Next: Background Definition Up: Echelle Spectra Previous: Order Definition . ... Their removal is a rather delicate step, because in high-contrast images (such as well-exposed echelle spectra) there is always a danger of damaging the scientific contents of the frame. Particle hits can be removed from scientific exposures by splitting the exposure and comparing spectra of the same target obtained under the same instrumental configuration. ... Note that the background has been subtracted already. ...

... 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? ...

... QSO spectra in the ROSAT band are steeper than the background at harder energies, and furthermore at fluxes below 1E-14 ergs/(s cmќ) the quasar source counts flatten off and are replaced by more numerous populations of relatively low red-shift objects, apparently Narrow Emission Line Galaxies (NELG). ... We extracted the luminosity function from ROSAT Deep Survey results, and extrapolated by a factor of 2 - 3 to account for changes expected in the harder XMM band. ...

... HST Overview . ... The FOC suffers from various types of background, the most important of which are thermal electrons, Cerenkov radiation from high energy particles, geocoronal emission lines, zodiacal light, and light scattered within HST from the bright Earth or Moon. ... From on-orbit measurements using the f /96 camera, the former background has been found to vary with solar zenith distance (ZD); see Sections 6.4, 6.5, and 7.0 of the FOC Instrument Handbook , version 7.0, for more details. ...

Next: Imaging by an Optimizing Method . ... A big advantage of this numerical integrator is its stability: the error in the semi-major axis and the eccentricity depends only on the step size and does not grow with an increasing number of time steps. ... As the integration time increases, the numerical results become more contaminated by various errors. ... A new symplectic integrator produces no secular truncation errors in the actions of a Hamiltonian system. ...

. Next: Finding periodic signals Up: Searches and surveys Previous: Searches and surveys . љ . Individual pulses detected for few pulsars . Detectability peaks new 400MHz for most . Typical sky background Jy . Typical pulsar flux few MJy . љ љ . Figure 9: Sensitivity of the Parkes survey . Jon Bell . Thu Dec 19 15:15:11 GMT 1996

Disastrous earthquakes happen 100 to 200 times a year. ... There is a chance that the data of ionospheric plasma observations hold an answer to the latter question. Satellites and ground-based facilities may detect earthquake precursors in the ionosphere a few hours or days before the main shock. ... ULF "Hz"-oscillations have been recorded several hours before the main shock in a narrow magnetic field tube (40...100 km along the satellite trajectory) conjugated with epicenter of the earthquake. ...

... The Australian National University] [Department of Physics] [Paul Francis] [Main Roleplay Page] . These exercises are my attempt to adapt the technique of Problem Based Learning to the context of introductory astronomy and astrophysics classes. ... As students grapple with the puzzle, they are forced to learn the subject matter of the course. ... This exercise is designed for 1st year University students with a reasonable high-school background in Maths and Physics. ...

There are stopped jobs. You have started a job by issuing a command and have then "stopped" the command from executing and placed it in the background using the key sequence Ctrl-z . Start the job again by typing fg and pressing the <Return> key. Quit the job or wait until it has finished. Try to logout again. Example . If you have several stopped jobs, you will have to go through this procedure for each one before you are able to logout. Not login shell. ...

C C C C C C lass lass lass lass lass lass 1 2 3 4 5 6 Introduction, Background Solar System Stars Galaxies Cosmology Special Topics Class 1 Introduction, Background History of Modern Astronomy The Night Sky, Eclipses and the Seasons Kepler's Laws Newtonian Gravity General Relativity Matter and Light T lescopes e 1. ... Kirchoff's Laws trum Emission Line Spectrum 2. A low-density, hot gas emits light whose spectrum consists of a series of bright emission lines. ... Absorption Spectrum 3. ...

... Moscow, Russia E-mail: krivosheev@iki.rssi.ru Notes: · · The Monte Carlo method (s) is also called the statistical test method An innumerable number of processes can be listed the outcome of which is not determined and has probabilistic nature, but these processes obey statistical laws, so to obtain the result we have to make multiple similar tests, i.e. to use the MC method Because probabilistic processes are widely spread in nature, the MC ...

