Solar Jets Research Articles

Another Look at Erupting Minifilaments at the Base of Solar X-Ray Polar Coronal “Standard” and “Blowout” Jets

Abstract We examine 21 solar polar coronal jets that we identify in soft X-ray images obtained from the Hinode/X-ray telescope (XRT). We identify 11 of these as blowout jets and four as standard jets (with six uncertain), based on their X-ray-spire widths being respectively wide or narrow (compared to the jet’s base) in the XRT images. From corresponding extreme ultraviolet (EUV) images from the Solar Dynamics Observatory’s (SDO) Atmospheric Imaging Assembly (AIA), essentially all (at least 20 of 21) of the jets are made by minifilament eruptions, consistent with other recent studies. Here, we examine the detailed nature of the erupting minifilaments (EMFs) in the jet bases. Wide-spire (“blowout”) jets often have ejective EMFs, but sometimes they instead have an EMF that is mostly confined to the jet’s base rather than ejected. We also demonstrate that narrow-spire (“standard”) jets can have either a confined EMF, or a partially confined EMF where some of the cool minifilament leaks into the jet’s spire. Regarding EMF visibility: we find that in some cases the minifilament is apparent in as few as one of the four EUV channels we examined, being essentially invisible in the other channels; thus, it is necessary to examine images from multiple EUV channels before concluding that a jet does not have an EMF at its base. The sizes of the EMFs, measured projected against the sky and early in their eruption, is 14″ ± 7″, which is within a factor of 2 of other measured sizes of coronal-jet EMFs.

Solar Jets: SDO and IRIS Observations in the Perspective of New MHD Simulations

Solar jets are observed as collimated plasma beams over a large range of temperatures and wavelengths. They have been observed in H α and optical lines for more than 50 years and called surges. The term “jet” comes from X-ray observations after the launch of the Yohkoh satellite in 1991. They are the means of transporting energy through the heliosphere and participate to the corona heating and the acceleration of solar wind. Several characteristics have been derived about their velocities, their rates of occurrence, and their relationship with CMEs. However, the initiation mechanism of jets, e.g. emerging flux, flux cancellation, or twist, is still debated. In the last decade coordinated observations of the Interface Region Imaging Spectrograph (IRIS) with the instruments on board the Solar Dynamic Observatory (SDO) allow to make a step forward for understanding the trigger of jets and the relationship between hot jets and cool surges. We observe at the same time the development of 2D and 3D MHD numerical simulations to interpret the results. This paper summarizes recent studies of jets showing the loci of magnetic reconnection in null points or in bald patch regions forming a current sheet. In the pre-jet phase a twist is frequently detected by the existence of a mini filament close to the dome of emerging flux. The twist can also be transferred to the jet from a flux rope in the vicinity of the reconnection by slippage of the polarities. Bidirectional flows are detected at the reconnection sites. We show the role of magnetic currents detected in the footprints of flux rope and quasi-separatrix layers for initiating the jets. We select a few studies and show that with the same observations, different interpretations are possible based on different approaches e.g. non linear force free field extrapolation or 3D MHD simulation.

Homologous Accelerated Electron Beams, a Quasiperiodic Fast-propagating Wave, and a Coronal Mass Ejection Observed in One Fan-spine Jet

Abstract Using imaging and radio multi-wavelength observations, we studied the origin of two homologous accelerated electron beams and a quasiperiodic fast-propagating (QFP) wave train associated with a solar jet on 2012 July 14. The jet occurred in a small-scale fan-spine magnetic system embedded in a large-scale pseudostreamer associated with a GOES C1.4 flare, a jet-like coronal mass ejection (CME), a type II radio burst, and a type III radio burst. During the initial stage, a QFP wave train and a fast-moving on-disk radio source were detected in succession ahead of the jet along the outer spine of the fan-spine system. When the jet reached a height of about 1.3 solar radii, it underwent a bifurcation into two branches. Based on our analysis results, all the observed phenomena in association with the jet can be explained by using a fan-spine magnetic system. We propose that both the type III radio burst and the on-disk fast-moving radio source were caused by the same physical process, i.e., energetic electrons accelerated by magnetic reconnection at the null point, and these energetic electrons were propagating along the open field lines of the pseudostreamer and the closed outer spine of the fan-spine structure, respectively. Due to the bifurcation of the jet body, the lower branch along the closed outer spine of the fan-spine structure fell back to the solar surface, while the upper branch along the open field lines of the pseudostreamer caused the jet-like CME in the outer corona.

