---
author:
- 'E. Pariat'
- 'K. Dalmasse'
- 'C.R. DeVore'
- 'S.K. Antiochos'
- 'J.T. Karpen'
bibliography:
- 'Jets\_param.bib'
subtitle: 'II. Parametric study of the plasma beta'
title: 'A model for straight and helical solar jets:'
---

Introduction {#sec:Introduction}
============

In the solar atmosphere, jet-like structures, defined by an impulsive evolution of a thin collimated bright or dark structure extending along a particular direction, are ubiquitous. Jet-like events are observed in a wide range of environments, on scales ranging from the limit of instrumental resolution to hundreds of Mm. They have been detected in almost all wavelengths available to observers, and have thus acquired a multitude of names: spicules [e.g., @Sterling00; @DePontieu07]; photospheric jets [e.g., @Nishizuka08; @Nishizuka11]; chromospheric [H$\alpha$]{} surges [e.g., @Schmieder95]; chromospheric Ca II H jets [e.g., @Morita10]; coronal EUV jets and macrospicules [e.g., @Nistico09; @Kamio10]; coronal X-ray jets [e.g., @Savcheva07]; and white-light polar jets [e.g., @WangYM02]. Multi-wavelength observations show slightly different spatial, physical, and temporal properties in each observational bandwidth, revealing that each jet event is formed of multi-thermal and multi-velocity plasmas [e.g., @Chifor08b; @Madjarska11; @Tian14].

In addition to the basic morphological properties that allows all these events to qualify as “jets,” several other features and properties 