... Epistemology is a part of the study of Philosophy dealing with how we use our senses to know something about the world. ... Yet we know that we can be deceived by our senses. ... If we cannot always trust our senses, how can we ever know anything for certain about the world? ... A branch of epistemology that has come into vogue in the last 10-15 years is the problem of consciousness. ... What relationship is there between our conscious experience and the true nature of the physical world? ...

... December 21, 1997 . ... Advantages are briefly discussed of gaining in spectral resolution, which is accompanied by losses in signal level, as compared with the attempts to improve the accuracy of measurement of line parameters by means of rising the S/N ratio alone with increasing the exposure time. To partially solve the problem of observations of faint objects at the BTA a new design echelle spectrometer is proposed. high resolution spectroscopy . ...

... Posts tagged ?X-ray? ... Posted by vlk . There is a lesson that statisticians, especially of the Bayesian persuasion, have been hammering into our skulls for ages: do not subtract background. ... 6 Comments . ... Algorithms arXiv Astro Bad AstroStat Bayesian CHASC Cross-Cultural Data Processing Fitting Frequentist Galaxies gamma-ray High-Energy Imaging Jargon Job Languages MC MCMC Meta Methods Misc News Nuggets Objects Optical Physics Quotes Spectral Stars Stat Timing Uncertainty X-ray . ...

... R.A. = 00h55m04s.86, Decl. = -37 41'43".7 . ... Variable star in NGC 1511 . ... Variable star near Pegasus 2001bn IAUC 8624 BV anon 2001bh 7622 K star ugc11635 2001dh 7482 M star ic5374 1999db 7227 QSO anon 1999dc 7227 AGN anon 1999cx 7210 AGN anon 1999cu 7210 AGN anon 1999bs 7141 cat var ugc11093 1998di 6982 dwarf nova anon 1993U 5818 QSO anon 1993V 5818 QSO anon 1992W 5517 M star mcg 8-23-96 1992X 5517 M star mcg 6-32-24 1991ap 5327 QSO anon 1989Z 5162 var ngc4013 1985J 4059 CV ugc6274 ? ...

Recursive solution of light scattering problem for multi-layered axisymmetric particles V.G.Farafonov St.Petersburg University of Aerocosmic Instrumentation St.Petersburg, 190000, Russia and V.B.Il'in Astronomical Institute, St.Petersburg University, St.Petersburg, 198504, Russia ABSTRACT Light scattering by inhomogeneous (layered) particles is the problem that often arises in optics of the atmosphere and ocean, biophysics, astrophysics, etc [1]. ... Farafonov V.G., Il'in V.B. (2000) Opt. ...

... Dr. Ravil Nazirov is the head of the workshop, and Andrew Ananjev is the secretary of the workshop. ... The workshop is used to be held in the last decade of the month, preferably on Tuesdays. ... The next session will take place October 29, 1996 . ... There is "CONPAS" mailing list which you can join to discuss issues of problem solving and to be automatically notified of important dates and decisions with respect to the coming sessions. ... Secretary of the Workshop: Andrew Ananjev . ...

Project P1979 (snezana and joel) were doing HI absorption on pulsars using 9 level sampling and folding mode with the wapps dumping acfs. ... If you are storing acf's, then the data is written to disc after step 4. ... Idl routines (written by me) are able to read pulsar wapp acf data and do the kulkarni/heiles 3 level correction and murray lewis's 9 level correction (actually the 9 level idl code was written to find this problem and is probably not in the production library yet.. ...

Next: Initial conditions Up: Old neutron star distribution Previous: Introduction . The problem to be solved is to find stationary space distribution of stars which have had certain initial space and velocity distributions and move in a given potential. ... In principle, the most straightforward way to obtain the solution is to integrate directly the equations of motion for a sufficiently large number of stars with different initial conditions. ... Then space density is given by . ...

... The Second International Astronomy Olympiad . ... Problems to solve, 8-10 Form Text of these problems is available in Russian too. ... Two stars have the same absolute magnitude. ... The orbital period of Mars is 687 days. ... See problem 2. for 8-10 Form. ... Problem to solve, 9-12 Form Text of the problem is available in Russian too. ... Problem is about Doppler-effect, to find velosities of two stars using their spectra and spectrum of our Sun, to estimate speed of the Earth moving around the Sun...