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. ...

Next: Prior Models Up: Prior Models and the Previous: Bayesian Paradigm . The observed image differs from the true brightness distribution in having been blurred and encountering statistical noise in the recording process. ... Let us describe the noise models. ... This model can be approximated, at least for high brightness values, by the Gaussian distribution . ... The noise model we will use in this paper is Poissonian; see Molina and Ripley (1989) for the use of robust Gaussian noise models. ...

... Mosaicing may be used in aperture synthesis to map large fields of view. ... A CLEAN-based method has been developed, in which the components are located in a modified expression. ... Mosaics . ... We present here a CLEAN-based method for the mosaic deconvolution. ... This is a basic problem in mosaic deconvolution: if we intend to apply CLEAN on , the risk of taking a noise peak as a CLEAN component is too important. ... A new CLEAN-based algorithm for mosaic deconvolution has been developed. ...

The problem of solar wind data correlation for the observations onboard several spacecraft is very important for three points of view: . ... This problem is studied now in detail by systematic determination of ion flux and ion velocity data correlations by INTERBALL-1 (IKI group), WIND and IMP 8 (both - MIT group). ... Solar wind plasma correlation lengths from IMP 8, WIND and INTERBALL-1. ... Correlation of solar wind observations onboard several spacecraft: INTERBALL-1, IMP 8 and WIND data. ...

... Current APO Weather . ... Search Site . ... Information for New Users . ... Technical Staff pages . Night Logs and Mailing Lists (maintained by APO) . ... Technical Documents and Database Search . ... Observer's Documentation and Procedures . ... Problem Reporting and APO Technical Documents Database Search . ... APO Drawing/Document Management Procedures . ... APO Technical Documents Database Search . Home Astrophysical Research Consortium . ... Mail Lists (maintained by APO) . ...

Next: Information on planets Up: Practical loading and calibration Previous: Bandpass and antenna gain . The best task to correct the flux scale of an observation is mfboot - mfboot performs an analagous function to gpboot . ... It works by scaling the antenna gain table so that the flux density scale of the observed data agrees with some model. ... Task mfboot can also be used when bootstrapping from a point source. ... MFBOOT . ... Select flux density calibrator. ...

... The R , I photometric observations of SBS 0335-052W were obtained occasionally during the study of SBS 0335-052 with the 3.5m telescope in Calar Alto on 1991 October 6. ... Aperture photometry was performed on the standard star observations using MAGNITUDE/CIRCLE task with the same aperture for all stars. ... For photometry of extended objects, we used the package SURFPHOT as well as dedicated software for adaptive filtering developed at the Astrophysical Institute of Potsdam (Lorenz et al. ...

... High spectral, spatial and temporal resolution UV observations of the quiet Sun transition region show a highly structured and dynamical environment where transient supersonic flows are commonly observed. ... Estimates of the kinetic and enthalpy fluxes associated with these events show that explosive events are not important so far as solar coronal heating is concerned. ... In some cases, non-Gaussian line profiles are associated with supersonic flows in small magnetic loops. ...

... 2.3 Establishing the Extragalactic Distance Scale . ... 2.3.2 The Second Rung: Distances to stellar clusters . ... 2.3.4 Distances to Local Group Galaxies . ... The Luminosity Function of Planetary Nebulae . ... 3.2.2 Clusters of Galaxies . ... 4.2 Evidence for Dark Matter as a Function of Scale Size . ... 4.3 Other Dark Matter Indicators for Galaxies . ... What is the nature of the large-scale distribution of matter in the universe as traced by the three-dimensional galaxy distribution? ...

