... ACS Instrument Handbook . ... Advanced Camera for Surveys Instrument Handbook for Cycle 20 > Chapter 9: Exposure-Time Calculations > 9.3 Computing Exposure Times . ... Computing Exposure Times . ... Expected counts C from your source over some area. ... As a consequence, in order to obtain correct estimated count rates for red targets, observers are advised to use the synphot package in IRAF /STSDAS for which the proper integration of encircled energy over wavelength has now been incorporated. ...

... We have developed an integrated system that performs astronomical observations in Near Infrared bands operating two-dimensional instruments at the Italian National Infrared Facility's ARNICA and LONGSP . ... The user interface is organized as widget-based X11 client. ... 1993; Di Giacomo et al. 1993). ... Moreover, if the interprocess communication interface includes support for networking, the software immediately becomes network distributed software. ... DESQview/X User Guide 1993, Quarterdeck . ...

Next: Model Spectra for Spectral-Fitting Up: Spectral Analysis Previous: A Quick Look at . ... For ROSAT PSPC data, this conversion is done during the on-line (SASS) processing. For IPC observations, the instrument gain varies both across the detector and in time, and is applied during off-line processing (PROS) using the BAL histogram. By default, spectra are extracted in PI bins for PSPC data and in PHA bins for IPC data. ... Special techniques are required when using Einstein IPC data. ...

... Calculated exposure times do not take into account instrument and telescope overheads. ... The reference area for the S/N is circular with a radius equal to FWHM of the Image Quality PSF at the airmass and wavelength of observation. ... begin{equation} \mathit{FWHM}_{\text{IQ}} = \sqrt{\mathit{FWHM}_{\text{atm}}^2(\mathit{s},x,\lambda)+\mathit{FWHM}_{\text{tel}}^2(\mathit{D},\lambda)+\mathit{FWHM}_{\text{ins}}^2(\lambda)} \end{equation} } \) . ... The Exposure Time is the product of DIT and NDIT . ...

Next: Star Formation Rate and Up: No Title Previous: Calculation of Evolutionary Tracks . To start calculations, we choose the distributions of the initial binary parameters: the mass of the primary ZAMS component, , binary mass ratio, , orbital separation a . ... whereas the mass ratio distribution is not. ... The zero assumption often made is that the mass ratio distribution has a flat shape, that is binaries with a high mass ratio occur as frequently as those with equal masses. ...

XMM­Newton CCF Release Note XMM­CCF­REL­no­number­assigned EPIC Spectral Response Distribution R. D. Saxton 27 Feb 2002 1 CCF components Name of CCF VALDATE CAL VERSION XSCS flag EMOS1 QUANTUMEF 0010.CCF 2000­01­01 NO EMOS2 QUANTUMEF 0010.CCF 2000­01­01 NO EPN QUANTUMEF 0010.CCF 2000­01­01 NO 2 Changes Four new extensions, FRACTION CHANNEL, FRACTION ENERGY, QE TOTAL and EBINS FRACTION have been added. ... EBINS FRACTION ENERGY: The energies used to define the QE TOTAL array. ...

... Galaxies 99 Cosmic background with model of cloudy interstellar medium Yu. ... Figure 1: Averaged spectrum of the cosmic background I f in frequency range 0.25 200 MHz for the Galactic poles. ... First interpretation of the cosmic noise background spectrum at broad band frequency range 0.25 200 MHz with a model of the cloudy interstellar medium ISM is presented here. ... Synthesized background spectra I f for regions of the Galactic poles at the frequency range 0.25 200 MHz is presented in Fig. ...

... There are compelling reasons for the pulsar community to utilise a standard data storage format. For example, standardisation of file formats significantly decreases the amount of effort required to integrate new instruments into the analysis chain. ... Accordingly, we have defined PSRFITS as a standard FITS-based format for pulsar data files. ... For example, the first line of Processing History HDU contains information about the data acquisition program and the initial structure of the file. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

... Ciel Espace, le magazine qui vous guide toujours plus loin . ... des pages consacr†йes †а la publication de vos photos Mais c'est aussi une vraie communaut†й avec laquelle partager votre passion et nourrir votre curiosit†й. Accueil Mati†иre noire : une observation d†йfie les astronomes . ... A la une . ... En effet, selon les mod†иles th†йoriques, les concentrations de mati†иre noire sont les lieux o†µ naissent les galaxies. ... Une mati†иre noire au comportement ordinaire ? ... Etat du ciel . ...

