... Stellar Evolution is driven entirely by the never ending battle between Pressure and Gravity . As imbalances are reached, the star is driven to find a new Energy source. ... Pressure and gravitational forces are equal, the star is stable and its core is sufficiently hot to fuse Hydrogen into Helium More about main sequence stars . ... The luminosity generated by the core fusion of Helium into Carbon is far greater than the shell luminosity associated with the fusion of Hydrogen into Helium. ...

... Standard magnitudes can only be computed for the U, B and V filters and hence the only standard colours that can be calculated are U-B, B-V and U-V. An important point to note, is that these standard colours can be computed using the following instrumental colours - U-B, B-V, U-V, (UVW1-U), (UVW1-B), (UVW1-V), (UVW2-B) and (UVW2-V). ... The program loops through these colours and if the relevant instrumental magnitudes are present computes the standard magnitudes and standard colour. ...

... The absolute flux calibration of NICMOS will be calculated from observations of standard stars with known flux distributions F( ). ... In order to expand the set of IR standard stars in the appropriate flux range for NICMOS, M. Rieke, R. Thompson, and collaborators at the University of Arizona are making photometric observations of solar-analog stars, which will be used to normalize the solar spectrum to the observed IR magnitudes. ... Relative flux references accurate to 1.5% for standard...

Next: Hierarchical Wiener filtering Up: Noise reduction from Previous: The convolution from . Let us consider a measured wavelet coefficient at the scale i . We assume that its value, at a given scale and a given position, results from a noisy process, with a Gaussian distribution with a mathematical expectation , and a standard deviation : . ... We get: . ... This is done from the study of the variation of the noise between two scales, with an hypothesis of a white gaussian noise; . ...

... I have compiled a list of throughput filter curves from a variety of telescopes, instruments, and surveys. Click on the name of the filter to download it. The first line of each filter is the zeropoint for that filter. If the filter is in the AB system, it is listed as 0.0 (or in otherwords -48.55). ... Filter . Effective Wavelength . ... A_V . ... 0.987 . ... 0.050 . ...

. Position . Logical Name . Description . 0 . D . Stop . 948 . J . Standard Filter J (1.12-1.40?m) . 1896 . SJF . BandPass Filter (0.91-1.12?m) . 2844 . F1 . Hole . 3792 . EPS . LongPass Filter (1.65-2.55?m) . 4740 . H . Standard Filter H (1.48-1.82?m) . 5688 . FHK . BandPass Filter (1.76-2.12?m) . 6636 . K . Standard Filter K (2.00-2.41?m) .

... Interim correlator, ri . ... The programs with "filter" in column 2 are filter programs that read from standard input and write to standard output. The filters are classified as to their data input and output types: . ... BtoB: binary input to binary output . ... Programs Table . ... scan an interim correlator datafile and output a summary of each scan in the file. corstripch . ... read an ainterim correlator or ri datafile and output each scan to a separate file (or a subset of scans). ...

... ATNF Home . About ATNF . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Parkes radio telescope . ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... We discuss variations of the atmospheric extinction coefficients and transformation equations to the standard UBVRI system based on observations of standard stars during 1996-1997 at Siding Spring Observatory using a thinned SITe CCD and coloured glass filters. ... Standard System Transformations . ...

... Previous: Background Fluctuation Analysis from the Multiscale Entropy . ... A new measure of information is defined which is based on noise modeling and incorporates resolution scale. Properties of this measure are discussed. ... Additionally it allows for image noise modeling, and subsequent noise removal. ... Hence information- and entropy-based processing technologies will be necessary for the effective design and implementation of large, future generation, image databases. ...

... U filter . UG1 - 1mm . S8612 - 2mm . WG295 - 2mm . ... BG37 - 3mm . BG39 - 1mm . GG395 - 1mm . ... GG495 - 2mm . BG40 - 3mm . ... OG570 - 3mm . KG3 - 2mm . ... RG9 - 2mm . WG305 - 3mm . Bessell, PASP 102 , 1181, (1990) . ... Bessell, PASP 107 , 672, (1995) . APO Filters Homepage ...

This library currently provides subroutines used to transform theoretical spectra to intermediate and broad-band photometric indices. ... Typical tasks are the response functions and transmission curves for various filters, mirrors and photomultiplier windows. ... The response is zero outside the given wavelength range. ... real . input . Wavelength in nanometres . PHOT_1P21 . ... PHOT_AIR . ... PHOT_ALUM . ... Inputs must be valid as for PHOT_FILTER, PHOT_AIR, PHOT_ALUM and PHOT_1P21. ...

