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We numerically study a method to increase the photon return flux of continuous-wave laser guide stars using one-dimensional atomic cooling principles. The method relies on chirping the laser towards higher frequencies following the change…

Instrumentation and Methods for Astrophysics · Physics 2020-01-10 F. Pedreros Bustos , R. Holzlöhner , S. Rochester , D. Bonaccini Calia , J. Hellemeier , D. Budker

The role of laser frequency chirps in the laser wakefield accelerator is examined. We show that in the linear regime, the evolution of the laser pulse length is affected by the frequency chirp, and that positive (negative) chirp compresses…

Plasma Physics · Physics 2015-06-03 V. B. Pathak , J. Vieira , R. A. Fonseca , L. O. Silva

Recently various laser-chirping schemes have been investigated with the goal of reducing or eliminating ponderomotive line broadening in Compton or Thomson scattering occurring at high laser intensities. As a next level of detail in the…

Accelerator Physics · Physics 2016-05-25 Balša Terzić , Cody Reeves , Geoffrey A. Krafft

We study the effect of the chirped laser pulse on the transmission and associated ion acceleration by the sub-wavelength target. In the chirped laser pulses, the pulse frequency has a temporal variation about its fundamental frequency,…

Plasma Physics · Physics 2018-11-06 Shivani Choudhary , Amol R. Holkundkar

We present a new paradigm for computation of radiation spectra in the non-linear regime of operation of inverse Compton sources characterized by high laser intensities. The resulting simulations show an unprecedented level of agreement with…

Context: Sodium laser guide stars (LGS) are about to enter a new range of laser powers. Previous theoretical and numerical methods are inadequate for accurate computations of the return flux and hence for the design of the next-generation…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 R. Holzlohner , S. M. Rochester , D. Bonaccini Calia , D. Budker , J. M. Higbie , W. Hackenberg

The first time simultaneous measurements of sodium column density and the absolute flux from a sodium laser guide star, created by a monochromatic 3 W cw laser, tuned to the peak of the sodium D2 hyperfine structure, were conducted at the…

The performance of adaptive optics systems employing sodium laser guide stars can be improved by continuously monitoring the vertical density structure of mesospheric sodium along the line of sight. We demonstrate that sodium density…

Instrumentation and Methods for Astrophysics · Physics 2020-04-01 Joschua A. Hellemeier , Domenico Bonaccini Calia , Paul Hickson , Angel Otarola , Thomas Pfrommer

Using frequency-chirped radiation pressure slowing, we precisely control the velocity of a pulsed CaF molecular beam down to a few m/s, compressing its velocity spread by a factor of 10 while retaining high intensity: at a velocity of…

Atomic Physics · Physics 2017-04-05 S. Truppe , H. J. Williams , N. J. Fitch , M. Hambach , T. E. Wall , E. A. Hinds , B. E. Sauer , M. R. Tarbutt

Detailed knowledge of the mesopheric sodium layer characteristics is crucial to estimate and optimize the performance of Laser Guide Star (LGS) assisted Adaptive Optics (AO) systems. In this paper, we present an analysis of two sets of data…

Instrumentation and Methods for Astrophysics · Physics 2013-01-17 Benoit Neichel , Celine D'Orgeville , Joseph Callingham , Francois Rigaut , Claudia Winge , Gelys Trancho

The prospects of superradiant lasing on the 7.5 kHz wide $^1$S$_0$-$^3$P$_1$ transition in $^{88}$Sr is explored by using numerical simulations of two systems based on realistic experimental numbers. One system uses the idea of…

Atomic Physics · Physics 2022-12-21 Mikkel Tang , Stefan A. Schäffer , Jörg H. Müller

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

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

Over the last few years increasing consideration has been given to the study of Laser Guide Stars (LGS) for the measurement of the disturbance introduced by the atmosphere in optical and near-infrared astronomical observations from the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 L. Schreiber , I. Foppiani , C. Robert , E. Diolaiti , J. -M. Conan , M. Lombini

Advances in high-resolution laser spectroscopy have enabled many scientific breakthroughs in physics, chemistry, biology and astronomy. Optical frequency combs have pushed measurement limits with ultrahigh-frequency accuracy and…

Optics · Physics 2023-03-27 Shuangyou Zhang , Toby Bi , Pascal Del'Haye

We present a theoretical study of how linear chirp controls plasma density in a water jet using a two-stage framework. Stage I solves carrier-population and current equations at a single point, driven by a chirped super-Gaussian pulse. By…

We are developing the Laser Guide Star Adaptive Optics (LGS/AO188) system for the Subaru Telescope at Mauna Kea, Hawaii. This system utilizes a combination of an all-solid-state mode-locked sum-frequency generation (SFG) laser (1.7-GHz…

Instrumentation and Methods for Astrophysics · Physics 2012-02-29 Meguru Ito , Yutaka Hayano , Yoshihiko Saito , Hideki Takami , Norihito Saito , Kazuyuki Akagawa , Masanori Iye

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

Large telescope's adaptive optics (AO) system requires one or several bright artificial laser guide stars to improve its sky coverage. The recent advent of high power sodium laser is perfect for such application. However, besides the output…

Instrumentation and Methods for Astrophysics · Physics 2016-05-23 Feng Lu , Zhi-Xia Shen , Suijian Xue , Yang-Peng Li , Kai Jin , Angel Otarola , Yong Bo , Jun-Wei Zuo , Qi Bian , Kai Wei , Jing-Yao Hu

We present a simple and direct method for measuring laser chirp rate, i.e., group delay dispersion (GDD) of ultrashort laser pulses at power levels compatible with single-quantum-emitter excitation. Traditional pulse characterization…

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