... 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. ...