Contributions to Plasma Physics最新文献

{"title":"Impact of multifold magnetic structure on spectroscopy analysis in Heliotron J based on EMC3-EIRENE simulation","authors":"F. Cai,&nbsp;S. Kado,&nbsp;G. Kawamura,&nbsp;C. Feng,&nbsp;R. Matoike,&nbsp;A. Miyashita,&nbsp;S. Ohshima,&nbsp;T. Minami,&nbsp;S. Inagaki,&nbsp;F. Kin,&nbsp;S. Kobayashi,&nbsp;A. Ishizawa,&nbsp;Y. Nakamura,&nbsp;H. Okada,&nbsp;S. Konoshima,&nbsp;T. Mizuuchi,&nbsp;Y. Feng,&nbsp;H. Frerichs,&nbsp;K. Nagasaki","doi":"10.1002/ctpp.202300145","DOIUrl":"10.1002/ctpp.202300145","url":null,"abstract":"<p>The distribution pattern of the connection length in the divertor region of Heliotron J was calculated by the field line tracing method. A multifold layer structure, characterized by the range of connection length, was revealed to interpret the response of the transport of the lower-charged impurity ions to the divertor structure. Impurity transport simulated by the EMC3-EIRENE code shows that lower-charged impurity ions tend to concentrate in the first multifold layer. This result is consistent with the line-integral extreme ultraviolet spectroscopy measurement, which implies that the impurity's response to the divertor topological structure needs to be considered in interpreting the spectroscopy result.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 7-8","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ctpp.202300145","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear oscillations of dust-acoustic waves in non-Maxwellian dusty plasma under the gravitational force effect","authors":"Rachid Fermous,&nbsp;Moufida Benzekka,&nbsp;Rabia Amour,&nbsp;Rima Mebrek","doi":"10.1002/ctpp.202300170","DOIUrl":"10.1002/ctpp.202300170","url":null,"abstract":"<p>In this paper, the role of dust grain's gravitational force on the nonlinear dust-acoustic oscillations in non-Maxwellian dusty plasma is analyzed. It is shown that increasing the number of non-thermal ions causes the diminution of the electrostatic potential's amplitude and a reduction in the number of oscillations introduced by the gravitational force. We have also found that reducing the size of the dust grain induces qualitatively the same effects as an increase in the number of non-thermal ions and when the gravitational force is considered, the electric charge exhibits oscillatory profile and becomes less negative far away from the origin. This result may be interesting in the study of astrophysical plasmas where the electromagnetic force is smaller than the gravitational one such as in the Halley Comet.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 9","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase separations of strongly coupled fine particles and fine particle mixtures in plasmas","authors":"Hiroo Totsuji","doi":"10.1002/ctpp.202400011","DOIUrl":"10.1002/ctpp.202400011","url":null,"abstract":"<p>Phase separations in strongly coupled fine particles in plasmas are discussed and two-component mixtures are simulated by molecular dynamics with the background plasma being treated as continuum. The system size of laboratory experiments is assumed and separations into phases with a common electron density of the background plasma are analyzed. Since the charge on fine particles increases approximately in proportion to the size, we expect the larger component with stronger coupling condensates from the mixture. Results expressed in terms of strengths of Coulomb coupling and screening of the larger component seem to be mostly similar to the one-component case, at least in cases where the ratio of fine particle sizes is 2, and the mixing ratio is in the range from 0.25 to 0.75.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 6","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Small amplitude solitary electron acoustic wave for hot electrons taking regularized kappa distribution","authors":"Yong Liu,&nbsp;Meng–Lei Wang","doi":"10.1002/ctpp.202400009","DOIUrl":"10.1002/ctpp.202400009","url":null,"abstract":"<p>The properties of small-amplitude solitary electron acoustic waves in a plasma where the hot electrons take regularized kappa distribution are investigated via the reductive perturbation method. It is found there only exists the sup-electron-acoustic rarefactive soliton, the electron acoustic velocity is modified by the regularized kappa distribution. The amplitude and width of the electron acoustic soliton decrease monotonously with the increase of the exponential cutoff parameter of hot electrons. But they vary with respect to the spectral index non-monotonously. As to the observed parameters in the Earth's inner magnetosphere, the speed, electric field strength, and the width of solitary electron acoustic wave are comparable with the observations.