Solar jets observed with the Interface Region Imaging Spectrograph (IRIS)

Solar jets are impulsive, collimated plasma ejections that are triggered by magnetic reconnection. They are observed for many decades in various temperatures and wavelengths, therefore their kinematic characteristics, such as velocity and recurrence, have been extensively studied. Nevertheless, the high spatial resolution of the Interface Region Imaging Spectrograph (IRIS) launched in 2013 allowed us to make a step forward in the understanding of the relationship between surges and hot jets. In this paper we report on several results of recent studies of jets observed by IRIS. Cool and hot plasma have been detected with ejections of cool blobs having a speed reaching 300 km s−1 during the impulsive phase of jet formation and slow velocity surges surrounding hot jets after the reconnection phase. Plasma characteristics of solar jets, such as the emission measure, temperature, and density have been quantified. A multi-layer atmosphere at the reconnection site based on observed IRIS spectra has been proposed. IRIS evidenced bidirectional flows at reconnection sites, and tilt along the spectra which were interpreted as the signature of twist in jets. The search of possible sites for reconnection could be achieved by the analysis of magnetic topology. Combining Solar Dynamics Observatory/Helioseismic Magnetic Imager (SDO/HMI) vector magnetograms and IRIS observations, it was found that reconnection site could be located at null points in the corona as well as in bald patch regions low in the photosphere. In one case study a magnetic sketch could explain the initiation of a jet starting in a bald patch transformed to a current sheet in a dynamical way, and the transfer of twist from a flux rope to the jet during the magnetic reconnection process.

Reflection and Evolution of Torsional Alfvén Pulses in Zero-beta Flux Tubes

Abstract We model the behavior of a torsional Alfvén pulse, assumed to propagate through the chromosphere. Building on our existing model, we utilize the zero-beta approximation appropriate for plasma in an intense magnetic flux tube, e.g., a magnetic bright point. The model is adapted to investigate the connection between these features and chromospheric spicules. A pulse is introduced at the lower, photospheric boundary of the tube as a magnetic shear perturbation, and the resulting propagating Alfvén waves are reflected from an upper boundary, representing the change in density found at the transition region. The induced upward mass flux is followed by the reversal of the flux that may be identified with the rising and falling behavior of certain lower solar atmospheric jets. The ratio of the transmitted and reflected mass flux is estimated and compared with the relative total mass of spicules and the solar wind. An example is used to study the properties of the pulse. We also find that the interaction between the initial and reflected waves may create a localized flow that persists independently from the pulse itself.

Fifty Years of 3He-Rich Events

The early 1970s saw a new and surprising feature in the composition of solar energetic particles (SEPs), resonant enhancements up to 10,000-fold in the ratio 3He/4He that could even make 3He dominant over H in rare events. It was soon learned that these events also had enhancements in the abundances of heavier elements, such as a factor of ∼10 enhancements in Fe/O, which was later seen to be part of a smooth increase in enhancements vs. mass-to-charge ratio A/Q from H to Pb, rising by a factor of ∼1000. These events were also associated with streaming 10–100 keV electrons that produce type III radio bursts. In recent years we have found these “impulsive” SEP events to be accelerated in islands of magnetic reconnection from plasma temperatures of 2–3 MK on open field lines in solar jets. Similar reconnection on closed loops traps the energy of the particles to produce hot (>10 MK), bright flares. Sometimes impulsive SEP intensities are boosted by shock waves when the jets launch fast coronal mass ejections. No single theory yet explains both the sharp resonance in 3He and the smooth increase up to heavier elements; two processes seem to occur. Sometimes the efficient acceleration even exhausts the rare 3He in the source region, limiting its fluence.

