Chandra Calibration: Plans, Status, Future Herman L. Marshall ( Chandra X-ray Center, MIT Kavli Institute) HRMA Cal Summary · · · · · · · · Ground calibration Reflectivity measurements on witness samples Metrology of optical surfaces Positioning ... for finite source size and distance · Testing each quadrant of each shell separately · Allowing for illumination differences to flight Flight verification Imaging star with both ACIS and HRC Effective ...

Next: Conclusions Up: Selection Effects Previous: Inconsistent (or Inconsistently Applied) . Another possible bias, present in this as well as all other surveys which use spectral indices based upon nonsimultaneous data in their selection process, is due to variability. ... In order to minimize the effect of non-simultaneous radio survey data upon our samples, we decided to expand the common definition of flat-spectrum radio sources to extend to (instead of 0.5). ...

... 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 ( )...

Monte Carlo Methods for Including Calibration Uncertainties in Model Fitting Analyses Jeremy J. Drakea , Peter Ratzlaffa , Vinay Kashyapa , Richard Edgara , Rima Izemb , Diab Jeriusa , Herman ... University, Cambridge, MA 02138 MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 b c SUMMARY · Instrument response uncertainties almost universally ignored in astrophysical X-ray ... Limiting accuracy of Chandra ACIS reached in spectra with 10 4 counts. ...

Compilation of Surface Brightness . HyperLeda home | Documentation | Search by name | ... Search an object in the surface brightness catalogue . The surface brightness in magnitudes per square arcsec (mag arcsec -2 ) . ... Surface brightness at effective radius . ... Effective mean surface brightness within the effective radius (equivalent radius in which half the total flux is emitted). ... Quality Flag The quality flag has the following meaning: . ... regular measurement . ...

... 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. ...

A stellar library of synthetic spectra of H Balmer and HeI absorption lines . ... The grid includes the profiles of the high-order hydrogen Balmer series and HeI lines for effective temperatures and gravities that have not been previously synthesized. ... The main spectral lines synthesized are: . ... H 13 , H 12 , H 11 , H 10 , HeI 3819, H 9 , H 8 . ... that contains the following eight files with the values for the Balmer lines (H b , H d and H8) and HeI lines (3819, 4026, 4388, 4471 and 4922): . ...

Next: A Gravitational Wave Map Previous: Critical Frequencies and Gravitational . In this section we consider the GWB spectrum as such, that is, we study how dimensionless strain metric amplitude h is dependent on frequency. For a sample of N independent binaries emitting GW at a given frequency the net result is . ... are, respectively, effective distance to the sample and effective mass of the binaries (in solar units) producing the GW radiation at the frequency . ...

Detector of hydrogen isotopes (ISIV) . ... Measurements of hydrogen isotopes content in surface layer of a solid (provided that the content is more than 0.01 %). ... Content of hydrogen isotopes of a sample is measured by nondestructive technique of direct measurements in the surface layer. ... Measurable hydrogen isotopes content   ~0.01 wt. ... Area surface of sample                                         ~10 cm 2 . ... G. Dolnikov +7(495)333-25-66, ggd@iki.rssi.ru . ...

... Request : 22232.00 MHz; BW : 64.00 MHz ! ODD inversion (at sampler); LO phase sign : -1 bits : 4 ! effective LO : -22328.00 offset : 0.0000 band centre : 22232.0000 (all MHz) ! LO f_LO !W 27200.00 !CX 7350.00 !LS 1965.00 !L4 513.00 ! ... Inversion after sampler EVEN ! ... Inversion after sampler EVEN !Turret already at KQ WILTRON,68037B,510001,1.06 Wiltron # 1 RESET WILTRON,68045B,670015,1.08 Wiltron # 2 RESET Wiltron #1 freq : 13600.000000 MHz Wiltron #1 level : 8.0 dBm Wiltron #1 RF ON ! ...

... In spite of the good potential possibilities, some of the station "Dnepr" design characteristics did not allow us to apply the usual special IS radar measurement methods. ... Thus for IS signal measurements at the "Dnepr" station, we have developed special methods for recording and processing IS signals in order to determine plasma ionospheric parameters. ... Equations (4-5) from the basis for data post processing to obtain ionosphere parameters. ...

