Low frequency waves during RF heating of the ionosphere

A Surjalal Sharma, Xi Shao, Bengt Eliasson, Dennis Papadopoulos

Research output: Contribution to conferencePoster

Abstract

Radio frequency heating of the ionosphere produces local plasma heating and the resulting pressure gradient leads to plasma currents. Modulated heating excites waves at the modulation frequency which propagate away from the heating region. The wave generation modulated heating of the F-region ionosphere is modeled using a numerical code with the conducting ground as the lower boundary and the magnetosphere as the top boundary. The diamagnetic current due to the pressure gradient resulting from the localized RF heating oscillates at the modulation frequency and excites hydromagnetic waves, mostly the magnetosonic mode. As these waves propagate away from the heated region in the F-region it encounters regions of different conductivity, driving an oscillating Hall current in the E-region where Hall conductivity is dominant. These currents produce shear Alfven waves propagating along the field lines. Simulations with modulation frequencies in the range 2 – 10 Hz in the high- and mid-latitude ionosphere show their dependence on the ionospheric conductivity, modulation frequency and size of the heated region. In the high-latitudes the wave propagation is simulated using an essentially vertical magnetic field. For the mid-latitudes a dipole magnetic field in polar coordinates is used. With a source at L = 1.6 and altitude of 300 km the EMIC and whistler waves are generated, and field-aligned waves propagate to the conjugate region. In the case of modulation at 10 Hz the EMIC waves encounter the resonance layer, while the whistler waves propagate along the field lines to the conjugate region. These simulations correspond to the ionospheric heating by the Arecibo facility.

Conference

ConferenceAGU Fall Meeting
CountryUnited States
CitySan Francisco
Period15/12/1419/12/14

Fingerprint

ionospheres
low frequencies
frequency modulation
heating
F region
magnetohydrodynamic waves
pressure gradients
encounters
ionospheric heating
radio frequency heating
ionospheric conductivity
Hall currents
conductivity
polar coordinates
plasma heating
E region
wave generation
plasma currents
magnetic fields
magnetospheres

Keywords

  • radio frequency heating
  • low frequency waves
  • ionosphere

Cite this

Sharma, A. S., Shao, X., Eliasson, B., & Papadopoulos, D. (2014). Low frequency waves during RF heating of the ionosphere. Poster session presented at AGU Fall Meeting, San Francisco, United States.
Sharma, A Surjalal ; Shao, Xi ; Eliasson, Bengt ; Papadopoulos, Dennis. / Low frequency waves during RF heating of the ionosphere. Poster session presented at AGU Fall Meeting, San Francisco, United States.
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title = "Low frequency waves during RF heating of the ionosphere",
abstract = "Radio frequency heating of the ionosphere produces local plasma heating and the resulting pressure gradient leads to plasma currents. Modulated heating excites waves at the modulation frequency which propagate away from the heating region. The wave generation modulated heating of the F-region ionosphere is modeled using a numerical code with the conducting ground as the lower boundary and the magnetosphere as the top boundary. The diamagnetic current due to the pressure gradient resulting from the localized RF heating oscillates at the modulation frequency and excites hydromagnetic waves, mostly the magnetosonic mode. As these waves propagate away from the heated region in the F-region it encounters regions of different conductivity, driving an oscillating Hall current in the E-region where Hall conductivity is dominant. These currents produce shear Alfven waves propagating along the field lines. Simulations with modulation frequencies in the range 2 – 10 Hz in the high- and mid-latitude ionosphere show their dependence on the ionospheric conductivity, modulation frequency and size of the heated region. In the high-latitudes the wave propagation is simulated using an essentially vertical magnetic field. For the mid-latitudes a dipole magnetic field in polar coordinates is used. With a source at L = 1.6 and altitude of 300 km the EMIC and whistler waves are generated, and field-aligned waves propagate to the conjugate region. In the case of modulation at 10 Hz the EMIC waves encounter the resonance layer, while the whistler waves propagate along the field lines to the conjugate region. These simulations correspond to the ionospheric heating by the Arecibo facility.",
keywords = "radio frequency heating, low frequency waves, ionosphere",
author = "Sharma, {A Surjalal} and Xi Shao and Bengt Eliasson and Dennis Papadopoulos",
note = "Poster ID: SA11A-3931; AGU Fall Meeting ; Conference date: 15-12-2014 Through 19-12-2014",
year = "2014",
month = "12",
day = "15",
language = "English",

}

Sharma, AS, Shao, X, Eliasson, B & Papadopoulos, D 2014, 'Low frequency waves during RF heating of the ionosphere' AGU Fall Meeting, San Francisco, United States, 15/12/14 - 19/12/14, .

