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Related papers: Beam squint and Stokes V with off-axis feeds

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We report the results of a simulation and reconstruction of observations of a young stellar object (YSO) jet with the LINC-NIRVANA (LN) interferometric instrument, which will be mounted on the Large Binocular Telescope (LBT). This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Andrea La Camera , Simone Antoniucci , Mario Bertero , Patrizia Boccacci , Dario Lorenzetti , Brunella Nisini

Manifestations of orbital angular momentum induced effects in the diffraction of a radially polarized vector beam by an off-axis tilted aperture are studied both experimentally and theoretically. Experiments were carried out to extract the…

Optically focusing and imaging through strongly scattering media are challenging tasks but have widespread applications from scientific research to biomedical applications and daily life. Benefiting from the memory effect (ME) for speckle…

Optics · Physics 2021-09-17 Sujit Kumar Sahoo , Dongliang Tang , Cuong Dang

Coronagraphic imaging of exoplanets using ground-based instruments on large telescopes is intrinsically limited by speckles induced by uncorrected aberrations. These aberrations originate from the imperfect correction of the atmosphere by…

Instrumentation and Methods for Astrophysics · Physics 2022-05-04 A. Vigan , K. Dohlen , M. N'Diaye , F. Cantalloube , J. Girard , J. Milli , J. -F. Sauvage , Z. Wahhaj , G. Zins , J. -L. Beuzit , A. Caillat , A. Costille , J. Le Merrer , D. Mouillet , S. Tourenq

In astronomy or biological imaging, refractive index inhomogeneities of e.g. atmosphere or tissues induce optical aberrations which degrade the desired information hidden behind the medium. A standard approach consists in measuring these…

Optics · Physics 2023-06-01 Tengfei Wu , Marc Guillon , Gilles Tessier , Pascal Berto

We present a new method of removing PSF artifacts and improving the resolution of multidimensional data sources including imagers and spectrographs. Rather than deconvolution, which is translationally invariant, this method is based on…

We describe techniques concerning wavelength calibration and sky subtraction to maximise the scientific utility of data from tunable filter instruments. While we specifically address data from the Optical System for Imaging and low…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Tim Weinzirl , Alfonso Aragon-Salamanca , Steven P. Bamford , Bruno Rodriguez del Pino , Meghan E. Gray , Ana L. Chies-Santos

The paper proposes a method of finding the beam loss locations in a linac. If the beam is scraped at an aperture limitation, moving its centroid with two dipole correctors located upstream and oscillating in sync produces a line at the…

Accelerator Physics · Physics 2019-05-02 Alexander Shemyakin

Telescope slew and settle time markedly reduces the efficiency of wide-field multi-epoch surveys for sensitive interferometers with small fields of view. The overheads can be mitigated through the use of On-the-Fly Mosaicing (OTFM), where…

Instrumentation and Methods for Astrophysics · Physics 2019-01-16 K. P. Mooley , S. T. Myers , D. A. Frail , G. Hallinan , B. Butler , A. Kimball , K. Golap

Second-generation exoplanet imagers using extreme adaptive optics and coronagraphy have demonstrated their great potential for studying close circumstellar environments and for detecting new companions and helping to understand their…

Instrumentation and Methods for Astrophysics · Physics 2019-08-28 A. Vigan , M. N'Diaye , K. Dohlen , J. -F. Sauvage , J. Milli , G. Zins , C. Petit , Z. Wahhaj , F. Cantalloube , A. Caillat , A. Costille , J. Le Merrer , A. Carlotti , J. -L. Beuzit , D. Mouillet

Context. For accurately measuring intensities and determining magnetic field strengths of small-scale solar (magnetic) structure, knowledge of and compensation for the point spread function is crucial. For images recorded with the Swedish…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 G. B. Scharmer , M. G. Löfdahl , T. I. M. van Werkhoven , J. de la Cruz Rodriguez

The MOST, CoRoT, and Kepler space missions led to the discovery of a large number of intriguing, and in some cases unique, objects among which are pulsating stars, stars hosting exoplanets, binaries, etc. Although the space missions deliver…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Tkachenko , T. Van Reeth , V. Tsymbal , C. Aerts , O. Kochukhov , J. Debosscher

Due to limited size and imperfect of the optical components in a spectrometer, aberration has inevitably been brought into two-dimensional multi-fiber spectrum image in LAMOST, which leads to obvious spacial variation of the point spread…

Instrumentation and Methods for Astrophysics · Physics 2020-10-28 Jiali Xu , Qian Yin , Ping Guo , Xin Zheng

(Abridged) Atmospheric dispersion and field differential refraction impose severe constraints on widefield MOS observations. Flux reduction and spectral distortions must be minimised by a careful planning of the observations -- which is…

Instrumentation and Methods for Astrophysics · Physics 2014-06-04 Rubén Sánchez-Janssen , Steffen Mieske , Fernando Selman , Paul Bristow , Peter Hammersley , Michael Hilker , Marina Rejkuba , Burkhard Wolff

Image subtraction in astronomy is a tool for transient object discovery and characterization, particularly useful in wide fields, and is well suited for moving or photometrically varying objects such as asteroids, extra-solar planets and…

Instrumentation and Methods for Astrophysics · Physics 2013-01-09 Steven Hartung

Imaging through scattering is an important, yet challenging problem. Tremendous progress has been made by exploiting the deterministic input-output "transmission matrix" for a fixed medium. However, this "one-to-one" mapping is highly…

Image and Video Processing · Electrical Eng. & Systems 2018-09-27 Yunzhe Li , Yujia Xue , Lei Tian

In this work, an efficient numerical scheme is presented for seismic blind deconvolution in a multichannel scenario. The proposed method iterate with wo steps: first, wavelet estimation across all channels and second, refinement of the…

Computational Physics · Physics 2020-10-20 Naveed Iqbal , Entao Liu , James H. McClellan , Abdullatif A. Al-Shuhail

This paper presents a method of passive non-line-of-sight (NLOS) imaging using polarization cues. A key observation is that the oblique light has a different polarimetric signal. It turns out this effect is due to the polarization axis…

Image and Video Processing · Electrical Eng. & Systems 2019-12-02 Kenichiro Tanaka , Yasuhiro Mukaigawa , Achuta Kadambi

We present the S-Band Polarization All Sky Survey (S-PASS), a survey of polarized radio emission over the southern sky at Dec~$< -1^\circ$ taken with the Parkes radio telescope at 2.3~GHz. The main aim was to observe at a frequency high…

High-resolution optical microscopy has transformed biological imaging, yet its resolution and contrast deteriorate with depth due to multiple light scattering. Conventional correction strategies typically approximate the medium as one or a…