... For the first balloon flight of the Nuclear Compton Telescope (NCT) we have simultaneously reduced lowenergy background and enabled hard X-ray imaging by enshrouding the top of the instrument in a tin shield (bottom had BGO shielding), with part of the shield having strategically placed holes -- a 10% open coded aperture mask working up to 80 keV in conjunction with the finely pixellated double-sided Ge strip detectors. ... Key words: Compton telescope, coded mask, hard X-ray imaging, NCT. ...

We model the spectral chanages of late oxygen-rich Miras observed in different pulsation phases. From a combination of variable near-IR spectra and UKIRT spectrophotometry of the 9.7 \mu m silicate dust emission feature in different phases we study the influence of the changing atmospherical circumstances on the conditions in the circumstellar dust shell. ... A comparision with the modelling results for another long period Mira U Ori is also provided. ...

. The wavelength is reduced here . and increased here . Previous slide . Next slide . Back to first slide . View graphic version .

... Left: A POSSM plot of the uncalibrated spectrum of DA 193 at 1.66 GHz on a baseline Bear Lakes to Noto. ... The phase slope as a function of frequency is clear evidence for a small delay error in the correlator model. Right: The same data as shown on the left, but corrected for a delay error and a residual fringe rate. ... Left: A VPLOT plot of the uncalibrated amplitude (upper frame) and uncalibrated phase (lower frame) as a function of time for the source DA 193 on a baseline HartRAO to Noto. ...

Общая Астрономическая Конференция > Практика > Астрономические наблюдения > Что-то не верится . ... Просмотр полной версии : Что-то не верится . frog . 12.01.2004, 03:39 . Leave the LCD off . The LCD viewfinder is the main source of noise for the CCD in digital cameras, with the effect increasing significantly with exposure time.Вот ссылка: FAQ (http://mysite.verizon.net/~vze4r2c2/Astro/AstroDigiCamFAQ.html#community) . Unforgiven . ... LCD экраны греются довольно значительно. ...

ON THE IMPACT OF THE GALACTIC ABERRATION ON VLBI-DERIVED PRECESSION MODEL Z.M. MALKIN Pulkovo Observatory Pulkovskoe Ch. ... Corrections to adopted precession rate are usually computed from the linear trends in long-term time series of celestial pole offset (CPO), which are the differences between the measured and the theoretical coordinates of the celestial pole. ... CONCLUSIONS We have estimated the impact of GA on parameters of precession-nutation model derived from VLBI observations. ...

Chair of solid state physics . ... Spectroscopy of semiconductors and dielectrics. ... Interband transitions and optical properties of semiconductors. ... Optical properties of metal in a Drude-Lorentz model. Excitons in solids. ... Impurity states in dielectrics and semiconductors. Optical orientation of electron and exciton spins in semiconductors. ... General insight onto interband transitions: electron-radiation interaction, quantum theory of optical transitions in semiconductors. ...

... The addresses specific calibration schemes and how they relate to the way in which ohmic different antenna parameters. of antenna loss into commonly second section loss enters into 1 Antenna Parameters We wish to maintain the fundamental relationship between the antenna effective area, Ae , and the power collected from an unpolarized plane wave of flux density S by a single mode and single polarization feed/transmission line system P= 1 Ae S 2 (1) where is the bandwidth. ...

ASTEROIDAL DAMAGE TO THE EARTH: IMPLICATIONS BY ASTEROIDS ­ RUBBLE PILES. ... 13, Moscow 119892, Russia, E-mail:san@sai.msu.ru In the cause of asteroids ­ rubble piles its effective cross-section of collision to the Earth is determined not by consolidated body, but by cluster of its fragments. Since the stage of rubble ­ piles may be ~108 years (see our communication at previous symposium), it may be significant for estimation the asteroidal damage to the Earth. ...

pro cormass2,list ; ;procedure to pre-process CorMASS 'differenced' images to correct for reset ;voltage decay effects seen in NICMOS3 images. ... Sep '00 ; ; on_error,1 nl=numlines(list) ;find number of files print,'nl: ',nl files=strarr(nl) openr,lun,list,/get_lun readf,lun,files free_lun,lun for i=0,nl-1 do begin oldim=float(readfits(files[i],hdr)) d=size(oldim,/N_DIMENSIONS) if d GT 0 then begin magicsub2,oldim,procim sxaddhist,'Reset Decay Corrected w/ MagSub2',hdr,/PDU name=str_sep(files[i],'.' ...

