Analysis of the modes and behaviour of a Multiconjugate Adaptive Optics system . M. Le Louarn and M. Tallon . Accepted for publication in JOSA A, 2001 . ... E. Viard, M. Le Louarn , N. Hubin . ... The future of Adaptive Optics . M. Le Louarn . ... Le Louarn, M. and Hubin, N. and Sarazin, M. MNRAS, 317 , 535--544, 2000 . ... Le Louarn, M. and Tallon, M. Proc SPIE, 4007 , 2000 . ... Le Louarn, M. and Dainty, C. and Paterson, C. and Tallon, M. Proc SPIE, 4007 , 2000 . ...

Astronomy Picture of the Day . ... 18.02.2000 . ... Credit: AO Staff , Keck , LLNL Explanation: From the Earth's surface, Neptune usually appears as a fuzzy blotch. The blurring effects of the Earth's atmosphere deny clearer images. ... February 2000 . ... 1999 2000 . ... NASA Web Site Statements, Warnings, and Disclaimers . ... U. Based on Astronomy Picture Of the Day . Publications with keywords: neptune - adaptive optics . Publications with words: neptune - adaptive optics . ...

... 2000 February 18 . Neptune through Adaptive Optics . Credit: AO Staff , Keck , LLNL . Explanation: From the Earth's surface, Neptune usually appears as a fuzzy blotch. The blurring effects of the Earth's atmosphere deny clearer images. ... The above image of Neptune in three infrared colors demonstrates the clarity of the new technique - as compared to an image of Neptune from Keck II without AO . ... About APOD | ...

... Since variance is the square of standard deviation, the obvious thing to to is to divide the input variance image by the square of the exposure map . Remember that, regardless of the value of readvarianceset , the task makes use of an internal variance image if either writevarianceset =`yes' or smoothstyle =`adaptive'.) ... However, recall that adaptive smoothing makes use of the input variance to calculate the signal-to-noise ratio (SNR) of the input image. ...

The first near-infrared IFU spectrograph was the 3D instrument , constructed by the Max Planck Institut f r Extraterrestrische Physik. ... An effective slit width of 0.1" was chosen in order to probe to spatial scales approaching the 0.07" diffraction-limited image core size expected from the Gemini adaptive optics system at 2.2 microns while maintaining an acceptable field-of-view. ... The field mirror array then feeds the spectrograph collimator mirror (seen at left in the above figure). ...

The night after the John Glenn program, I pitched the terraforming idea to my students. I asked them if they'd like to terraform Mars as a big class project; I wanted to throw the idea to them and see how they would react. Already I had a vision of splitting the class into several groups and having each group take charge of a portion of the project. ... Following my initial idea on how to conduct the project, I split the class into six groups, each student choosing his or her group. ...

... Correcting ETC Calculations of CCD Spectral Observations for CTE Effects . ... HST Overview . Overview . ... Post-Observation . ... ETC . ... ID: CL Script for Applying CTE Loss to Output of Spectroscopic ETC . ... However, the STIS ETC calculations do not incorporate these CTE effects as yet. ... The output from this script should then be used to calculate the appropriate input flux level for a second run of the ETC, which will then yield output which is corrected for the CTE effect. ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Australia Telescope Online Archive (ATOA) . ... Parkes | ... Australia Telescope 20GHz Survey . ... Visiting Parkes radio telescope . Visiting Australia Telescope Compact Array . ... Parkes radio telescope webcam . ...

... Laboratory for Spectroscopy of Molecular Structures . ... Optics and spectroscopy of molecular and liquid crystals, fullerenes, superthin molecular films. Optical studies of structure, phase transitions, pretransitional phenomena, structural modifications in external field and under high pressure. ... Methods developed in the laboratory enable to determine in free standing films of different types liquid crystals values of polarization, two-dimensional constants of orientational elasticity. ...

... SiD workshop, Fermilab, April 9-11 2007 April 9, 2007 Nick Sinev, SiD design Workshop, Fermilab 1 Topics 1. ... What and how was simulated What and was One column clusters effects Accepted background density Hit reconstruction efficiency Hit efficiency How to improve efficiency Conclusions April 9, 2007 Nick Sinev, SiD design Workshop, Fermilab 2 What is this April 9, 2007 Nick Sinev, SiD design Workshop, Fermilab 3 Marty's idea Shift charge in neighboring columns in opposite directions. ...

