11,810 research outputs found
A study of the effect of surfaces on oxygen atom recombination at low pressures Technical status report no. 1, May 1 - Oct. 31, 1967
Catalytic effects of materials surfaces on oxygen atom recombination at low pressure
Chemiluminescent reaction processes pertinent to the chemosphere in the micron pressure region
Chemiluminescent reaction processes in vacuum system operating in micron pressure regio
Photodissociation of NO2 by pulsed laser light at 6943 A
Two photon absorption in photodissociation of nitrogen dioxide using pulsed laser at 6943
A study of the effect of surfaces on oxygen atom recombination at low pressures Technical status report no. 3, 1 May - 31 Oct. 1968
Oxygen recombination on various metal surfaces at low pressure
Isotopic enrichment of nitrogen in the photolysis of NO
Isotopic enrichment of nitrogen in photolysis of N
A study of the effect of surfaces on oxygen atom recombination at low pressures Technical status report, 1 Nov. 1968 - 30 Apr. 1969
Satellite mass spectrometer measurements of metal surfaces interacting with oxygen atom at low pressure
Gamma-Ray Bursts observed by XMM-Newton
Analysis of observations with XMM-Newton have made a significant contribution
to the study of Gamma-ray Burst (GRB) X-ray afterglows. The effective area,
bandpass and resolution of the EPIC instrument permit the study of a wide
variety of spectral features. In particular, strong, time-dependent, soft X-ray
emission lines have been discovered in some bursts. The emission mechanism and
energy source for these lines pose major problems for the current generation of
GRB models. Other GRBs have intrinsic absorption, possibly related to the
environment around the progenitor, or possible iron emission lines similar to
those seen in GRBs observed with BeppoSAX. Further XMM-Newton observations of
GRBs discovered by the Swift satellite should help unlock the origin of the GRB
phenomenon over the next few years.Comment: To appear in proceedings of the "XMM-Newton EPIC Consortium meeting,
Palermo, 2003 October 14-16", published in Memorie della Societa Astronomica
Italian
New insights into ultraluminous X-ray sources from deep XMM-Newton observations
The controversy over whether ultraluminous X-ray sources (ULXs) contain a new
intermediate-mass class of black holes (IMBHs) remains unresolved. We present
new analyses of the deepest XMM-Newton observations of ULXs that address their
underlying nature. We examine both empirical and physical modelling of the
X-ray spectra of a sample of thirteen of the highest quality ULX datasets, and
find that there are anomalies in modelling ULXs as accreting IMBHs with
properties simply scaled-up from Galactic black holes. Most notably, spectral
curvature above 2 keV in several sources implies the presence of an
optically-thick, cool corona. We also present a new analysis of a 100 ks
observation of Holmberg II X-1, in which a rigorous analysis of the temporal
data limits the mass of its black hole to no more than 100 solar masses. We
argue that a combination of these results points towards many (though not
necessarily all) ULXs containing black holes that are at most a few 10s of
solar mass in size.Comment: 5 pages, 2 figures, to appear in the proceedings of "The X-ray
Universe 2005", San Lorenzo de El Escorial (Spain), 26-30 September 200
Development and application of a non-Gaussian atmospheric turbulence model for use in flight simulators
A method is described for generating time histories which model the frequency content and certain non-Gaussian probability characteristics of atmospheric turbulence including the large gusts and patchy nature of turbulence. Methods for time histories using either analog or digital computation are described. A STOL airplane was programmed into a 6-degree-of-freedom flight simulator, and turbulence time histories from several atmospheric turbulence models were introduced. The pilots' reactions are described
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