Observation Strategies . Saturation is a common problem for narrow band filter images of galaxy nuclei. Often the surface brightness of the emission line is estimated from ground-based images with 1" resolution; sometimes line fluxes are quoted for apertures several arcseconds in radius. However, at HST resolution, much of this flux may occur in a single unresolved spot at the galaxy nucleus, thus leading to saturated images. ...

... Let us first find out which way -- rise in spectral resolution with some loss in the S/N ratio or increase in the S/N ratio with a fixed spectral resolution -- is better for the purpose of reduction of equivalent width determination errors. ... N -- number of counts for 1 ? ... line equivalent width, . ... Thus if the spectral resolution is managed to be increased (i.e. to decrease )without loss in the number of counts falling at 1 ?, the equivalent width measurement error is then proportional to . ...

... ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope 20GHz Survey . ... Images . ... An Imaging Survey of the Northern Galactic H Emission with Arcminute Resolution . ... We present preliminary results from a high-resolution, high-sensitivity imaging survey of the northern galactic H emission. ... Our observations place stringent limits upon the contribution to the apparent microwave fluctuations from free-free emission in the galactic foreground...

... Flux density at 1 GHz (/Jy): 2720 . ... Optical: Fast knots and quasi-stationary flocculli, with many filaments at large radii, and NE `jet'. ... ADS . ... 1991, ApJ, 373, 146. ... NH 3 absorption and CO observations. ... 1995, ApJ, 440, 706. ... 1995, ApJ, 444, 244. gamma-ray observations. ... Anderson & Rudnick 1996, ApJ, 456, 234. ... 1999, ApJ, 518, 284. ... NRAO 12-m at 86 GHz (72": S=101?3.3 Jy) and 140 GHz (44": S=69.6?6.3 Jy), plus CO observations. ... 2001, ApJ, 547, L41. ...

... 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. ...

... We present 5GHz high resolution VLA observations of 2,127 radio-- and X-ray--emitting sources found in both the Green Bank (GB) 5GHz radio catalog and the ROSAT All-Sky Survey (RASS). We report core flux densities and positions accurate to =-0.5". ... This table has 1861 rows and 9 columns giving: Catalog source name, RA and DEC (J2000), observation code, S/N ratio, VLA core flux density at 5 GHz (mJy), Green Bank flux density at 5 GHz (mJy), error in Green Bank flux density (mJy), and Notes. ...

... 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. ...

... Aloisi, A. The Old Stellar Population . Alonso-Herrero, A. HST /NICMOS Observations of the . ... Balcells, M. HST-NICMOS Observations of Galactic . ... Baum, S.A. Investigating the Evolution of . ... Becklin, E.E. A Coronagraphic Search for . ... Clampin, M. The Old Stellar Population . ... Close, L. HST NICMOS Observations of . ... The Stellar Population in . Geballe, T.R. HST NICMOS Observations of . ... Greggio, L. The Old Stellar Population . ... Leitherer, C. The Old Stellar Population . ...

... Science Publications > Science Announcements > 8th VLTI Summer School: High angular resolution in astrophysics: optical interferometry from theory to observations . ... Observing with ESO Telescopes . ... ESO-MIDAS . ... ESO Data . ... ESO HST Image Galleries . ... ESO Data Access Policy . ... ESO Science Newsletter . ... Optical/infrared long-baseline interferometry has reached a new stage with the advent of multi-telescope arrays accessible to a broad community of astronomers, most notably VLTI . ...

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... Empirical and theoretical modeling of 3-D structures in the solar corona is confronted by the tremendous amount of data needed to represent phenomena with a large dynamic range both in size and magnitude, and with a rapid temporal evolution. Octree representation of the 3-D coronal electron distribution offers the right compromise between resolution and size, allowing computation of synthetic images of the solar corona. ... The time interval between images is one day. ...

... 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"). ...

