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. ...

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 . ...

Marc White . ... Turbulent entrainment processes may play an important role in the outflows from young stellar objects at all stages of their evolution. In particular, lateral entrainment of ambient material by high-velocity, well-collimated protostellar jets may be the cause of the multiple emission-line velocity components observed in the microjet-scale outflows driven by classical T Tauri stars. ... University of Amsterdam; STARPLAN, Copenhagen, Jul 2013 . ... E marc.white@anu.edu.au . ...

... Bojan Nikolic web pages (r. 329) . ... We present a Bayesian approach to calculating the coefficients that convert the outputs of ALMA 183 GHz water-vapour radiometers into estimates of path fluctuations that can be used to correct the observed interferometric visibilities. ... Inference of Coefficients for Use in Phase Correction . ... Simulating Atmospheric Phase Errors, Phase Correction and the Impact on ALMA Science . ... Copyright 2005 -- 2016, Bojan Nikolic feedback welcome ...

HST Call for Proposals and HST Primer for Cycle 24 . ... Hubble Space Telescope Primer for Cycle 24 > Chapter 6: Orbit Calculation for a Phase I Proposal > 6.1 Overview of an Observing Program . ... Definitions (HST Orbits, Orbital Visibility Periods, and Visits) . ... See Section 3.2 for details on telescope guiding. ... Lay out all the exposure and overhead times for the program into visits (described in Section 6.5 ) and add up the number of orbits from each visit to obtain the total orbit request. ...

XMM-Newton CCF Release Note XMM- CCF -REL-176 RGS QUANTUMEF Shortest-Wavelength Correction Factors A.M.T. Pollock July 27, 2004 1 CCF components Name of CCF VALDATE List of Blocks changed XSCS ag RGS1 QUANTUMEF 0013 1998-01-01T00:00:00 RGA EFFAREACORR NO SI1 SI2 SI3 SI4 SI7 RGS2 QUANTUMEF 0014 1998-01-01T00:00:00 RGA EFFAREACORR NO SI1 SI2 SI3 SI4 SI5 SI7 2 Changes Near the short-wavelength end of the RGS bandpass, the instrument ... The best- t power-law indices, , are shown. ...

... The HST uses an onboard model of its orbit to perform in real-time various control functions relating to spacecraft operations and observation support. ... New coefficients for the ephemeris are updated every other day, and are archived as FITS keywords for each HST observation data set. Using these coefficients,an observer can perform a variety of calibration and characterization calculations relating to the orbital position and velocity of the telescope. ...

... This thesis sets out to explain this observation by the presence of optical non-thermal synchrotron emission, connected with the relativistic jet that powers the radio emission in these quasars. ... We find that about 40% of the sources have power-law SEDs, while a similar number show evidence for two primary components: a blue power law and optical synchrotron emission. The blue power law is similar to the dominant component observed in the spectra of optically-selected QSOs. ...

Next: Extinction efficiencies: general behaviour Up: Optical properties of cosmic Previous: Optical properties of cosmic . It is now evident that observed interstellar extinction cannot be explain using particles of only one kind. ... The intensity of radiation after passing a dust cloud is equal to . ... The interstellar extinction is . ... Next: Extinction efficiencies: general behaviour Up: Optical properties of cosmic Previous: Optical properties of cosmic root 2003-04-09 ...

Irregular phenomena in the Earth Pole oscillation process and temporal variations of geopotential Valery Bondarenko, Vadim Perepelkin s The observed irregular phenomena in the Earth Pole oscillation process are very variety. ... These phenomena indicated in the IERS data are the "abnormal" fluctuation of the Earth Pole coordinates which owing to changing of the geodynamical parameters gives negative result in interpolation and forecast of the first approximation mathematical model. ... Fig. ...

... We will consider the rms, (K), for observations with a receiver of system temperature, T , frequency resolution, per polarization, and total integration time per observing cycle, . ... For ``in-band'' frequency switching, the line under investigation is always in the observing band. ... Position Switching or ``Out-of-Band'' Frequency Switching: Here the line is only observed for one half of the time, with noise being present all of the time. ...

... Several years ago, John Butler and myself derived the radiative energy output from the `quiet' corona of some twenty odd stars, similar in many ways to our own Sun, and found that there was a one-to-one correspondence with the total amount of energy radiated during flares on these stars over a period of say one day. ... The velocities derived increase from 0 km/s at 20,000K to a red-shift of 10 km/s at 190,000 K for the quiet Sun, and to 15 km/s 100,000 K for the active region. ...

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. ...

... Our scientific interest is an accuracy of asteroid CCD observations obtained by amateurs and professional astronomers all over in the World. ... These data help us to analyse an accuracy of real CCD positions in the MPC Database. ... Do you test your observations of the small Solar System bodies permanently before sending them to the International Minor Planets' Center? ... Do you know a real accuracy of your positional CCD-observations in comparison with the other observatories' one ? ...

... Optical depth at 100 MHz 122-127 F6.4 --- e_Tau ? ... The highest absorption is observed in the direction of G0.0+0.0. ... G0.9+0.1 is a classic example of a composite, two-component SNR including an extended (8') source with a steep (a=-0.64) spectrum and a central, more compact, component (2') with a flat spectrum (a=-0.1) [49]. ... The highest absorption was observed for four sources in the direction of the galactic central region: 1, 2, 3, and the unidentified source G0.4+0.1 [t(100MHz)=6-0.8]. ...

Abstract -- Calculations are performed for the linear polarization of starlight due to extinction by aligned dust grains when the starlight traverses a medium with irregular magnetic fields. This medium is intended to represent the optically thick components of interstellar clouds which are observed to make little, if any, contribution to the polarization of starlight. ...

... Here some data observed on the 6m telescope with IFP installed in the OLD focal reducer are presented. ... Mkn 3: velocity field . ... NGC 5252: [OIII] image . ... NGC 5252 was observed 23 Feb. 1998 in the [OIII]5007 emission line with CCD TK1024 as detector. ... We observed the ionized gas velocity fields of the spiral galaxies with two purpose. ... Restored velocity field of NGC 157 in the reference frame rotating with the pattern speed overlaid on the Ha image of the galaxy . ... NGC 4100 . ...

... A radio galaxy is a galaxy that emits an unusually big amount of energy at radio wavelengths. ... Inside of each galaxy with an active nucleus (radio galaxies are among them) there must be a system of a "central machine" responsible for the colossal amount of the emitted energy from radio to gamma ranges. ... Sometimes a radio source in an active galaxy may flare again if the needed conditions appear (a new portion of matter would fall into the furnace of the "central machine"). ...

... 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. ...

... Archives . ... The PCA and ICA is used for separating mixed components with some assumptions. ... The need of source separation methods in astronomy has led various adaptations of decomposition methods available. ... I rarely come up with a paper which gathered and summarized component separation methods applicable to astronomical data. In that regards, the following paper seems useful to overview methods of reducing dimensionality for astronomers. [arxiv:0805.0269] . ... Chandra Blog . ...