... Green and blue curves - CYGAM telescope (squares - no constraints on the angle a , triangles - a <0.5 0 ); red curve - EGRET telescope. Effective area versus photon incidence angle to relative the longitudinal telescope axis (squares - no constraints on the angle a , triangles - a <0.5 0 , spectral index g= 2). ... Angular resolution for normal to the axis X incidence versus source power law spectrum index (squares- no constraints on the angle a , triangles- a <0,5 0 ). ... CYGAM (PDF, 450 Kb) . ...

... Target Location in Aperture / 32-2 . ... Location of Image on Diode Array / 32-7 . ... Calibration Accuracies / 32-16 . ... Overall FOS calibration accuracy and the quality of your observations are governed by a variety of factors both internal and external to the instrument, which include: . ... The location of the target on the photocathode, which, in addition to having been influenced by acquisition-related consequences, is affected by FOS mechanism positional repeatability. ...

... Let us first find out which way -- rise in spectral resolution with some loss in the S/N ratio or increase in the S/N ratio with a fixed spectral resolution -- is better for the purpose of reduction of equivalent width determination errors. ... N -- number of counts for 1 ? ... line equivalent width, . ... Thus if the spectral resolution is managed to be increased (i.e. to decrease )without loss in the number of counts falling at 1 ?, the equivalent width measurement error is then proportional to . ...

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. ...

... Publications based on data obtained with the CRIRES instrument should quote the following reference paper: K ufl, H.U. et al. ... Questions related to service mode observations and proposal preparation should be addressed to the User Support Department. Questions related to visitor mode observations should be addressed to Paranal Science Operations . ... Overview: a short description of the instrument . ... Manuals: links to all the documents related to CRIRES. ... Instrument Operations Team . ...

CHIANTI - an atomic database for emission lines. ... K.P.Dere, E.Landi, H.E.Mason, B.C.Monsignori-Fossi, P.R.Young, 1997, A , 125, 149 . Article: Available from ADS . The Arcetri Spectral Code for thin plasmas . E.Landi M.Landini 1998, A , 133, 1 . ... E.Landi, M.Landini K.P.Dere, P.R.Young, H.E.Mason, 1999, A , 135, 339 . ... K.P.Dere, E.Landi, P.R.Young, G.Del Zanna, 2001, ApJS, 134, 331 . ... G.Del Zanna, B.J.I.Bromage, E.Landi, M.Landini, 2001, A , 379, 708 . ...

RELATIVE SUNSPOT NUMBERS Description of Data from SGD Explanation of Data Reports: Relative Sunspot Numbers -- The relative sunspot number is an index of the activity of the entire visible disk of the Sun. ... The provisional daily Zurich relative sunspot numbers, Rz, were based upon observations made at Zurich and its two branch stations in Arosa and Locarno and communicated by M. Waldmeier of the Swiss Federal Observatory. ... This indicates the uncertainty above and below the predicted number. ...

... Archives . ... Another exciting news (with no use) . ... One of those rabbits is hunting online lectures useful for everyone. Prof. Feynman?s lectures have great reputations but they have been hard to come by. ... Thanks to Bill Gates and Microsoft Research , although it is a belated news, I?m very delighted to say ?Feynman lectures are online.? ... I attribute its lack of discussion in the slog to its late debut. ... Comment ( RSS ) | ... Chandra Blog . ... Entries (RSS) and Comments (RSS) . ...

... Time related attributes: . observation related: DATE_OBS and DURATION required by XMM-SOC-ICD-0006-SSC ([ 3 ]), write also DATE_END and OBSSTART , OBSSTOP . ... SAS_VERBOSITY should be set to `Sparse' (4) for normal processing and `Verbose' (5) for more detailed processing. Values of 6 and higher may yield quite a number of messages related to rejected events (MIPs) depending on CCD number and instrument mode. SAS_MEMORY_MODEL should be set to `high' for normal processing. ...

Contents. planet: 5 - Jupiter satellites: J1 - Io : 81, J2 - Europa : 24, J3 - Ganymede :129, J4 - Callisto : 36 total number: 270 type: relative dates: 1996-1997 observatory: see observatories list in the comments Reference. Emelianov N. V., Vashkovjak S. N. (2009) Astrometric results of the observations of the mutual occultations and eclipses of the Galilean satellites of Jupiter in 1997. ... X coordinate in arcseconds (topocentric for mutual occultation or heliocentric for mutual eclipse) 10. ...

The examples of the errors. ... Observations with ordinary values of the "Mean error of single observation" Obj Code DT RA (O-C) DEC (O-C) mag z h m s " ° ' " " ° 3907 761 1998 08 24.383673 3 17 44.739 0.28 +30 46 00.84 -0.08 15.8 18 3907 761 1998 08 24.409133 3 17 46.152 0.28 +30 46 10.85 0.12 15.8 11 3907 761 1998 08 25.392523 3 18 40.107 0.33 +30 52 27.69 0.04 15.4 15 Total mean value of 3 observations 0.297±0.017 0.027±0.058 Mean error of single observation 0.029 0.101 COMMENT. ...

