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T Van Doorsselaere - One of the best experts on this subject based on the ideXlab platform.
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
The Astrophysical Journal, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181 412 s, with an average period 290 s, consistent with the global p -mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6: 12 ◦ , 5: 82 ◦ and 15: 97 ◦ between 4170 u A continuum – G-band, G-band – Na I D1 and Na I D1 – Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of 0 ◦ between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the ‘slow’ regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 Wm 2 . The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma. Subject headings: Magnetohydrodynamics (MHD) – Sun: Chromosphere – Sun: Oscillations – Sun: Photosphere
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181-412s, with an average period ~290s, consistent with the global p-mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6.12 degrees, 5.82 degrees and 15.97 degrees between 4170 Angstrom continuum - G-band, G-band - Na I D1 and Na I D1 - Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of ~0 degrees between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the `slow' regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 W/m^2. The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma.
Gary Verth - One of the best experts on this subject based on the ideXlab platform.
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
The Astrophysical Journal, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181 412 s, with an average period 290 s, consistent with the global p -mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6: 12 ◦ , 5: 82 ◦ and 15: 97 ◦ between 4170 u A continuum – G-band, G-band – Na I D1 and Na I D1 – Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of 0 ◦ between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the ‘slow’ regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 Wm 2 . The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma. Subject headings: Magnetohydrodynamics (MHD) – Sun: Chromosphere – Sun: Oscillations – Sun: Photosphere
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181-412s, with an average period ~290s, consistent with the global p-mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6.12 degrees, 5.82 degrees and 15.97 degrees between 4170 Angstrom continuum - G-band, G-band - Na I D1 and Na I D1 - Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of ~0 degrees between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the `slow' regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 W/m^2. The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma.
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multiWavelength studies of mhd Waves in the solar chromosphere an overview of recent results
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: D B Jess, Richard Morton, V Fedun, S D T Grant, Gary Verth, Ioannis GiagkiozisAbstract:The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible Waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in Magnetohydrodynamic Wave theory, we are now in an ideal position to thoroughly investigate the role Waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.
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observations of ubiquitous compressive Waves in the sun s chromosphere
Nature Communications, 2012Co-Authors: Richard Morton, D B Jess, Gary Verth, Mihalis Mathioudakis, D Kuridze, M S Ruderman, R ErdelyiAbstract:The details of the mechanism(s) responsible for the observed heating and dynamics of the solar atmosphere still remain a mystery. Magnetohydrodynamic Waves are thought to have a vital role in this process. Although it has been shown that incompressible Waves are ubiquitous in off-limb solar atmospheric observations, their energy cannot be readily dissipated. Here we provide, for the first time, on-disk observation and identification of concurrent Magnetohydrodynamic Wave modes, both compressible and incompressible, in the solar chromosphere. The observed ubiquity and estimated energy flux associated with the detected Magnetohydrodynamic Waves suggest the chromosphere is a vast reservoir of Wave energy with the potential to meet chromospheric and coronal heating requirements. We are also able to propose an upper bound on the flux of the observed Wave energy that is able to reach the corona based on observational constraints, which has important implications for the suggested mechanism(s) for quiescent coronal heating.
D B Jess - One of the best experts on this subject based on the ideXlab platform.
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
The Astrophysical Journal, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181 412 s, with an average period 290 s, consistent with the global p -mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6: 12 ◦ , 5: 82 ◦ and 15: 97 ◦ between 4170 u A continuum – G-band, G-band – Na I D1 and Na I D1 – Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of 0 ◦ between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the ‘slow’ regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 Wm 2 . The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma. Subject headings: Magnetohydrodynamics (MHD) – Sun: Chromosphere – Sun: Oscillations – Sun: Photosphere
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181-412s, with an average period ~290s, consistent with the global p-mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6.12 degrees, 5.82 degrees and 15.97 degrees between 4170 Angstrom continuum - G-band, G-band - Na I D1 and Na I D1 - Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of ~0 degrees between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the `slow' regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 W/m^2. The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma.
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multiWavelength studies of mhd Waves in the solar chromosphere an overview of recent results
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: D B Jess, Richard Morton, V Fedun, S D T Grant, Gary Verth, Ioannis GiagkiozisAbstract:The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible Waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in Magnetohydrodynamic Wave theory, we are now in an ideal position to thoroughly investigate the role Waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.
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observations of ubiquitous compressive Waves in the sun s chromosphere
Nature Communications, 2012Co-Authors: Richard Morton, D B Jess, Gary Verth, Mihalis Mathioudakis, D Kuridze, M S Ruderman, R ErdelyiAbstract:The details of the mechanism(s) responsible for the observed heating and dynamics of the solar atmosphere still remain a mystery. Magnetohydrodynamic Waves are thought to have a vital role in this process. Although it has been shown that incompressible Waves are ubiquitous in off-limb solar atmospheric observations, their energy cannot be readily dissipated. Here we provide, for the first time, on-disk observation and identification of concurrent Magnetohydrodynamic Wave modes, both compressible and incompressible, in the solar chromosphere. The observed ubiquity and estimated energy flux associated with the detected Magnetohydrodynamic Waves suggest the chromosphere is a vast reservoir of Wave energy with the potential to meet chromospheric and coronal heating requirements. We are also able to propose an upper bound on the flux of the observed Wave energy that is able to reach the corona based on observational constraints, which has important implications for the suggested mechanism(s) for quiescent coronal heating.