How Negative Energy and Kelvin–Helmholtz Instabilities Grow by Longitudinal Waves in Solar Atmospheric Jets

Abstract We model the propagation of slow magnetoacoustic body waves in solar jets in the course of negative energy wave excitation in the context of magnetohydrodynamic theory. Explicit approximate expressions are provided for the dispersion relation of slow body waves, providing insight into the influence of the steady flow speed, radiative cooling, and plasma-β at a glance. Analytic expressions are provided regarding critical speeds in the presence of backward waves, negative energy wave speeds, and instabilities. The buildup of the Kelvin–Helmholtz instability above the negative energy wave instability is expressed through analytic expressions that provide insight into the interplay of equilibrium conditions and dispersive effects as they affect the instability growth rate of slow body waves at various altitudes. As slow magnetoacoustic waves propagate with the same speed in the long-wavelength limit, slow body kink waves experience stronger dispersion than sausage waves. Backward waves are also probable at lower steady flow speeds for medium wavelengths when the jet hosts slow body kink waves that provide greater domains for dissipative processes. Slow body sausage waves grow faster while nearing the long-wavelength limit, while the internal plasma-β decreases the instability growth rate. The seismological aspect is that energy transfer to the external medium is observed on various timescales. The observational aspect is that slow body kink waves may exist at higher altitudes as energy has already been extracted to the external medium due to negative energy unstable slow body sausage waves in earlier stages contributing toward coronal heating.

The Evolution of Research on Abundances of Solar Energetic Particles

Sixty years of study of energetic particle abundances have made a major contribution to our understanding of the physics of solar energetic particles (SEPs) or solar cosmic rays. An early surprise was the observation in small SEP events of huge enhancements in the isotope 3He from resonant wave–particle interactions, and the subsequent observation of accompanying enhancements of heavy ions, later found to increase 1000-fold as a steep power of the mass-to-charge ratio A/Q, right across the elements from H to Pb. These “impulsive” SEP events have been related to magnetic reconnection on open field lines in solar jets; similar processes occur on closed loops in flares, but those SEPs are trapped and dissipate their energy in heat and light. After early controversy, it was established that particles in the large “gradual” SEP events are accelerated at shock waves driven by wide, fast coronal mass ejections (CMEs) that expand broadly. On average, gradual SEP events give us a measure of element abundances in the solar corona, which differ from those in the photosphere as a classic function of the first ionization potential (FIP) of the elements, distinguishing ions and neutrals. Departures from the average in gradual SEPs are also power laws in A/Q, and fits of this dependence can determine Q values and thus estimate source plasma temperatures. Complications arise when shock waves reaccelerate residual ions from the impulsive events, but excess protons and the extent of abundance variations help to resolve these processes. Yet, specific questions about SEP abundances remain.

Numerical simulations of macrospicule jets under energy imbalance conditions in the solar atmosphere

ABSTRACT Using numerical simulations, we study the effects of thermal conduction and radiative cooling on the formation and evolution of solar jets with some macrospicules features. We initially assume that the solar atmosphere is rarely in equilibrium through energy imbalance. Therefore, we test whether the background flows resulting from an imbalance between thermal conduction and radiative cooling influence the jets’ behaviour. In this particular scenario, we trigger the formation of the jets by launching a vertical velocity pulse localized at the upper chromosphere for the following test cases: (i) adiabatic case; (ii) thermal conduction case; (iii) radiative cooling case; and (iv) thermal conduction + radiative cooling case. According to the test results, the addition of the thermal conduction results in smaller and hotter jets than in the adiabatic case. On the other hand, the radiative cooling dissipates the jet after reaching the maximum height (≈5.5 Mm), making it shorter and colder than in the adiabatic and thermal conduction cases. Besides, the flow generated by the radiative cooling is more substantial than that caused by the thermal conduction. Despite the energy imbalance of the solar atmosphere background, the simulated jet shows morphological features of macrospicules. Furthermore, the velocity pulse steepens into a shock that propagates upward into a solar corona that maintains its initial temperature. The shocks generate the jets with a quasi-periodical behaviour that follows a parabolic path on time–distance plots consistent with macrospicule jets’ observed dynamics.

What Causes Faint Solar Coronal Jets from Emerging Flux Regions in Coronal Holes?