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 10","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of the scrape-off layer two-point model for deuterium and helium plasmas in JET ITER-like wall low-confinement plasma conditions","authors":"David Rees,&nbsp;Joona Sissonen,&nbsp;Mathias Groth,&nbsp;Vesa-Pekka Rikala,&nbsp;Henri Kumpulainen,&nbsp;Beth Thomas,&nbsp;Mathias Brix,&nbsp;JET Contributors","doi":"10.1002/ctpp.202300108","DOIUrl":"10.1002/ctpp.202300108","url":null,"abstract":"<p>The hydrogenic two-point model (H-2PM), an analytical model for the scrape-off layer that predicts a common electron and ion temperature and density along a flux tube from a target temperature and density, is adapted to a single-species helium (He) model, preserving the 2PM assumptions and analytical nature. Across a range of densities and heating powers, the predicted <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>T</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {T}_e $$</annotation>\u0000 </semantics></math> is within <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>20</mn>\u0000 <mspace></mspace>\u0000 <mi>eV</mi>\u0000 </mrow>\u0000 <annotation>$$ 20kern0.3em mathrm{eV} $$</annotation>\u0000 </semantics></math> of upstream measurements by high-resolution Thomson scattering (HRTS) for low-confinement He plasmas performed in JET ITER-like wall (JET-ILW). For high-recycling conditions, He-2PM predictions of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>n</mi>\u0000 <mi>e</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {n}_e $$</annotation>\u0000 </semantics></math> were within 10% of the Li-beam diagnostic measurements, excluding the near-SOL, when assuming <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>Z</mi>\u0000 <mi>eff</mi>\u0000 </msub>\u0000 <mo>=</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 <annotation>$$ {Z}_{mathrm{eff}}=1 $$</annotation>\u0000 </semantics></math>, suggesting the divertor SOL was not fully ionised in the JET-ILW He plasmas.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 7-8","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ctpp.202300108","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Instability analysis and face-to-face collision of dust acoustic waves in dusty plasmas: Perspective Jupiter environment","authors":"Umma Imon,&nbsp;M. S. Alam","doi":"10.1002/ctpp.202300119","DOIUrl":"10.1002/ctpp.202300119","url":null,"abstract":"<p>The collisionless unmagnetized five components dusty plasmas have been considered to study the significance of the face-to-face collision of single- and multi-solitons, phase shifts due to face-to-face collision, and instability of the dust acoustic waves in Jupiter's environment. To study the consequence of face-to-face collision extended Poincaré–Lighthill–Kuo method is used to derive the two-sided nonlinear Korteweg–De Vries (KdV) equation. Besides, to investigate the dust acoustic wave's instability, the nonlinear Schrödinger equation has been derived following the procedure of Slathia et al. The multi-soliton solutions are determined by employing the Hirota bilinear method. The concerned parameters in the issue play a crucial role in the phase shift (generated by the face-to-face collision); the collisional process of single-, double-, triple-, and quadruple-soliton; and the generation of dust acoustic solitons. Furthermore, the plasma parameters are crucial in the formation of dark solitons and envelop shocks.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 10","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an implicit electromagnetic capability for a hybrid gyrokinetic ion-fluid electron model","authors":"Mikhail Dorf,&nbsp;Milo Dorr,&nbsp;Debojyoti Ghosh","doi":"10.1002/ctpp.202300114","DOIUrl":"10.1002/ctpp.202300114","url":null,"abstract":"<p>We report on the development and implementation of a hybrid kinetic ion–fluid electron model for electromagnetic COGENT simulations of edge plasmas. COGENT is a finite-volume gyrokinetic code that employs a locally field-aligned coordinate system combined with a mapped multi-block grid technology to handle strongly anisotropic edge plasma turbulence. The simulation model involves the long-wavelength limit of the ion gyrokinetic equation coupled to the vorticity and Ohm's law equations for the electromagnetic field perturbations. In order to handle the fast Alfvén wave time scales, an implicit-explicit time integration approach with a physics-based preconditioner is used. The model is successfully applied to the simulations of ion-scale resistive-drift ballooning turbulence in a toroidal annulus geometry. Substantial speed-up over a fully explicit time integration approach is observed.