English
Related papers

Related papers: Sky subtraction at the Poisson limit with fibre-op…

200 papers

Given the basic parameters of a cosmic shear weak lensing survey, how well can systematic errors due to anisotropy in the point spread function (PSF) be corrected? The largest source of error in this correction to date has been the…

Astrophysics · Physics 2009-11-13 Bhuvnesh Jain , Mike Jarvis , Gary Bernstein

Context. Most popular algorithms in use to remove the effects of a telescope's point spread function (PSF) in radio astronomy are variants of the CLEAN algorithm. Most of these algorithms model the sky brightness using the delta-function…

Instrumentation and Methods for Astrophysics · Physics 2017-12-18 L. Zhang , S. Bhatnagar , U. Rau , M. Zhang

Multi-object astronomical adaptive-optics (MOAO) is now a mature wide-field observation mode to enlarge the adaptive-optics-corrected field in a few specific locations over tens of arc-minutes. The work-scope provided by open-loop…

Instrumentation and Methods for Astrophysics · Physics 2023-07-19 Carlos M. Correia , Kate Jackson , Jean-Pierre Veran , David Andersen , Olivier Lardiere , Colin Bradley

The signal of continuous gravitational waves has a longer duration than the observation period. Even if the waveform in the source frame is monochromatic, we will observe the waveform with modulated frequencies due to the motion of the…

General Relativity and Quantum Cosmology · Physics 2021-05-05 Takahiro S. Yamamoto , Takahiro Tanaka

Radio-astronomical observations are increasingly contaminated by interference, and suppression techniques become essential. A powerful candidate for interference mitigation is adaptive spatial filtering. We study the effect of spatial…

Astrophysics · Physics 2014-10-13 Amir Leshem , Alle-Jan van der Veen

Most contributions on Few-Shot Object Detection (FSOD) evaluate their methods on natural images only, yet the transferability of the announced performance is not guaranteed for applications on other kinds of images. We demonstrate this with…

Computer Vision and Pattern Recognition · Computer Science 2023-10-17 Pierre Le Jeune

Dimension-reduction techniques can greatly improve statistical inference in astronomy. A standard approach is to use Principal Components Analysis (PCA). In this work we apply a recently-developed technique, diffusion maps, to astronomical…

Astrophysics · Physics 2011-02-11 Joseph W. Richards , Peter E. Freeman , Ann B. Lee , Chad M. Schafer

We consider the problem of estimating cross-spectral quantities in the low-frequency regime, where long observation times limit averaging over large ensembles of periodograms, thereby preventing the use of approximate Gaussian statistics.…

Instrumentation and Methods for Astrophysics · Physics 2026-04-16 Lorenzo Sala , Stefano Vitale

Interferometry of the cosmic 21-cm signal is set to revolutionise our understanding of the Epoch of Reionisation (EoR) and the Cosmic Dawn (CD). The culmination of ongoing efforts will be the upcoming Square Kilometre Array (SKA), which…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Bradley Greig , Andrei Mesinger , Léon V. E. Koopmans

The wavelength dependence of atmospheric refraction causes elongation of finite-bandwidth images along the elevation vector, which produces spurious signals in weak gravitational lensing shear measurements unless this atmospheric dispersion…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Andrés A. Plazas , Gary M. Bernstein

(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

A multi-object spectrograph on the forthcoming European Extremely Large Telescope will be required to operate with good sky coverage. Many of the interesting deep cosmological fields were deliberately chosen to be free of bright foreground…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Alastair Basden , Chris Evans , Tim Morris

We present a statistical algorithm for predicting the [CII] emission from Herschel and Spitzer continuum images using probability density functions between the [CII] emission and continuum emission. The [CII] emission at 158 $\mu$m is a…

Astrophysics of Galaxies · Physics 2023-08-23 Young Min Seo , Karen Willacy , Umaa Rebbapragada

Achieving sub-arcsecond co-registration across varying time-lines of multi-wavelength and instrument images is not trivial, and requires accurate characterization of instrument pointing jitter. In this work we have investigated internal…

Solar and Stellar Astrophysics · Physics 2015-01-22 N. Brice Orange , Hakeem M. Oluseyi , David L. Chesny , Maulik Patel , Patrick Champey , Katie Hesterly , Dylan Anthony , Robert Treen

The single sideband (SSB) framework of analytical electron ptychography can account for the presence of residual geometrical aberrations induced by the probe-forming lens. However, the accuracy of this aberration correction method is highly…

[Abridged] We previously presented evidence for a varying fine-structure constant, alpha, in two independent samples of Keck/HIRES QSO spectra. Here we present a detailed many-multiplet analysis of a third Keck/HIRES sample containing 78…

Astrophysics · Physics 2009-08-18 M. T. Murphy , J. K. Webb , V. V. Flambaum

Few-Shot Object Detection (FSOD) methods are mainly designed and evaluated on natural image datasets such as Pascal VOC and MS COCO. However, it is not clear whether the best methods for natural images are also the best for aerial images.…

Computer Vision and Pattern Recognition · Computer Science 2022-10-26 Pierre Le Jeune , Anissa Mokraoui

The sensitivity of LISA depends on the suppression of several noise sources; dominant one is laser frequency noise. It has been shown that the six Doppler data streams obtained from three space-crafts can be appropriately time delayed and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. Pai , K. Rajesh Nayak , S. V. Dhurandhar , J-Y. Vinet

The advent of a new generation of low frequency interferometers has opened a direct window into the Epoch of Reionisation (EoR). However, key to a detection of the faint 21-cm signal, and reaching the sensitivity limits of these arrays, is…

Instrumentation and Methods for Astrophysics · Physics 2018-12-05 Ronniy C. Joseph , Cathryn M. Trott , Randall B. Wayth

The {\it assumption of additive absorptivity} by different components in compound particles is a widely used method applied in the literature to the analysis of the chemical and structural properties of astronomical (circumstellar,…

Astrophysics · Physics 2009-11-07 Aigen Li , J. Mayo Greenberg , Gang Zhao
‹ Prev 1 3 4 5 6 7 10 Next ›