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Related papers: GausSN: Bayesian Time-Delay Estimation for Strongl…

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We explore the effectiveness of deep learning convolutional neural networks (CNNs) for estimating strong gravitational lens mass model parameters. We have investigated a number of practicalities faced when modelling real image data, such as…

Instrumentation and Methods for Astrophysics · Physics 2019-07-24 James Pearson , Nan Li , Simon Dye

Gravitational microlensing is a unique probe of the stellar content in strong lens galaxies. Flux ratio anomalies from gravitationally lensed supernovae (glSNe), just like lensed quasars, can be used to constrain the stellar mass fractions…

Astrophysics of Galaxies · Physics 2025-04-01 Luke Weisenbach , Thomas Collett , Wolfgang Enzi , Lindsay Oldham , Ana Sainz de Murieta

We introduce a novel method for discerning optical telescope images of stars from those of galaxies using Gaussian processes (GPs). Although applications of GPs often struggle in high-dimensional data modalities such as optical image…

Instrumentation and Methods for Astrophysics · Physics 2022-03-14 Amanda L. Muyskens , Imène R. Goumiri , Benjamin W. Priest , Michael D. Schneider , Robert E. Armstrong , Jason M. Bernstein , Ryan Dana

Multiply imaged, gravitationally lensed supernovae are rare but powerful tools for providing independent measurements on cosmological parameters. Supernova (SN) 2025wny ("SN Winny") is the first gravitationally-lensed Type I superluminous…

Time-domain astronomy is entering a new era as wide-field surveys with higher cadences allow for more discoveries than ever before. The field has seen an increased use of machine learning and deep learning for automated classification of…

Instrumentation and Methods for Astrophysics · Physics 2022-12-28 Umar. F. Burhanudin , Justyn. R. Maund

We present the discovery of SN 2025wny (ZTF25abnjznp/GOTO25gtq) and spectroscopic classification of this event as the first gravitationally lensed Type I superluminous supernovae (SLSN-I). Deep ground-based follow-up observations resolves…

Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Xiao-Lei Meng , Tommaso Treu , Adriano Agnello , Matthew W. Auger , Kai Liao , Philip J. Marshall

Secure confirmation that a gravitational wave (GW) has been gravitationally lensed would bring together these two pillars of General Relativity for the first time. This breakthrough is challenging for many reasons, including: GW sky…

The quadruple quasar H1413+117 (z_s = 2.56) has been monitored with the 2.0 m Liverpool Telescope in the r Sloan band from 2008 February to July. This optical follow-up leads to accurate light curves of the four quasar images (A-D), which…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Luis J. Goicoechea , Vyacheslav N. Shalyapin

Several machine learning problems arising in natural language processing can be modeled as a sequence labeling problem. We provide Gaussian process models based on pseudo-likelihood approximation to perform sequence labeling. Gaussian…

Machine Learning · Computer Science 2016-09-22 P. K. Srijith , P. Balamurugan , Shirish Shevade

We present a statistical framework for estimating global navigation satellite system (GNSS) non-ionospheric differential time delay bias. The biases are estimated by examining differences of measured line integrated electron densities (TEC)…

Instrumentation and Methods for Astrophysics · Physics 2015-08-13 Juha Vierinen , Anthea J. Coster , William C. Rideout , Philip J. Erickson , Johannes Norberg

The cold dark matter scenario of hierarchical large-scale structure formation predicts the existence of abundant subhalos around large galaxies. However, the number of observed dwarf galaxies is far from this theoretical prediction,…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-02 Kai Liao , Xuheng Ding , Marek Biesiada , Xi-Long Fan , Zong-Hong Zhu

Microlensing not only brings extra magnification lightcurves on top of the intrinsic ones but also shifts them in time domain, making the actual time-delays between images of strongly lensed active galactic nucleus change on the $\sim$…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-06 Kai Liao

This article shortly introduces Gaussian processes (GP) as a new approach for modelling time series in the field of blazar physics. In the second part of the paper, recent results from an application of GP modelling to the multi-wavelength…

High Energy Astrophysical Phenomena · Physics 2017-03-08 V. Karamanavis

Time-delay strong lensing provides a unique way to directly measure the Hubble constant ($H_{0}$). The precision of the $H_{0}$ measurement depends on the uncertainties in the time-delay measurements, the mass distribution of the main…

Eikonal tomography has become a popular methodology for deriving phase velocity maps from surface wave phase delay measurements. Its high efficiency makes it popular for handling datasets deriving from large-N arrays, in particular in the…

Geophysics · Physics 2023-02-21 Jack B. Muir

Strong gravitational lensing of variable sources, such as quasars or supernovae, can be used to constrain cosmological parameters through a technique known as "time-delay cosmography''. Competitive constraints on the Hubble constant have…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 Simon Birrer , Graham P. Smith , Anowar J. Shajib , Dan Ryczanowski , Nikki Arendse

This paper proposes novel noise-free Bayesian optimization strategies that rely on a random exploration step to enhance the accuracy of Gaussian process surrogate models. The new algorithms retain the ease of implementation of the classical…

Machine Learning · Computer Science 2024-07-18 Hwanwoo Kim , Daniel Sanz-Alonso

We test the robustness of published time delays for 11 lensed quasars by using two techniques to measure time shifts in their light curves. We chose to use two fundamentally different techniques to determine time delays in gravitationally…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-26 Eva Eulaers , Pierre Magain

Gaussian distributions are commonly used as a key building block in many generative models. However, their applicability has not been well explored in deep networks. In this paper, we propose a novel deep generative model named as Normal…

Computer Vision and Pattern Recognition · Computer Science 2018-05-15 Jay Nandy , Wynne Hsu , Mong Li Lee