... Archives . ... Reduced and Processed Data . ... 2 distribution plays an incredibly important role in astronomical data analysis, but it is pretty much a black box to most astronomers. ... Comment ( RSS ) | ... I guess in the typical analysis we call chi2 a ?random variable? that follows the chi2 distribution: . ... where D(i) is the observed data, M(i) is the model predicted data and we ?silently? assume that D(i) is normally distributed and each i measurement is independent. ... Chandra Blog . ...

spaceweb@oulu.fi - last update: 20 September 1998, 2020 UT (RR) . Traveling Convection Vortex (TCV) is a name given to a specific type of daytime magnetic impulsive events observed by high-latitude ground-based magnetometer arrays. Since the most likely source for TCVs is the solar wind , they are considered to be important processes in transfering energy from the solar wind into the magnetosphere . ... For example, one AMPTE Lithium release in the solar wind caused a TCV event . ...

... Observations of the Moon eclipse on 17.09.97 have shown the Moon details contrasts had decreased and the total radio brightness had fallen at all observed frequency range (from 10% at 1.38 sm down to 2.5% at 13 sm). The fall of the Moon radio brightness has been detected during the eclipse at decemeter waves for the first time. ... Radio emission of the Copernicus crater at 1.38 and 2.7 sm has been detected for the first time. ...

... Star formation . ... The puzzling core of the Phoenix cluster: deep X-ray observations . ... SPT-CLJ2344-4243 shows a strong cool core with a potential mass deposition rate of ~3000 Msun/yr derived from the X-ray luminosity. ... The spectral analysis of the deep XMM-Newton observation of the Phoenix cluster found an average mass-deposition rate between 210 and 620 Msun/yr for the gas in the temperature range 0.15-3.0 keV (subject to calibration uncertainties). ...

Once students get the hang of it, they can find and measure the brightness of Delta Cephei in a few minutes. ... of Delta Cephei . ... Oct. ... The following table lists the measurements of Delta Cephei made by one amateur astronomer in autumn 1990. ... 4.0 . ... This activity is a simplified version of one that appeared in Hands-On Astrophysics, a series of activities prepared by the American Association of Variable Star Observers with support from the National Science Foundation. << previous page | ...

... 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 . ...

... Science . ... ESO Data . ... If you wish to interface GASGANO to VLT instrument pipeline recipes build on top of the ESO Common Pipeline Library (CPL) and the qfits library , you will have to download and use the specific instrument package available here . ... To use the latest Gasgano version (2.4.8), Java 7 must be available on your system. ... Type java -version on the command line to verify that the printed java version is 1.7.x. You MUST be under your $HOME directory to install GASGANO: . ...

... Previous: Determination of Variable Time Delay in Uneven Data Sets . ... It is shown that the likeness of the periodogram and the LS-spectrum (both estimators of the power spectrum are widely used in the spectral analysis of time series), depends on the properties of the spectral window corresponding to the distribution of time points. ... Present day theory and practice of the spectral analysis of unequally spaced time series are based on two approaches. ...

Next: NICMOS/HST H-band (F160W) Images Up: NICMOS Science Previous: HST NICMOS Observations of . ... Observations of P . ... The NICMOS team has devised a comprehensive program of observations of the Galactic Center. ... Data in hand give a first look at variability and a detailed look at the search for the tip of the main sequence will be discussed where NICMOS has demonstrated adequate sensitivity and photometric precision to identify likely O8-B1 stars at the Galactic Center. ...

... According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. ... The polar ring galaxies (PRGs) reveal external rings or disks of gas, dust and stars rotating in a plane roughly perpendicular to the disk of the central galaxy. ... The shape of the dark halo in the model was chosen so as to achieve the best fit to the observed rotation of both galaxies themselves and their polar rings. ... The SPRC-7 galaxy. ...

... The bright supernova (hereafter SN) in the galaxy NGC 4527 was first sighted by S. Knight (USA) on April 13.17UT at magnitude ~14.0v. The report of the sighting was subsequently forwarded by phone to the AAVSO. ... SN 1991T. The galaxy NGC 4527 is an Sb(s)II type galaxy with an apparent Blue magnitude of 11.32 (Shapley-Ames, 1981). ... An analysis of this event utilizing visual observations by amateurs, plus a light curve is presented.. ... THE LIGHT CURVE: . ... ISN SN 1991T web page . ...