One dimensional prominence threads: I. Equilibrium models

Abstract

Threads are the building blocks of solar prominences and very often show longitudinal oscillatory motions that are strongly attenuated with time. The damping mechanism responsible for the reported oscillations is not fully understood yet. To understand the oscillations and damping of prominence threads it is mandatory to investigate first the nature of the equilibrium solutions that arise under static conditions and under the presence of radiative losses, thermal conduction and background heating. This provides the basis to calculate the eigenmodes of the thread models. The nonlinear ordinary differential equations for hydrostatic and thermal equilibrium under the presence of gravity are solved using standard numerical techniques and simple analytical expressions are derived under certain approximations. The solutions to the equations represent a prominence thread, i.e., a dense and cold plasma region of a certain length that connects with the corona through a prominence corona transition region (PCTR). The solutions can also match with a chromospheric-like layer if a spatially dependent heating function localised around the footpoints is considered. We have obtained static solutions representing prominence threads and have investigated in detail the dependence of these solutions on the different parameters of the model. Among other results, we have shown that multiple condensations along a magnetic field line are possible, and that the effect of partial ionisation in the model can significantly modify the thermal balance in the thread and therefore their length. This last parameter is also shown to be comparable to that reported in the observations when the radiative losses are reduced for typical thread temperatures.

arXiv commentAccepted for publication in A&A

References in corpus (16)

• Formation and evolution of a multi-threaded prominence
• Thermal Instability with Anisotropic Thermal Conduction and Adiabatic Cosmic Rays: Implications for Cold Filaments in Galaxy Clusters
• Large Amplitude Longitudinal Oscillations in a Solar Filament
• The Field Condition: A New Constraint of Spatial Resolution in Simulations of the nonlinear Development of Thermal Instability
• Observation and Simulation of Longitudinal Oscillations of an Active Region Prominence
• Can Thermal Nonequilibrium Explain Coronal Loops?
• Parametric survey of longitudinal prominence oscillation simulations
• GONG Catalog of Solar Filament Oscillations Near Solar Maximum
• On the Support of Solar Prominence Material by the Dips of a Coronal Flux Tube
• A Fast and Accurate Method to Capture the Solar Corona/Transition Region Enthalpy Exchange
• Stability of thermal modes in cool prominence plasmas
• Time damping of non-adiabatic magnetohydrodynamic waves in a partially ionized prominence plasma: Effect of helium
• Transition region adaptive conduction (TRAC) in multidimensional magnetohydrodynamic simulations
• Modelling the Effect of Mass-Draining on Prominence Eruptions
• Dependence of the Length of Solar Filament Threads on the Magnetic Configuration
• The Thermal Instability of Solar Prominence Threads

Cited by in corpus (3)

• Self-consistent equilibrium models of prominence thin threads heated by Alfvén waves propagating from the photosphere
• Formation and Characteristics of Filament Threads in Double-Dipped Magnetic Flux Tubes
• The role of ambipolar heating in the energy balance of solar prominences