... We demonstrate through numerical simulations that model parameters estimated with our technique are essentially bias-free, even when the average number of counts per bin is 1. ... The IW technique avoids such biases by estimating through successive iterations, where for each iteration, j, , and the best-fit parameters are determined by minimization of . ... In our sample, we find that the minimum values and best-fit parameters converge after about 6 iterations. ...

A Test of Galaxy Evolutionary Models Via Angular Sizes M. Im S. Casertano, R. E. Griffiths, & K. U. Ratnatunga (The Johns Hopkins University) The relationship between angular size, magnitude, and redshift of faint galaxies is explored as a potential tool to distinguish between different galaxy evolutionary models. ... The mild lumi­ nosity evolution model predicts more luminous galaxies of large angular size at high redshift, as does a standard no evolution model. ... 25) with redshift higher than z ? ...

The above image is a computer simulation of the distribution of mass in a Dark Matter dominated Universe. ... Structure (\eg density enhancements) clearly forms at the intersection of these filaments. ... What is Dark Matter? ... Testing for the presence of dark matter in the solar neighborhood now becomes an accounting problem The possible sources of this mass in the solar neighborhood are 1) luminous stars, 2) interstellar gas, 3) stellar remnants (mostly white dwarfs) and 4) dark matter: . ...

... Scheming arXiv:astro-ph abstracts almost an year never offered me an occasion that the fit of the Poisson distribution is tested in different ways, instead it is taken for granted by plugging data and (source) model into a (modified) ? ... Abstract: goodness-of-fit tests based on the Cramer-von Mises statistics are given for the Poisson distribution. ... 2 statistic for testing the goodness of fit in astronomy and this D statistics is considered as a two sided test approximately distributed as a ? ...

. Next: Some statistical trends and Up: Spectral survey of Case Previous: Quasar CG 273 . љ . Some statistical trends and distributions . Sky and redshift distribution . Accuracy of data, comparison with independent measurements . root . 1/10/1998

... Space-time distribution of matter at the epoch Z=0.4--3.5 by analysis of absorbtion systems in QSO spectra" . A statistical analysis of distributions of C IV and Mg II absorption-line systems observed in QSO spectra within the cosmological redshift interval Z abs =0.2-3.2 is presented. ... The isotropy (or anisotropy) of the distribution is verified by comparing of independent distributions of the absorption systems in opposite hemispheres with their various orientations. ...

A comparative study of type I and type II supernovae . ... Sternberg State Astronomical Institute, Moscow, U.S.S.R. (Received 26 November, 1985) . ... No significant difference between SNe I and SNe II has been found in their radial distribution and frequency of outbursts in spiral galaxies. ... The radial distribution of type Ia SNe in spiral galaxies is only slightly steeper than the one for SNe II, while SNe Ib/c are more concentrated towards the central regions. ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...

... The distribution of redshifts among the DXRBS FSRQs identified so far (Figure 3) is quite similar to that of the 1 Jy and S4 samples. ... A more thorough comparison will have to await completion of our survey and the convolution of the redshift distribution with the WGACAT sky coverage. As has already been mentioned by Hook et al. (1996), selecting flat-spectrum sources is an efficient way of finding high-redshift, radio-loud quasars. ...

... Within SAS, a tool is available to check the pile-up fraction in the pn data: epatplot . This tool compares the observed pattern distributions (derived from a pn calibrated and concatenated even list) with the calibrated models. ... The lower panel is the key element for the evaluation of the pile-up fraction: it shows the observed distribution of pattern as a function of energy (PI channel in Analog-Digital Units ), using the same color code. ... Pages maintained by SAS librarian . ...

... Galaxies rotate and move in clusters as if a tremendous amount of unseen matter is present. But does dark matter exist in the greater universe too -- and if so, where? ... In the above frame from a computer simulation of our universe , a 300 million light-year slice shows dark matter in gray and galaxies as colored circles. ... Publications with keywords: universe - dark matter - 2dF survey - simulation . Publications with words: universe - dark matter - 2dF survey - simulation . ...

. You can display the line by line difference between two files with the diff command. diff file1 file2 . The information given by the command tells you what changes need to be made for file1 and file2 to match. If there is no difference between the files you are returned to the shell prompt . diff indicates which lines need be added ( a ), deleted ( d ) or changed ( c ). Lines in file1 are identified with a ( < ) symbol: lines in file2 with a ( > ) symbol. Examples . Did You Know? .

Next: SMUDGES Up: Minutes of the 1st Previous: Pilot Survey . ... The Jodrell Virgo survey is part of HIJASS and encompasses 4 X 8 degrees, fully sampled. ... This indicates that we should perhaps survey the outskirts of the cluster to look for low mass clouds. In the survey, objects were detected using a combination of by-eye method and automated routine. 28 detections of well known galaxies . ... Velocity distribution suggests infall or extension along the line of sight. ... Jon . ...

... 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...

... Summary. ... Subject of my Ph.D. thesis is the analysis and interpretation of the overall gas dynamics in the starburst galaxy NGC 1808, in comparison with other spiral galaxies in a similar evolutionary stage. ... c) nuclear outflow of neutral gas into the halo of the galaxy, . ... We have mapped the 21-cm absorption in the nuclear region of the starburst galaxy NGC 1808 using the VLA AnB-hybrid array with a resolution of approx. 5.2 arcsec (which corresponds to 275 pc). ...

Neptunes in the Noise: Improved Precision in Exoplanet Transit Detection AimИe Hall , Simon Hodgkin , Gabor Kovacs and Don Pollacco 1 1 1 1 2 Institute of Astronomy, University of Cambridge 2 Department of Physics, University of Warwick Figure 2 (right): Distribution of radii of all known exoplanets (grey), with those from Kepler (green) and SuperWASP (blue) also shown. We present early results from a new analysis of raw data taken with the SuperWASP telescope[1]. ...

... The areas between the contours were measured automatically. The results of the measurement are represented on fig.1 The graphic shows the distribution of the height levels against their areas. ... USGS, USA Fig.1 The dependence of the distribution of the heights levels versus the area occupied Fig.2 The distribution of the areas of heights levels in the northern and southern hemispheres Fig.3 The distributions of the areas heights levels in eastern and western hemispheres of Mars ...

... In this case the F5-F9 dwarfs turn out to be more metal-rich (by 0.1 in [Fe/H] ) thab G and K dwarfs, and the metallicity of the Hyades cluster turns out to be larger than the solar one [Fe/H] Hyades =+0.1 . ... При этом карлики F5-F9 оказываются богаче металлами, чем более поздние звезды, примерно на 0.1 по [Fe/H] , и металличность звезд Гиад относительно Солнца равна [Fe/H] Hyades =+0.1 . ...

Variations of total ozone content and lower ozone stratosphere temperature in Antarctic Region during winter-spring period A.V. Grytsai National Taras Shevchenko University of Kyiv Astronomy and Space Physics Department assen@univ.kiev.ua Data, used in the work work Total ozone: Total Ozone Mapping Spectrometer (TOMS) measurements during 1979 - 2005 and Ozone Monitoring Instrument (OMI) ones for 2006, for http://toms.gsfc.nasa.gov/ftpdata.html. ... A long-term TOC decrease is significant. ...

... The dayside auroral precipitation consist of magnetosheath related boundary layer precipitation, and plasma sheet related BPS/CPS precipitation (extensions of the nightside precipitation regions). ... For example, the much lower fluxes from the LLBL region when compared to the cusp are compensated by the bidirectional electron beams found in the LLBL: the precipitating energy fluxes in the LLBL and the cusp are not that different. ... directly through the cusp and plasma mantle . ...