... The SMS program is a critical endeavor to investigate whether the predictions of standard cold dark matter cosmology are consistent with the observed matter distribution in the Milky Way halo. It is the deepest, most extended search for optically elusive dwarf satellite galaxies and tidal streams to date, covering the entire Southern hemisphere. ... However only a few dwarf satellites have been found around the Milky Way to date - 22 dwarfs compared to 500-10,000 predicted by theory (Klypin et al. ...

Twilight observations with MASS/DIMM B. Safonov Sternberg Astronomical Institute Moscow State University Comprehensive Characterization of Astronomical Sites, 2010 B. Safonov (Moscow State University) Twilight observations with MASS/DIMM SITE 2010 1 / 17 Why observe in twilight with MASS/DIMM? ... ASM includes 3 devices sensitive to background: guider, DIMM and MASS. B. Safonov (Moscow State University) Twilight observations with MASS/DIMM SITE 2010 2 / 17 Background in guider. ...

... Maps of 21cm emission are dominated by warm H i, and most observations of H i absorption against continuum sources are limited to discrete points. ... Current Results At right are maps of H i emission, HISA, and 12 CO emission in the eastern 25% of the survey, given as projections along the velocity (Figure 1) and latitude (Figure 2) axes. ... 2000, A. J., submitted Figure 1: H i Survey Map (`; b): H i 21cm brightness integrated over all velocity channels; white is bright and black is faint. ...

... 1Becker A catalog of 53522 4.85 GHz sources between 0 and 75^o declination has been generated from observation taken with the NRAO Green Bank 300 foot (91m) telescope. The flux limit of the catalog is dependent on confidence radius of ~50". Spectral indices have been calculated for 29051 sources which have counterpart in the Texas 365 MHz northern sky survey. ... The rms noise in the images varied from 5 to 8 mJy. The images has an angular resolution of ~3.5'. ...

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. ...

... AMPLE (Adaptable Minor Planet Ephemerides) is integrated software package to deal with a number of problems concerning minor planets with the aid of IBM-type personal computer. ... compiling a list of all numbered minor planets which can be seen at certain moment within specified sky region and visualization of their mutual positions; . ... As AMPLE is able to reproduce virtually any table of "the Ephemerides of Minor Planets" , it may be considered as computer version of the EMP. ...

APO/GIFS Instrument Factsheet The Goddard imager and Integral Field Spectrograph (GIFS) has recently been commissioned on the APO 3.5 m telescope. This factsheet presents a high level overview of the GIFS instrument. ... GIFS Imaging The GIFS imaging mode is used for imaging science and target acquisition for the IFS mode. ... Imaging Mode pixel scale: 0.168"/pixel · Comparison to Other APO 3.5m instruments: The GIFS field of view is smaller than SPICAM, but the filter set is far more extensive. ...

... Dept. for Physics of Stars&Galaxies . ... Astronomical Calendar . ... History of MAO . ... БЂ“ 2013. ... Zakhozhay O. and Vorobyov E.I. The signatures of disk fragmentation in spectral energy distributions // Proceedings of the conference Hot Planets and Cool Stars, Garching, November 12-16, 2012. ... Zakhozhay O.V., Vorobyov E.I. Spectral energy distributions of fragmenting protostellar disks // Formation, detection, and characterization of extrasolar habitable planets Proceedings IAU Symposium No....

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... AIA 304 ? ... bottom) images (colour table reversed) of a coronal hole region at the South Pole taken on 14 May 2010. ... In the present work we derive a Differential Emission Measure (DEM) distribution from a region dominated by spicules. ... This distribution is then used to study the thermal properties of the emission contributing to the 171 ? ... From our off-limb DEM we found that the radiance in the AIA 171 ? ...