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The most popular method of the broad-line region size estimation in active galactic nuclei (AGN) is the reverberation mapping based on measuring the time delay between the continuum flux and the flux in the emission lines. In our work, we…

Instrumentation and Methods for Astrophysics · Physics 2020-01-29 Eugene Malygin , Roman Uklein , Elena Shablovinskaya , Aleksander Perepelitsyn , Aleksandra Grokhovskaya

Obtaining well-calibrated photometric redshift probability densities for galaxies without a spectroscopic measurement remains a challenge. Deep learning discriminative models, typically fed with multi-band galaxy images, can produce outputs…

Instrumentation and Methods for Astrophysics · Physics 2024-11-27 Qiufan Lin , Hengxin Ruan , Dominique Fouchez , Shupei Chen , Rui Li , Paulo Montero-Camacho , Nicola R. Napolitano , Yuan-Sen Ting , Wei Zhang

Noise bias is a significant source of systematic error in weak gravitational lensing measurements that must be corrected to satisfy the stringent standards of modern imaging surveys in the era of precision cosmology. This paper reviews the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-09 Xiangchong Li , Rachel Mandelbaum , The LSST Dark Energy Science Collaboration

Interferometric calibration always yields non unique solutions. It is therefore essential to remove these ambiguities before the solutions could be used in any further modeling of the sky, the instrument or propagation effects such as the…

Instrumentation and Methods for Astrophysics · Physics 2013-07-19 Sarod Yatawatta

Consumer cameras, particularly onboard smartphones and UAVs, are now commonly used as scientific instruments. However, their data processing pipelines are not optimized for quantitative radiometry and their calibration is more complex than…

Instrumentation and Detectors · Physics 2019-06-25 Olivier Burggraaff , Norbert Schmidt , Jaime Zamorano , Klaas Pauly , Sergio Pascual , Carlos Tapia , Evangelos Spyrakos , Frans Snik

The rapid increase in data on galaxy images at low and high redshift calls for re-examination of the classification schemes and for new automatic objective methods. Here we present a classification method by Artificial Neural Networks. We…

Astrophysics · Physics 2007-05-23 Ofer Lahav

We present a novel, model-independent technique for fitting the cross-component of weak lensing shear, $\gamma_\times$, along a line of sight by combining kinematic and photometric measurements of a single lensed galaxy. Rather than relying…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Christopher Hopp , David Wittman

lightcurver is a photometric pipeline for time series astronomical imaging data, designed for the semi-automatic extraction of precise light curves from small, blended targets. Such targets include, but are not limited to, lensed quasars,…

Instrumentation and Methods for Astrophysics · Physics 2024-10-18 Frédéric Dux

A new approach to estimating photometric redshifts - using Artificial Neural Networks (ANNs) - is investigated. Unlike the standard template-fitting photometric redshift technique, a large spectroscopically-identified training set is…

Astrophysics · Physics 2009-11-07 Andrew E. Firth , Ofer Lahav , Rachel S. Somerville

As of any other satellite images, LAPAN-A3/IPB multispectral images suffered from both geometric and radiometric distortions which need to be corrected. LAPAN as satellite owner has developed image preprocessing algorithm to process raw…

Image and Video Processing · Electrical Eng. & Systems 2019-01-29 Patria Rachman Hakim , A Hadi Syafrudin , Sartika Salaswati , Satriya Utama , Wahyudi Hasbi

One of the main goals of the COROT mission is to get precise photometric observations of selected bright stars in order to allow the modelling of their interior through asteroseismology. However, in order to interpret the…

Astrophysics · Physics 2009-11-11 M. Gillon , P. Magain

Photonic integrated circuits offer a compact and stable platform for generating, manipulating, and detecting light. They are instrumental for classical and quantum applications. Imperfections stemming from fabrication constraints,…

Substellar companions such as exoplanets and brown dwarfs exhibit changes in brightness arising from top-of-atmosphere inhomogeneities, providing insights into their atmospheric structure and dynamics. This variability can be measured in…

The calibration of the ICARUS photo-detection system is based on a low power laser diode at 405 nm. Laser pulses arrive to one optical switch and then are sent to 36 UHV flanges, by 20 meters long optical patches. Light is then delivered to…

Instrumentation and Detectors · Physics 2022-12-21 M. Bonesini , R. Benocci , R. Bertoni , A. Chatterjee , M. Diwan , A. Menegolli , G. Raselli , M. Rossella , A. Scarpelli , N. Suarez

Adaptive optics systems require a calibration procedure to operate, whether in closed loop or even more importantly in forward control. This calibration usually takes the form of an interaction matrix and is a measure of the response on the…

Instrumentation and Methods for Astrophysics · Physics 2021-01-15 Olivier Lai , Mark Chun , Ryan Dungee , Jessica Lu , Marcel Carbillet

A class of methods for measuring time delays between astronomical time series is introduced in the context of quasar reverberation mapping, which is based on measures of randomness or complexity of the data. Several distinct statistical…

Instrumentation and Methods for Astrophysics · Physics 2017-08-16 Doron Chelouche , Francisco Pozo Nuñez , Shay Zucker

The Nancy Grace Roman Space Telescope will implement a devoted weak gravitational lensing program with its High Latitude Wide Area Survey. For cosmological purposes, a critical step in Roman image processing is to combine dithered…

Instrumentation and Methods for Astrophysics · Physics 2025-12-09 Kaili Cao , Christopher M. Hirata , Katherine Laliotis , Masaya Yamamoto , Emily Macbeth , M. A. Troxel

Following on from the second release of calibrated photometry from IPHAS, the INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane, we present incompleteness-corrected stellar density maps in the r and i photometric bands.…

Astrophysics of Galaxies · Physics 2016-01-27 H. J. Farnhill , J. E. Drew , G. Barentsen , E. A. González-Solares

The data from ground based gravitational-wave detectors such as Advanced LIGO and Virgo must be calibrated to convert the digital output of photodetectors into a relative displacement of the test masses in the detectors, producing the…

General Relativity and Quantum Cosmology · Physics 2021-03-24 Salvatore Vitale , Carl-Johan Haster , Ling Sun , Ben Farr , Evan Goetz , Jeff Kissel , Craig Cahillane

We present the results of a high-cadence spectroscopic and imaging monitoring campaign of the active galactic nucleus (AGN) of NGC 4395. High signal-to-noise-ratio spectra were obtained at the Gemini-N 8 m telescope using the GMOS integral…