Results 21 to 30 of about 4,718 (209)

Far-ultraviolet to Near-infrared Observations of SN 2023ixf: A High-energy Explosion Engulfed in Complex Circumstellar Material

The Astrophysical Journal Letters, 2023
We present early-phase panchromatic photometric and spectroscopic coverage spanning the far-ultraviolet to near-infrared regime of the nearest hydrogen-rich core-collapse supernova (SN) in the last 25 yr, SN 2023ixf.
Rishabh Singh Teja, Avinash Singh, Judhajeet Basu, G. C. Anupama, D. K. Sahu, Anirban Dutta, Vishwajeet Swain, Tatsuya Nakaoka, Utkarsh Pathak, Varun Bhalerao, Sudhanshu Barway, Harsh Kumar, Nayana A. J., Ryo Imazawa, Brajesh Kumar, Koji S. Kawabata   +15 more
doaj   +1 more source

New Water Oxidation Mechanism in Photosystem II Resolves Major Experimental Controversies

Angewandte Chemie, EarlyView.
In Photosystem II Oxygen Evolving Complex, we discovered the O3‐O6 peroxide at lower energy. Assignment of the O3 ligated by histidine (His337) as a slow exchanging substrate and its coupling with O6 give the O─O bond formation mechanism most consistent with all currently available experimental data. Proposal shows how protein environment can steer the
Yulia Pushkar
wiley   +2 more sources

Molecular Outgassing in Centaur 29P/Schwassmann–Wachmann 1 during Its Exceptional 2021 Outburst: Coordinated Multiwavelength Observations Using nFLASH at APEX and iSHELL at the NASA-IRTF

The Planetary Science Journal, 2023
The extraordinary 2021 September–October outburst of Centaur 29P/Schwassmann–Wachmann 1 afforded an opportunity to test the composition of primitive Kuiper disk material at high sensitivity.
Nathan X. Roth, Stefanie N. Milam, Michael A. DiSanti, Geronimo L. Villanueva, Sara Faggi, Boncho P. Bonev, Martin A. Cordiner, Anthony J. Remijan, Dominique Bockelée-Morvan, Nicolas Biver, Jacques Crovisier, Dariusz C. Lis, Steven B. Charnley, Emmanuel Jehin, Eva S. Wirström, Adam J. McKay   +15 more
doaj   +1 more source

Recent developments in superconducting tunnel junctions for ultraviolet, optical & near infrared astronomy [PDF]

Astronomy and Astrophysics Supplement Series, 1998
Some recent results associated with the development of tantalum based photon counting superconducting tunnel junctions (STJ) suitable for use as broad-band low resolution spectrometers for optical and ultraviolet astronomy are presented. A m square tantalum based STJ, operated at a temperature of 0.3 K, has demonstrated a limiting resolution of  nm at ...
T. Peacock, P. Verhoeve, N. Rando, C. Erd, M. Bavdaz, B. G. Taylor, D. Perez   +6 more
openaire   +1 more source

Tailoring Photochromism Beyond Human Eye Visibility: On/Off Switchable NIR Absorption in an Aluminosilicate

Angewandte Chemie, EarlyView.
A new photochromic material was developed. Its on/off‐switchable absorption band is situated completely outside the human eye's visibility, in the near‐infrared (NIR) region, a feature never reported before. The photochromism mechanism in this aluminosilicate is elucidated by combining experimental as well as computational results, and the material's ...
Bettiina Muurinen, Hannah Byron, Teppo Kreivilä, Roosa Vastamäki, Sami Vuori, Tomasz Galica, Ian P. Machado, Sari Granroth, Basit Ali, Maarit Karppinen, Ivo Heinmaa, Milica Todorović, Raphael Rullan, Stephan Steinmann, Tangui Le Bahers, Mika Lastusaari   +15 more
wiley   +2 more sources

Development of a Monitoring System for an Infrared Camera [PDF]

Journal of Astronomy and Space Sciences, 2006
The KASINICS (KASI Near-Infrared Camera System) is a ground-based instrument developed by the Korea Astronomy and Space Science Institute (KASI). We developed a temperature and vacuum monitoring system for operating the KASINICS.
Sang-Mok Cha, Bongkon Moon, Ho Jin, In-Soo Yuk, Uk-Won Nam, Sungho Lee, Yungsik Park, Seounghyun Cho, Seungwon Mok, Chun-Hwey Kim   +9 more
doaj   +1 more source

Alignment of the grating wheel mechanism for a ground-based cryogenic near-infrared astronomy instrument [PDF]

SPIE Proceedings, 2003
We describe the population, optomechanical alignment, and alignment verification of near-infrared gratings on the grating wheel mechanism (GWM) for the Infrared Multi-Object Spectrometer (IRMOS). IRMOS is a cryogenic (80 K), principle investigator-class instrument for the 2.1 m and Mayall 3.8 m telescopes at Kitt Peak National Observatory, and a MEMS ...
Sharon M. Gutkowski, Raymond G. Ohl, Jason E. Hylan, John G. Hagopian, Stephen E. Kraft, J. E. Mentzell, Joseph A. Connelly, Joseph P. Schepis, Leroy M. Sparr, Matthew A. Greenhouse, John W. MacKenty   +10 more
openaire   +1 more source

The Mauna Kea Observatories Near‐Infrared Filter Set. II. Specifications for a NewJHKL′M′ Filter Set for Infrared Astronomy [PDF]

Publications of the Astronomical Society of the Pacific, 2002
We present a description of a new 1--5 $μ$m filter set similar to the long-used JHKLM filter set derived from that of Johnson. The new Mauna Kea Observatories Near-Infrared (MKO-NIR) filter set is designed to reduce background noise, improve photometric transformations from observatory to observatory, provide greater accuracy in extrapolating to zero ...
Tokunaga, A., Simons, D., Vacca, W.
openaire   +3 more sources

First tests of a 1 megapixel near-infrared avalanche photodiode array for ultra-low background space astronomy

X-Ray, Optical, and Infrared Detectors for Astronomy X, 2022
Spectroscopy of Earth-like exoplanets and ultra-faint galaxies are priority science cases for the coming decades. Here, broadband source flux rates are measured in photons per square meter per hour, imposing extreme demands on detector performance, including dark currents lower than 1 e-/pixel/kilosecond, read noise less than 1 e-/pixel/frame, and ...
Claveau, Charles-Antoine, Bottom, Michael, Jacobson, Shane, Hodapp, Klaus, Walk, Aidan, Loose, Markus, Baker, Ian, Zemaityte, Egle, Hicks, Matthew, Barnes, Keith, Powell, Richard, Bradley, Ryan, Moore, Eric   +12 more
openaire   +2 more sources

Photocatalytic Water Splitting on the Lunar Surface: Prospects for In Situ Resource Utilization

Advanced Materials Interfaces, EarlyView.
Water has been found in craters on the moon nearby locations which are illuminated >80% of the time. Photocatalysis uses energy from sunlight to drive chemical reactions such as water splitting to produce oxygen and hydrogen. It is a scalable technology that requires lighter equipment and utilizes resources available on the moon. ABSTRACT The discovery
Ranjani Kalyan, Thomas D. Small, Gregory F. Metha, Mahmoud Adel Hamza, Thomas J. O'Dea, Yideng Shen, Cameron J. Shearer   +6 more
wiley   +1 more source