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Hybrid Foreground Residual Subtraction (HyFoReS) is a new family of algorithms designed to remove systematics-induced foreground contamination for 21-cm intensity mapping data. Previously, the algorithm was shown to be effective in…

Instrumentation and Methods for Astrophysics · Physics 2025-06-12 Haochen Wang , Panupong Phoompuang , Kiyoshi W. Masui , Arnab Chakraborty , Simon Foreman

Intelligent reflecting surface (IRS) has been widely considered as one of the key enabling techniques for future wireless communication networks owing to its ability of dynamically controlling the phase shift of reflected electromagnetic…

Signal Processing · Electrical Eng. & Systems 2022-09-02 Wenhao Cai , Ming Li , Yang Liu , Qingqing Wu , Qian Liu

The Gemini Planet Imager (GPI) is a high contrast imaging instrument that aims to detect and characterize extrasolar planets. GPI is being upgraded to GPI 2.0, with several subsystems receiving a re-design to improve the instrument's…

Low wind and petaling effects, caused by the discontinuous apertures of telescopes, are poorly corrected -- if at all -- by commonly used workhorse wavefront sensors (WFSs). Wavefront petaling breaks the coherence of the point spread…

The Keck Planet Imager and Characterizer (KPIC) is an upgrade to the Keck II adaptive optics system enabling high contrast imaging and high-resolution spectroscopic characterization of giant exoplanets in the mid-infrared (2-5 microns). The…

In this paper, we introduce an intelligent reflecting surface (IRS) to provide a programmable wireless environment for physical layer security. By adjusting the reflecting coefficients, the IRS can change the attenuation and scattering of…

Signal Processing · Electrical Eng. & Systems 2019-06-21 Jie Chen , Ying-Chang Liang , Yiyang Pei , Huayan Guo

We performed closed-loop lab testing of large-format deformable mirrors (DMs) with hybrid variable reluctance actuators. TNO has been developing the hybrid variable reluctance actuators in support for a new generation of adaptive secondary…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 Ruihan Zhang , Max Baeten , Mark R. Chun , Ellen Lee , Michael Connelley , Olivier Lai , Stefan Kuiper , Alan Ryan , Arjo Bos , Rachel Bowens-Rubin , Philip M. Hinz

This paper investigates multiuser multi-input single-output downlink symbiotic radio communication systems assisted by an intelligent reflecting surface (IRS). Different from existing methods ideally assuming the secondary user (SU) can…

Information Theory · Computer Science 2021-10-22 Shaokang Hu , Chang Liu , Zhiqiang Wei , Yuanxin Cai , Derrick Wing Kwan Ng , Jinhong Yuan

High-contrast imaging will be a challenge for future ELTs, because their vibrations create low-order aberrations - mostly tip/tilt - that reduce coronagraphic performances at 1.2 lambda/D and above. A Low-Order WaveFront Sensor (LOWFS) is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Julien Lozi , Ruslan Belikov , Glenn Schneider , Olivier Guyon , EugenePluzhnik , Sandrine J. Thomas , Frantz Martinache

Reconfigurable intelligent surface (RIS)-aided wireless communications have drawn significant attention recently. We study the physical layer security of the downlink RIS-aided transmission framework for randomly located users in the…

Information Theory · Computer Science 2021-04-09 Jiayi Zhang , Hongyang Du , Qiang Sun , Bo Ai , Derrick Wing Kwan Ng

Intelligent reflecting surface (IRS), which consists of a large number of tunable reflective elements, is capable of enhancing the wireless propagation environment in a cellular network by intelligently reflecting the electromagnetic waves…

Signal Processing · Electrical Eng. & Systems 2021-06-10 Tao Jiang , Hei Victor Cheng , Wei Yu

We present a determination of the bispectrum of the flux in the Lyman-alpha forest of QSO absorption spectra obtained from LUQAS which consists of spectra observed with the high resolution Echelle spectrograph UVES. Typical errors on the…

Astrophysics · Physics 2009-11-10 M. Viel , S. Matarrese , A. Heavens , M. G. Haehnelt , T. -S. Kim , V. Springel , L. Hernquist

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

LiteBIRD, a forthcoming satellite mission, aims to measure the polarization of the Cosmic Microwave Background (CMB) across the entire sky. The experiment will employ three telescopes, Transition-Edge Sensor (TES) bolometers and rotating…

We study a mid-order wavefront sensor (MOWFS) to address fine cophasing errors in exoplanet imaging with future large segmented aperture space telescopes. Observing Earth analogs around Sun-like stars requires contrasts down to $10^{-10}$…

Instrumentation and Methods for Astrophysics · Physics 2024-09-10 B. Buralli , M. N'Diaye , R. Pourcelot , M. Carbillet , E. H. Por , I. Laginja , L. Canas , S. Steiger , P. Petrone , M. M. Nguyen , B. Nickson , S. F. Redmond , A. Sahoo , L. Pueyo , M. D. Perrin , R. Soummer

We carried out an unbiased, spectroscopic survey using the low-resolution module of the infrared spectrograph (IRS) on board Spitzer targeting two 2.6 square arcminute regions in the GOODS-North field. IRS was used in spectral mapping mode…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 B. Bertincourt , G. Helou , P. Appleton , P. Ogle , G. Lagache , T. Brooke , J. -D. Smith , K. Sheth , D. Dale , M. Harwit , J. -L. Puget , H. Roussel

Intelligent reflecting surface (IRS) is a new and revolutionizing technology for achieving spectrum and energy efficient wireless networks. By leveraging massive low-cost passive elements that are able to reflect radio-frequency (RF)…

Information Theory · Computer Science 2019-11-12 Qingqing Wu , Rui Zhang

We describe the redmonster automated redshift measurement and spectral classification software designed for the extended Baryon Oscillation Spectroscopic Survey (eBOSS) of the Sloan Digital Sky Survey IV (SDSS-IV). We describe the…

The James Webb Space Telescope produces some of the highest sensitivity imaging of the cosmos across all instruments. One of them, the NIRISS Fine Guidance Sensor, provides guide star imaging with a passband of 0.6 to 5 microns through two…

Instrumentation and Methods for Astrophysics · Physics 2024-05-10 Derod Deal , Néstor Espinoza

A trace gas sensor, based on quartz-enhanced photoacoustic spectroscopy (QEPAS), consisting of two acoustically coupled micro-resonators (mR) with an off-axis 20 kHz quartz tuning fork (QTF) is demonstrated. The complete acoustically…

Instrumentation and Detectors · Physics 2016-10-03 Mikael Lassen , Laurent Lamard , Yuyang Feng , Andre peremans , Jan C. Petersen