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 7-8","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THz generation and spatiotemporal variation of two cross-focused Gaussian laser pulses in plasma","authors":"M. R. Jafari Milani","doi":"10.1002/ctpp.202400001","DOIUrl":"10.1002/ctpp.202400001","url":null,"abstract":"<p>The impact of spatial and temporal evolution of nonlinear mixing of two Gaussian laser pulses propagating in plasma on generation of terahertz (THz) radiation have been investigated taking into account the ponderomotive nonlinearity. By calculating the modified electron density of plasma caused by the finite ponderomotive force of the pump lasers and using wave equation and paraxial ray approximation, two coupled governing equations for temporal and spatial pulse-width parameters have been derived. The electric field of the THz wave as a result of nonlinear current density induced by the beat ponderomotive force of the pulses was extracted. Combined effects of initial laser and plasma parameters on the behavior of self-compression and self-focusing as well as THz radiation generation were investigated. The numerical results indicated a considerable spatiotemporal compression takes place within a specific range of laser intensity, exhibiting a saturation intensity point where the compression process reaches its maximum extent. It is observed that the generated THz radiation also strongly depends on the spatiotemporal dynamics of the pump pulses. The maximum THz amplitude corresponds to the strongest pump pulse compression extent.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 9","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studies on the spatial evolution of pulsed helium plasma","authors":"S. Singha,&nbsp;A. Ahmed,&nbsp;S. Borthakur,&nbsp;N. K. Neog,&nbsp;T. K. Borthakur","doi":"10.1002/ctpp.202400017","DOIUrl":"10.1002/ctpp.202400017","url":null,"abstract":"<p>The high-density transient plasma, streaming from a pulsed plasma accelerator (PPA), was diagnosed with a Triple Langmuir probe (TLP) for spatial mapping of the stream in terms of plasma density and temperature. A contour plot for density and temperature shows a distinct form of a highly dense island of plasma with varied plasma temperatures. The formation of such highly dense islands can be correlated with the formation of distinct plasma structures, as observed in astrophysical plasmas and fusion plasma. The results of TLP were supported by the intensity variation derived from signals of a photodetector system. The plasma stream imaged with high-speed video camera also showed the density fluctuation inside the plasma stream. The estimated maximum density and temperature were ∼7.2 × 10²⁰ m⁻³ and ∼28 eV, respectively.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 9","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140598178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental investigation on the rock breaking mechanism of electrode bit by high-voltage electric pulses","authors":"Weiji Liu,&nbsp;Youjian Zhang,&nbsp;Xiaohua Zhu,&nbsp;Hai Hu","doi":"10.1002/ctpp.202300182","DOIUrl":"10.1002/ctpp.202300182","url":null,"abstract":"<p>Because of the low rate of penetration (ROP) and high cost of traditional rotary rock breaking, it is important to explore some unconventional new rock breaking methods. High-voltage electrical pulse (HVEP) drilling has attracted much attention because of its advantages such as environmental protection, good borehole wall quality, and high rock breaking efficiency. This paper independently designs and builds a complete indoor experimental platform of HVEP electric breakdown, and selects the self-designed classic coaxial type and cross-type electrode bits to carry out laboratory experiments of HVEP rock-breaking, to truly reveal the rock breaking mechanism of HVEP drilling and further promote its industrial application. The influence of the anode structure of electrode bit, liquid insulation medium, drilling fluid circulation condition, and pulse voltage on rock breaking mechanism are investigated. The findings indicate that the bottom-hole morphology of the rock sample is related to the electrode bit structure. The S-type electrode bit has a certain discharge blind area, which is not conducive to the rock breaking of HVEP. With the increase of pre-charging voltage, the effective discharge rate (EDR) of both electrode bits increases gradually, trending towards 100% as the pre-charging voltage grows. Under non-circulating working conditions, greater conductivity of liquid medium results in a lower EDR of electrode bits. In all kinds of liquid media, under low voltage (pre-charging voltage &lt;15 kV), the single pulse penetration depth (SPPD) under the non-circulating working condition is larger than that of the circulating condition, in contrast, at a higher voltage (pre-charging voltage &gt;15 kV), the SPPD under the circulating condition is larger than that the non-circulating condition. To further observe the generation of plasma channel and the rock damage characterization of HVEP, this paper also establishes a three-dimensional numerical model of dynamic electrical breakdown of red sandstone to reproduce the generation of plasma channel, which can be mutually confirmed by indoor experimental results. The research results are essential for a deeper understanding of the rock breaking mechanism by electric pulse and for providing some theoretical guidance for the industrial application of electric pulse drilling technology.</p>","PeriodicalId":10700,"journal":{"name":"Contributions to Plasma Physics","volume":"64 9","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140359091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}