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Preliminary site testing datasets suggest that Dome C in Antarctica is one of the best sites on Earth for astronomical observations in the 200 to 500 micron regime, i.e. for far-infrared (FIR) and submillimetre (submm) astronomy. We present…

FRAM - F/(Ph)otometric Robotic Atmospheric Monitor is the latest addition to the atmospheric monitoring instruments of the Pierre Auger Observatory. An optical telescope equipped with CCD camera and photometer, it automatically observes a…

Fourier transform (FT) spectroscopy is a versatile technique for studying the infrared (IR) optical response of solid-, liquid-, and gas-phase samples. In standard FT-IR spectrometers, a light beam passing through a Michelson interferometer…

Applied Physics · Physics 2021-03-12 Takashi Kuroda , Siti Chalimah , Yuanzhao Yao , Naoki Ikeda , Yoshimasa Sugimoto , Kazuaki Sakoda

Cherenkov telescopes image the Cherenkov emission from air showers. A priori, it is not obvious if the `best' images are achieved by measuring Cherenkov photon angles, i.e. focusing the telescope at infinity, or by considering the air…

Astrophysics · Physics 2008-11-26 Werner Hofmann

The Photonic Force Microscope (PFM) is an opto-mechanical technique based on an optical trap that can be assumed to probe forces in microscopic systems. This technique has been used to measure forces in the range of pico- and femto-Newton,…

Data Analysis, Statistics and Probability · Physics 2011-11-10 Giorgio Volpe , Giovanni Volpe , Dmitri Petrov

In this paper, we describe the principle of a multi-aperture interferometer that uses a phase-shifting technique and is suitable for quick, snapshot imaging of astrophysical objects at extreme angular resolution through Fourier inversion. A…

Optics · Physics 2015-05-28 Francois Henault

Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…

Optics · Physics 2025-12-16 S. A. Wadood , Shaurya Aarav , Kevin Liang , Jason W Fleischer

Due to the importance of accurate Fourier parameters, we devise a method that is more appropriate for deriving these parameters on low-quality data than the traditional Fourier fitting. Based on the accurate light curves of 248 fundamental…

Astrophysics · Physics 2009-11-11 G. Kovacs , G. Kupi

In this paper we offer a complete methodology for sufficient dimension reduction called the test function (TF). TF provides a new family of methods for the estimation of the central subspace (CS) based on the introduction of a nonlinear…

Statistics Theory · Mathematics 2011-06-08 François Portier , Bernard Delyon

In measuring the power spectrum of the distribution of large numbers of dark matter particles in simulations, or galaxies in observations, one has to use Fast Fourier Transforms (FFT) for calculational efficiency. However, because of the…

Astrophysics · Physics 2009-11-13 Weiguang Cui , Lei Liu , Xiaohu Yang , Yu Wang , Longlong Feng , Volker Springel

An important aspect of the calibration of the Cherenkov Telescope Array is the pointing, which enables an exact alignment of each telescope and therefore allows to transform a position in the sky to a point in the plane of the Cherenkov…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 D. Tiziani , M. Garczarczyk , L. Oakes , U. Schwanke , C. van Eldik

Fourier ptychography (FP), as a computational imaging method, is a powerful tool to improve imaging resolution. Camera-scanning Fourier ptychography extends the application of FP from micro to macro creatively. Due to the non-ideal scanning…

Image and Video Processing · Electrical Eng. & Systems 2022-06-08 Baiqi Cui , Shaohui Zhang , Yechao Wang , Yao Hu , Qun Hao

Asteroseismology has been extremely successful in determining the properties of stars in different evolutionary stages with a remarkable level of precision. However, to fully exploit its potential, robust methods for estimating stellar…

Solar and Stellar Astrophysics · Physics 2015-06-11 V. Silva Aguirre , L. Casagrande , S. Basu , T. L. Campante , W. J. Chaplin , D. Huber , A. Miglio , A. M. Serenelli , KASC WG#1

Accurate weak-lensing analysis requires not only accurate measurement of galaxy shapes but also precise and unbiased measurement of galaxy redshifts. The photometric redshift technique appears as the only possibility to determine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. Jouvel , J-P. Kneib , G. Bernstein , O. Ilbert , P. Jelinsky , B. Milliard , A. Ealet , C. Schimd , T. Dahlen , S. Arnouts

We derive and showcase a novel approach to approximating Fourier transforms in higher dimensions, focusing specifically on the case of 2D radially concentrated ('ring-like') functions. We first reduce the problem to that of evaluating the…

High Energy Astrophysical Phenomena · Physics 2026-04-08 Filip Niewiński , Michael D. Johnson

Cosmological random fields are often analysed in spherical Fourier-Bessel basis. Compared to the Cartesian Fourier basis this has an advantage of properly taking into account some of the relevant physical processes (redshift-space…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-17 Lado Samushia

This paper compares the performance of two different high-precision, photometric measurement techniques for bright (<11 magnitude) stars using the small telescope systems that today's amateur astronomers typically use. One technique is…

Instrumentation and Methods for Astrophysics · Physics 2019-05-21 Gerald R. Hubbell , Barton D. Billard , Dennis M. Conti , Myron E. Wasiuta , Shannon Morgan

The luminosity function (LF) for stars is here fitted by a Schechter function and by a Gamma probability density function. The dependence of the number of stars on the distance, both in the low and high luminosity regions, requires the…

Astrophysics of Galaxies · Physics 2017-12-22 Lorenzo Zaninetti

We describe a technique for measuring focus errors in a cryogenic, wide-field, near-infrared space telescope. The measurements are made with a collimator looking through a large vacuum window, with a reflective cold filter to reduce…

Instrumentation and Methods for Astrophysics · Physics 2024-10-22 Samuel S. Condon , Stephen Padin , James Bock , Howard Hui , Phillip Korngut , Chi Nguyen , Jordan Otsby

The focal-plane camera of $\gamma$-ray telescopes frequently uses light concentrators in front of light sensors. The purpose of these concentrators is to increase the effective area of the camera as well as to reduce the stray light coming…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 J. A. Aguilar , A. Basili , V. Boccone , F. Cadoux , A. Christov , D. della Volpe , T. Montaruli , L. Platos , M. Rameez