Astronotes Armagh Planetarium's Stellar Blog! ... This image combines orbital imagery with 3-D modelling to show flows that appear in spring and summer on a slope inside Mars' Newton crater. ... Warm season flows on a slope in Newton Crater, possible evidence of salty liquid water active on Mars today. Image credit: NASA) . ... Frozen water is common on and under the surface of Mars but these images are the best evidence to date for the presence of liquid water on the Martian surface today. ...

Subject, Object and Problems of Astrophysics. Practical and Theoretical Astrophysics. ... Visual Telescope; Problems Which Are Solved with the Its Help. ... Resolution of Telescopes. ... Effectiveness of Telescope in Respect of Resolution. ... Optical Power of Telescopes for Star-like and Extensive Objects. Boundary Magnitude. Reasons of Light Dissipation in Telescopes. ... Spectral Instruments in Astrophysics. ... Basic Photometrical Ideas, Magnitudes and Their Measurement. ...

... Series 4000 filters thread into the barrels of virtually all 1.25" eyepiece brands. Meade Series 4000 filters are a large 26mm in clear aperture and are manufactured from the purest crown optical glass, dyed-in-the-mass ( not "color coated"); there are no finer filters available for telescopic applications. ... For visual applications Series 4000 filters thread into the barrels of all Meade 1.25" eyepieces, and into the barrels of virtually all other 1.25" eyepiece brands as well. ... Meade 4M | ...

... A document window is shown, with 8 lines (numbered 1 to 8), each 24px high. The text of the "outer" box (at the end of line 1, halfway into line 2, and halfway into line 3) is shifted upward 12px. The text of the "inner" box, thought shifted upward as well, has been relatively positioned so that it lies in its normal flow position at the end of line 2. ... The lines, as they appear in the image, contain: Start 1 Beginning of body contents. 2 of outer contents. Inner contents. ...

CONTENTS Volume 25 Number 1 (January 1998) . ... A. A. Ubachukwu . SPECTRAL INDEX ASYMMETRIES IN POWERFUL RADIO SOURCES: COSMOLOGICAL EVOLUTION VERSUS LUMINOSITY SELECTION EFFECTS . ... A. G. Gunn . ... A MEDIEVAL IRISH TREATISE ON ASTRONOMY RECALLED, WITH A MEMOIR OF ITS TRANSLATOR AND EDITOR, MAURA POWER (1887-1916) . ... 1995-1999 Irish Astronomical Journal, Downshay, 12 Heather Lea Avenue, Dore, Sheffield S17 3DJ, S. Yorkshire, United Kingdom WWW Contact: Alastair G Gunn Back to IAJ Home Page ...

... (degrees) b2 galactic latitude (degrees) sgl supergalactic longitude (degrees) sgb supergalactic latitude (degrees) pgc PGC name *** alphabetical ** ident1 1st name (NGC,IC,UGC,ESO...) *** alphabetical ** pa position angle (N- E) in degrees typ morphological type (e.g. 'E','Sab','SBa','SO') *** alphabetical ** ring 'R' for Ring galaxies, otherwise ' ' (blank) *** alphabetical ** multiple 'M' for multiple galaxies, otherwise ' ' (blank) *** ...

... Up: Data Analysis Applications . ... We present aspects of the Data Analysis of the Short Wavelength Spectrometer (SWS) on-board ESA's Infrared Space Observatory (ISO). The general processing from the raw telemetry data of the instrument, up to the final calibrated product is described. ... The data is checked for saturation, corrected for reset pulse after-effects, linearized (AC correction), cross-talk corrected and converted to voltages. ... fitting cosine functions to the RSRF corrected data . ...

Next: ATCA Spectral Line Correlator Up: Spectral Line Data Reduction Previous: Spectral Line Data Reduction . Because of the Doppler effect, the observed frequency of a spectral line can be related to the radial velocity between the observer and the source. ... where v is the radial velocity, the observed frequency, the rest frequency, and c is the speed of light. ... Next: ATCA Spectral Line Correlator Up: Spectral Line Data Reduction Previous: Spectral Line Data Reduction Miriad manager . ...

... The experience of determination of the link between radio sources and dynamical reference frames is presented. To obtain this connection we used a series of very long baseline interferometry (VLBI) observations of the spacecraft Phobos-2 and angularly nearby quasars. ... The dynamical reference frame is determined by equator and equinox of these ephemerides. ... References . ... The relative orientation of the radio and dynamical reference frames can be described by a sequence of three rotations . ...