Next: Selection and Multi-Source/Multi-Frequency Datasets Up: Visibility Data Concepts Previous: Selecting UV Data in . A Miriad visibility dataset can contain simultaneous observations at multiple spectral bands, or spectral windows. ... When there are multiple spectral windows, channels are still numbered from 1 to N , where channel 1 is the first channel of the first spectral window, and channel N is the last channel of the last spectral window. ... line=channel,1 . ...

... The x-ray spectral analysis consists of a comparison between the observed pulse height spectrum and a pulse height spectrum calculated using a given spectral model. ... To obtain the spectral parameters for an x-ray source, several steps need to be followed. For each source: . ... obtain the best fit parameters for a spectral model - repeated for each model of interest . obtain a 1-D or 2-D grid of values around the best fit values - this can be done for as many models as desired . ...

The following files list line and continuum emissivities from the Arcetri Spectral Code. ... Ne = 10^8 g-zipped file (phot cm^3 s^-1); Ne = 10^8 g-zipped file (erg cm^3 s-1) . ... File format (html): File format for the continuum files . ... File format (html): File format for binned line emission files The following files list transitions whose emissivities have values greater than a fixed amount (10^-19 phot s^-1 cm^+3 and 10^-30 erg s^-1 cm^+3 respectively): . ...

... Thomson's multiple window method of spectral estimationthomson provides a very good estimate of the power spectrum by measuring the energy contained within a collection of rectangular shaped frequency intervals. ... Often, much of the fine structure of a spectral estimate is due to noise. It should be stressed that while other methods of spectral estimation (such as the Welchoppenheim method) exist, the Thomson method is particularly noteworthy for its precisely defined rectangular frequency bins. ...

... Подставки под телевизоры и Hi-Fi . ... Теплая детская шапка-бини Reima Auva идеально подойдет для прогулок в прохладное время года. ... Современный дизайн и расцветка делают эту шапку модным и стильным предметом детского гардероба. ... Цвет: разноцветный . Коллекция: Весна-лето 2016 . ... Пол: Мужской . ... Цвет: мультиколор. ... Сезон: Весна-лето 2016. ... Цвет: черный . ... Цвет: белый . ... Пол: Женский . ... Цвет: синий . ... Barkan 34.C.B 4D кронштейн - Barkan - Barkan . ...

Next: Conclusions Up: Selection Effects Previous: Inconsistent (or Inconsistently Applied) . Another possible bias, present in this as well as all other surveys which use spectral indices based upon nonsimultaneous data in their selection process, is due to variability. ... In order to minimize the effect of non-simultaneous radio survey data upon our samples, we decided to expand the common definition of flat-spectrum radio sources to extend to (instead of 0.5). ...

Next: Methods for Structuring and Searching Very Large Catalogs . ... We have explored two automated classification methods: supervised classification using Artificial Neural Networks (ANN) and unsupervised classification using Self Organized Maps (SOM). These methods are used to classify IUE low-dispersion spectra of normal stars with spectral types ranging from O3 to G5. This paper describes the application of automated methods to the problem of the classification of stellar spectra. ...

... The Wide Field Spectral Imager ( WISPI ) seen here in the Roll Roof Facility provides visible and near-infrared spectra of the sky across 4 degree fields. ... A computer controlled mounting automates the acquisition of 2-D rastered spectral images. ... Light from the sky enters the large 400mm lens at top center, is imaged on the slit, collimated by the smaller 180 mm lens, and diffracted by the grating at the bottom toward the 200mm lens and CCD camera on the right. ... Camera - 200mm f/2 Nikor ED ...

... December 21, 1997 . ... Advantages are briefly discussed of gaining in spectral resolution, which is accompanied by losses in signal level, as compared with the attempts to improve the accuracy of measurement of line parameters by means of rising the S/N ratio alone with increasing the exposure time. To partially solve the problem of observations of faint objects at the BTA a new design echelle spectrometer is proposed. high resolution spectroscopy . ...