Abstract Using EUV images and line-of-sight magnetograms from Solar Dynamics Observatory, we examine eight emerging bipolar magnetic regions (BMRs) in central-disk coronal holes for whether the emerging magnetic arch made any noticeable coronal jets directly, via reconnection with ambient open field as modeled by Yokoyama & Shibata. During emergence, each BMR produced no obvious EUV coronal jet of normal brightness, but each produced one or more faint EUV coronal jets that are discernible in AIA 193 Å images. The spires of these jets are much fainter and usually narrower than for typical EUV jets that have been observed to be produced by minifilament eruptions in quiet regions and coronal holes. For each of 26 faint jets from the eight emerging BMRs, we examine whether the faint spire was evidently made a la Yokoyama & Shibata. We find that (1) 16 of these faint spires evidently originate from sites of converging opposite-polarity magnetic flux and show base brightenings like those in minifilament-eruption-driven coronal jets, (2) the 10 other faint spires maybe were made by a burst of the external-magnetic-arcade-building reconnection of the emerging magnetic arch with the ambient open field, with reconnection directly driven by the arch's emergence, but (3) none were unambiguously made by such emergence-driven reconnection. Thus, for these eight emerging BMRs, the observations indicate that emergence-driven external reconnection of the emerging magnetic arch with ambient open field at most produces a jet spire that is much fainter than in previously reported, much more obvious coronal jets driven by minifilament eruptions.

Magnetohydrodynamic Simulations of Spicular Jet Propagation Applied to Lower Solar Atmosphere Model

Abstract We report a series of numerical experiments for the propagation of a momentum pulse representing a chromospheric jet, simulated using an idealized magnetohydrodynamic model. The jet in a stratified lower solar atmosphere is subjected to a varied initial driver (amplitude, period) and magnetic field conditions to examine the parameter influence over jet morphology and kinematics. The simulated jet captured key observed spicule characteristics including maximum heights, field-aligned mass motions/trajectories, and cross-sectional width deformations. Next, the jet features also show a prominent bright, bulb-like apex, similar to reported observed chromospheric jets, formed due to the higher density of plasma and/or waves. Furthermore, the simulations highlight the presence of not yet observed internal crisscross/knots substructures generated by shock waves reflected within the jet structure. Therefore we suggest verifying these predicted fine-scale structures in highly localized lower solar atmospheric jets, e.g., in spicules or fibrils by high-resolution observations, offered by the Daniel K. Inoyue Solar Telescope or otherwise.

Propagation of Torsional Alfvén Pulses in Zero-beta Flux Tubes

Abstract In this study, we investigate analytically the generation of mass flux due to a torsional Alfvén pulse. We derive that the presence of torsional Alfvén waves, which have been observed in, e.g., photospheric magnetic bright points (MBPs), can result in vertical plasma motions. The formation of this mass flux may even be a viable contribution to the generation of chromospheric mass transport, playing potential roles in the form of localized lower solar atmospheric jets. This relationship is studied using a flux tube model, with the waves introduced at the lower boundary of the tube as a magnetic shear perturbation. Due to the nature of MBPs we simplify the model by using the zero-beta approximation for the plasma inside the tube. The analytical results are demonstrated by an example of the type of Alfvén wave perturbation that one might expect to observe, and comparison is made with properties of spicules known from observations. We find that field-aligned plasma flux is formed nonlinearly as a result of the Lorentz force generated by the perturbations, and could be consistent with jet formation, although the current model is not intended to determine the entire evolution of a jet. Critical discussion of the model follows, including suggestions for improvements and for high-resolution proposed observations in order to constrain the driving magnetic and velocity shear.

The Photospheric Footpoints of Solar Coronal Hole Jets

Abstract We study the photospheric footpoints of a set of 35 coronal jets in a coronal hole as observed by Hinode/EIS. We use SDO/AIA data to coalign the spectroscopic EIS data with SDO/HMI line-of-sight magnetograms and calculate the plane-of-sky flow field using local correlation tracking (LCT) on SDO/HMI white light images. The jets are put into categories according to the changes observed in the photospheric magnetic flux at the footpoints of the coronal bright point where the jets originate: flux cancellation, complex flux changes (flux appearance/emergence and cancellation), and no flux changes. We also present three jets in detail. Observed magnetic flux evolution, LCT flow field structure and location of the jet footpoints at supergranular boundaries do not support the flux emergence scenario used in most jet simulations and are also not consistent with a rotational photospheric driver. Detailed numerical jet simulations using our observed photospheric features, in particular converging flows and flux cancellation do not currently exist, although such models would provide a realistic eruptive event scenario.

Observation and modelling of solar jets.

