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in subjects: "Interplanetary Magnetic Fields"

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Tongues, bottles, and disconnected loops: The opening and closing of the interplanetary magnetic field

For years the field of Space Physics has had a problem, a really big problem for it occurs on the largest spatial scales in Space physics -- across the entire region under the Sun`s influence, the heliosphere. The problem is that the Sun appears to keep opening new magnetic flux into interplanetary space with no obvious way for this flux to close back off again. This state of affairs, without some previously unknown method for closing the open interplanetary magnetic field (IMF), leads to an ev… more

Date: June 1, 1994

Creator: McComas, D. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Neutrino magnetic moments and the solar neutrino problem

Present status of the neutrino magnetic moment solutions of the solar neutrino problem is reviewed. In particular, we discuss a possibility of reconciling different degrees of suppression and time variation of the signal (or lack of such a variation) observed in different solar neutrino experiments. It is shown that the resonant spin-flavor precession of neutrinos due to the interaction of their transitions magnetic moments with solar magnetic field can account for all the available solar neutr… more

Date: August 1, 1994

Creator: Akhmedov, E. Kh.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Evolution of the Interplanetary Magnetic Field

Remote observations of magnetic field topologies in the solar corona and in situ observations of the solar wind and interplanetary magnetic field (IMF) in interplanetary space are used to examine the temporal evolution of the spatial distribution of open and closed field regions emanating from the Sun. The simple ``open`` configuration of inward and outward pointing sectors in the IMF is periodically disrupted by magnetically distinct coronal mass ejections (CMEs) which erupt from previously cl… more

Date: May 1, 1993

Creator: McComas, David J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ion anisotropy driven waves in the earth`s magnetosheath and plasma depletion layer

Recent studies of low frequency waves ({omega}{sub r} {le} {Omega}{sub p}, where {Omega}{sub p} is the proton gyrofrequency) observed by AMPTE/CCE in the plasma depletion layer and magnetosheath proper arereviewed. These waves are shown to be well identified with ion cyclotron and mirror mode waves. By statistically analyzing the transitions between the magnetopause and time intervals with ion cyclotron and mirror mode waves, it is established that the regions in which ion cyclotron waves occur… more

Date: May 1, 1993

Creator: Denton, R. E.; Hudson, M. K.; Anderson, B. J.; Fuselier, S. A. & Gary, S. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar wind channels for MeV particles

Plasma, magnetic field and charged particle data from the Ulysses spacecraft is used to demonstrate that MeV particles follow channels defined by solar wind flow regimes.

Date: May 1, 1993

Creator: Page, D. E.; Goldstein, B. G. & Bame, S. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar wind thermal electron distributions

Solar wind thermal electron distributions exhibit distinctive trends which suggest Coulomb collisions and geometric expansion in the interplanetary magnetic field play keys roles in electron transport. We introduce a simple numerical model incorporating these mechanisms, discuss the ramifications of model results, and assess the validity of the model in terms of ISEE-3 and Ulysses observations. Although the model duplicates the shape of the electron distributions, and explains certain other obs… more

Date: December 1, 1991

Creator: Phillips, J. L. & Gosling, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Evolution of the interplanetary magnetic field

Remote observations of magnetic field topologies in the solar corona and in situ observations of the solar wind and interplanetary magnetic field (IMF) in interplanetary space are used to examine the temporal evolution of the spatial distribution of open and closed field regions emanating from the Sun. The simple open'' configuration of inward and outward pointing sectors in the IMF is periodically disrupted by magnetically distinct coronal mass ejections (CMEs) which erupt from previously clos… more

Date: January 1, 1993

Creator: McComas, D.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar wind channels for MeV particles

Plasma, magnetic field and charged particle data from the Ulysses spacecraft is used to demonstrate that MeV particles follow channels defined by solar wind flow regimes.

