Results 41 to 50 of about 4,967 (311)

Stable Fiber-illumination for Extremely Precise Radial Velocities with NEID

The Astronomical Journal, 2023
NEID is a high-resolution red–optical precision radial velocity (RV) spectrograph recently commissioned at the WIYN 3.5 m telescope at Kitt Peak National Observatory, Arizona, USA.
Shubham Kanodia, Andrea S. J. Lin, Emily Lubar, Samuel Halverson, Suvrath Mahadevan, Chad F. Bender, Sarah E. Logsdon, Lawrence W. Ramsey, Joe P. Ninan, Gumundur Stefánsson, Andrew Monson, Christian Schwab, Arpita Roy, Leonardo A. Paredes, Eli Golub, Jesus Higuera, Jessica Klusmeyer, William McBride, Cullen Blake, Scott A. Diddams, Fabien Grisé, Arvind F. Gupta, Fred Hearty, Michael W. McElwain, Jayadev Rajagopal, Paul Robertson, Ryan C. Terrien   +26 more
doaj   +1 more source

Room‐Temperature Skyrmionic Synapse in 2D Ferromagnet Fe3GaTe2 Operating via Collective Spin Texture Transformation

Advanced Materials, EarlyView.
We demonstrate a neuromorphic synapse in 2D Fe3GaTe2 flakes. The device operates via a current‐driven transformation from a skyrmion‐lattice to a stripe‐domain state, yielding a linear anomalous Hall resistance response with a tunable slope to enable multiply‐accumulate operations. Simulations confirm its viability in artificial neural networks.
Jixiang Huang, Tongji Zhu, PeiYu Cai, Xiaoming Ma, Zhen Wang, Ruifu Zhang, Yi Hao, Jingdi Lu, Liubing He, Jun Xu, Yuejie Zhang, Wanjun Jiang, Jing Tao, Shiming Lei, Pavel Parchinskiy, Jing Teng, Lingfei Wang, Wei Niu, Elton J.G. Santos, Xiaoqian Zhang, Peng Li   +20 more
wiley   +1 more source

Review of topo-astronomical methods for the precise orientation in archaeological sites [PDF]

, 2009
Comunicación presentada en el congreso: Cosmology across cultures; workshop held at Parque de las Ciencias, Granada, Spain, 8-12 September 2008.A review of the method and instrumentation used in the determination of topo-astronomical alignments is ...
Folgueira López, Marta, Pascual, Esther, Mejuto, Javier, Folgueira, M., Rodríguez-Caderot, Gracia, Rodríguez Caderot, Gracia   +5 more
core  

Dichroic and anti-reflective coatings for astronomical instrumentation [PDF]

, 2018
International audienceDue to the increase of astronomical projects and of their instruments, the request of large optics with higher optical performances does not stop growing.
Gianpietro Cagnoli, Sassolas, Benoît, Barthélémy-Mazot, Eléonore, Hofman, David, Julien Teillon, David Hofman, Benoît Sassolas, Laurent Pinard, Teillon, Julien, Eléonore Barthélémy-Mazot, Cagnoli, Gianpietro, Michel, Christophe, Pinard, Laurent, Christophe Michel   +13 more
core   +1 more source

Self-consistent Atmosphere Representation and Interaction in Photon Monte Carlo Simulations

The Astrophysical Journal
We present a self-consistent representation of the atmosphere and implement the interactions of light with the atmosphere using a photon Monte Carlo approach.
J. R. Peterson, G. Sembroski, A. Dutta, C. Remocaldo   +3 more
doaj   +1 more source

Astronomical observations: a guide for allied researchers

The Open Journal of Astrophysics, 2019
Observational astrophysics uses sophisticated technology to collect and measure electromagnetic and other radiation from beyond the Earth. Modern observatories produce large, complex datasets and extracting the maximum possible information from them ...
Pauline Barmby
doaj   +1 more source

Polarization Criterion in Targeted SETI Observation

The Astronomical Journal, 2023
In this paper, we propose a novel method for distinguishing extraterrestrial intelligence (ETI) signals from radio frequency interference (RFI) by leveraging polarization features.
Jian-Kang Li, Yu Chen, Bo-Lun Huang, Zhen-Zhao Tao, Xiao-Hang Luan, Xiao-Hui Sun, Tong-Jie Zhang, Vishal Gajjar   +7 more
doaj   +1 more source

Twin High-Resolution, High-Speed Imagers for the Gemini Telescopes: Instrument Description and Science Verification Results

Frontiers in Astronomy and Space Sciences, 2021
Two new imaging instruments, ‘Alopeke and Zorro, were designed, built, and commissioned at the Gemini-North and Gemini-South telescopes in 2018 and 2019, respectively. Here we describe them and present the results from over a year of operation.
Nicholas J. Scott, Steve B. Howell, Crystal L. Gnilka, Andrew W. Stephens, Ricardo Salinas, Rachel A. Matson, Elise Furlan, Elliott P. Horch, Mark E. Everett, David R. Ciardi, Dave Mills, Emmett A. Quigley   +11 more
doaj   +1 more source

When Poor Exciton Dissociation Limits Photocurrents in Organic Solar Cells: Why Low Offset Non‐Fullerene Acceptor Blends Can't Be Efficient

Advanced Materials, EarlyView.
The energetic offset between the donor and the acceptor components in organic photoactive layers is central to the tradeoff between photovoltage and photocurrent losses. This Perspective covers the most important issues surrounding this topic in non‐fullerene acceptor blends, from the difficulty of accurately determining state energies and driving ...
Dieter Neher, Manasi Pranav
wiley   +1 more source

Characterization of an Optical Transfer Function–based Phasing Technique for India’s Large Segmented Mirror Telescope

The Astronomical Journal
The upcoming 10 m class large Indian telescope is proposed to be built using segmented mirror technology. To achieve diffraction-limited image quality with a segmented mirror telescope, it is important to phase mirror segments with very high precision ...
Radhika Dharmadhikari, Padmakar Parihar
doaj   +1 more source