. Diameter of circular antenna . 576 m . Number of antenna elements . 895 . Size of an element . 11.4 x 2 m . Geometrical area . 15000 m 2 . Effective area of full circle . 3500 m 2 . Wavelength range . 1 - 50 cm . Frequency range . 610 - 30000 MHz . Maximum angular resolution . 2 arcsec . Accuracy of coordinate determination . 1-10 arcsec . Flux density limit . 0.500 mJy . Absolute brightness temperature limit . 0.050 mK . Tracking time (South sector + Flat mirror) . 1-3 h . [RATAN-600 Homepage]

. Diameter of circular antenna . 576 m . Number of antenna elements . 895 . Size of an element . 11.4 x 2 m . Geometrical area . up to 20000 sq.m . Wavelength range . 1 - 50 cm . Angular resolution . 2 - 400 arcsec . Accuracy of coordinate determination . better than 1 arcsec . Limiting sensitivity (1994): . flux density . 0.500 mJy . brightness temperature . 0.050 mK

In the PROJECT we are using the following peculiar . features of RATAN-600 . ... Brightness temperature sensitivity being equal to the antenna temperature sensitivity .. ... Receiver system .. ... Using aperture averaging effect. dual- beam and dual (multi-) frequency filtration, we demonstrated full filtration of the atmosphere noise down to the receiver noise at all scales of acoustics peaks ( Fig.1 , Fig 2 ). ... We select this frequency as the central one in our project. ... Antenna surface . ...

... HST . What is the meaning of the 2x2 resolution element in the ACS ETC for an extended source ? ... HST Peer Review Process . ... HST Overview . ... What do I do if my source is larger than the 2x2 element ? When you are using any ACS ETC (imaging, spectroscopic or ramp) with an extended source, the ETC does all calculations for a boxsize of 2x2 pixels, or one resolution element. ... The 101x101 box is 2500 time the size of one resolution element and the square root of 2500 is 50.) ...

To main of Laboratory . The research work and design of optical and optical-electronic devices are carries out by laboratory staff: . ... Lens: . ... In the layout 1 prism systems perform functions of dispersive element, corrector of aberrations, optical reducer. ... Spectral range 200 - 400 nm; . ... Back Forward . ... The main corrector's function are compensation of field aberrations of the main spherical mirror of a telescope (diameter of 600 mm, f'=1200 mm) and increase aperture ratio. ...

The aim of this section of the course is to familiarise you with celestial Coordinates. ... I found some good notes explaining the celestial coordinate system on the web: . ... 1st Dec: 04hr, 00min In addition to the equatorial coordinates described in the notes above, astronomers also use (at least) two other coordinate systes: galactic coordinates and ecliptic coordinates. ... Ecliptic coordinates use the ecliptic (the Earth's path around the sun) as the equator, and are used for solar system work. ...

The parameter brief (with its actual uncertainty sbrief) is the mean effective surface brightness in B-band , i.e. the mean surface brightness inside the effective aperture (the circular aperture enclosing one-half the total flux). It is expressed in mag arcsec -2 . ... 2) from the mean surface brightness "LV" inside the effective isophote (elliptical isophote enclosing one half the total flux) measured by Launberts&Valentijn (1989) . ... Effective radius . ... HyperLeda . ...

... The collecting area is increased by nesting concentric mirror pairs, all having the same focal length. ... Figure shows the largest optical element being ground at HDOS. ... X-ray testing demonstrated that the CXO mirrors are indeed the largest high-resolution X-ray optics ever made; the nominal effective area (based on the ground calibrations) is shown as a function of energy in the left panel of Figure , along with those of their Einstein and ROSAT predecessors. ...

... arfgen (arfgen-1.73.3) [?? ... arfgen simply constructs the appropriate quantities from the CAL, in the form of vectors of discrete energy-dependent elements, and combines these data multiplicatively to form the ancilliary response. ... This is already taken into account by the CAL in the call to CAL_effectiveArea. The user can enable or disable the effective area, filter transmission, QE or grating attenuation by setting the relevant parameter (eg modeleffarea ) to true or false respectively. ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

Smithsonian Astrophysical Observatory Memorandum To : From Date: Re: M. Cappi, Strong Gravity SDT/YB Team, XMS team : M. Garcia April 14, 2010 XMS high/mid/low resolution event rates for bright AGN mrg-2010-02v2 This memo arises out of the concern that the bright AGN that will be used to observed strong gravity effects ­ in particular those for which time-resolved measurements of test particle orbits will be made ­ may generate counting rates in the XMS that are sufficient to overwhelm it. ...

... Astrophysics Group . ... MRAO Telescopes . RYLE . ... The Ryle Telescope, formerly known as the 5-km Telescope, was originally designed as an 8-element E-W interferometer with the objective of mapping individual radio sources with an angular resolution as good as that of large optical telescopes when it was built in 1971. ... The Ryle Telescope in a compact configuration. (б© Mullard Radio Astronomy Observatory, 1995.) ... For information on other MRAO telescopes, follow the links on the left. ...