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The advent of the laser frequency comb as the wavelength calibration unit allows us to measure the radial velocity at $cm\ s^{-1}$ precision level with high stability in long-term, which enable the possibility of the detection of…

Instrumentation and Methods for Astrophysics · Physics 2018-10-15 Zhao Fei , Zhao Gang , Liu Yujuan , Wang Liang , Wang Huijuan , Li Hongbin , Ye Huiqi , Hao Zhibo , Xiao Dong , Zhang Junbo , Kellermann Hanna , Grupp Frank

The complementary fusion of light detection and ranging (LiDAR) data and image data is a promising but challenging task for generating high-precision and high-density point clouds. This study proposes an innovative LiDAR-guided stereo…

Computer Vision and Pattern Recognition · Computer Science 2022-02-25 Yongjun Zhang , Siyuan Zou , Xinyi Liu , Xu Huang , Yi Wan , Yongxiang Yao

Observational tests of ground layer wavefront recovery have been made in open loop using a constellation of four natural guide stars at the 1.55 m Kuiper telescope in Arizona. Such tests explore the effectiveness of wide-field seeing…

Astrophysics · Physics 2011-02-11 Christoph Baranec , Michael Lloyd-Hart , N. Mark Milton

The Thirty Meter Telescope (TMT) has been designed to include an adaptive optics system and associated laser guide star (LGS) facility to correct for the image distortion due to Earth's atmospheric turbulence and achieve diffraction-limited…

Atomic Physics · Physics 2015-06-04 S. M. Rochester , A. Otarola , C. Boyer , D. Budker , B. Ellerbroek , R. Holzlöhner , L. Wang

Laser-Induced Fluorescence (LIF) spectroscopy is an essential tool for probing ion and atom velocity distribution functions (VDFs) in complex plasmas. VDFs carry information about kinetic properties of the species critical for plasma…

Plasma Physics · Physics 2024-03-19 Ivan Romadanov , Yevgeny Raitses , Andrei Smolyakov

We present a modified approach to laser optical-feedback cavity-enhanced absorption spectroscopy. The technique involves continuously scanning the length of a high-finesse cavity to periodically lock a diode laser to the cavity resonance,…

Optics · Physics 2024-09-04 Christopher A. Curwen , Mathieu Fradet , Ryan M. Briggs

In order to enhance LIDAR performance metrics such as target detection sensitivity, noise resilience and ranging accuracy, we exploit the strong temporal correlation within the photon pairs generated in continuous-wave pumped semiconductor…

We investigate the use of ultra-narrow band interference filters to enable daytime use of sodium laser guide star adaptive optics systems. Filter performance is explored using theoretical and vendor supplied filter transmission profiles, a…

Instrumentation and Methods for Astrophysics · Physics 2018-09-18 Ryan Dungee , Mark Chun , Yutaka Hayano

We analyze optical soliton propagation in the presence of weak absorption lines with much narrower linewidths as compared to the soliton spectrum width using the novel perturbation analysis technique based on an integral representation in…

Optics · Physics 2010-03-25 V. L. Kalashnikov , E. Sorokin

Optical interferometry has been successful at achieving milliarcsecond resolution on bright stars. Imaging performance can improve greatly by increasing the number of baselines, which has motivated proposals to build large (~ 100 m) optical…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Paul D. Nuñez , Antoine Labeyrie , Pierre Riaud

Laser guide stars created by Rayleigh scattering provide a reasonable means to monitor atmospheric wavefront distortions for real-time correction by adaptive optics systems. Because of the $\lambda^{-4}$ wavelength dependence of Rayleigh…

Astrophysics · Physics 2007-05-23 L. A. Thompson , S. W. Teare

Low-loss single-mode optical waveguide fabrication process in extra-white soda-lime glass is demonstrated. Waveguiding structures are formed in bulk substrates employing femtosecond laser writing technology. The combination of a slit…

Lasers can be identified by their relatively long coherence lengths using interferometry. A Mach Zehnder interferometer incorporating liquid crystal polarization modulators is demonstrated as a means of low cost, robust laser detection.…

Signal Processing · Electrical Eng. & Systems 2020-06-28 David M Benton

Adaptive optics laser guide star systems perform atmospheric correction of stellar wavefronts in two parts: stellar tip-tilt and high-spatial-order laser-correction. The requirement of a sufficiently bright guide star in the field-of-view…

Instrumentation and Methods for Astrophysics · Physics 2018-01-31 Ward S. Howard , Nicholas M. Law , Carl A. Ziegler , Christoph Baranec , Reed Riddle

Pulsed sodium laser guide stars (LGS) are useful because they allow for Rayleigh blanking and fratricide avoidance in multiple-LGS systems. Bloch-equation simulations of sodium-light interactions show that these may be able to achieve…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Rachel Rampy , Donald Gavel , Simon M. Rochester , Ronald Holzlohner

We describe results from the first astronomical adaptive optics system to use multiple laser guide stars, located at the 6.5-m MMT telescope in Arizona. Its initial operational mode, ground-layer adaptive optics (GLAO), provides uniform…

In the past few years, Chinese astronomical community is actively testing astronomical sites for several new optical/infrared ground-based telescopes. These site testing campaigns conducted were mainly focused on fundamental performances of…

Instrumentation and Methods for Astrophysics · Physics 2021-11-17 Hongyang Li , Lu Feng , Junwei Zuo , Qi Bian , Botian Sun , Suijian Xue , Zhixia Shen , Yangpeng Li , Yong Bo

Spectral hole burning reduces sodium laser guide star efficiency. Due to photon recoil, atoms that are initially resonant with the single-frequency laser get Doppler shifted out of resonance, which reduces the return flux. Frequency-chirped…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 J. Hellemeier , M. Enderlein , M. Hager , D. Bonaccini Calia , R. L. Johnson , F. Lison , M. O. Byrd , L. A. Kann , M. Centrone , P. Hickson

We demonstrated sub-wavelength (~111 nm diameter) single nanowire (NW) continuous wave (CW) lasers on silicon photonic crystal in the telecom-band with direct modulation at 10 Gb/s by optical pumping at cryogenic temperatures. To estimate…

Acquiring precise information about the mode content of a laser is critical for multiplexed optical communications, optical imaging with active wave-front control, and quantum-limited interferometric measurements. Hologram-based mode…