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Title: Magnetic Field Observations at Purcell, Oklahoma Field Campaign Report

Abstract

The campaign “Magnetic Field Observations at Purcell, Oklahoma” installed a ground-based magnetometer at Purcell’s U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility boundary installation at the Kessler Atmospheric and Ecological Field Station, University of Oklahoma, to measure local magnetic field variations. It is a part of the nine stations of the Mid-continent MAgnetoseismic Chain (McMAC) placed as close to the 330° magnetic longitude as possible. This is the meridian in the world where land covers the greatest continuous range in magnetic latitude. Figure 1 shows the map of the magnetometer stations along the 330th magnetic meridian, including the Purcell (PCEL) station. The main scientific objective of the campaign is to detect the field line resonance (FLR) frequencies of the magnetic field line connected to the Purcell station. This magnetic field line extends from Purcell to the outer space at distances as far as 2 Earth radii (RE). To accurately identify FLR frequencies, however, simultaneous measurements at slightly different latitudes along the same meridian are necessary to allow the use of the cross-phase technique. This consideration explains the arrangement to operate magnetometers at the Americus (AMER) and Richardson (RICH) stations nearby. The measured resonant frequency can infermore » the plasma mass density along the field line through the method of normal-mode magnetoseismology. The magnetometer at the Purcell station can detect many other types of magnetic field fluctuations associated with the changes in the electric currents in the ionosphere and the magnetosphere, which by large are affected by the solar activity. In other words, the magnetic field data collected by this campaign are also useful for understanding space weather phenomena. The magnetometer was installed at Purcell’s ARM boundary facility in March 27, 2006. The construction of the triaxial fluxgate magnetometer used by the campaign, as well as the data processing and analysis, was sponsored by the National Science Foundation. Except during occasional downtimes, the magnetometer collected measurements from June 6, 2006 to July 26, 2016.« less

Authors:
 [1];  [2]
  1. Univ. of California, Los Angeles, CA (United States)
  2. Univ. of Oklahoma, Norman, OK (United States)
Publication Date:
Research Org.:
DOE Office of Science Atmospheric Radiation Measurement (ARM) Program, Washington, DC (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1354772
Report Number(s):
DOE/SC-ARM-17-015
DOE Contract Number:
AC05-7601830
Resource Type:
Program Document
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; 58 GEOSCIENCES; Southern Great Plains; magnetometer; field line resonance; space weather; plasma mass density

Citation Formats

Chi, P. J., and Gibson, J. P.. Magnetic Field Observations at Purcell, Oklahoma Field Campaign Report. United States: N. p., 2017. Web.
Chi, P. J., & Gibson, J. P.. Magnetic Field Observations at Purcell, Oklahoma Field Campaign Report. United States.
Chi, P. J., and Gibson, J. P.. 2017. "Magnetic Field Observations at Purcell, Oklahoma Field Campaign Report". United States. doi:. https://www.osti.gov/servlets/purl/1354772.
@article{osti_1354772,
title = {Magnetic Field Observations at Purcell, Oklahoma Field Campaign Report},
author = {Chi, P. J. and Gibson, J. P.},
abstractNote = {The campaign “Magnetic Field Observations at Purcell, Oklahoma” installed a ground-based magnetometer at Purcell’s U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility boundary installation at the Kessler Atmospheric and Ecological Field Station, University of Oklahoma, to measure local magnetic field variations. It is a part of the nine stations of the Mid-continent MAgnetoseismic Chain (McMAC) placed as close to the 330° magnetic longitude as possible. This is the meridian in the world where land covers the greatest continuous range in magnetic latitude. Figure 1 shows the map of the magnetometer stations along the 330th magnetic meridian, including the Purcell (PCEL) station. The main scientific objective of the campaign is to detect the field line resonance (FLR) frequencies of the magnetic field line connected to the Purcell station. This magnetic field line extends from Purcell to the outer space at distances as far as 2 Earth radii (RE). To accurately identify FLR frequencies, however, simultaneous measurements at slightly different latitudes along the same meridian are necessary to allow the use of the cross-phase technique. This consideration explains the arrangement to operate magnetometers at the Americus (AMER) and Richardson (RICH) stations nearby. The measured resonant frequency can infer the plasma mass density along the field line through the method of normal-mode magnetoseismology. The magnetometer at the Purcell station can detect many other types of magnetic field fluctuations associated with the changes in the electric currents in the ionosphere and the magnetosphere, which by large are affected by the solar activity. In other words, the magnetic field data collected by this campaign are also useful for understanding space weather phenomena. The magnetometer was installed at Purcell’s ARM boundary facility in March 27, 2006. The construction of the triaxial fluxgate magnetometer used by the campaign, as well as the data processing and analysis, was sponsored by the National Science Foundation. Except during occasional downtimes, the magnetometer collected measurements from June 6, 2006 to July 26, 2016.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 5
}

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