Modelling of explosive events  in the solar transition 
region in a 2D environment

Roussev, I. I.; Galsgaard, K.; Erdélyi, R.; Doyle, J. G.

doi:10.1051/0004-6361:20010207

Cited by 49 publications

(51 citation statements)

References 22 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dynamics of magnetic reconnection in the reference experiment, "R", is similar to that discussed in Roussev et al (2001), except that in the latter case, the localised magnetic diffusion operates for 5 time units, instead of 1 assigned here.…”

Section: Dynamic Consequences Of the Inclusion Of Anomalous Resistivitymentioning

confidence: 70%

“…We consider the same model of a 2D magnetized atmosphere presented in Roussev et al (2001). We allow for a shallow temperature gradient along the field lines, and thus examine physical circumstances that represent a solar transition region 4 .…”

Section: Initial Statementioning

confidence: 99%

“…The effect of gravity is neglected for the sake of simplicity. We refer to Roussev et al (2001) for a detailed description of the initial configuration. Note that all the formulas and relations presented below are given in terms of normalized physical quantities and model parameters.…”

Section: Initial Statementioning

confidence: 99%

“…The reconnection process is initiated again in an ad hoc manner by enhancing the resistivity 1 locally and for a short period of time in the current sheet. The dynamic evolution of magnetic reconnection for a long duration of the "driving" process was reported in Roussev et al (2001). Our task now is to investigate again the dynamics of this evolving system, but including the effects of anomalous resistivity with an explicit form different than that used to initiate the reconnection process.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Physical consequences of the inclusion of anomalous resistivity in the dynamics of 2D magnetic reconnection

Roussev¹,

Galsgaard²,

Judge³

2002

A&A

Self Cite

View full text Add to dashboard Cite

Abstract. The aim of the present paper is to explore the role of anomalous resistivity on the dynamics of magnetic reconnection in a 2D environment of relevance to the solar transition region. We adopt an ad hoc but explicit form of the anomalous resistivity, motivated by a streaming instability, in which the resistivity jumps suddenly as the electron drift velocity exceeds some fraction of the mean electron thermal speed. Experiments have been conducted to investigate the impact of various critical speeds and arbitrary scaling constants of the resistivity level on the time-dependent evolution of the magnetic reconnection process. The specific threshold value is found to influence the dynamics of the reconnection, with higher values providing a localised on-off effect of patchy diffusion. For a given normalised value of the anomalous resistivity, the amount of Joule heating released scales inversely with the threshold value. The total energy release is found to be above the lower limit of "quiet" Sun nano-flares required to maintain a hot corona. The reconnection events discussed here may be important to the energy balance of the solar transition region and overlying corona, as already suggested in earlier work based on SUMER observations.

show abstract

Section: Dynamic Consequences Of the Inclusion Of Anomalous Resistivitymentioning

confidence: 70%

Section: Initial Statementioning

confidence: 99%

Section: Initial Statementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Physical consequences of the inclusion of anomalous resistivity in the dynamics of 2D magnetic reconnection

Roussev¹,

Galsgaard²,

Judge³

2002

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…Magnetic reconnection at the current sheet is initiated by introducing localized anomalous resistivity. Roussev et al (2001a) carried out 2D MHD simulations, where jet-like events are formed during the process of magnetic reconnection. In their model, the initial magnetic field is parallel to the y-axis (vertical), and there is a thin current concentration formed along the y-axis.…”

Section: Introductionmentioning

confidence: 99%

Chromospheric magnetic reconnection caused by photospheric flux emergence: implications for jet-like events formation

Ding¹,

Madjarska²,

Doyle³

et al. 2010

A&A

Self Cite

View full text Add to dashboard Cite

Magnetic reconnection in the low atmosphere, e.g. chromosphere, is investigated in various physical environments. Its implications for the origination of explosive events (small-scale jets) are discussed. A 2.5-dimensional resistive magnetohydrodynamic (MHD) model in Cartesian coordinates is used. It is found that the temperature and velocity of the outflow jets as a result of magnetic reconnection are strongly dependent on the physical environments, e.g. the magnitude of the magnetic field strength and the plasma density. If the magnetic field strength is weak and the density is high, the temperature of the jets is very low (∼10 4 K) as well as its velocity (∼40 km s −1 ). However, if environments with stronger magnetic field strength (40 G) and smaller density (electron density N e = 2 × 10 10 cm −3 ) are considered, the outflow jets reach higher temperatures of up to 6 × 10 5 K and a line-of-sight velocity of up to 130 km s −1 which is comparable with the observational values of jet-like events.

show abstract

Heating of the solar and stellar coronae: a review

Erdélyi¹,

Ballai

2007

Astron Nachr

Self Cite

View full text Add to dashboard Cite

Despite great advances in observations and modelling, the problem of solar and stellar heating still remains one of the most challenging problems of space physics. To find a definite answer to what sort of mechanisms act to heat the plasma to a few million degrees requires a collaborative effort of small scales observations, large capacity numerical modelling and complicated theoretical approaches. A unique theory should incorporate aspects such as the generation of energy, its transport and dissipation. Up to now, the first two problems are rather clarified. However, the modality of transfer of magnetic or kinetic energy into heat is a question still awaiting for an answer. In the present paper we review the various popular heating mechanisms put forward in the existing extensive literature. The heating processes are, somewhat arbitrarily, classified as hydrodynamic, magnetohydrodynamic or kinetic based on the characteristics of the model medium. These mechanisms are further divided based on the time scales of the ultimate dissipation involved (i.e. AC and DC heating, turbulent heating). In particular, special attention is paid to discuss shock dissipation, mode coupling, resonant absorption, phase mixing, and, reconnection. Finally, we briefly review the various heating mechanisms proposed to heat other stars.

show abstract

Modelling of explosive events in the solar transition region in a 2D environment

Cited by 49 publications

References 22 publications

Physical consequences of the inclusion of anomalous resistivity in the dynamics of 2D magnetic reconnection

Physical consequences of the inclusion of anomalous resistivity in the dynamics of 2D magnetic reconnection

Chromospheric magnetic reconnection caused by photospheric flux emergence: implications for jet-like events formation

Heating of the solar and stellar coronae: a review

Contact Info

Product

Resources

About