... If you use adaptsmooth to do your own science, please acknowledge its use in your publications by adding a sentence like тАЬThis work has made use of the adaptive smoothing code adaptsmooth , developed by Stefano Zibetti and available at the URL http://www.arcetri.astro.it/~zibetti/Software/ADAPTSMOOTH.html тАЭ and reference the following papers: Zibetti, S., 2009, arXiv:0911.4956 ; Zibetti S., Charlot S., Rix H., 2009, MNRAS, 400, 1181 . ...

... the radiative transfer equation (RTE) for the randomly-irregular magnetized plasma has been derived on the base of general grounds of the multiple scattering theory . ... Solutions of several absolute tasks of the scattering theory have been obtained (on the optical depth of the ionospheric plasma layer, on the value of radio wave anomalous attenuation, on anomalous refraction, on the backscattered signal intensity for the source being placed within a plasma layer). ...

... Primordial theory review : Dick Bond . Defects and the CMB review : Andy Albrecht . ... Gravitational wave contribution to CMB anisotropies : V.B. Lukash and E.V. Mikheeva . C_l from cosmic strings : Lloyd Knox . Some aspects of CMB anisotropies induced from topological defects : Mairi Sakellariadou . ... CMB anisotropies from scaling sources : Ruth Durrer . ... SZ observations I : Sarah Church . ... Holes in the microwave sky? ... Detecting cosmic strings in the CMB : James Robinson . ...

... Archives . ... Please, do not confuse adaptive filter (hereafter, AF ) with adaptive optics (hereafter, AO ). ... Not just the hardware part, but I was interested in how astronomers have applied theories and algorithms of AF to acquire cleaner data that are processed with speed and efficiency. ... A long story short, against my expectation for frequent allusion from ADS, adaptive filter turned out to be almost [MADS]. ... Tags: adaptive filter , adaptive optics , MADS . ... Comment ( RSS ) | ...

. The two W. M. Keck Telescopes on Mauna Kea, Hawaii, observing the galactic center. The lasers are used to create an artificial star in EarthтАЩs upper atmosphere, which is then used to measure the blurring effects of the lower atmosphere (the effect that makes the stars twinkle in the night sky). The blurring gets corrected in real time with the help of a deformable mirror. This is the adaptive optics technique. // Credit: Ethan Tweedie

Effect of chromospheric activity on the mean colours of late­type stars P. Amado and P.B. Byrne A&A, accepted July 96 In this paper we show, for the first time, the effect of activity on the (U \Gamma B) o vs. B \Gamma V ) o colour­colour diagram for a large sample of late type stars. we clearly see that for single­lined spectroscopic RS CVn systems there exists an ultraviolet excess over that recorded for quiescent stars of the same spectral type. ...

... Using a simple 2-D Gaussian Point Spread Function (PSF) on a constant (flat) sky background, I derive a theoretical photometric and astrometric performance model for analytical and digital PSF-fitting stellar photometry. ... The photometric performance is maximized when either the effective background area or the effective-background-level measurement error is minimized. ... An important, but frequently ignored, noise source is the uncertainty of the measurement of the effective background level ( )...

... 172 ] Briefly, the count rate at the detector from a source at a redshift z is . ... Figure 55 shows the ``Green functions'' for the double compact binary merging rate   evolution assuming no collapse anisotropy. ... Another way that diverse peculiarities in the - distribution induced by the sources evolution could arise is connected with a possible non-monotonic character of the star formation rate in galaxies. ... 22 ] Figure  56 shows two-dimensional cuts through the parameter space. ...

... SCIENCE AND BUSINESS . Such a trifle as a starry night sky of largest observatories turned out to be a small change coin in commercial bargains for exclusive communal services in Russia, and for a few elite flats in penthouses in Ukraine. SCIENCE AND BUREAUCRATISM . ... Till in Russian) . ... Clericalization of science and education (Till in Russian). ... Researcher of the Sternberg Astronomical Institute, The Moscow University. ... SAI home page . ... October, 2008) . ... November, 2007) . ...

... The behaviour of the polarization efficiency (see Eq. ( 14 )) for non-absorbing and absorbing spheroids is shown in Fig. 11 for the case when a maximum polarization is expected (PF alignment, ). ... Figure 11: Polarization efficiency against for prolate and oblate spheroids with and , picket fence orientation, . The size/shape effects are illustrated. ... Figure: Polarization efficiency as a function of particle equivolume radius for prolate core-mantle spheroids with and , PF orientation, . ...