Multi-Wavelength Spectroscopic Observation of Extreme-Ultraviolet Jet in Ar 10960

Matsui, Yutaka; Yokoyama, T.; Kitagawa, N.; Imada, Shinsuke

doi:10.1088/0004-637x/759/1/15

Cited by 19 publications

(29 citation statements)

References 34 publications

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“…In the evaporation model, the energy released by reconnection impulsively heats the plasma in both closed and open magnetic flux tubes formed by reconnection. On closed field lines, the resulting density increase produces enhanced EUV and soft X-ray emission, while on open flux tubes, the strong pressure and temperature gradients induce an evaporation upflow (e.g., Shimojo et al 2001;Miyagoshi & Yokoyama 2003;Miyagoshi et al 2006;Matsui et al 2012). These pressure-driven upflows are much slower than those driven by tension or untwisting: evaporation is at most transonic, while tension and untwisting drive Alfvénic flows.…”

Section: Introductionmentioning

confidence: 99%

“…Therefore, we focus on the physics of the tension-driven model and the untwisting model in the present study. While the evaporation model may explain some of the emission from coronal jets (Shimojo et al 2001;Matsui et al 2012), it is predominantly driven thermodynamically and not magnetically, and hence only indirectly relevant to our theme of reconnection-driven jets.…”

Section: Introductionmentioning

confidence: 99%

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Model for straight and helical solar jets

Pariat

Dalmasse

DeVore

et al. 2015

A&A

127

148

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Context. Jets are dynamic, impulsive, well-collimated plasma events developing at many different scales and in different layers of the solar atmosphere. Aims. Jets are believed to be induced by magnetic reconnection, a process central to many astrophysical phenomena. Studying their dynamics can help us to better understand the processes acting in larger eruptive events (e.g., flares and coronal mass ejections) as well as mass, magnetic helicity, and energy transfer at all scales in the solar atmosphere. The relative simplicity of their magnetic geometry and topology, compared with larger solar active events, makes jets ideal candidates for studying the fundamental role of reconnection in energetic events. Methods. In this study, using our recently developed numerical solver ARMS, we present several parametric studies of a 3D numerical magneto-hydrodynamic model of solar-jet-like events. We studied the impact of the magnetic field inclination and photospheric field distribution on the generation and properties of two morphologically different types of solar jets, straight and helical, which can account for the observed so-called standard and blowout jets. Results. Our parametric studies validate our model of jets for different geometric properties of the magnetic configuration. We find that a helical jet is always triggered for the range of parameters we tested. This demonstrates that the 3D magnetic null-point configuration is a very robust structure for the energy storage and impulsive release characteristic of helical jets. In certain regimes determined by magnetic geometry, a straight jet precedes the onset of a helical jet. We show that the reconnection occurring during the straight-jet phase influences the triggering of the helical jet. Conclusions. Our results allow us to better understand the energization, triggering, and driving processes of straight and helical jets. Our model predicts the impulsiveness and energetics of jets in terms of the surrounding magnetic field configuration. Finally, we discuss the interpretation of the observationally defined standard and blowout jets in the context of our model, as well as the physical factors that determine which type of jet will occur.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Model for straight and helical solar jets

Pariat

Dalmasse

DeVore

et al. 2015

A&A

127

148

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“…The temperatures of jets have been studied by using two techniques that are based on different approaches -the filter-ratio method which assumes a single temperature along the line of sight (LOS; e.g., Shimojo & Shibata 2000;Nisticò et al 2011;Madjarska 2011;Madjarska et al 2012;Matsui et al 2012;Pucci et al 2013;Young & Muglach 2014a) and the differential emission measure (DEM) method which assumes a multi-thermal plasma along the LOS (e.g., Doschek et al 2010;Chandrashekhar et al 2014;Kayshap et al 2013;Chen et al 2013;Sun et al 2014). Nisticò et al (2011) report the temperature of CH jets as ranging from 0.8 to 1.3 MK using the filter-ratio method applied to STEREO/SECCHI data; whereas Pucci et al (2013) find the temperature of the jet to be 1.7 MK.…”

Section: Introductionmentioning

confidence: 99%

“…The authors also measured the electron density in the high velocity up-flow component using the Fe XII line ratios and find them to be above log N e (cm −3 ) = 11. Matsui et al (2012) studied the relationship between the velocity and temperature of an AR jet using EIS and STEREO observations. The authors observed the jet structure over a wide temperature range from log T [K] = 4.9 to 6.4 and investigated the doppler velocities.…”

Section: Introductionmentioning

confidence: 99%

Multiwavelength study of 20 jets that emanate from the periphery of active regions