... Credit: KPNO 0.9-m Telescope , AURA , NOAO , NSF Explanation: Astronomers divide stars into different spectral types . ... A few types that best describe the temperature of the star remain in use today. The seven main spectral types OBAFGKM are shown above with the spectrum of a single "O" star at the top followed by two spectra each from the progressively cooler designations, respectively. ... Publications with keywords: stars - spectrum . Publications with words: stars - spectrum . ...

. FLARES . LIMB FLARES . POST FLARE LOOPS . ACTIVATED PROMINENCES FILAMENTS . QUIET PROMINENCES FILAMENTS . 2004 Yu. Kupryakov .

... Solar flare activity is produced by the processes of accumulation and release of energy in an active region. ... In the framework of study of solar active regions, producing powerful flares the researchers from the RATAN-600 radio telescope have detected sources with features in the form of a sharp drop in the intensity of polarized radiation in various parts of the recorded frequency range (2-16GHz), sometimes changing the sign of polarization. ...

XEphem Forum Message . ... Post . ... Spectral Type In Xephem And Tycho2 . ... Post Message | ... is a spectral type in xephem is to draw star . ... There is no spectral type in tycho2, but . ... the spectral type can be derived. ... const char *BvToSpectr(double b_v) { . ... www.astronomy.net . About Astronomy Net | Advertise on Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

H 2 O maser sources spectral data at 22 GHz. I began this project 27.08.1998 for displaying spectral data at 22 GHz of water maser. While data will concerning in base Puschino many year (1979-1998 yy) regular observations of sample of these sources. Sources . R.a. (1950.0) . ... The figures with many years spectral data (day-month-year) . The behavior of flux . The behavior of spectral components . ... All spectra 1981-94 . ... The some spectral component: many year behavior . ...

... IDL procedure to display ; a) a region of spectrum , together with a fit , if supplied, ; b) positions and relative strengths (gf or W_lambda) of lines in ; common atomic spectra may be marked in the lower panel. ; c) lines of sleceted atoms are identified in the top panel ; ; Command arguments: ; specfile - character string - name of file containing spectrum (and fit ) ; assumed to be x,y file with 3- ... Assesses lines in linelist by the strength values "listfr". ...

. The frequency of the spectral maximum f m of the gyrosynchrotron emission vs. the column density of accelerated electrons calculated according to Dulk & Marsh (1982). Curves are shown for various power-law indices ? el of the electron spectrum and magnetic field strengths B . The angle between the line of sight and the magnetic field is 45 degree.

Static Fourier spectrometers are often used for spectral measurements of the ionosphere emissions. There are two main advantages of Fourier spectrometers (FS) - large geometric factor and high spectral resolution; these parameters are two orders better than for grating spectral instruments. ... In scanning Fourier spectrometer optical and electric modulation of signal is used to avoid this problem, for static Fourier spectrometer there are no such ways. ...

Astronomical Data Center . ... You can access the files described here in three ways: . ... Use CDS' VizieR Service at ADC to explore the data files. ... Get the data files via anonymous FTP. ... 1981) -------------------------------------------------------------------------------- Byte-per-byte Description of file : table1a Byte-per-byte Description of file : table1b -------------------------------------------------------------------------------- Bytes Format Units Label Explanations ...

... Mokhovaya st., 11, Moscow, 103907, Russia. ... Proceedings of ECCTD’01 -European Conference on Circuit Theory and Design, . ... An approach to design of chaotic oscillators with preassigned spectral characteristics is proposed and its practical realization is demonstrated. The basic idea of the approach is to form a frequency-selective circuit and to connect it to a harmonic oscillator so as to provide generation of chaotic oscillations with given spectral characteristics. ...

... Obs., 1974, v.49, p.80-85. The sixty five radial velocity measurements of Cep C (blue visual companion of Cep A) have been obtained. The evidences are give that Cep C is spectral binary. The most probable periods of system are: 0 d ,89986 and 0 d ,46458 . In both cases the -velocity of Cep C is in good agreement with mean velocity of Cep A. It is a strong argument on their physical connection. The secondary component of Cep C may have very low mass (near 0.1 solar mass or less). ...