1
|
Park J, Huba JD, Heelis R, Englert C. Isolated Peak of Oxygen Ion Fraction in the Post-Noon Equatorial F-Region: ICON and SAMI3/WACCM-X. JOURNAL OF GEOPHYSICAL RESEARCH. SPACE PHYSICS 2021; 126:e2021JA029217. [PMID: 34650900 PMCID: PMC8506983 DOI: 10.1029/2021ja029217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
In the equatorial region, the fraction of oxygen ions (O+) in the topside ionosphere contains information on the source altitude of the plasma, which is controlled, in part, by the vertical plasma motion in the F-region. Previous studies on this topic are restricted by limited coverage of local time, latitude, and season, leaving a significant knowledge gap in the distribution of the topside ionospheric composition. In this study, we statistically investigate the O+ fraction measured by ICON/IVM over all the local time sectors and seasons at low/midlatitudes. For the first time, we have found that an isolated peak in the O+ fraction emerges in the post-noon equatorial region. The peak is most prominent during equinoxes, while during solstices it is connected to the O+ fraction bulges in the local summer midlatitudes. Simulations with SAMI3 coupled with thermospheric parameters from WACCM-X reproduce the peak of the O+ fraction. The post-noon equatorial peak can be explained by the net vertical motion of plasma consisting of transports either parallel or perpendicular to geomagnetic field lines.
Collapse
Affiliation(s)
- Jaeheung Park
- Space Science Division, Korea Astronomy and Space Science Institute, Daejeon, South Korea
- Department of Astronomy and Space Science, Korea University of Science and Technology, Daejeon, South Korea
| | - J D Huba
- Syntek Technologies, Fairfax, VA, USA
| | - Roderick Heelis
- William B. Hanson Center for Space Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Christoph Englert
- Space Science Division, U.S. Naval Research Laboratory, Washington, DC, USA
| |
Collapse
|
2
|
Heelis RA, Stoneback RA, Perdue MD, Depew MD, Morgan WA, Mankey MW, Lippincott CR, Harmon LL, Holt BJ. Ion Velocity Measurements for the Ionospheric Connections Explorer. SPACE SCIENCE REVIEWS 2017; 212:615-629. [PMID: 30197455 PMCID: PMC6121705 DOI: 10.1007/s11214-017-0383-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 05/24/2017] [Indexed: 06/02/2023]
Abstract
The Ionospheric Connections Explorer (ICON) payload includes an Ion Velocity Meter (IVM) to provide measurements of the ion drift motions, density, temperature and major ion composition at the satellite altitude near 575 km. The primary measurement goal for the IVM is to provide the meridional ion drift perpendicular to the magnetic meridian with an accuracy of 7.5 ms-1 for all daytime conditions encountered by the spacecraft within 15° of the magnetic equator. The IVM will derive this parameter utilizing two sensors, a retarding potential analyzer (RPA) and an ion drift meter (IDM) that have a robust and successful flight heritage. The IVM described here incorporates improvements in the design and operation to produce the most sensitive device that has been fielded to date. It will specify the ion drift vector, from which the component perpendicular to the magnetic field will be derived. In addition it will specify the total ion density, the ion temperature and the fractional ion composition. These data will be used in conjunction with measurements from the other ICON instruments to uncover the important connections between the dynamics of the neutral atmosphere and the ionosphere through the generation of dynamo currents perpendicular to the magnetic field and collisional forces parallel to the magnetic field. Here the configuration and operation of the IVM instrument are described as well as the procedures by which the ion drift velocity is determined. A description of the subsystem characteristics, which allow a determination of the expected uncertainties in the derived parameters, is also given.
Collapse
|
3
|
Fang HK, Oyama KI, Cheng CZ. Electrode contamination effects of retarding potential analyzer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:015104. [PMID: 24517809 DOI: 10.1063/1.4856515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The electrode contamination in electrostatic analyzers such as Langmuir probes and retarding potential analyzers (RPA) is a serious problem for space measurements. The contamination layer acts as extra capacitance and resistance and leads to distortion in the measured I-V curve, which leads to erroneous measurement results. There are two main effects of the contamination layer: one is the impedance effect and the other is the charge attachment and accumulation due to the capacitance. The impedance effect can be reduced or eliminated by choosing the proper sweeping frequency. However, for RPA the charge accumulation effect becomes serious because the capacitance of the contamination layer is much larger than that of the Langmuir probe of similar dimension. The charge accumulation on the retarding potential grid causes the effective potential, that ions experience, to be changed from the applied voltage. Then, the number of ions that can pass through the retarding potential grid to reach the collector and, thus, the measured ion current are changed. This effect causes the measured ion drift velocity and ion temperature to be changed from the actual values. The error caused by the RPA electrode contamination is expected to be significant for sounding rocket measurements with low rocket velocity (1-2 km/s) and low ion temperature of 200-300 K in the height range of 100-300 km. In this paper we discuss the effects associated with the RPA contaminated electrodes based on theoretical analysis and experiments performed in a space plasma operation chamber. Finally, the development of a contamination-free RPA for sounding rocket missions is presented.