S D T Grant - One of the best experts on this subject based on the ideXlab platform.
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
The Astrophysical Journal, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181 412 s, with an average period 290 s, consistent with the global p -mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6: 12 ◦ , 5: 82 ◦ and 15: 97 ◦ between 4170 u A continuum – G-band, G-band – Na I D1 and Na I D1 – Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of 0 ◦ between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the ‘slow’ regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 Wm 2 . The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma. Subject headings: Magnetohydrodynamics (MHD) – Sun: Chromosphere – Sun: Oscillations – Sun: Photosphere
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181-412s, with an average period ~290s, consistent with the global p-mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6.12 degrees, 5.82 degrees and 15.97 degrees between 4170 Angstrom continuum - G-band, G-band - Na I D1 and Na I D1 - Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of ~0 degrees between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the `slow' regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 W/m^2. The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma.
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multiWavelength studies of mhd Waves in the solar chromosphere an overview of recent results
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: D B Jess, Richard Morton, V Fedun, S D T Grant, Gary Verth, Ioannis GiagkiozisAbstract:The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible Waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in Magnetohydrodynamic Wave theory, we are now in an ideal position to thoroughly investigate the role Waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.
V Fedun - One of the best experts on this subject based on the ideXlab platform.
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
The Astrophysical Journal, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181 412 s, with an average period 290 s, consistent with the global p -mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6: 12 ◦ , 5: 82 ◦ and 15: 97 ◦ between 4170 u A continuum – G-band, G-band – Na I D1 and Na I D1 – Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of 0 ◦ between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the ‘slow’ regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 Wm 2 . The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma. Subject headings: Magnetohydrodynamics (MHD) – Sun: Chromosphere – Sun: Oscillations – Sun: Photosphere
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Wave damping observed in upwardly propagating sausage mode oscillations contained within a magnetic pore
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: S D T Grant, D B Jess, V Fedun, Ioannis Giagkiozis, Gary Verth, M G Moreels, R J Morton, D J Christian, P H Keys, T Van DoorsselaereAbstract:We present observational evidence of compressible Magnetohydrodynamic Wave modes propagating from the solar photosphere through to the base of the transition region in a solar magnetic pore. High cadence images were obtained simultaneously across four Wavelength bands using the Dunn Solar Telescope. Employing Fourier and Wavelet techniques, sausage-mode oscillations displaying significant power were detected in both intensity and area fluctuations. The intensity and area fluctuations exhibit a range of periods from 181-412s, with an average period ~290s, consistent with the global p-mode spectrum. Intensity and area oscillations present in adjacent bandpasses were found to be out-of-phase with one another, displaying phase angles of 6.12 degrees, 5.82 degrees and 15.97 degrees between 4170 Angstrom continuum - G-band, G-band - Na I D1 and Na I D1 - Ca II K heights, respectively, reiterating the presence of upwardly-propagating sausage-mode Waves. A phase relationship of ~0 degrees between same-bandpass emission and area perturbations of the pore best categorises the Waves as belonging to the `slow' regime of a dispersion diagram. Theoretical calculations reveal that the Waves are surface modes, with initial photospheric energies in excess of 35000 W/m^2. The Wave energetics indicate a substantial decrease in energy with atmospheric height, confirming that magnetic pores are able to transport Waves that exhibit appreciable energy damping, which may release considerable energy into the local chromospheric plasma.
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multiWavelength studies of mhd Waves in the solar chromosphere an overview of recent results
arXiv: Solar and Stellar Astrophysics, 2015Co-Authors: D B Jess, Richard Morton, V Fedun, S D T Grant, Gary Verth, Ioannis GiagkiozisAbstract:The chromosphere is a thin layer of the solar atmosphere that bridges the relatively cool photosphere and the intensely heated transition region and corona. Compressible and incompressible Waves propagating through the chromosphere can supply significant amounts of energy to the interface region and corona. In recent years an abundance of high-resolution observations from state-of-the-art facilities have provided new and exciting ways of disentangling the characteristics of oscillatory phenomena propagating through the dynamic chromosphere. Coupled with rapid advancements in Magnetohydrodynamic Wave theory, we are now in an ideal position to thoroughly investigate the role Waves play in supplying energy to sustain chromospheric and coronal heating. Here, we review the recent progress made in characterising, categorising and interpreting oscillations manifesting in the solar chromosphere, with an impetus placed on their intrinsic energetics.