The solar atmosphere is full of complicated transients manifesting the reconfiguration of the solar magnetic field and plasma. Solar jets represent collimated, beam-like plasma ejections; they are ubiquitous in the solar atmosphere and important for our understanding of solar activities at different scales, the magnetic reconnection process, particle acceleration, coronal heating, solar wind acceleration, as well as other related phenomena. Recent high-spatio-temporal-resolution, wide-temperature coverage and spectroscopic and stereoscopic observations taken by ground-based and space-borne solar telescopes have revealed many valuable new clues to restrict the development of theoretical models. This review aims at providing the reader with the main observational characteristics of solar jets, physical interpretations and models, as well as unsolved outstanding questions in future studies.

Temperature in Solar Sources of 3He-rich Solar Energetic Particles and Relation to Ion Abundances

Abstract 3He-rich solar energetic particles (SEPs) are believed to be accelerated in solar flares or jets by a mechanism that depends on the ion charge-to-mass (Q/M) ratio. It implies that the flare plasma characteristics (e.g., temperature) may be effective in determining the elemental abundances of 3He-rich SEPs. This study examines the relation between the suprathermal (≲0.2 MeV nucleon−1) abundances of the He–Fe ions measured on the Advanced Composition Explorer and temperature in the solar sources for 24 3He-rich SEP events in the period 2010–2015. The differential emission measure technique is applied to derive the temperature of the source regions from the extreme ultraviolet imaging observations on the Solar Dynamics Observatory. The obtained temperature distribution peaks at 2.0–2.5 MK that is surprisingly consistent with earlier findings based on in situ elemental abundance or charge state measurements. We have found a significant anticorrelation between 3He/4He ratio and solar source temperature with a coefficient −0.6. It is most likely caused by non-charge-stripping processes, as both isotopes would be fully ionized in the inferred temperature range. This study shows that the elemental ratios 4He/O, N/O, Ne/O, Si/O, S/O, Ca/O, Fe/O generally behave with temperature as expected from abundance enhancement calculations at ionization equilibrium. The C and Mg, the two species with small changes in the Q/M ratio in the obtained temperature range, show no such behavior with temperature and could be influenced by similar processes as for the 3He/4He ratio.

Torsional Alfvén Wave Cascade and Shocks Evolving in Solar Jets

Abstract The aim of this study is to model the nature of nonlinear torsional magnetohydrodynamic waves propagating in solar jets as they are elevated to the outer solar atmosphere. The contribution of sequential processes to the transfer of energy is taken under consideration: the nonlinear cascade and shock formation. Thus a straight magnetic cylinder embedded in a plasma with an initial magnetic field and parallel flow to the cylinder axis is implemented. To resemble a jet where the oscillation wavelength highly exceeds the radius, the second-order thin flux tube approximation proves adequate. A Cohen–Kulsrud type equation is presented, and its solution highly depends on the parameter presented in this study, which itself is constituted of various environmental and equilibrium conditions that affect the perturbations of the variables as well as the nonlinear forces connected to Alfvén wave propagation. The shock formation time of torsional waves is inversely proportional to the density contrast of the jet, while the efficiency of energy transfer to shorter scales is directly proportional to the density contrast. While the parallel flow with a shear at the boundary expedites shock formation, its efficiency regarding energy transfer is dramatically enhanced by the plasma-β, significantly contributing to coronal heating. The observational and seismological aspect of the present study is that faster jets are less probable for observations at higher altitudes, as they experience energy transfer mostly at the base of the corona, while slow speed jets may be observed at higher altitudes contributing to solar wind acceleration.

On the Correlation between Energy Spectra and Element Abundances in Solar Energetic Particles

In solar energetic particle (SEP) events, the physical processes of both shock acceleration and scattering during transport can cause energy-spectral indices to be correlated with enhancement or suppression of element abundances versus mass-to-charge ratios A/Q. We observe correlations for those “gradual” SEP events where shock waves accelerate ions from the ambient coronal plasma, but there are no such correlations for “impulsive” SEP events produced by magnetic reconnection in solar jets, where abundance enhancement in different events vary from (A/Q)^{+2} to (A/Q)^{+8}, nor are there correlations when shock waves reaccelerate these residual impulsive ions. In the latter events the abundances are determined separately, prior to the accelerated spectra. Events with correlated spectra and abundances show a wide variety of interesting behavior that has not been described previously. Small and moderate gradual SEP events, with relative abundances typically depending approximately upon (A/Q)^{-1} and the spectra upon energy E^{-2.5}, vary little with time. Large SEP events show huge temporal variations skirting the correlation line; in one case O spectra vary with time from E^{-1} to E^{-5} while abundances vary from (A/Q)^{+1} to (A/Q)^{-2} during the event. In very large events, streaming-limited transport through proton-generated resonant Alfvén waves flattens the spectra and enhances heavy ion abundances prior to local shock passage, then steepens the spectra and reduces enhancements afterward, recapturing the typical correlation. Systematic correlation of spectra and element abundances provide a new perspective on the “injection problem” of ion selection by shocks and on the physics of SEP acceleration and transport.

