... Spectral Filters . Quantum Efficiency and Exposure Limits . ... Which Instrument to Use: WFPC2, ACS, NICMOS, or STIS? Comparison of WFPC2 and ACS . Comparison of WFPC2 and NICMOS . Comparison of WFPC2 and STIS . History of WFPC2 . ... WFPC2 . ... What's New in Version 5.0 for Cycle 10 . ... WFPC2 Handbook on the WWW . ... Calibration Channel . ... LRF Photometric Calibration . ... Sources of Dark Current . ... Calibration Plan Summary . Cycle 4 Calibration Plan . ...

... Exposure Time Calculator (ETC) . ... ESO - Public Surveys . ... the recommended values to use for DIT, . ... Detector on-chip integration (DIT): seconds. to your chosen value - a separate page gives recommended values to use for DIT - for modes 1 and 2 below you may wish to start with the maximum recommended values as these will minimize the effect of read noise (a total object exposure of Y secs with DIT=X secs will produce Y/X lots of read noise) and give you a lower limit on the time needed. ...

An unbiased assessment of EPIC-pn Burst mode calibration Stefania Carpano 2012 EPIC BOC meeting, Leicester Tasks: Define the optimal calibration sample, by systematically analysing the whole XMM archive Assess the energy reconstruction accuracy in burst mode through comparison of spectra with theoretical models exposures taken in other EPIC-pn modes simultaneous obser vations with other payloads Estimate the impact of X-ray ...

... Up: Iraf Packages . ... IRAF Group, NOAO 1 , PO Box 26732, Tucson, AZ 85726 . This paper describes a new IRAF spectroscopy exposure time calculator. ... SPTIME takes an input source spectrum, either a reference blackbody, power law, or a user spectrum, a background ``sky'', observing parameters such as exposure time, central wavelength, seeing, airmass, and moon phase, instrument parameters such as aperture sizes and detector binning, a description of the spectrograph, and desired output. ...

We would like to announce the release of Version 2.0 of the CHIANTI database for astrophysical spectroscopy. The additions and corrections to the database have been described in a paper `CHIANTI - an atomic database for emission lines, III - Continuum radiation and extension of the ion database' by E. Landi, M. Landini, K.P. Dere, P.R. Young, H.E. Mason and has been published in Astronomy and Astrophysics Supplement Series, 135, 339 ,1999, (Paper III). ... Beryllium sequence . ... Boron sequence . ...

... The principles, methods, selection procedures and first follow-up spectroscopy results of the Hamburg/SAO survey described in the previous sections are intended to create a new large and deep sample of BCGs. ... However, the overall detection efficiency of emission-line objects is rather low for this first sample (about 31 %). ... The fraction of BCGs (as our main goal) among all emission-line objects is 63 % (47 BCGs among 74 in total). ... This is reflected by the statistics of all detected ELGs. ...

Optical and UV Spectrophotometric Standard Stars . ... A group headed by R. Bohlin at STScI have established a set of four white dwarf standards based on comparison of White Dwarf model atmospheres with HST FOS spectra. ... Extension of the white dwarf primary standards to more stars, giving 27 in total, are described in Bohlin (Proceedings of STScI HST Calibration Workshop, eds. A. Koratkar & C. Leitherer, p. 49, 1994) and in Bohlin (AJ, 111, 1743, 1996) . ...

... Bojan Nikolic web pages home . Next: Fitting of models of radio spectra --.. ... I describe an approach to fitting and comparison of radio spectra based . on Bayesian analysis and realised using a new implementation of the . ... used maximum-likelihood fitting of radio spectra by allowing objective . ... implementation details of the computer code. ... overall approach described here may also be useful for analysis of other . ... Copyright 2012, Bojan Nikolic feedback welcome ...

THE PARAMETERS INVOLVED IN HAPKE'S MODEL FOR ESTIMATION OF THE COMPOSITION OF THE EJECTA LUNAR TERRAINS. ... In the previous papers we were estimated the surface roughness of the ejecta lunar terrains by means comparison of the local phase function and the average integrated lunar indicatrix. ... The Hapke's theoretical model of the lunar surface reflection. ... For THE PARAMETERS INVOLVED IN HAPKE'S MODEL: S.G. Pugacheva, V.V. Shevchenko a low-albedo lunar surface parameter Bo = 1. ...