... Usage of the contemporary methods of noiseproof coding in the projects of the Space researches " . ... In the report the basic principles and effectiveness criteria of noiseproof coding application in problems of high veracity for digital communication maintenance at a very large distance are esteemed. ... Usage of concatenating coding methods on the basis of MTD for simple and effective decoding is offered at problem solving of a long-distant Space communication and remote sensing of the Earth (RSE...

... News . ... Pre-university education . ... Samara University scientists have developed a technology of new-designed photoelectric converters for solar batteries of spacecraft. ... The new solar batteries will be as much effective as their contemporary nanoheterostructured counterparts surface-supported by germanium, and the cost will be five times cheaper. ... Scientists of Samara University (joint SSAU and SSU) developed a technology basis of new silicon-based photoelectric converters (FEC). ...

... Bad Astronomy . ... Every few months, one of a series of questions comes up on the USENET group sci.astro involving tides, or the rotation of the Moon, or the recession of the Moon from the Earth. ... Why the Moon's rotation period is the same as the length of time it takes to orbit the Earth (same as number 1, but phrased differently). ... But when this happens, the time it takes for the Earth to rotate once will be slowed to exactly the same time it takes for the Moon to go around the Earth once! ...

The hotbed effect (hothouse effect) in the planets atmosphere is the inside atmosphere layers heating (of the Earth, Venus etc.), due to the transparent planet atmosphere for the main part of solar radiation (in optical range). In the atmosphere of the Earth this radiation is absorbed by the molecules of H2O, C02, O3 and others. ... As a result of human activities the CO2 content is increasing (and the other gases, absorbing in infrared range). ...

Super Rocket Targets . NPO MOLNIYA has been designing rockets-targets for over 30 years using the great experience in crea-ting anti-aircraft guided rockets (AGR) for C-25M. On the basis of B-300 anti-aircraft rockets which expired their service life, there were designed, tested and put into the serial production the following types of the rocket - ... The analogue of this system successfully passed the state tests with the ZVEZDA-4 rocket-target. ...

Text of report The subject if our report is the influence of the structure and physics of the uppermost superadaibatic layers on the oscillational spectrum of p-modes. ... In our report we will try to use a most simple representation of the spectrum, plotting the differences between theoretical (that is models') and observational frequencies against a frequency. ... It allow us to focused on the effects of the uppermost layers and ignore possible sophistications from effect of more deeper layers. ...

... In electron-positron colliders, effect of the lattice modification by opposing bunch focusing on the equilibrium radiation emittance is important at high values of the space charge parameter, so one should correctly evaluate this dynamic radiation emittance of the weak beam, which may differ a lot from the nominal emittance, already in the linear beam-beam force model. ... The linearized beam-beam force is equivalent to focusing insertion in linear lattice of the collider. ...

... astro-ph . ... Whitespace-separated words are treated as AND ed. Show 10 50 100 articles per page in Full Compact mode . ... Quasar Variability in the Framework of Poissonian Models . ... It is shown that in this very general framework the well established anti-correlation between variability amplitude and wavelength can only be understood as an effect of an underlying spectral component which remains stable on long time-scales, and is redder than the variable component. ...

. This Directory contains Model of distribution of density, temperature and effective collision freguency of electrons. Yu.K.Chasovitin. 1998. This Directory contains The program RIM98 for calculating the parameters of the ionosphere to use the "Reference Ionospheric Model-98" (RIM-98).Yu.K.Chasovitin. 1998.

. 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