Thermal conduction effects on formation of chromospheric solar tadpole-like jets

ABSTRACT We measure the effects of non-isotropic thermal conduction on generation of solar chromospheric jets through numerical simulations carried out with the use of one fluid magnetohydrodynamics (MHD) code magnus. Following the work of Srivastava et al. (2018), we consider the atmospheric state with a realistic temperature model and generate the ejection of plasma through a gas pressure driver operating in the top chromosphere. We consider the magnetic field mimicking a flux tube and perform parametric studies by varying the magnetic field strength and the amplitude of the driver. We find that in the case of thermal conduction the triggered jets exhibit a considerably larger energy and mass fluxes and their shapes are more collimated and penetrate more the solar corona than for the ideal MHD equations. Low magnetic fields allow these jets to be more energetic, and larger magnetic fields decrease the enhancement of mass and energy due to the inclusion of the thermal conductivity.

The role of small-scale surface motions in the transfer of twist to a solar jet from a remote stable flux rope

Context. Jets often have a helical structure containing ejected plasma that is both hot and also cooler and denser than the corona. Various mechanisms have been proposed to explain how jets are triggered, primarily attributed to a magnetic reconnection between the emergence of magnetic flux and environment or that of twisted photospheric motions that bring the system into a state of instability. Aims. Multi-wavelength observations of a twisted jet observed with the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory and the Interface Region Imaging Spectrograph (IRIS) were used to understand how the twist was injected into the jet, thanks to the IRIS spectrographic slit fortuitously crossing the reconnection site at that time. Methods. We followed the magnetic history of the active region based on the analysis of the Helioseismic and Magnetic Imager vector magnetic field computed with the UNNOFIT code. The nature and dynamics of the jet reconnection site are characterised by the IRIS spectra. Results. This region is the result of the collapse of two emerging magnetic fluxes (EMFs) overlaid by arch filament systems that have been well-observed with AIA, IRIS, and the New Vacuum Solar Telescope in Hα. In the magnetic field maps, we found evidence of the pattern of a long sigmoidal flux rope (FR) along the polarity inversion line between the two EMFs, which is the site of the reconnection. Before the jet, an extension of the FR was present and a part of it was detached and formed a small bipole with a bald patch (BP) region, which dynamically became an X-current sheet over the dome of one EMF where the reconnection took place. At the time of the reconnection, the Mg II spectra exhibited a strong extension of the blue wing that is decreasing over a distance of 10 Mm (from −300 km s−1 to a few km s−1). This is the signature of the transfer of the twist to the jet. Conclusions. A comparison with numerical magnetohydrodynamics simulations confirms the existence of the long FR. We conjecture that there is a transfer of twist to the jet during the extension of the FR to the reconnection site without FR eruption. The reconnection would start in the low atmosphere in the BP reconnection region and extend at an X-point along the current sheet formed above.

Cause and Kinematics of a Jetlike CME

Abstract In this article, we present the multiviewpoint and multiwavelength analysis of an atypical solar jet based on data from Solar Dynamics Observatory, SOlar and Heliospheric Observatory, and Solar TErrestrial RElations Observatory. It is generally believed that coronal mass ejections (CMEs) develop from the large-scale solar eruptions in the lower atmosphere. However, the kinematical and spatial evolution of the jet on 2013 April 28 suggests that the jet was clearly associated with a narrow CME with a width of ≈25° and speed of ≈450 km s−1. To better understand the link between the jet and the CME, we performed a coronal potential field extrapolation from the line-of-sight magnetogram of the active region. The extrapolations suggest that the jet eruption follows the same path of the open magnetic field lines from the source region, which provides a route for the jet material to escape from the solar surface toward the outer corona.