Low frequency waves during RF heating of the ionosphere. / Sharma, A Surjalal; Shao, Xi; Eliasson, Bengt; Papadopoulos, Dennis.

2014. Poster session presented at AGU Fall Meeting, San Francisco, United States.

Research output: Contribution to conferencePoster

TY - CONF

T1 - Low frequency waves during RF heating of the ionosphere

AU - Sharma, A Surjalal

AU - Shao, Xi

AU - Eliasson, Bengt

AU - Papadopoulos, Dennis

N1 - Poster ID: SA11A-3931

PY - 2014/12/15

Y1 - 2014/12/15

N2 - Radio frequency heating of the ionosphere produces local plasma heating and the resulting pressure gradient leads to plasma currents. Modulated heating excites waves at the modulation frequency which propagate away from the heating region. The wave generation modulated heating of the F-region ionosphere is modeled using a numerical code with the conducting ground as the lower boundary and the magnetosphere as the top boundary. The diamagnetic current due to the pressure gradient resulting from the localized RF heating oscillates at the modulation frequency and excites hydromagnetic waves, mostly the magnetosonic mode. As these waves propagate away from the heated region in the F-region it encounters regions of different conductivity, driving an oscillating Hall current in the E-region where Hall conductivity is dominant. These currents produce shear Alfven waves propagating along the field lines. Simulations with modulation frequencies in the range 2 – 10 Hz in the high- and mid-latitude ionosphere show their dependence on the ionospheric conductivity, modulation frequency and size of the heated region. In the high-latitudes the wave propagation is simulated using an essentially vertical magnetic field. For the mid-latitudes a dipole magnetic field in polar coordinates is used. With a source at L = 1.6 and altitude of 300 km the EMIC and whistler waves are generated, and field-aligned waves propagate to the conjugate region. In the case of modulation at 10 Hz the EMIC waves encounter the resonance layer, while the whistler waves propagate along the field lines to the conjugate region. These simulations correspond to the ionospheric heating by the Arecibo facility.

AB - Radio frequency heating of the ionosphere produces local plasma heating and the resulting pressure gradient leads to plasma currents. Modulated heating excites waves at the modulation frequency which propagate away from the heating region. The wave generation modulated heating of the F-region ionosphere is modeled using a numerical code with the conducting ground as the lower boundary and the magnetosphere as the top boundary. The diamagnetic current due to the pressure gradient resulting from the localized RF heating oscillates at the modulation frequency and excites hydromagnetic waves, mostly the magnetosonic mode. As these waves propagate away from the heated region in the F-region it encounters regions of different conductivity, driving an oscillating Hall current in the E-region where Hall conductivity is dominant. These currents produce shear Alfven waves propagating along the field lines. Simulations with modulation frequencies in the range 2 – 10 Hz in the high- and mid-latitude ionosphere show their dependence on the ionospheric conductivity, modulation frequency and size of the heated region. In the high-latitudes the wave propagation is simulated using an essentially vertical magnetic field. For the mid-latitudes a dipole magnetic field in polar coordinates is used. With a source at L = 1.6 and altitude of 300 km the EMIC and whistler waves are generated, and field-aligned waves propagate to the conjugate region. In the case of modulation at 10 Hz the EMIC waves encounter the resonance layer, while the whistler waves propagate along the field lines to the conjugate region. These simulations correspond to the ionospheric heating by the Arecibo facility.

KW - radio frequency heating

KW - low frequency waves

KW - ionosphere

UR - http://fallmeeting.agu.org/2014/

UR - https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/28359

M3 - Poster

ER -

Sharma AS, Shao X, Eliasson B, Papadopoulos D. Low frequency waves during RF heating of the ionosphere. 2014. Poster session presented at AGU Fall Meeting, San Francisco, United States.