Collapse
Affiliation(s)
- H K Fang
- Department of Physics, National Cheng Kung University, No.1 University Rd., Tainan 70101, Taiwan
| | - K-I Oyama
- Plasma and Space Science Center, National Cheng Kung University, No.1 University Rd., Tainan 70101, Taiwan
| | - C Z Cheng
- Plasma and Space Science Center, National Cheng Kung University, No.1 University Rd., Tainan 70101, Taiwan
| |
Collapse
|
4
|
Kayser D, Breig E, Power R, Hanson W, Nier A. Direct in situ measurements of thermospheric temperature. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja084ia08p04321] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
5
|
Hanson WB, Sterling DL, Woodman RF. Source and identification of heavy ions in the equatorialFlayer. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja077i028p05530] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
6
|
Basu S. Ogo 6 observations of small-scale irregularity structures associated with subtrough density gradients. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja083ia01p00182] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
7
|
McClure JP, Hanson WB. A catalog of ionosphericFregion irregularity behavior based on Ogo 6 retarding potential analyzer data. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja078i031p07431] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
8
|
McClure JP. Thermospheric temperature variations inferred from incoherent scatter observations. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja076i013p03106] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
9
|
Rufenach CL. Power-law wavenumber spectrum deduced from ionospheric scintillation observations. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja077i025p04761] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
10
|
|
11
|
|
12
|
Bailey GJ, Moffett RJ, Hanson WB, Sanatani S. Effects of interhemisphere transport on plasma temperatures at low latitudes. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja078i025p05597] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
13
|
|
14
|
Hanson WB, Frame DR, Midgley JE. Errors in retarding potential analyzers caused by nonuniformity of the grid-plane potential. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja077i010p01914] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
15
|
Nagy AF, Brace LH, Maynard NC, Hanson WB. Is the red arc a good indicator of ionosphere-magnetosphere conditions? ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja079i028p04331] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
McClure JP, Hanson WB, Nagy AF, Cicerone RJ, Brace LH, Baron M, Bauer P, Carlson HC, Evans JV, Taylor GN, Woodman RF. Comparison ofTeandTifrom Ogo 6 and from various incoherent scatter radars. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja078i001p00197] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
17
|
Dyson PL, McClure JP, Hanson WB. In situ measurements of the spectral characteristics ofFregion ionospheric irregularities. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/ja079i010p01497] [Citation(s) in RCA: 243] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
18
|
|
19
|
Goldan PD, Yadlowsky EJ, Whipple EC. Errors in ion and electron temperature measurements due to grid plane potential nonuniformities in retarding potential analyzers. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/ja078i016p02907] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
20
|
Sanatani S, Breig EL. Winter nighttime ion temperatures and energetic electrons from OGO6 plasma measurements. ACTA ACUST UNITED AC 1981. [DOI: 10.1029/ja086ia05p03595] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
21
|
|
22
|
Variational electric fields at low latitudes and their relation to spread-F and plasma irregularities. ACTA ACUST UNITED AC 1977. [DOI: 10.1016/s0021-9169(77)90139-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
23
|
Nier AO, Hanson WB, Seiff A, McElroy MB, Spencer NW, Duckett RJ, Knight TC, Cook WS. Composition and Structure of the Martian Atmosphere: Preliminary Results from Viking 1. Science 1976; 193:786-8. [PMID: 17747780 DOI: 10.1126/science.193.4255.786] [Citation(s) in RCA: 110] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Results from the aeroshell-mounted neutral mass spectrometer on Viking I indicate that the upper atmosphere of Mars is composed mainly of CO(2) with trace quantities of N(2), Ar, O, O(2), and CO. The mixing ratios by volume relative to CO(2) for N(2), Ar, and O(2) are about 0.06, 0.015, and 0.003, respectively, at an altitude near 135 kilometers. Molecular oxygen (O(2)(+)) is a major component of the ionosphere according to results from the retarding potential analyzer. The atmosphere between 140 and 200 kilometers has an average temperature of about 180 degrees +/- 20 degrees K. Atmospheric pressure at the landing site for Viking 1 was 7.3 millibars at an air temperature of 241 degrees K. The descent data are consistent with the view that CO(2) should be the major constituent of the lower martian atmosphere.
Collapse
|