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The Speckle Imager via MUlti Layer Atmospheric Turbulence Object Reconstructor (SIMULATOR) is a lab-based testbed instrument developed to test for speckle correlation-based techniques in the optical regime. However, this instrument can be…

Instrumentation and Methods for Astrophysics · Physics 2022-08-11 Sorabh Chhabra , Abhay A. Kohok , Bhushan S. Joshi , A. N. Ramprakash , Chaitanya V. Rajarshi , Rani S. Bhandare

We propose a simple method for the detection of Bessel beams with arbitrary radial and azimuthal indices, and then demonstrate it in an all-digital setup with a spatial light modulator. We confirm that the fidelity of the detection method…

The Simons Observatory (SO) is a new suite of cosmic microwave background telescopes in the Chilean Atacama Desert with an extensive science program spanning cosmology, Galactic and extragalactic astrophysics, and particle physics. SO will…

We consider the problem of measurement of optical transverse profile parameters and their conjugate variable. Using multi-mode analysis, we introduce the concept of detection noise-modes. For Gaussian beams, displacement and tilt are a pair…

Quantum Physics · Physics 2009-11-11 Vincent Delaubert , Nicolas Treps , Charles C. Harb , Ping Koy Lam , Hans A. Bachor

The Telescope to Observe Planetary Systems (TOPS) is a proposed space mission to image in the visible (0.4-0.9 micron) planetary systems of nearby stars simultaneously in 16 spectral bands (resolution R~20). For the ~10 most favorable…

We introduce a simple but practical method to measure the optical transmission matrix (TM) of complex media. The optical TM of a complex medium is obtained by modulating the wavefront of a beam impinging on the complex medium and imaging…

Optics · Physics 2015-06-23 Jonghee Yoon , KyeoReh Lee , Jongchan Park , YongKeun Park

Some applications in scientific imaging, like space-based high-precision photometry, benefit from a detailed characterization of the sensitivity variation within a pixel. A detailed map of the intra-pixel sensitivity (IPS) allows to…

Instrumentation and Methods for Astrophysics · Physics 2018-05-07 Swaraj Bandhu Mahato , Joris De Ridder , Guy Meynants , Gert Raskin , Hans Van Winckel

The present study extends the analysis of turbulence-affected beam statistics through a manifold-based statistical framework that unifies probabilistic modeling with geometric interpretation. The spatial intensity distributions, distorted…

Optics · Physics 2025-10-22 Shouvik Sadhukhan , C. S. Narayanamurthy

Light rays incident on a transparent object of uniform refractive index undergo deflections, which uniquely characterize the surface geometry of the object. Associated with each point on the surface is a deflection map (or spectrum) which…

Computer Vision and Pattern Recognition · Computer Science 2015-07-15 Prasad Sudhakar , Laurent Jacques , Xavier Dubois , Philippe Antoine , Luc Joannes

Current projects for large telescopes demand a proper knowledge of atmospheric turbulence to design efficient adaptive optics systems in order to reach large Strehl ratios. However, the proper characterization of the turbulence above a…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 B. Garcia-Lorenzo , A. Eff-Darwich , J. J. Fuensalida , J. Castro-Almazan

Aims. In this article we aim to show how the gradient of the thermal millimetre continuum spectrum, as emitted from the quiet solar atmosphere, may be used as a diagnostic for the optical thickness regime at the centre of the observing…

Solar and Stellar Astrophysics · Physics 2018-09-26 Andrew S. Rodger , Nicolas Labrosse

The rotational Doppler effect associated with light's orbital angular momentum (OAM) has been found as a powerful tool to detect rotating bodies. However, this method was only demonstrated experimentally on the laboratory scale under well…

A new measuring technique dedicated to bubble velocity and size measurements in complex bubbly flows such as those occurring in bubble columns is proposed. This sensor combines the phase detection capability of a conical optical fiber, with…

Fluid Dynamics · Physics 2021-09-17 Anthony Lefebvre , Yann Mezui , Martin Obligado , Stéphane Gluck , Alain Cartellier

In the stably stratified ocean, small-scale turbulence is important for vertical exchange and hence for the mixing of water masses and suspended matter. To observationally study turbulent motions and the buoyancy- and shear-generators…

Atmospheric and Oceanic Physics · Physics 2022-09-23 Hans van Haren

Particle-laden turbulence involves complex interactions between the dispersed and continuous phases. Given that particles can exhibit a wide range of properties, such as varying density, size, and shape, their interplay with the flow can…

We present a study of the small-scale structure of the interstellar medium in the Milky Way. We used HST STIS data to measure N(HI) in a pencil-beam toward 59 AGNs and compared the results with the values seen at 9 arcmin - 36 arcmin…

Astrophysics of Galaxies · Physics 2015-05-20 Bart P. Wakker , Felix J. Lockman , Jonathan M. Brown

The Las Cumbres Observatory operates a fleet of robotically controlled telescopes currently two 2m, nine 1m, and ten 0.4m telescopes, distributed amongst six sites covering both hemispheres. Telescopes of an aperture class are equipped with…

Instrumentation and Methods for Astrophysics · Physics 2018-06-01 Daniel-Rolf Harbeck , Curtis McCully , Andrew Pickles , Nikolaus Volgenau , Patrick Conway , Brook Taylor

(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

Phase referencing is a standard calibration procedure in radio interferometry. It allows to detect weak sources by using quasi-simultaneous observations of closeby sources acting as calibrators. Therefore, it is assumed that, for each…

Instrumentation and Methods for Astrophysics · Physics 2011-01-25 I. Marti-Vidal , J. C. Guirado , S. Jimenez-Monferrer , J. M. Marcaide

Many applications seek to measure a sample's absorption coefficient spectrum to retrieve the chemical makeup. Many real world samples are optically turbid, causing scattering confounds which many commercial spectrometers cannot address.…

Optics · Physics 2023-01-05 Giles Blaney , Angelo Sassaroli , Sergio Fantini
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