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Related papers: Extending the Li&Ma method to include PSF informat…

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The analysis of ring images produced by muons in an Imaging Atmospheric Cherenkov Telescope (IACT) provides a powerful and precise method to calibrate the IACT optical throughput and monitor its optical point-spread function (PSF). First…

Instrumentation and Methods for Astrophysics · Physics 2019-07-11 Markus Gaug , Steven Fegan , Alison Mitchell , Maria-Concetta Maccarone , Teresa Mineo , Akira Okumura

An improved way of taking off-source data for background determination in Cherenkov telescope observations is proposed. Generalizing the traditional concept of taking on-source/off-source observations of equal duration (e.g. 30 minutes ON…

Astrophysics · Physics 2009-11-07 Dirk Petry

Atmospheric Cherenkov telescopes rely on the Earth's atmosphere as part of the detector. The presence of clouds affects observations and can introduce biases if not corrected for. Correction methods typically require an atmospheric profile,…

Instrumentation and Methods for Astrophysics · Physics 2024-04-03 Julian Sitarek , Mario Pecimotika , Natalia Żywucka , Dorota Sobczyńska , Abelardo Moralejo , Dario Hrupec

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez

The knowledge of the exact structure of the optical system PSF enables a high-quality image reconstruction in fluorescence microscopy. Accurate PSF models account for the vector nature of light and the phase and amplitude modifications.…

We introduce a procedure to automatically count and locate the fluorescent particles in a microscopy image. Our procedure employs an approximate likelihood estimator derived from a Poisson random field model for photon emission. Estimates…

Applications · Statistics 2010-11-10 John Hughes , John Fricks , William Hancock

We present a new technique for monitoring microlensing activity even in highly crowded fields, and use this technique to place limits on low-mass MACHOs in the haloes of M31 and the Galaxy. Unlike present Galactic microlensing surveys, we…

Astrophysics · Physics 2009-09-28 Austin B. Tomaney , Arlin P. S. Crotts

In this paper we discuss the issue of loosing telemetry (TM) data due to different reasons (e.g. spacecraft-ground transmissions) while performing a full-sky survey with space-borne instrumentation. This is a particularly important issue…

Astrophysics · Physics 2009-11-07 D. Maino , C. Burigana , F. Pasian

Galaxy imaging surveys observe a vast number of objects that are affected by the instrument's Point Spread Function (PSF). Weak lensing missions, in particular, aim at measuring the shape of galaxies, and PSF effects represent an important…

Instrumentation and Methods for Astrophysics · Physics 2021-02-03 T. Liaudat , J. Bonnin , J. -L. Starck , M. A. Schmitz , A. Guinot , M. Kilbinger , S. D. J. Gwyn

You & Cheng (1980) argued that, for relativistic electrons moving through a dense gas, the Cerenkov effect will produce peculiar atomic and/or molecular emission lines--Cerenkov lines. They presented a series of formulae to describe the new…

Astrophysics · Physics 2007-05-23 J. H. You , Y. D. Xu , D. B. Liu , J. R. Shi , G. X. Jin

Novel methods for rapidly estimating single-photon source (SPS) quality have been promoted in recent literature to address the expensive and time-consuming nature of experimental validation via intensity interferometry. However, the…

It is generally assumed that fluorescence radiation does not play a significant role in the performance of Cherenkov telescopes. However, this assumption is required to be verified using detailed Monte Carlo simulations. In order to do…

Instrumentation and Methods for Astrophysics · Physics 2017-09-01 Daniel Morcuende , José Luis Contreras , Jaime Rosado , Lab Saha , Vitor de Souza

Point spread function (PSF) reconstruction (PSF-R) is a well established technique to determine reliably and accurately the PSF from Adaptive Optics (AO) control loop data. We have successfully applied this technique to improve the…

Instrumentation and Methods for Astrophysics · Physics 2020-04-15 Olivier Beltramo-Martin , Antonino Marasco , Thierry Fusco , Davide Massari , Julien Milli , Giuliana Fiorentino , B. Neichel

The imminent availability of large arrays of large light collectors deployed to exploit atmospheric Cherenkov radiation for gamma-ray astronomy at more than 100GeV, motivates the growing interest in application of intensity interferometry…

Instrumentation and Methods for Astrophysics · Physics 2009-09-30 M. Daniel , W. J. de Wit , D. Dravins , D. Kieda , S. LeBohec , P. Nunez , E. Ribak

We present the development of a data-driven, AI-based model of the Point Spread Function (PSF) that achieves higher accuracy than the current state-of-the-art approach, "PSF in the Full Field-of-View'' (PIFF). PIFF is widely used in leading…

Instrumentation and Methods for Astrophysics · Physics 2026-02-18 Dayana Andrea Henao Arbeláez , Pierre-François Léget , Andrés Alejandro Plazas Malagón

The measurement of the average depth of the shower maximum is the most commonly used observable for the possible inference of the primary cosmic-ray mass composition. Currently, different experimental Collaborations process and present…

Instrumentation and Methods for Astrophysics · Physics 2015-03-20 R. Ulrich , L. Cazon

The Cherenkov Telescopic Array (CTA), the next-generation ground-based gamma-ray observatory, will have unprecedented sensitivity, providing answers to open questions in gamma-ray cosmology and fundamental physics. Using simulations of…

Instrumentation and Methods for Astrophysics · Physics 2021-10-18 Ievgen Vovk , Jonathan Biteau , Humberto Martinez-Huerta , Manuel Meyer , Santiago Pita

Many surveys use maximum-likelihood (ML) methods to fit models when extracting photometry from images. We show these ML estimators systematically overestimate the flux as a function of the signal-to-noise ratio and the number of model…

Instrumentation and Methods for Astrophysics · Physics 2020-03-25 Stephen K. N. Portillo , Joshua S. Speagle , Douglas P. Finkbeiner

A novel application of machine-learning (ML) based image processing algorithms is proposed to analyze an all-sky map (ASM) obtained using the Fermi Gamma-ray Space Telescope. An attempt was made to simulate a one-year ASM from a…

High Energy Astrophysical Phenomena · Physics 2021-06-02 Shogo Sato , Jun Kataoka , Soichiro Ito , Jun'ichi Kotoku , Masato Taki , Asuka Oyama , Takaya Toyoda , Yuki Nakamura , Marino Yamamoto

Bayesian inference for spatial point patterns is often hindered computationally by intractable likelihoods. In the frequentist literature, estimating equations utilizing pseudolikelihoods have long been used for simulation-free parameter…

Methodology · Statistics 2025-07-24 Kevin M. Collins , Erin M. Schliep