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Haddock, F. T.

Publications and source records attributed to Haddock, F. T..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Radio observations of interplanetary magnetic field structures out of the ecliptic

Observations of the out-of-ecliptic trajectories of type III solar radio bursts have been obtained from simultaneous direction-finding measurements in two independent satellite experiments, IMP-6 with spin plane in the ecliptic and RAE-2 with spin plane normal to the ecliptic. Burst-exciter trajectories were observed which originated at the active region and then crossed the ecliptic plane at about 0.8 AU. A considerable large-scale north-south component of the interplanetary magnetic field followed by the exciters is found. The apparent north-south and east-west angular source sizes observed by the two spacecraft are approximately equal, and range from 25 deg at 600 kHz to 110 deg at 80 kHz.

Fitzenreiter, R. J.↗
NASA NTRS1976

Radio observations of interplanetary magnetic field structures out of the ecliptic

New observations of the out-of-the ecliptic trajectories of type 3 solar radio bursts have been obtained from simultaneous direction finding measurements on two independent satellite experiments, IMP-6 with spin plane in the ecliptic, and RAE-2 with spin plane normal to the ecliptic. Burst exciter trajectories were observed which originated at the active region and then crossed the ecliptic plane at about 0.8 AU. A considerable large scale north-south component of the interplanetary magnetic field is followed by the exciters. The apparent north-south and east-west angular source sizes observed by the two spacecraft are approximately equal, and range from 25 deg at 600 KHz to 110 deg at 80 KHz.

Fitzenreiter, R. J.↗
NASA NTRS1975

OGO-V radio burst analysis

An analysis is presented of data on the km-wave type-3 bursts associated with H alpha flares. A list of published papers based on previous analysis is also presented.

Haddock, F. T.↗
NASA NTRS1974

Kilometer-wave type III burst - Harmonic emission revealed by direction and time of arrival

A type III solar burst was observed at seven frequencies between 3.5 MHz and 80 kHz by the Michigan experiment aboard the IMP-6 satellite. From the data burst direction of arrival as well as time of arrival can be determined. These quantities are predicted, using simple models whose parameters are varied to obtain a good fit to the observations. It is found that between 3.5 MHz and 230 kHz the observed radiation was emitted at the fundamental of the local plasma frequency, while below 230 kHz it was emitted at the second harmonic. The exciter particles that produced the burst onset and burst peak have velocities of 0.27 and 0.12, respectively, in units of the velocity of light.

Alvarez, H.↗
NASA NTRS1973

Decay time of type III solar bursts observed at kilometric wavelengths.

Type III bursts were observed between 3.5 MHz and 50 kHz by the University of Michigan radio astronomy experiment aboard the OGO-5 satellite. Decay times were measured and then combined with published data ranging up to about 200 MHz. The observed decay times increase with decreasing frequency, but at a rate considerably slower than that expected from electron-proton Coulomb collisions. At 50 kHz, values differ by about a factor of 100. Using Hartle and Sturrock's solar wind model, Coulomb collisional frequencies were computed and compared with the apparent collisional frequencies deduced from the observations. It was found that the ratio of observed to computed values varies with heliocentric distance according to an inverse 0.71 power.

Alvarez, H.↗
NASA NTRS1973

The prevalence of second harmonic radiation in type III bursts observed at kilometric wavelengths.

We present the analysis of 64 type III solar bursts that drifted from 3.5 MHz down to the range 350-50 kHz between March 1968 and February 1970. Bursts arrival times were predicted by a simple model and then compared with observations. The results show that, as the bursts drift, the fundamental often disappears below a certain frequency range while the second harmonic remains. Below about 1 MHz, the second harmonic occurrence predominates. Recognizing this fact we deduce a mean velocity of 0.32c plus or minus 0.02c for the exciter particles, where the uncertainty is the standard error and c the velocity of light in vacuum; the electron density model used is comparable to a solar wind model.

Haddock, F. T.↗
NASA NTRS1973

Solar wind density model from km-wave type III bursts.

The analysis of type III bursts observed from the OGO-5 satellite between 3.5 MHz and 50 kHz gives an empirical expression for the frequency drift rate as a function of frequency that is valid from 75 kHz to 550 MHz. Using this expression and some simplifying assumptions we obtain indirectly an empirical formula for the electron density distribution of the solar wind to 1 AU which is consistent with published values of electron density and with observed type III burst drift rates.

Alvarez, H.↗
NASA NTRS1973

Decay time of type 3 solar bursts

Type 3 solar bursts observed by OGO-5, below 600 kHz, were analyzed. Decay times were measured, and collisional decay times were computed for distances out to 1 AU. By fitting power functions to the computed and observed decay times, and using local plasma hypothesis, it was found that the ratio rho of computed observed values varies with heliocentric radial distance according to a power function rho = 3r to the 0.7th power, assuming fundamental emission, and rho = 2r to the 0.7th power, assuming second harmonic emission.

Alvarez, H.↗
NASA NTRS1971

Instrumentation for radio astronomy measurements aboard the IMP-I spacecraft

The design considerations and performance parameters of a satellite-borne instrumentation system are discussed. The system is designed to make radio astronomy measurements at eight discrete frequencies from 50 kHz to 3.53 MHz. These measurements are to detect solar and Jovian radio frequency bursts and to determine the average cosmic background radiation level down to 50 kHz. Procedures used for preflight and inflight calibration of the radiometer and the ground support equipment used for preflight testing are described.

Haddock, F. T.↗
NASA NTRS1971

The 2-8 GHz solar dynamic spectra and polarization measurement feasibility study

The preliminary system design of a Solar Microwave Spectrograph (SMS) is presented. This design resulted from a study to determine the feasibility of measuring solar polarization and dynamic spectra over the range of two to eight GHz, using broadband radio frequency instrumentation and rapid recording equipment in conjunction with radio telescopes. The scientific value of the proposed SMS instrument is discussed, with remarks concerning data reduction and analysis and a presentation of the engineering plan to implement the SMS system.

Haddock, F. T.↗
NASA NTRS1970

Data user's notes of the radio astronomy experiment aboard the OGO-V spacecraft

General information concerning the low-frequency radiometer, instrument package launching and operation, and scientific objectives of the flight are provided. Calibration curves and correction factors, with general and detailed information on the preflight calibration procedure are included. The data acquisition methods and the format of the data reduction, both on 35 mm film and on incremental computer plots, are described.

Haddock, F. T.↗
NASA NTRS1967

Space astronomy

Astronomical observations through X-ray, ultraviolet, and radio astronomy

RADIO ASTRONOMY↗