Qier An, Minghan Chen   +25 more
doaj   +1 more source

Collection, Collation, and Comparison of 3D Coronal CME Reconstructions

Space Weather, Volume 22, Issue 1, January 2024.
Abstract Predicting the impacts of coronal mass ejections (CMEs) is a major focus of current space weather forecasting efforts. Typically, CME properties are reconstructed from stereoscopic coronal images and then used to forward model a CME's interplanetary evolution.
C. Kay, E. Palmerio
wiley   +1 more source

Improved Companion Mass Limits for Sirius A with Thermal Infrared Coronagraphy Using a Vector-apodizing Phase Plate and Time-domain Starlight-subtraction Techniques

The Astronomical Journal, 2023
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 constraints on possible undetected companions to Sirius A.
Joseph D. Long, Jared R. Males, Sebastiaan Y. Haffert, Logan Pearce, Mark S. Marley, Katie M. Morzinski, Laird M. Close, Gilles P. P. L. Otten, Frans Snik, Matthew A. Kenworthy, Christoph U. Keller, Philip Hinz, John D. Monnier, Alycia Weinberger, Volker Tolls   +14 more
doaj   +1 more source

Focal plane wavefront control with model-based reinforcement learning

Astronomy & Astrophysics
Context. The direct imaging of potentially habitable exoplanets is one prime science case for high-contrast imaging (HCI) instruments on ground-based, extremely large telescopes.
Nousiainen J., Taskin I., Kasper M., Orban de Xivry G., Absil O.   +4 more
doaj   +1 more source

Automated alignment and on-sky performance of the Gemini planet imager coronagraph [PDF]

SPIE Proceedings, 2014
The Gemini Planet Imager (GPI) is a next-generation, facility instrument currently being commissioned at the Gemini South observatory. GPI combines an extreme adaptive optics system and integral field spectrograph (IFS) with an apodized-pupil Lyot coronagraph (APLC) producing an unprecedented capability for directly imaging and spectroscopically ...
Savransky, Dmitry, Thomas, Sandrine J., Poyneer, Lisa A., Dunn, Jennifer, Macintosh, Bruce A., Sadakuni, Naru, Dillon, Daren, Goodsell, Stephen J., Hartung, Markus, Hibon, Pascale, Rantakyrö, Fredrik, Cardwell, Andrew, Serio, Andrew, team, with the GPI   +13 more
openaire   +2 more sources

A Coronagraphic Pilot Study of the Circumstellar Environments around Red Supergiants: CD -31°4916’s Dust Morphology

The Astronomical Journal
Many mechanisms have been proposed to contribute to massive-star mass loss, but in general little is known about the physics involved. Studies of circumstellar environments around massive stars might help to determine which mechanisms are the most common.
Jamie R. Lomax, Emily M. Levesque, John P. Wisniewski, John H. Debes   +3 more
doaj   +1 more source

The Effect of Spectral Resolution on Biosignature Detection via Reflected-light Observations of the Earth through Time

The Astrophysical Journal
NASA’s Habitable Worlds Observatory (HWO) will search for biosignatures on Earth-like exoplanets using reflected light spectroscopy. A critical instrument design parameter is resolving power, which must balance biosignature detectability against exposure
Samantha Gilbert-Janizek, Jacob Lustig-Yaeger, Joshua Krissansen-Totton   +2 more
doaj   +1 more source

First Metis Detection of the Helium D3 Line Polarization in a Large Eruptive Prominence

The Astrophysical Journal Letters, 2023
Metis on board Solar Orbiter is the space coronagraph developed by an Italian–German–Czech consortium. It is capable of observing solar corona and various coronal structures in the visible-light (VL) and UV (hydrogen Ly α ) channels simultaneously for ...
Petr Heinzel, Sonja Jejčič, Jiří Štěpán, Roberto Susino, Vincenzo Andretta, Giuliana Russano, Silvano Fineschi, Marco Romoli, Alessandro Bemporad, Arkadiusz Berlicki, Aleksandr Burtovoi, Vania Da Deppo, Yara De Leo, Catia Grimani, Giovanna Jerse, Federico Landini, Giampiero Naletto, Gianalfredo Nicolini, Maurizio Pancrazzi, Tanausú del Pino Alemán, Clementina Sasso, Daniele Spadaro, Marco Stangalini, Daniele Telloni, Luca Teriaca, Michela Uslenghi, Andrés Vicente Arévalo   +26 more
doaj   +1 more source

Computer vision applications for coronagraphic optical alignment and image processing [PDF]

Applied Optics, 2013
24 pages, 8 grayscale ...
Savransky, Dmitry, Thomas, Sandrine J., Poyneer, Lisa A., Macintosh, Bruce A.   +3 more
openaire   +3 more sources