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6,193
Convergence rates of recursive Newtontype methods for multifrequency scattering problems
"... We are concerned with the reconstruction of a soundsoft obstacle using far field measurements of the scattered waves associated with incident plane waves sent from one direction but at multiple frequencies. We define, for each frequency, the observable shape as the one which is described by finitel ..."
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We are concerned with the reconstruction of a soundsoft obstacle using far field measurements of the scattered waves associated with incident plane waves sent from one direction but at multiple frequencies. We define, for each frequency, the observable shape as the one which is described
Inverse Acoustic and Electromagnetic Scattering Theory, Second Edition
, 1998
"... Abstract. This paper is a survey of the inverse scattering problem for timeharmonic acoustic and electromagnetic waves at fixed frequency. We begin by a discussion of “weak scattering ” and Newtontype methods for solving the inverse scattering problem for acoustic waves, including a brief discussi ..."
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Cited by 1072 (45 self)
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Abstract. This paper is a survey of the inverse scattering problem for timeharmonic acoustic and electromagnetic waves at fixed frequency. We begin by a discussion of “weak scattering ” and Newtontype methods for solving the inverse scattering problem for acoustic waves, including a brief
Multifrequency Inverse Obstacle Scattering . . .
, 2003
"... This work is a study of strategies for obstacle reconstruction from multifrequency far field scattering data. We outline two strategies for obstacle reconstruction from multifrequency far field scattering data: the point source method proposed by Potthast for solving inverse scattering problems with ..."
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Cited by 6 (5 self)
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This work is a study of strategies for obstacle reconstruction from multifrequency far field scattering data. We outline two strategies for obstacle reconstruction from multifrequency far field scattering data: the point source method proposed by Potthast for solving inverse scattering problems
ThreeYear Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Temperature Analysis. On arXiv.org: astroph/0603451
, 2006
"... A simple cosmological model with only six parameters (matter density, Ωmh 2, baryon density, Ωbh 2, Hubble Constant, H0, amplitude of fluctuations, σ8, optical ..."
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Cited by 362 (7 self)
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A simple cosmological model with only six parameters (matter density, Ωmh 2, baryon density, Ωbh 2, Hubble Constant, H0, amplitude of fluctuations, σ8, optical
Multifrequency integrated profiles of pulsars
 MNRAS
, 2008
"... We have observed a total of 67 pulsars at five frequencies ranging from 243 to 3100 MHz. Observations at the lower frequencies were made at the Giant Metre Wave Telescope in India and those at higher frequencies at the Parkes Telescope in Australia. ..."
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Cited by 1 (0 self)
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We have observed a total of 67 pulsars at five frequencies ranging from 243 to 3100 MHz. Observations at the lower frequencies were made at the Giant Metre Wave Telescope in India and those at higher frequencies at the Parkes Telescope in Australia.
Multifrequency studies of ionospheric s intillations
, 1976
"... Simultaneous scintillation data from the ATS6 Radio Beacon Experiments for signals at 40, 140, and 360 MHz offer the opportunity to study the frequency dependence of the scintillation phenomenon. Using these data variations of the spectral index, correlation coefficient, and the correlation interva ..."
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Simultaneous scintillation data from the ATS6 Radio Beacon Experiments for signals at 40, 140, and 360 MHz offer the opportunity to study the frequency dependence of the scintillation phenomenon. Using these data variations of the spectral index, correlation coefficient, and the correlation interval are investigated. It is found that for weak scintillations, the spectral indices lie between 1.5 and 1.7. When the scintillation is strong, the spectral indices vary from about 1.4 to 0.7. The correlation coefficients are found to decrease for increasing scintillation level. The interesting behavior of the correlation intervals as functions of signal frequency is also discussed. The observational results are compared with theoretical predictions. 1.
Multifrequency observations of VLBL objects
"... We present the SED of three BL Lac objects with the peak of their synchrotron emission at very low ( ≃ 10 13 Hz) frequency, using groundbased radio (5 GHz) and opticalNIR data, UV and Xray data from Swift satellite. A logparabolic fit was applied to the data around the peak region, joined to a p ..."
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We present the SED of three BL Lac objects with the peak of their synchrotron emission at very low ( ≃ 10 13 Hz) frequency, using groundbased radio (5 GHz) and opticalNIR data, UV and Xray data from Swift satellite. A logparabolic fit was applied to the data around the peak region, joined to a powerlaw in the radio. The sources showed a large flux variability, an increase of the peak frequency and a flattening of the spectral shape at higher fluxes. A comparison of the (log)shifts of the synchrotron peak and flux level of these LBL sources with that of an HBL one (Mrk 421) indicates that the same physical mechanism originates the flux variability of these objects, despite the large difference in peak frequency, and therefore physical parameters of the jets. PoS(BLAZARS2008)077 Workshop on Blazar Variability across the Electromagnetic Spectrum
Results 1  10
of
6,193