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Modern Giant Segmented Mirror Telescopes (GSMTs) like the Extremely Large Telescope, which is currently under construction, depend heavily on Adaptive Optics (AO) systems to correct for atmospheric distortions. However, a residual blur…

Instrumentation and Methods for Astrophysics · Physics 2023-07-05 Roland Wagner , Jenny Niebsch , Ronny Ramlau

The redshifted 21cm line of neutral hydrogen (Hi), potentially observable at low radio frequencies (~50-200 MHz), is a promising probe of the physical conditions of the inter-galactic medium during Cosmic Dawn and the Epoch of Reionisation…

We describe KAPAO, our project to develop and deploy a low-cost, remote-access, natural guide star adaptive optics (AO) system for the Pomona College Table Mountain Observatory (TMO) 1-meter telescope. We use a commercially available…

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

AKARI currently in space carries onboard a cryogenically-cooled lightweight telescope with silicon carbide mirrors. The wavefront error of the AKARI telescope obtained in laboratory measurements at 9 K showed that expected in-orbit imaging…

Astrophysics · Physics 2015-05-13 H. Kaneda , W. Kim , T. Onaka , T. Wada , Y. Ita , I. Sakon , T. Takagi

The detection and accurate astrometry of fast-moving near-Earth objects (NEOs) has been a challenge for the follow-up community. Their fast apparent motion results in streaks in sidereal images, thus affecting the telescope's limiting…

Instrumentation and Methods for Astrophysics · Physics 2023-07-12 Kritti Sharma , Harsh Kumar , Harsh Choudhary , Varun Bhalerao , Vishwajeet Swain , Bryce Bolin , G. C. Anupama , Sudhanshu Barway , Simran Joharle , Vedant Shenoy

We measure the surface density of i'-band dropout galaxies at z~6 through wide field HST/ACS imaging and ultra-deep Keck/DEIMOS spectroscopy. Using deep HST/ACS SDSS-i' (F775W) and SDSS-z' (F850LP) imaging from GOODS-N (200 arcmin^2), we…

The SDSS-IV Mapping Nearby Galaxies at APO (MaNGA) program has been operating from 2014-2020, and has now observed a sample of 9,269 galaxies in the low redshift universe (z ~ 0.05) with integral-field spectroscopy. With rest-optical…

In this paper, we discuss the benefits of ground-based, adaptive optics (AO) aided observations for star formation research. After outlining the general advantages, we present results obtained during the ALFA science demonstration programme…

Astrophysics · Physics 2015-06-24 M. Feldt , M. Kasper , F. Eisenhauer , S. Hippler

Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), one of three core programs in the Sloan Digital Sky Survey-IV (SDSS-IV), is an integral-field spectroscopic (IFS) survey of roughly 10,000 nearby galaxies. It employs dithered…

The InfraRed Imaging Spectrograph (IRIS) is a first-light instrument for the Thirty Meter Telescope (TMT) that will be used to sample the corrected adaptive optics field by the Narrow-Field Infrared Adaptive Optics System (NFIRAOS) with a…

Consider a perfect AO system with a very fine wavefront sampling interval and a very small actuator interval. If this AO system senses wavefront at a wavelength, lambda_{WFS}, and does science imaging at another wavelength, lambda_{SCI},…

Astrophysics · Physics 2008-11-26 Tadashi Nakajima

The 21cm emission of neutral hydrogen is a potential probe of the matter distribution in the Universe after reionisation. Cosmological surveys of this line intensity will be conducted in the coming years by the SKAO and HIRAX experiments,…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Dionysios Karagiannis , Roy Maartens , Liantsoa Randrianjanahary

We correlate the positions of radio galaxies in the FIRST survey with the CMB lensing convergence estimated from the Atacama Cosmology Telescope over 470 square degrees to determine the bias of these galaxies. We remove optically…

Here we describe a simple, efficient, and most importantly fully operational point-spread-function(PSF)-reconstruction approach for laser-assisted ground layer adaptive optics (GLAO) in the frame of the Multi Unit Spectroscopic Explorer…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 Thierry Fusco , R. Bacon , S. Kamann , S. Conseil , Benoit Neichel , Carlos Correia , Olivier Beltramo-Martin , Joel Vernet , Johann Kolb , Pierre-Yves Madec

Adaptive optics (AO) is a powerful tool employed across various research fields, from aerospace to microscopy. Traditionally, AO has focused on correcting optical phase aberrations, with recent advances extending to polarisation…

The redshifted 21 cm brightness distribution from neutral hydrogen is a promising probe into the cosmic dark ages, cosmic dawn, and re-ionization. LOFAR's Low Band Antennas (LBA) may be used in the frequency range 45 MHz to 85 MHz (30>z>16)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 H. K. Vedantham , L. V. E. Koopmans , A. G. de Bruyn , S. J. Wijnholds , B. Ciardi , M. A. Brentjens

Understanding when and how reionization happened is crucial for studying the early structure formation and the properties of first galaxies in the Universe. At $z>5.5$, the observed IGM optical depth shows a significant scatter, indicating…

We describe the current on-sky performance of the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument on the Subaru telescope on Maunakea, Hawaii. SCExAO is continuing to advance its AO performance, delivering H band Strehl…

Solar white-light flares (WLFs) are those accompanied by brightenings in the optical continuum or integrated light. The White-light Solar Telescope (WST), as an instrument of the Lyman-alpha Solar Telescope (LST) on the Advanced Space-based…

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