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A micro-pulse lidar at eye-safe wavelength is constructed based on an up-conversion single-photon detector. The ultralow noise detector enables using integration technique to improve the signal-to-noise ratio of the atmospheric…

Wind speed measurements using heterodyne lidars are limited in spatial resolution because of the current signal processing methods. This limit is equal to c $\tau$ ( c is the speed of light and $\tau$ is the laser pulse duration)…

Instrumentation and Detectors · Physics 2025-10-28 Theo Martin , Laurent Mugnier , Matthieu Valla , Pierre Etienne Allain , David Tomline Michel

For the first time, a versatile, eyesafe, compact and direct detection Doppler lidar is developed using upconversion single-photon detection method. An all-fiber and polarization maintaining architecture is realized to guarantee the high…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 Haiyun Xia , Mingjia Shangguan , Chong Wang , Guoliang Shentu , Jiawei Qiu , Qiang Zhang , Xiankang Dou , Jianwei Pan

An atmospheric transparency was measured using a LIDAR with a pulsed UV laser (355nm) at the observation site of Telescope Array in Utah, USA. The measurement at night for two years in $2007\sim 2009$ revealed that the extinction…

Atmospheric lidar observations provide a unique capability to directly observe the vertical column of cloud and aerosol scattering properties. Detector and solar background noise, however, hinder the ability of lidar systems to provide…

Optimization and Control · Mathematics 2016-06-21 Willem J. Marais , Robert E. Holz , Yu Hen Hu , Ralph E. Kuehn , Edwin E. Eloranta , Rebecca M. Willett

The atmospheric aerosol monitoring system of the Pierre Auger Observatory has been operating smoothly since 2004. Two laser facilities (Central Laser Facility, CLF and eXtreme Laser Facility, XLF) fire sets of 50 shots four times per hour…

Instrumentation and Methods for Astrophysics · Physics 2019-06-12 Laura Valore

Atmospheric aerosols have a major influence on the earths climate and public health. Hence, studying their properties and recovering them from light scattering measurements is of great importance. State of the art retrieval methods such as…

Atmospheric and Oceanic Physics · Physics 2021-11-16 Romana Boiger , Rob L. Modini , Alireza Moallemi , David Degen , Martin Gysel-Beer , Andreas Adelmann

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

An UV-VIS polarization Lidar has been designed and specified for aerosols monitoring in the troposphere, showing the ability to precisely address low particle depolarization ratios, in the range of a few percents. Non-spherical particle…

Atmospheric and Oceanic Physics · Physics 2017-08-23 G. David , A. Miffre , B. Thomas , P. Rairoux

We have developed and tested a novel method, based on LIDAR, of measuring the height and profile of the mesospheric sodium layer using a continuous wave laser. It is more efficient than classical LIDAR as the laser is on for 50% of the…

Astrophysics · Physics 2009-11-07 D. J. Butler , R. I. Davies , R. M. Redfern , N. Ageorges , H. Fews

An all-fiber, micro-pulse and eye-safe high spectral resolution wind lidar (HSRWL) at 1550nm is proposed and demonstrated by using a pair of upconversion single-photon detectors and a fiber Fabry-Perot scanning interferometer (FFP-SI). In…

Instrumentation and Methods for Astrophysics · Physics 2016-09-13 Mingjia Shangguan , Haiyun Xia , Chong Wang , Jiawei Qiu , Guoliang Shentu , Qiang Zhang , Xiankang Dou , Jian-wei Pan

Visualizing molecular transformations in real-time requires a structural retrieval method with {\AA}ngstr\"om spatial and femtosecond temporal atomic resolution. Imaging of hydrogen-containing molecules additionally requires an imaging…

We describe an experiment, located in south-east Colorado, USA, that measured aerosol optical depth profiles using two Lidar techniques. Two independent detectors measured scattered light from a vertical UV laser beam. One detector, located…

This paper discusses the multi-wavelength scanning Raman lidar being built at Lidar Division, CEILAP (CITEDEF-CONICET) in the frame of the Argentinean Cherenkov Telescope Array (CTA) collaboration to measure the spectral characteristics of…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Juan Pallotta , Pablo Ristori , Lidia Otero , Fernando Chouza , Delia Raul , Francisco Gonzalez , Alberto Etchegoyen , Eduardo Quel

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

We consider the problem of retrieving the aerosol extinction coefficient from Raman lidar measurements. This is an ill--posed inverse problem that needs regularization, and we propose to use the Expectation--Maximization (EM) algorithm to…

Near-diffraction limited imaging and spectroscopy in the visible on large (8-10 meter) class telescopes has proved to be beyond the capabilities of current adaptive optics technologies, even when using laser guide stars. The need for high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Craig Mackay , Tim D. Staley , David King , Frank Suess , Keith Weller

The highest resolution images ever taken in the visible were obtained by combining Lucky Imaging and low order adaptive optics. This paper describes a new instrument to be deployed on the WHT 4.2m and GTC 10.4 m telescopes on La Palma, with…

One important frontier for astronomical adaptive optics (AO) involves methods such as Multi-Object AO and Multi-Conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Mark Ammons , Luke Johnson , Edward A. Laag , Renate Kupke , Donald T. Gavel , Brian J. Bauman , Claire E. Max

Laser guide stars with adaptive optics allow astronomical image correction in the absence of a natural guide star. Single guide star systems with a star created in the earth's sodium layer can be used to correct the wavefront in the near…

Astrophysics · Physics 2009-11-11 S. Rabien , F. Eisenhauer , R. Genzel , R. I. Davies , T. Ott
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