The overall efficiency (including atmospheric transmission, reflectivity of the telescope mirrors and overall efficiency of the optics and of the detector) for broad-band imaging should be about 25% in H and K, and about 15% in J. The main noise source for both broad- and narrow-band imaging should be the photon noise associated to the background+source flux. ... Flat fielding (and possibly background subtraction) might increase the noise by a factor 2 ? ...

... 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. ...

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... In Table 14.1 we list a provisional summary of our calibration goals for Cycle 7 and Cycle 7-NICMOS. ... The present knowledge of photometric calibration does not yet permit a definitive projection of the ultimate accuracies which may be obtainable with NICMOS. ... Perforce our existing calibration data for Camera 3 have been obtained with it out of focus and therefore the estimates for its in-focus performance remain extrapolations. ... Breathing and dewar motion are approximately equal effects. ...

... Using a simple 2-D Gaussian Point Spread Function (PSF) on a constant (flat) sky background, I derive a theoretical photometric and astrometric performance model for analytical and digital PSF-fitting stellar photometry. ... The photometric performance is maximized when either the effective background area or the effective-background-level measurement error is minimized. ... An important, but frequently ignored, noise source is the uncertainty of the measurement of the effective background level ( )...

From limits to detection of a gravitational wave signal George Hobbs ATNF PPTA team. ... Jenet et al. 2005 Must look for correlated residuals Need ~20 pulsars, observed of ~5 years with rms timing residuals ~100ns Gravitational wave detection Basic ideas Jenet et al. ... 2006 New limit technique (Bill's talk) Improve timing residuals Bayesian Detection technique Gravitational wave detection A Bayesian technique for detecting gravitational waves · Work carried out by Y. Levin and R. van Haasteren. ...

stable spacetime manifold Expected to propagate at speed of light Expected to have 2 independent polarizations Sources ­ ­ ­ ­ http ://www.johnstonsarchive.net/relativity/pictures.html Unmodeled bursts Binary Coalescence Periodic Sources Stochastic Background http ://mucholderthen.tumblr.com/post/55970198303/gravitational-waves-patterns-in-space-time-a 3 LIGO-VIRGO Interferometer Gaussian Noise: Coherent Signal vs. ...

DISCLAIMER: The larger the aperture, the more light a telescope will gather and the fainter the object you can see. Here is a range of magnitudes you might expect to see. Given excellent sky conditions and good optics, a well trained eye can sometimes add up to 0.8 magnitude to these values. Limiting Magnitude depends on much more than the instruments aperture. ... One formula is for aperture in inches the other is for aperture in millimeters. ... Aperture (inches) . ... 15.2 . ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...

... S.P. KOROLEV ROCKET AND SPACE CORPORATION ENERGIA . ... OAO RSC "Energia" . ... Company's History . ... ISS Russian Segment . ... Build an operational model of neutron background environment on the station; . ... Correlation data on radiation environment parameters outside the Service Module of the ISS RS obtained through calculation with the results of measurements made by science hardware BTN-M1 and results of other Russian and international experiments; . ... 2015 JSC "S.P. Korolev RSC "Energia" ...

... 96.1655Garwood+ We presented results from a continuum VLA snapshot survey of the galactic plane in the longitude range 0d < l < 90d at 1.5 GHz. Observations were taken every 0.5^o in longitude at b=0^o. Most fields are complete to about 30 mJy peak density. The positions, peak, and total flux density of 471 compact sources (<30") have been measured. ... This catalog contains results from a continuum VLA snapshot survey of the galactic plane in the longitude range 0d < l < 90d at 1.5 GHz. ...

... Unexpected Galaxy String in the Early Universe . ... 20.01.2004 . ... NSF , NASA Explanation: How could such a long string of galaxies form so early in the universe? Several new measurements of galaxies and clusters in the early universe are reporting structures involving galaxies and clusters that are larger than expected with the new standard "dark-energy" cosmology . ... Publications with keywords: galaxies - early universe . Publications with words: galaxies - early universe . ...

Next: The Present Situation in Up: No Title Previous: Case A: . Why it is possible that the Oppenheimer-Volkoff limit exceeds ? ... The lifetime of HSP (``hot'' spinar) is completely determined by the cooling time which is of the order of s according to different calculations. ... It seems very attractive to identify this cooling time with the mean characteristic gamma-ray burst duration s! . ... Finally, for the high Oppenheimer-Volkoff limit for the cool non-rotating object, when . ...

Next: Design and Status of Up: No Title Previous: Limits on the Star . Design and Status of the NICMOS Cryocooler . ... Extending the NICMOS Lifetime . ... Expected NICMOS Performance after HST Servicing Mission 3 . NICMOS Cooling System Design . ... Creare Cryocooler . Power Conversion Electronics . Electronics Support Module . Aft-Shroud Cooling System . ... 2048 x 2048 HgCdTe Arrays for Astronomy at Visible and Infrared Wavelengths . ... Hybridization of 2048 x 2048 Arrays . ...

... 2004 January 20 . Unexpected Galaxy String in the Early Universe . ... Explanation: How could such a long string of galaxies form so early in the universe? Several new measurements of galaxies and clusters in the early universe are reporting structures involving galaxies and clusters that are larger than expected with the new standard "dark-energy" cosmology . The controversy centers on the inability of a dark-energy dominated universe to create such large structures. ... About APOD | ...

... The BL Lac objects found within DXRBS fall mostly in the range . ... A large fraction of the BL Lacs so far in our sample are at L X / L R < 10 -6.5 , the region of Figure 6 populated by LBLs. In this region of parameter space (to the left of the left-most dashed line in Figure 6), DXRBS includes objects up to two orders of magnitude fainter than the 1 Jy survey. ... For comparison, we have plotted the values for members of these three ROSAT-based surveys (DXRBS, HQS/RASS and RC) in Figure 7. ...

Introduction to Hardware Signal Injections Peter Shawhan, Isabel Leonor, Szabi MАrka (LIGO/Caltech, U. of Oregon, LIGO/Caltech) LSC Meeting March 19, 2003 LSC Meeting, 19 March 2003 Shawhan, Leonor, Marka LIGO-G030112-00-D Uses of Hardware Signal Injections Complete end-to-end test of detector and analysis Verify that detector does not distort si gnal in unexpected ways Verify that search algorithm can detect signals ! ...

In calculating the NIFS sensitivity, we adopt a read noise of 5 e - , a dark current of 0.01 e - s -1 pix -1 , and a maximum exposure time of 3600 s. Grating . ... e/pix) . ... OH Cont. (e/pix) . ... NIFS should achieve signal-to-noise ratios of ~ 10 per spectral pixel in a 0.1" 0.1" aperture for single 1800 s exposures on uniform, extended, continuum sources with surface brightnesses of J = 15.4, J = 15.0, H = 14.8, and K = 13.5 mag arcsec -2 using the Z , J , H , and K gratings, respectively. ...

In the PROJECT we are using the following peculiar . features of RATAN-600 . ... Brightness temperature sensitivity being equal to the antenna temperature sensitivity .. ... Receiver system .. ... Using aperture averaging effect. dual- beam and dual (multi-) frequency filtration, we demonstrated full filtration of the atmosphere noise down to the receiver noise at all scales of acoustics peaks ( Fig.1 , Fig 2 ). ... We select this frequency as the central one in our project. ... Antenna surface . ...

... GCN 8471 | ... TITLE: GCN CIRCULAR NUMBER: 8516 SUBJECT: GRB 081102: MASTER refind and final results DATE: 08/11/11 15:50:10 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.Parkhomenko Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalognikh Ural State GCN Circ 8470, Lipunov et al., ...