... The accuracy to which you can trust the absolute flux calibration of your STIS spectroscopic data at slit center is limited by several factors including: . The accuracy of the absolute sensitivity calibration of the grating and central wavelength setting. ... The STIS spectrum of this star is then extracted over a standard aperture extraction box and the sensitivity required to return the known flux from the star is determined as a function of wavelength. ...

Next: Geometric Corrections Up: Raw to Calibrated Previous: Artifacts . ... The majority of modern detectors (e.g. CCD, diode--array or image tube) have a nearly linear response while photographic emulsions are strongly non--linear. Even for the `linear' detectors, a number of corrections must be included in the intensity calibration. ... A raw frame is then transformed to relative intensities by . ... Thus, the gaussian grain noise on emulsions becomes skewed through the intensity calibration. ...

... epiclccorr (epiclccorr-1.0.8) [?? ... epiclccorr will treat all these corrections individually, developing and designing specific algorithms to correct the Relative Corrections . GTIs correction will be calculated using the GTI extensions located in the time series file, if any. ... Exposure correction is the time inside each frame where the CCD is taking data correctly (no counting or MIP problems). ... This correction will be calculated using the Live Time and Frame Time values of each mode. ...

Federal Communications Commission (ix)(A) For a station authorized pursuant to § 73.215 or Sec. § 73.509, a showing that the root mean square (RMS) of the measured composite antenna pattern (encompassing both the horizontally and vertically polarized radiation components (in relative field)) is at least 85 percent of the RMS of the authorized composite directional antenna pattern (in relative field). ...

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. ...

... User Guide ] Task: mfcal Purpose: Multifrequency antenna and passband calibration. ... No default. This can (indeed should) contain multiple channels and spectral windows. ... Key: flux Three to five numbers, giving the source flux density, a reference frequency (in GHz) and the source spectral index parameters. ... Key: interval This gives one, two or three numbers, all in units of minutes, being used to determine the lengths of the antenna gain and passband calibration solution interval. ...

Next: DIRECT MASSES FOR BXCIR Up: EXTREME HELIUM STARS: PULSATION Previous: PULSATION PROPERTIES . As already indicated, V652Her is an important EHe star because its relatively short pulsation period and large amplitude pulsations allow its overall dimensions to be determined with high precision. ... Saio & Nomoto (1998) made the first successful models for the merger of two carbon-oxygen white dwarfs, and prompted Saio & Jeffery (2000) to attempt models for the merger of two helium white dwarfs. ...

... Determining the nominal roll angle for stable intervals . ... We found the necessary information in a file 'rh*.ao', which has a binary extension table for each obi. ... Unlike the question of determining the nominal roll angle, we know of no a priori indication of this problem (although the guide star configuration may be the cause, or at least associated with this condition): it is necessary to examine the source position for each obi. ... The guide star record is at the end of the 'anc file'. ...

This module provides support for dynamically configured mass virtual hosting . ... Source File: mod_vhost_alias.c . ... For simple name-based virtual hosts you might use the following directives in your server configuration file: UseCanonicalName Off VirtualDocumentRoot /usr/local/apache/vhosts/%0 . A request for http://www.example.com/directory/file.html will be satisfied by the file /usr/local/apache/vhosts/www.example.com/directory/file.html . ... Module: mod_vhost_alias . ...

... The file names' construction . The flight (m) stage's file set . ... the orbital data used for the flight operation monthly (m) long-term planning, . ... The orbital calculations are based on the initial orbital data determined by KIAM RAN using the orbital radio- measurement treatment. The determined initial orbital data are presented as a state vector (satellite position and velocity) in the J2000 reference. ... Accept the file with extension '.bgr', where the Moscow time (MT=UT+3h) is used. ...

... The choice of the spectrograph design (Fig.2) is determined by the quantity R, the overall dimensions of the PF cage and the restrictions on the rigidity of the structure of the device. ... As the camera's objective a fast 4-lens aplanat is used having a focal distance F cam =140 mm and a relative aperture of 1:1.8, the resolution at the centre is no less than 80 gr/mm, that over the field at a distance of 3 mm from the edge along the frame ( ) diagonal is 35 gr/mm. ...

... 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 . ...

... The processing of these associated images presents new challenges to the HST data processing pipelines, which heretofore operated only on single images. ... Stage 1 (CALNICA) calibrates individual exposures without information from other members of the association. ... Stage 2 of calibration (CALNICB) only operates on associated images that have previously gone through CALNICA processing, and creates combined images for each distinct (non-overlapping) pointing within the association. ...

THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE BY MEANS OF DIGITAL MODELS. ... The surface brightness of Mercury was measured Danjon (1933, 1949, 1953) and Harris (1961) in phase angle 3o-123o. The analysis of the various data of the integral photometric gives the results of determination of the main photometric constants for Mercury. ... THE PHOTOMETRIC RESEARCHS OF THE MERCURY'S SURFACE: S.G. Pugacheva The surface brightness of the Mercurian images was established on the geologic map Mercury. ...

The ESA/ESO Astronomy Exercise Series 2 . The Distance to Messier 100 as Determined by Cepheid Variable Stars . ... The small variations in distance to the individual Cepheid variable stars in the Cloud are negligible compared with the much larger distance to the SMC. ... In this way Cepheid variable stars can be used as one of the 'standard candles' in the Universe that act either as distance indicators themselves or can be used to calibrate (or set the zero point for) other distance indicators. ...

Term mixture regarding solar chemical composition refers to relative abundances of heavy elements. Abundances of hydrogen and helium cannot be determined reliably from observations, therefore concentration of these elements are not taken from observational data. ... Table contains only elements which are abundant enough to be included into opacity and equation of state computations. ... First "low-Z abundances" to be published were AGS05. ... 5.5 . ... 6.22 AG89 : Anders E., Grevesse N. 1989. ...

... A three-cell test section roughly representative of the primary mirror was provided for this test by the Steward Mirror Lab. ... Additionally, the tests are intended to determine relative airflow vs. pressure drop characteristics for each of the air flow patterns so the results can be evaluated both as a function of flow rate and of pressure drop along the flow path. ... The bottom (top as installed) was cut out so it could close the chamber for heating and be removed for the cooling tests. ...

... For more distant stars we must use other techniques. ... Hence if we see a distant galaxy and can pick out any cepheids lying within it, we can calculate its distance. ... Here then is another method to gauge the size of the Universe and there are yet more. volume at high enough temperature a nuclear fusion reaction sweeps across the white dwarf's surface and eventually we will see a spectacularly bright new star (hence nova) in our skies. ... Why is this relevant to the size of the Universe? ...

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... NASA Explanation: Where are these gas clouds going so quickly? High velocity clouds (HVCs) of gas have been seen for decades but their origins and destinations have remained mysterious. Recent measurements have now placed at least one of these clouds in the halo of our Milky Way Galaxy , while other measurements have determined the relative abundance of cloud elements. ... Publications with keywords: high velocity clouds - Milky Way . ... Our Galaxy in Stars, Gas, and Dust . ...