Results 21 to 30 of about 1,731,322 (198)

Deriving CME Density From Remote Sensing Data and Comparison to In‐Situ Measurements

Journal of Geophysical Research: Space Physics, Volume 126, Issue 1, January 2021., 2021
Abstract We determine the three‐dimensional geometry and deprojected mass of 29 well‐observed coronal mass ejections (CMEs) and their interplanetary counterparts (ICMEs) using combined Solar Terrestrial Relations Observatory ‐ Solar and Heliospheric Observatory white‐light data.
M. Temmer, L. Holzknecht, M. Dumbović, B. Vršnak, N. Sachdeva, S. G. Heinemann, K. Dissauer, C. Scolini, E. Asvestari, A. M. Veronig, S. J. Hofmeister   +10 more
wiley   +1 more source

The Subaru coronagraphic extreme AO (SCExAO) system: Visible imaging mode [PDF]

, 2020
The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system is an instrument designed to be inserted between the Subaru AO188 system and the infrared HiCIAO camera in order to greatly improve the contrast in the very close (less than 0.5 ...
Martinache, Frantz, Baudoz, Pierre, Kaito, Yokochi, Garrel, Vincent, Cantalloube, Faustine, Guyon, Olivier, Vogt, Frédéric P.A., Takashi, Yoshikawa   +7 more
core   +1 more source

Performance of the near-infrared coronagraphic imager on Gemini-South [PDF]

SPIE Proceedings, 2008
We present the coronagraphic and adaptive optics performance of the Gemini-South Near-Infrared Coronagraphic Imager (NICI). NICI includes a dual-channel imager for simultaneous spectral difference imaging, a dedicated 85-element curvature adaptive optics system, and a built-in Lyot coronagraph.
Chun, Mark, Toomey, Doug, Wahhaj, Zahed, Biller, Beth, Artigau, Etienne, Hayward, Tom, Liu, Mike, Close, Laird, Hartung, Markus, Rigaut, Francois, Ftaclas, Christ   +10 more
openaire   +2 more sources

Rectangular-Mask Coronagraphs for High-Contrast Imaging [PDF]

The Astrophysical Journal, 2004
We present yet another new family of masks for high-contrast imaging as required for the to-be-built terrestrial planet finder space telescope. The ``best'' design involves a square entrance pupil having a 4-vane spider, a square image-plane mask containing a plus-sign shaped occulter to block the starlight inside 0.6 lambda/D, and a Lyot-plane mask ...
Vanderbei, Robert J., Kasdin, N. Jeremy, Spergel, David N.   +2 more
openaire   +3 more sources

Square Root Compression and Noise Effects in Digitally Transformed Images

The Astrophysical Journal, 2022
We report on a particular example of noise and data representation interacting to introduce systematic error into scientific measurements. Many instruments collect integer digitized values and apply nonlinear coding, in particular square root coding, to ...
Craig E. DeForest, Chris Lowder, Daniel B. Seaton, Matthew J. West   +3 more
doaj   +1 more source

Space Weather Monitor at the L5 Point: A Case Study of a CME Observed with STEREO B

Space Weather, Volume 18, Issue 10, October 2020., 2020
Abstract An important location for future space weather monitoring is the Lagrange point 5 (L5) of the Sun‐Earth system. We test the performance of L5 for space weather monitoring using STEREO B observations of an Earth‐directed coronal mass ejection (CME), seen as a partial halo by SOHO at L1.
L. Rodriguez, C. Scolini, M. Mierla, A. N. Zhukov, M. J. West   +4 more
wiley   +1 more source

PROSWIFT Bill and the 2020 Space Weather Operations and Research Infrastructure Workshop From the National Academies of Sciences, Engineering, and Medicine

Space Weather, Volume 18, Issue 10, October 2020., 2020
Abstract The Space Weather Research and Forecasting Act (PROSWIFT) passed the U.S. Senate in July 2020 and the House of Representative on 16 September; it directs NOAA to capture remote images of coronal mass ejections (CMEs) with the Space Weather Follow‐On at L1 (SWFO‐L1) mission.
Noé Lugaz
wiley   +1 more source

High-contrast imaging results with the vortex coronagraph [PDF]

SPIE Proceedings, 2013
The vortex coronagraph has already enabled high-contrast observations very close to bright stars on large ground-based telescopes, and it also has great potential for use on coronagraphic space missions aimed at exoplanet detection and characterization.
Serabyn, E., Trauger, J., Moody, D., Mawet, D., Liewer, K., Krist, J., Kern, B.   +6 more
openaire   +2 more sources

Subaru AO Coronagraphic and Direct Imaging of YSOs [PDF]

Symposium - International Astronomical Union, 2004
A cold near-infrared stellar coronagraph combined with adaptive optics (CIAO) is introduced. As an open-use instrument on the Subaru 8.2-m telescope, it has been used for several star formation studies with high spatial resolutions (from natural seeing of about 0.6 arcsec down to 0.07 arcsec with adaptive optics).
Motohide Tamura, Misato Fukagawa, Masahiko Hayashi   +2 more
openaire   +1 more source

Wavefront Sensing by a Common-Path Interferometer for Wavefront Correction in Phase and Amplitude by a Liquid Crystal Spatial Light Modulator Aiming the Exoplanet Direct Imaging

Photonics, 2023
We implemented the common-path achromatic interfero-coronagraph both for the wavefront sensing and the on-axis image component suppression, aiming for the stellar coronagraphy.
Andrey Yudaev, Alexander Kiselev, Inna Shashkova, Alexander Tavrov, Alexander Lipatov, Oleg Korablev   +5 more
doaj   +1 more source