A Model Based Approach to LOFAR Calibration and Imaging Stefan J. Wijnholds e-mail: wijnholds @astron.nl AAVP Workshop Cambridge (UK), 8 ­ 10 December 2010 AAVP Workshop , Cambridge , 8 ­ 10 December 2010 -1- The model based approach Traditional approach Model based approach relation between visibility and image planes (FT) ... AAVP Workshop, Cambridge, 8 ­ 10 December 2010 -7- SP example: KL-transform S.J. Wijnholds & A.J. van der Veen, ICASSP 2011, submitted LS-image vs. ...

... 1.Magnetic and magneto-elastic properties of heavy rare earth metals. ... High magnetic fields of 100 kOe and more were necessary to saturate the magnetization of havy rare earth metals. ... It was shown that the effective exchange field theory is sufficient for the description of the magnetic order in heavy rare earth metals and their compounds. ... The duality of the state of the magnetic carriers in the traditional 3d-magnetic materials. ... LHPP ISSP RAS © 2004 All rights reserved ...

... Key words: stars: magnetic fields ­ stars: chemically p eculiar 1 Intro duction On the basis of all the available published magnetic measurements for Ap stars we have found a few relations describing the frequency of o ccurrence of the sp ecific magnetic field intensity for all typ es of chemical p eculiarities (Bychkov et al. 2003a). ... Magnetization of stars in the `strongly'-magnetic group exceeds that in the `weak'-magnetic group typically by a factor of 5­10, on the average. ...

... Strange visual effects would appear as documented in the above relativistically-accurate animation . First of all, relativistic aberration would cause objects to appear to bunch up in front you. Next, the Doppler shift would cause the colors of forward objects to shift toward the blue, while things behind you would shift toward the red. ... NASA Web Site Statements, Warnings, and Disclaimers . ... Publications with keywords: motion - color . Publications with words: motion - color . ...

. First page Back Continue Last page Summary Graphics . First cut, cross calibrate to Leiden-Dwingeloo (0.5 ) . This tends to smooth out total column changes on small scales, but preserves velocity features .

TOWARDS SUPERSENSITIVE BOLOMETERS AND ELECTRON COOLERS BASED ON CARBON NANOTUBES M.TARASOV, J.SVENSSON, S.DITTMER, L.KUZMIN, AND E.CAMPBELL Chalmers University of Technology, GЖteborg SE 41294, Sweden E-mail: Mikhail.tarasov@mc2.chalmers.se Carbon nanotubes (CNT) are being intensively developed for novel electronics. Electron cooling by superconductor-insulator-nanotube (SIN) tunnel junctions could be extremely effective due to the small volume of the CNT. ...

SKA ­ TDT Group On Phase Computation during Folding C.Baffa, E.Giani January 2014 The last part of pulsar search algorithm, as in the SKA TDT group approach, is the verification and optimization of pulsar parameters candidates identified in the previous phases. ... As the phase errors are expressed as fractions of the full period (in our case 44 measurement of 50 s), it is evident that the maximum integration time compatible with single precision phase computation is very short. ...

... 2011 October 18 . Movie: Approaching Light Speed . ... Explanation: What would it look like to travel near the speed of light? Strange visual effects would appear as documented in the above relativistically-accurate animation . First of all, relativistic aberration would cause objects to appear to bunch up in front you. ... About APOD | ... NASA Official: Phillip Newman Specific rights apply . NASA Web Privacy Policy and Important Notices . A service of: ASD at NASA / GSFC . ...

home education . SEARCH ASP SITE: Match ALL words Match ANY word . ... SEED Grants to Scientists . ... The ASP SEED Grant program supports the ASP's mission to advance science and science literacy through astronomy by encouraging active researchers to engage in public outreach, K-14 formal education, or informal education programs or activities. ... Development, use, and dissemination of a well-illustrated college-level presentation on a specific topic or problem in current research . ... search . ...