Date: January 1, 1993

Creator: Page, D.E.; Goldstein, B.G. (Jet Propulsion Lab., Pasadena, CA (United States)) & Bame, S.J. (Los Alamos National Lab., NM (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Plasma properties of driver gas following interplanetary shocks observed by ISEE-3

Plasma fluid parameters calculated from solar wind and magnetic field data obtained on ISEE 3 were studied to determine the characteristic properties of driver gas following interplanetary shocks. Of 54 shocks observed from August 1978 to February 1980, 9 contained a well defined driver gas that was clearly identifiable by a discontinuous decrease in the average proton temperature across a tangential discontinuity. While helium enhancements were present in all of 9 of these events, only about h… more

Date: January 1, 1982

Creator: Zwickl, R. D.; Asbridge, J. R.; Bame, S. J.; Feldman, W. C.; Gosling, J. T. & Smith, E. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar wind-magnetosphere coupling and the distant magnetotail: ISEE-3 observations

ISEE-3 Geotail observations are used to investigate the relationship between the interplanetary magnetic field, substorm activity, and the distant magnetotail. Magnetic field and plasma observations are used to present evidence for the existence of a quasi-permanent, curved reconnection neutral line in the distant tail. The distance to the neutral line varies from absolute value of X = 120 to 140 R/sub e/ near the center of the tail to beyond absolute value of X = 200 R/sub e/ at the flanks. Do… more

Date: September 1, 1985

Creator: Slavin, J. A.; Smith, E. J.; Sibeck, D. G.; Baker, D. N.; Zwickl, R. D.; Akasofu, S. I. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ion anisotropy driven waves in the earth's magnetosheath and plasma depletion layer

Recent studies of low frequency waves ([omega][sub r] [le] [Omega][sub p], where [Omega][sub p] is the proton gyrofrequency) observed by AMPTE/CCE in the plasma depletion layer and magnetosheath proper arereviewed. These waves are shown to be well identified with ion cyclotron and mirror mode waves. By statistically analyzing the transitions between the magnetopause and time intervals with ion cyclotron and mirror mode waves, it is established that the regions in which ion cyclotron waves occur… more

Date: January 1, 1993

Creator: Denton, R. E.; Hudson, M. K.; Anderson, B. J.; Fuselier, S. A. & Gary, S. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Structure of the magnetopause current layer at the subsolar point

A one-dimensional electromagnetic particle simulation model developed for the magnetopause current layer between the shocked solar wind and the dipole magnetic field at the subsolar point has been extended to include the interplanetary magnetic field (IMF) in the solar wind. Interaction of the solar wind with the vacuum dipole field as well as the dipole field filled with a low density magnetospheric plasma are studied. It is found that the width and the structure of the magnetopause current la… more

Date: December 1, 1991

Creator: Okuda, H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Solar wind thermal electron distributions

Date: January 1, 1991

Creator: Phillips, J.L. & Gosling, J.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solar wind-magnetosphere energy input functions

A new formula for the solar wind-magnetosphere energy input parameter, P/sub i/, is sought by applying the constraints imposed by dimensional analysis. Applying these constraints yields a general equation for P/sub i/ which is equal to rho V/sup 3/l/sub CF//sup 2/F(M/sub A/,theta) where, rho V/sup 3/ is the solar wind kinetic energy density and l/sub CF//sup 2/ is the scale size of the magnetosphere's effective energy ''collection'' region. The function F which depends on M/sub A/, the Alfven M… more

Date: January 1, 1985

Creator: Bargatze, L.F.; McPherron, R.L. & Baker, D.N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Observations of flux transfer events: Are FTEs flux ropes, islands, or surface waves

Flux transfer events (FTEs) are widely regarded as a signature of transient magnetic reconnection between the solar wind and magnetospheric plasmas. However, there is disagreement on what form this reconnection takes: Are FTEs tearing islands, or time-varying single x-line reconnection We reexamine the evidence that first led to the suggestion that FTEs are related to a non-time-stationary reconnection process. In particular we discuss how the combination of field and plasma variations suggest … more

Date: January 1, 1989

Creator: Elphic, R. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Investigation of possible sun-weather relationships

Statistical correlations between anomalous solar activity (as denoted by large solar flares, active plages, and interplanetary magnetic sector boundaries) and the circulation of the troposphere are reviewed. Two indices (measuring atmospheric vorticity and mean zonal geostrophic flow in the northern hemisphere) are analyzed in an effort to reveal possible sun-weather relationships. The result of this analysis provides no additional statistical evidence for a connection between solar activity an… more

Date: 1978

Creator: Businger, Steven

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Linear filters as a method of real-time prediction of geomagnetic activity

Important factors controlling geomagnetic activity include the solar wind velocity, the strength of the interplanetary magnetic field (IMF), and the field orientation. Because these quantities change so much in transit through the solar wind, real-time monitoring immediately upstream of the earth provides the best input for any technique of real-time prediction. One such technique is linear prediction filtering which utilizes past histories of the input and output of a linear system to create a… more

Date: January 1, 1985

Creator: McPherron, R.L.; Baker, D.N. & Bargatze, L.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Regulation of the interplanetary magnetic flux

