Stephen M. White

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A radio frequency interference (RFI) excision algorithm based on spectral domain statistics is proposed and implemented in software. The algorithm requires the use of two memory buffers, S 1 and S 2 , in which the first two powers of M power spectral density (PSD) estimates, obtained via Fast Fourier Transform (FFT), are accumulated and used to form a(More)
The temporal relationship between coronal mass ejections (CMEs) and associated solar Ñares is of great importance to understanding the origin of CMEs, but it has been difficult to study owing to the nature of CME detection. In this paper, we investigate this issue using the Large Angle and Spectro-metric Coronagraph and the EUV Imaging Telescope(More)
—This paper deals with a feasibility study for a System-on-Chip (SoC) mm-wave radiometer devoted to space-based observation of solar flares and operating in the Ka-band. The radiometer has been designed in 250 nm SiGe BiCMOS process. The circuit integrates a three stages differential LNA with 37.2 dB gain and 4.8 dB noise figure at 36.8 GHz and a(More)
We present the first spectroscopic images of solar radio transients from the prototype for the Murchison Widefield Array, observed on 2010 March 27. Our observations span the instantaneous frequency band 170.9– 201.6 MHz. Though our observing period is characterized as a period of " low " to " medium " activity, one broadband emission feature and numerous(More)
We present a detailed examination on the nonthermal emissions during the preflare phase of the X4.8 flare that occurred on 2002 July 23. The microwave (17 GHz and 34 GHz) data obtained with Nobeyama Radioheliograph, at Nobeyama Solar Radio Observatory and the hard X-ray data taken with Reuven Ramaty High Energy Solar Spectroscopic Imager obviously showed(More)
Determining the 3D coronal magnetic field is a critical, but extremely difficult problem to solve. Since different types of multiwavelength coronal data probe different aspects of the coronal magnetic field, ideally these data should be used together to validate and constrain specifications of that field. Such a task requires the ability to create(More)
The weak-lined T Tauri stars have been found to be amongst the most radio-luminous of all active stars, although their distance (> 150 pc) makes them diicult to study. Here we present observations of the radio spectra and circular polarization of a number of these objects, and compare their properties with those of other classes of active stars. THE RADIO(More)
One of the largest solar hard X-ray (HXR) flares and solar energetic particle (SEP) events recorded by the Mars Odyssey mission while orbiting Mars occurred on 2002 October 27 and is related to a very fast (∼2300 km s) coronal mass ejection (CME). From the Earth, the flare site is 40.4Њ ‫ע‬ 3.5Њ behind the solar limb and Ϫ1 only emissions from the high(More)
The measurement of magnetic field strengths in the solar corona using radio observations is reviewed. This is a well established technique that exploits the fact that the electron gyrofrequency for typical coronal magnetic field strengths (100–2000 Gauss) lies in the radio frequency range. Opacity from the resulting gyroresonance emission from hot plasma(More)