English
Related papers

Related papers: Beam Patterns of the Five-hundred-metre Aperture S…

200 papers

The performance of telescope systems working at microwave or visible/IR wavelengths is typically described in terms of different parameters according to the wavelength range. Most commercial ray tracing packages have been specifically…

Optics · Physics 2009-11-13 Luca Olmi , Pietro Bolli

In fiber-based spectroscopy within telescopes, a prevailing limitation has been the necessity to align the fiber diameter with the telescope's seeing conditions, often characterized by the Full Width at Half Maximum of the point spread…

Instrumentation and Methods for Astrophysics · Physics 2024-06-25 Nitish Singh , S. Sriram , Bharat Kumar Yerra , Prasanna G. Deshmukh

The active reflector is one of the three main innovations of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The deformation of such a huge spherically shaped reflector into different transient parabolic shapes is achieved…

Instrumentation and Methods for Astrophysics · Physics 2018-02-08 Hai-Yan Zhang , Ming-Chang Wu , You-Ling Yue , Heng-Qian Gan , Hao Hu , Shi-Jie Huang

Based on the background of the 2021 Higher Education Club Cup National College Students Mathematical Contest in Modeling A, according to the relevant data of the China Sky Eye (FAST) radio telescope, the main cable nodes and actuators are…

Optimization and Control · Mathematics 2022-04-13 Tongyue Shi , Siyu Tao , Haining Wang

To explore capabilities of moderate-size optical telescopes in surveys, the set of 9 new wide-field designs having apertures up to 1 m is considered. All but one systems have angular field of view in a range 3.5-10 degrees and flat focal…

Instrumentation and Methods for Astrophysics · Physics 2016-10-26 V. Yu. Terebizh

Remote focusing (RF) is a technique that greatly extends the aberration-free axial scan range of an optical microscope. To maximise the diffraction limited depth range in an RF system, the magnification of the relay lenses should be such…

Optics · Physics 2021-01-05 Sharika Mohanan , Alexander D. Corbett

Interferometers require accurate determination of the array configuration in order to produce reliable observations. A method is presented for finding the maximum-likelihood estimate of the telescope geometry, and of other instrumental…

Astrophysics · Physics 2009-11-07 Klaus Maisinger , M. P. Hobson , Richard D. E. Saunders , Keith J. B. Grainge

We propose a sampling scheme on the sphere and develop a corresponding spherical harmonic transform (SHT) for the accurate reconstruction of the diffusion signal in diffusion magnetic resonance imaging (dMRI). By exploiting the antipodal…

Medical Physics · Physics 2015-02-26 Alice P. Bates , Zubair Khalid , Rodney A. Kennedy

We have developed an analytic model for generic image transfer using microlens-coupled fibers to determine the telescope input beam speed that optimizes the lenslet clear aperture and minimizes fiber focal-ratio degradation. Assuming fibers…

Instrumentation and Methods for Astrophysics · Physics 2020-12-29 Sabyasachi Chattopadhyay , Matthew A. Bershady , Marsha J. Wolf , andMichael P. Smith

We present the results of a programme of scanning and mapping observations of astronomical masers and Jupiter designed to characterise the performance of the Mopra Radio Telescope at frequencies between 16-50 GHz using the 12-mm and 7-mm…

After proposing a new method of deriving the atmospheric time constant from the speed of focus variations (Kellerer & Tokovinin 2007), we now implement it with the new instrument, FADE. FADE uses a 36-cm Celestron telescope that is modified…

Astrophysics · Physics 2009-11-13 A. Tokovinin , A. Kellerer , V. Coude Du Foresto

Small aperture telescopes provide the opportunity to conduct high frequency, targeted observations of near-Earth Asteroids that are not feasible with larger facilities due to highly competitive time allocation requirements. Observations of…

Earth and Planetary Astrophysics · Physics 2021-07-30 Samuel L. Jackson , Ulrich C. Kolb , Simon F. Green

An all-spherical catadioptic telescope with the angular field of view of several tens of degrees in diameter and spherical focal surface is proposed for the monitoring of large sky areas. We provide a few examples of such a system with the…

Instrumentation and Methods for Astrophysics · Physics 2016-07-20 V. Yu. Terebizh

Optical stellar interferometers have demonstrated milli-arcsecond resolution with few apertures spaced hundreds of meters apart. To obtain rich direct images, many apertures will be needed, for a better sampling of the incoming wavefront.…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha , Antoine Labeyrie

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen

We have used an Imaging Fabry-Perot Spectrophotometer with the Adaptive Optics Bonnette on the Canada-France-Hawaii Telescope to measure stellar radial velocities in the globular cluster M15. An average seeing of 0.15" full-width at half…

Astrophysics · Physics 2009-10-31 Karl Gebhardt , Carlton Pryor , R. D. O'Connell , T. B. Williams , James E. Hesser

Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Jonathan Landon , Michael Elmer , Jacob Waldron , David Jones , Alan Stemmons , Brian D. Jeffs , Karl F. Warnick , J. Richard Fisher , Roger D. Norrod

A telescope specifically designed for the observation of the stellar aberration of light is proposed. It is distinctive in two main features: a lengthy collimated beam and an adjustable position of the photo-detector along the telescope…

General Physics · Physics 2007-05-23 G. Sardin

The interplay between large antenna apertures and high carrier frequencies in future wireless systems gives rise to near-field communications, where the curvature of spherical wavefronts renders traditional far-field beamforming models…

Signal Processing · Electrical Eng. & Systems 2025-12-02 Panagiotis Gavriilidis , George C. Alexandropoulos

A major challenge in Atomic Force Microscopy (AFM) is to reduce the scan duration while retaining the image quality. Conventionally, the scan rate is restricted to a sufficiently small value in order to ensure a desirable image quality as…

Signal Processing · Electrical Eng. & Systems 2019-02-13 Kaixiang Wang , Michael G. Ruppert , Chris Manzie , Dragan Nesic , Yuen K. Yong