In this study we use a recently developed technique for measuring the 2-D magnetic flux in the ecliptic plane to examine (1) the long term variation of the magnetic flux in interplanetary space and (2) the apparent rate at which coronal mass ejections (CMEs) may be opening new flux from the Sun. Since there is a substantial variation ({approximately}50%) of the flux in the ecliptic plane over the solar cycle, we conclude that there must be some means whereby new flux can be opened from the Sun … more

Date: January 1, 1991

Creator: McComas, D.J.; Gosling, J.T. & Phillips, J.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Observation in the MINOS far detector of the shadowing of cosmic rays by the sun and moon

The shadowing of cosmic ray primaries by the the moon and sun was observed by the MINOS far detector at a depth of 2070 mwe using 83.54 million cosmic ray muons accumulated over 1857.91 live-days. The shadow of the moon was detected at the 5.6 {sigma} level and the shadow of the sun at the 3.8 {sigma} level using a log-likelihood search in celestial coordinates. The moon shadow was used to quantify the absolute astrophysical pointing of the detector to be 0.17 {+-} 0.12{sup o}. Hints of Interpl… more

Date: August 1, 2010

Creator: Adamson, P.; Andreopoulos, C.; Ayres, D. S.; Backhouse, C.; Barr, G.; Barrett, W. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

New insights on geomagnetic storms from observations and modeling

Understanding the response at Earth of the Sun's varying energy output and forecasting geomagnetic activity is of central interest to space science, since intense geomagnetic storms may cause severe damages on technological systems and affect communications. Episodes of southward (Bz<O) interplanetary magnetic field (IMF) which lead to disturbed geomagnetic conditions are associated either with coronal mass ejections (CMEs) and possess long and continuous negative IMF Bz excursions, or with … more

Date: January 1, 2009

Creator: Jordanova, Vania K

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Contributions from the CYGNUS/Milagro Collaboration

This document consists of eleven reports contributed to the XXIV International Cosmic Ray Conference (Rome, Italy, August 28--September 8, 1995) from the CYGNUS/Milagro Collaboration: ``Search for Ultra-High-Energy Radiation from Gamma-Ray Bursts``, ``Gamma-Ray Bursts: Detection and Distance Estimates with Milagro``, ``Searching for Gamma-Ray Bursts with Water-Cerenkov-Detector Single-Particle Rates``, ``The Milagro Detector``, ``The Milagro Data Acquisition System``, ``Source Searches Using th… more

Date: September 1, 1995

Creator: Allen, G.E.; Chang, C.Y. & Chen, M.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Magnetic energy storage and the nightside magnetosphere-ionosphere coupling

The change m in the magnetic energy stored m in the Earth`s magnetotail as a function of the solar wind, BIF conditions are investigated using an empirical magnetic field model. The results are used to calculate the two normal modes contained m in the low-dimensional global model called WINDMI for the solar wind driven magnetosphere-ionosphere system. The coupling of the magnetosphere-ionosphere (MI) through the nightside region 1 current loop transfers power to the ionosphere through two modes… more

Date: May 1, 1998

Creator: Horton, W.; Pekker, M. & Doxas, I.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Structure and evolution of the current sheet by multi-spacecraft observations

On April 22, 1979, from 0840 to 1018 UT, ISEE 1, ISEE 2 and IMP 8 were all in or near the magnetotail current sheet at 17 Re, 16 Re and 35 Re respectively while ISEE 3 monitored the solar wind 206 Re upstream of the Earth. A global perspective of the four spacecraft observations and of the ground magnetic records is presented in this paper. The hyperbolic tangent current sheet model of Harris has been used to calculate the current sheet thickness and to analyze the plasma distribution in the ve… more

Date: December 31, 1997

Creator: Zhou, X.-Y.; Russell, C. T. & Gosling, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Global structure of mirror modes in the magnetosheath

A global stability analysis of mirror modes in the magnetosheath is presented. The analysis is based upon the kinetic-MHD formulation which includes relevant kinetic effects such as Landau resonance and gradient drift effects related to inhomogeneities in the background density, temperature, pressure and its anisotropy, magnetic field, and plasma flow velocity. Pressure anisotropy provides the free energy for the global mirror mode. The local theory of mirror modes predicts purely growing modes… more

Date: November 1, 1996

Creator: Johnson, J. R. & Cheng, C. Z.

Item Type: Report

Partner: UNT Libraries Government Documents Department