RTT150 . Russian-Turkish 1.5-m Telescope . ... Until 2002 observations were mostly performed with ST-8E CCD in the 1:7.7 Cassegrain focus. ... In April, 2003 telescope was equipped with a larger-size CCD Andor DW436 . ... 2048 x 2048 pixels, . ... Since summer of 2002 the main focal detector of the RTT150 telescope was AP47p CCD in 1:7.7 Cassegrain focus. ... During September 3-13, 2002 works on installation of new autoguiding system ( photo 1 ) were carried out on RTT150 telescope. ...

... Superb optical performance coupled with time proven computerized pointing and tracking has made the LX200 ACF series a best-seller in the high-performance telescope class. ... MeadeтАЩs new LX70 Series offers high-quality German equatorially mounted telescopes with slow-motion controls and heavy-duty steel tripods. ... For crisp wide-field observing and imaging, few optical designs match the performance of a true triple-element apochromatic refractor. ... Meade Standard Field Tripod #07020. ...

splitxyz - filter to divide (x,y,z[, distance ,heading]) data into (x,y,z) track segments . splitxyz [ xyz [ dh ] file ] -C course _ change [ -A azimuth / tolerance ] [ -D minimum _ distance ] [ -F xy _ filter / z _ filter ] [ -G gap _ distance ] [ -H [ nrec ] ] [ -M ] [ -N namestem ] [ -S ] [ -V ] [ -Z ] [ -: ] [ -bi [ s ][ n ] ] [ -bo [ s ] ] ... If xy _ filter is non-zero, the data is first divided into segments and then the x,y values of each segment are filtered separately. ...

Next: AXAF Recipes Up: ROSAT HRI Recipes Previous: Quantum Efficiency Correction (a.k.a. For some observations, a significant amount of data may have been rejected during SASS processing because the background level was higher than the calculated threshold for rejection. ... REJECTED EVENTS . ... The recipe will allow the user to include rejected events in the generation of a new qpoe file and filter on the background level. ... This creates a qpoe file with standard + rejected events. ...

... Data Handling and Products > Data Reduction FAQ > The spectrum of my MOS flux standard star is shifted in wavelength by several pixels. Why is that and how can I correct for it? ... Observing with ESO Telescopes . ... The shift of the flux standard spectrum is caused by a combination of bad centering within the slit and possible wavelength calibration issues. To align the spectrum to the tabulated flux, use the parameter --resp_shift in vmmosscience when determining the response curve. ...

... This method is called once when the filter is loaded. ... This method should return a flag word that specifies the filters capabilities. ... With CONVERT_TO_FLOAT, the filter is called with the image data converted to a FloatProcessor (3 times per image for RGB images). ImageJ will lock the image before calling this method and unlock it when the filter is finished. For PlugInFilters specifying the NO_IMAGE_REQUIRED flag and not the DONE flag, run(ip) is called once with the argument null . ...

... Telescopes . ... CCD photometer . ... One of the principal devices used in observations at the telescope Zeiss-1000 is a CCD photometer. ... The count rates (electron per second) for ADU = 1e - computed throughout the image for U = B = R = I = 20.0 for an object observed at air mass equal to 1.0 with the given version of CCD at the telescope Zeiss-1000 are presented in Table 1. Table 1: Quantum efficiency and count rate in the broad-band system of the CCD photometer of the telescope Zeiss-1000. ...

A computer controlled low light photometer for nightglow observations. Hardware units of portable photometer for low light measurements, especially night glow emission is described. ... Interface card contain three channels of 24 bit counter, 4 channels of 12 bit ADC and the buffer bus for the controlled motors of the altazimuthal fork mounting and filters wheel, the position encoders. ... Where N( ) is output signal photometer generated input light flux F( l ) . ... PMT # . 599 . ...

... Книга Николая Гавриловича Курганова (1725-1796) - талантливого самородка, солдатского сына, пробившегося благодаря своим способностям и трудолюбию в науку и в двадцать лет получивший звание "ученого подмастерья", а тридцать девять - профессора математики и навигации. ПИСЬМОВНИК стал настольной книгой многих поколений русских людей на протяжении четырех царствований - от Екатерины до Николая Первого. ...