... Higher Criticism Statistic: Theory and Applications in Cosmology and Astronomy [.pdf] . ... pdf ] . ... Fitting Narrow Emission Lines in X-ray Spectra [.pdf] . ... A Convex Hull Peeling Depth Approach to Nonparametric Massive Multivariate Data Analysis with Applications . Abstract: We explore the convex hull peeling process to develop empirical tools for statistical inferences on multivariate massive data. ... We define the convex hull peeling depth, which enables to order multivariate data. ...

Next: Radial velocity of the Up: Optical spectrum of IRAS04296 Previous: Observations and spectra reduction . ... However, molecular emission features are only very rarely observed in the optical spectra of PPNe. ... On the other hand, it is well known that cometary nuclei spectra show prominent Swan band emission. In both spectra of IRAS04296 we have discovered strong emission in the (0;0) and (0;1) bands of the Swan system of the molecule. ... Now consider the case of IRAS04296. ...

... To provide a detailed comparison between the performances of the MOPRA and SEST telescopes at frequencies of 85-113 GHz we have repeated part of the spectral survey of molecular absorption lines which was carried out by Greaves Nyman (1996) with the SEST 15-m telescope using SgrB2 as background source. ... 1-6 June and 15-19 August 1997, BW = 128 MHz, 256 channels, position switching . ... SEST Spectra . ... C 3 H 2 (2-1) . ... on-off . ... HCN(1-0) . ... USB . ... June 1, 1997: gtp_log , tsys_log ....

I/220 The HST Guide Star Catalog (Lasker+ 1992) ================================================================================ The Guide Star Catalog Version 1.1 - An all-sky astrometric and photometric catalog to support the operation of the Hubble Space Telescope The Guide Star Catalog Version 1.0 is described in a series of papers: I. Astronomical foundations and image processing Lasker B.M., Sturch C.R., McLean B.J., Russell J.L., Jenkner H., Shara M.M. =1990AJ.. ... Astrophys. ...

... The exposure time calculator consists of two pages. ... The exposure time calculator models the observation chain which includes the target spectral distribution, atmosphere parameters, instrument configuration, and detector setup. ... 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} } \) . ... Specify an exposure time per pixel, . ...

... An estimate the rotation period of cometary nuclei is important for understanding and describing the physical processes of the cometary activity. Unfortunately, the measurements of the rotation periods of the comet nucleus depend on the model assumptions and it is one of the main reasons for the scatter of the estimates given in various articles for a given comet. ... Right: the image of the comet 29P/Schwassmann-Wachmann 1 obtained at the 6-m telescope. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... This is the first in a series of papers in which we describe and report the analysis of a large survey of Herbig Ae/Be stars in circular spectropolarimetry. Using the ESPaDOnS and Narval high-resolution spectropolarimeters at the Canada-France-Hawaii and Bernard Lyot Telescopes, respectively, we have acquired 132 circularly-polarised spectra of 70 Herbig Ae/Be stars and Herbig candidates. ...

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 . ...

Here are six comparison images of the central nebula region from my 1998 AAS dissertation talk. ... Mid: Schmidt Bj (3600-5200 ) optical reflected starlight (folded scale). Bot: IRAS 100 ?m thermal emission (log scale). Right Side: Detailed HI 21cm line emission near the Pleiades, imaged by the 2 x 2 degree VLA-D survey (inset box); large-scale structure was mapped with the Green Bank 140-ft. telescope. ... These images compare the post-thesis extended VLA survey with other datasets. ...

... D.1 Grammar . ... D.3 Comparison of tokenization in CSS2 and CSS1 . This appendix is normative. ... STRING ] S* ]? ']' ; pseudo : ':' [ IDENT | ... LENGTH S* | ... return CDC;} ~= { return INCLUDES;} |= { return DASHMATCH;} { string } { return STRING ;} { ident } { return IDENT ;} # {name} { return HASH;} @import { return IMPORT_SYM;} @page { return PAGE_SYM;} @media { return MEDIA_SYM;} @font-face { return FONT_FACE_SYM;} @charset { return CHARSET_SYM;} @ { ...

... The large field size of UIT is ideal for studies of globular clusters. ... Very metal poor clusters are conducive for the formation of very hot horizontal branch stars which radiate most of that energy in the UV part of the spectrum. ... M31 is the nearest large spiral galaxy to us. ... These are small dwarf galaxies and NGC 205 is a bit unusual because it still has retained some gas for star formation despite its low mass. M33 is an actively star forming spiral galaxy in the local group. ...