Mulay

Tripathi

Zanna

et al. 2016

A&A

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Aims. We present a multiwavelength analysis of 20 EUV jets which occurred at the periphery of active regions close to sunspots. We discuss the physical parameters of the jets and their relation with other phenomena such as Hα surges, nonthermal type-III radio bursts and hard X-ray (HXR) emission. Methods. These jets were observed between August 2010 and June 2013 by the Atmospheric Imaging Assembly (AIA) instrument that is onboard the Solar Dynamic Observatory (SDO). We selected events that were observed on the solar disk within +/-60• latitude. Using AIA wavelength channels that are sensitive to coronal temperatures, we studied the temperature distribution in the jets using the line of sight (LOS) differential emission measure (DEM) technique. We also investigated the role of the photospheric magnetic field using the LOS magnetogram data from the Helioseismic and Magnetic Imager (HMI) onboard SDO. Results. It has been observed that most of the jets originated from the western periphery of active regions. Their lifetimes range from 5 to 39 min with an average of 18 min and their velocities range from 87 to 532 km s −1 with an average of 271 km s −1 . All the jets are co-temporally associated with Hα surges. Most of the jets are co-temporal with nonthermal type-III radio bursts observed by the Wind/WAVES spacecraft in the frequency range from 20 kHz to 13 MHz. We confirm the source region of these bursts using the potential field source surface (PFSS) technique. Using Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations, we found that half of the jets produced HXR emission and they often shared the same source region as the HXR emission (6−12 keV). Ten out of 20 events showed that the jets originated in a region of flux cancellation and six jets in a region of flux emergence. Four events showed flux emergence and then cancellation during the jet evolution. DEM analyses showed that for most of the spires of the jets, the DEM peaked at around log T [K] = 6.2/6.3 (∼2 MK). In addition, we derived an emission measure and a lower limit of electron density at the location of the spire (jet 1: log EM = 28.6, N e = 1.3 × 10 10 cm −3 ; jet 2: log EM = 28.0, N e = 8.6 × 10 9 cm −3 ) and the footpoint (jet 1 -log EM = 28.6, N e = 1.1 × 10 10 cm −3 ; jet 2: log EM = 28.1, N e = 8.4 × 10 9 cm −3 ). These results are in agreement with those obtained earlier by studying individual active region jets. Conclusions. The observation of flux cancellation, the association with HXR emission and emission of nonthermal type-III radio bursts, suggest that the initiation and therefore, heating is taking place at the base of the jet. This is also supported by the high temperature plasma revealed by the DEM analysis in the jet footpoint (peak in the DEM at log T [K] = 6.5). Our results provide substantial constraints for theoretical modeling of the jets and their thermodynamic nature.

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“…One is filter-ratio assuming single temperature along the line-of-sight (LOS). It has been applied using the EUV 171 Å, 195 Å, and 284 Å filters or broadband soft X-ray filters (e.g., Shimojo & Shibata 2000;Nisticò et al 2011;Madjarska 2011;Madjarska et al 2012;Matsui et al 2012;Pucci et al 2013;Young & Muglach 2014). This approach, however, has its limitations and weaknesses.…”

Section: Introductionmentioning

confidence: 99%

Blobs in recurring extreme-ultraviolet jets

Zhang

2014

A&A

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Context. Coronal jets are one type of ubiquitous small-scale activity that is caused by magnetic reconnection in the solar corona. They are often associated with cool surges in the chromosphere. Aims. In this paper, we report our discovery of blobs in the recurrent and homologous jets that occurred at the western edge of the NOAA active region 11259 on 2011 July 22. Methods. The jets were observed in the seven extreme-ultraviolet (EUV) filters of the Atmospheric Imaging Assembly instrument aboard the Solar Dynamics Observatory. Using the base-difference images of the six filters (94, 131, 171, 211, 193, and 335 Å), we carried out the differential emission measure (DEM) analyses to explore the thermodynamic evolutions of the jets. The jets were accompanied by cool surges observed in the Hα line center of the ground-based telescope in the Big Bear Solar Observatory. Results. The jets that had lifetimes of 20−30 min recurred at the same place for three times with an interval of 40−45 min. Interestingly, each of the jets intermittently experienced several upward eruptions at the speed of 120−450 km s −1 . After reaching the maximum heights, they returned back to the solar surface, showing near-parabolic trajectories. The falling phases were more evident in the low-T filters than in the high-T filters, indicating that the jets experienced cooling after the onset of eruptions. We identified bright and compact blobs in the jets during their rising phases. The simultaneous presence of blobs in all the EUV filters were consistent with the broad ranges of the DEM profiles of the blobs (5.5 ≤ log T ≤ 7.5), indicating their multi-thermal nature. The median temperatures of the blobs were ∼2.3 MK. The blobs that were ∼3 Mm in diameter had lifetimes of 24−60 s. Conclusions. To our knowledge, this is the first report of blobs in coronal jets. We propose that these blobs are plasmoids created by the magnetic reconnection as a result of tearing-mode instability and are ejected out along the jets.

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Multi-Wavelength Spectroscopic Observation of Extreme-Ultraviolet Jet in Ar 10960

Cited by 19 publications

References 34 publications

Model for straight and helical solar jets

Model for straight and helical solar jets

Multiwavelength study of 20 jets that emanate from the periphery of active regions

Blobs in recurring extreme-ultraviolet jets

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