2012 A Broadband Study of the Emission from the Composite Supernova Remnant MSH 11-62 (P. Slane et al.) ... 2012 Infrared imaging and polarimetric observations of the pulsar wind nebula in G21.5-0.9 (A. Zajczyk et al.) ... 2009 High-resolution X-ray Observations of the Pulsar Wind Nebula Associated with the Gamma-ray Source HESS J1640-465 (A. Lemiere, P. Slane, B.M. Gaensler, S.S. Murray) - ApJ, 706, 1269 . ... 1995 Soft X-Ray Emission From Selected Isolated Pulsars (P. Slane N. Lloyd) ApJ 452, L115 . ...

Static Fourier spectrometers are often used for spectral measurements of the ionosphere emissions. There are two main advantages of Fourier spectrometers (FS) - large geometric factor and high spectral resolution; these parameters are two orders better than for grating spectral instruments. ... In scanning Fourier spectrometer optical and electric modulation of signal is used to avoid this problem, for static Fourier spectrometer there are no such ways. ...

... The study of the Large-scale structure of the Universe and measurements of the Dark Energy equation of state; The exploration of the growth and cosmological evolution of supermassive Black holes in the Universe. ... In course of the all sky survey SRG will discover about 100 000 galaxy clusters and 3 million AGNs. Galaxy clusters are the largest gravitationally bounded objects in the Universe and are best explored through the study of X-ray emission from the hot intergalactic gas. ... 2016 IKI RAN ...

The Sun 11 Solar radio bursts study with high spatial and temporal resolution V.A. Alexeev, A.F. Dementyev, B.N. Lipatov, V.F. Melnikov, M.B. Nechaeva, S.D. Snegirev, Yu.V. Tikhomirov Radiophysical Research Institute NIRFI, Nizhny-Novgorod, Russia Theoretical and experimental researches of the energy release fragmentation in solar ares need observations with high spatial 0.01 1 arcsec and temporal 1 ms resolution. ... Several VLBI stations all over the Russia were supplied by this set of equipment. ...

The close position of main satellite and subsatellite (distance between them about 1000 km) and using the similar sets of Faraday cups (VDP and VDP-S) with high resolution measurements (up to 16 Hz for the main satellite and up to 10 Hz for the subsatellite) allow us to determine the small-scale variations of the magnetopause shape and position and to estimate the velocity of the magnetopause motion. ... Two point observation of the magnetopause motion: the INTERBALL project. ...

... 8, ``Celestial Mechanics'', 2002 EPM2002 and EPM2002C -- two versions of high accuracy numerical planetary ephemerides constructed for TDB and TCB time scales E. V. Pitjeva Institute of Applied Astronomy, St. Petersburg, Russia To be consistent with IAU resolutions ICRS should be treated as four-- dimensional reference frame with TCB time scale in which planetary ephemerides should be constructed. ... 2001, 80, 249-- 271. ... Standish E. M. JPL Planetary and Lunar Ephemerides, DE405/LE405. ...

The Variable Gamma-Ray Source 2CG 135+01 ApJ, 497:L89-L91, 1998 7 h gamma AGN variability . gamma-radio-AGN-variability ADS query . ... Model for the High-Energy Emission from Blazars 1993ApJ.. ... Possible Production of High-Energy Gamma Rays from Proton Acceleration in the Extragalactic Radio Source Markarian 501 astro-ph/9803241 K.Mannheim . ... A theoretical unifying scheme for gamma-ray bright blazars astro-ph/9807317 G. Ghisellini, A. Celotti, G. Fossati, L. Maraschi, A. Comastri . ...

... The motivation for this task is to create one high resolution response matrix for a set of observations without the need for creating individual high resolution matrices. ... This task creates a single response matrix file using information from a list of spectrum from multiple observations, and can also combine spectra and background spectra of the same instrument and spectral order to produce final files that can be used for futher, quantitative analysis in a fitting package such as Xspec. ...