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Related papers: Near-field cosmology with the VLT

200 papers

The limits to the angular resolution achievable with conventional ground-based telescopes are unchanged over 70 years. Atmospheric turbulence limits image quality to typically ~1 arcsec in practice. We have developed a new concept of…

Instrumentation and Methods for Astrophysics · Physics 2016-08-25 Craig Mackay , Martin Dominik , Iain Steele

Weak gravitational lensing surveys measure the distortion of the image of distant sources due to the deflections of light rays by the fluctuations of the gravitational potential along the line of sight. Since they probe the non-linear…

Astrophysics · Physics 2009-11-13 Dipak Munshi , Patrick Valageas

Long-baseline interferometry and high-resolution spectroscopy are two examples of areas that have benefited from astrophotonics devices, but the application range is expanding to other subareas and other wavelength ranges. The VLTI has been…

Instrumentation and Methods for Astrophysics · Physics 2025-11-26 Lucas Labadie

One of the major goals of observational cosmology is to acquire empirical data that has the diagnostic power to develop the theoretical modelling of the high-redshift universe, ultimately leading to an accurate understanding of the…

Astrophysics · Physics 2007-05-23 David H. Hughes

We discuss a cryogenic, multi-object near-infrared spectrometer as a second generation instrument for the VLT. The spectrometer combines 20 to 40 independent integral eld units (IFUs), which can be positioned by a cryogenic robot over the…

Astrophysics · Physics 2009-11-07 R. Genzel , R. Hofmann , D. Tomono , N. Thatte , F. Eisenhauer , M. Lehnert , M. Tecza , R. Bender

We discuss the design, construction, and use of a new class of scanning camera that eliminates a critical limitation of standard CCD drift-scan observations. A standard scan, which involves no correction for the differential drift rates and…

Astrophysics · Physics 2009-10-28 Dennis Zaritsky , Stephen A. Shectman , Gregory Bredthauer

We have built and tested a compact, low-cost, but very-high-performance astronomical polarimeter based on a continuously rotating half-wave plate and a high-speed imaging detector. The polarimeter is suitable for small telescopes up to ~1 m…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Jeremy Bailey , Daniel V. Cotton , Ain De Horta , Lucyna Kedziora-Chudczer , Om Shastri

A new generation of interferometric instruments is emerging which aim to use intensity mapping of redshifted $21\,$cm radiation to measure the large-scale structure of the Universe at $z\simeq 1-2$ over wide areas of sky. While these…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Martin White , Nikhil Padmanabhan

Paradoxically, imaging with resolution much below the wavelength $\lambda$ - now common place in the visible spectrum - remains challenging at lower frequencies, where arguably it is needed most due to the large wavelengths used. Techniques…

Optics · Physics 2023-12-12 Alessandro Tuniz , Boris T. Kuhlmey

Images of near-field SAR contains spatial-variant sidelobes and clutter, subduing the image quality. Current image restoration methods are only suitable for small observation angle, due to their assumption of 2D spatial-invariant…

Signal Processing · Electrical Eng. & Systems 2022-10-06 Wensi Zhang , Xiaoling Zhang , Xu Zhan , Yuetonghui Xu , Jun Shi , Shunjun Wei

The success of the SWIFT/BAT and INTEGRAL missions has definitely opened a new window for follow-up and deep study of the transient gamma-ray sky. This now appears as the access key to important progresses in the area of cosmological…

In this work, we present a study of the void lensing signal or the excess surface mass density (ESMD) around cosmic voids. First, we propose a new void-finder algorithm that is designed to capture the ESMD around voids. We compare our…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-27 Renan Boschetti , Pauline Vielzeuf , Marie-Claude Cousinou , Stephanie Escoffier , Eric Jullo

We discuss experimental studies of the interaction between a nanoscopic object and a photonic crystal membrane resonator of quality factor Q=55000. By controlled actuation of a glass fiber tip in the near-field of a photonic crystal, we…

Other Condensed Matter · Physics 2009-11-13 S. Mujumdar , A. F. Koenderink , T. Suenner , B. C. Buchler , M. Kamp , A. Forchel , V. Sandoghdar

We have designed, constructed and put into operation a very large area CCD camera that covers the field of view of the 1.2 m Samuel Oschin Schmidt Telescope at the Palomar Observatory. The camera consists of 112 CCDs arranged in a mosaic of…

Camera lenses are increasingly used in wide-field astronomical surveys due to their high performance, wide field-of-view (FOV) unreachable from traditional telescope optics, and modest cost. The machining and assembly tolerances for…

Instrumentation and Methods for Astrophysics · Physics 2020-01-06 Jeffrey K. Ratzloff , Nicholas M. Law , Henry T. Corbett , Octavi Fors , Daniel del Ser

Community access to deep (i ~ 25), highly-multiplexed optical and near-infrared multi-object spectroscopy (MOS) on 8-40m telescopes would greatly improve measurements of cosmological parameters from LSST. The largest gain would come from…

The recently unveiled deep-field images from the James Webb Space Telescope have renewed interest in what we can and cannot see of the universe. Answering these questions requires understanding the so-called "cosmological horizons" and the…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Michele Re Fiorentin , Stefano Re Fiorentin

It has been proposed that an additional U(1) sector of hidden photons could account for the Dark Matter observed in the Universe. When passing through an interface of materials with different dielectric properties, hidden photons can give…

The Galactic centre and its surrounding space are important in studying galaxy-scale evolution, and stellar populations therein are expected to have imprints of the long-term evolution. Interstellar extinction, however, severely limits…

Astrophysics of Galaxies · Physics 2018-10-03 Noriyuki Matsunaga

Time-series photometry from space in the ultraviolet can be presently done with only a few platforms, none of which is able to provide wide-field long-term high-cadence photometry. We present a concept of UVSat, a twin space telescope which…

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