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تسجيل مستخدم جديدتضبيط الإلكترون اللاندو للأمواج الألففين الحركية في التربولنس المحاكاة لمغناطيس الجزء الخارجي
Electron Landau Damping of Kinetic Alfven Waves in Simulated Magnetosheath Turbulence
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تعتقد أن التضخم يلعب دورا في تسخين بلازما الرياح الشمسية، على الرغم من أن العديد من الأسئلة لا تزال متبقية لحلها بشأن طبيعة دقيقة للعوامل القادرة على تحقيق هذا العمل في الهيليوسفير. وخصوصا في الفيزياء الخاصة بالتفاعلات بين الجسيمات والحقول الكهرومغناطيسية التضخمية في مدى التضخم الذي ينتج عنه الضخامة، يبقى ناقصا مفهوما. وقد تم التحليل الأخير لفترة من تلك الملاحظات المتعددة المقياس (MMS) لاستخدام تقنية الارتباط بين الحقل والجسيم لإثبات أن التخمين اللانداو للإلكترون يشمل في ضخامة التضخم في حافظة المغناطيس الأرضية. وباستحثاط من هذا الاكتشاف، نحن نؤدي تحليلا رقميا بدقة عالية للتضخم في فترة MMS للتحقيق في دور التخمين اللانداو للإلكترون في ضخامة الطاقة التضخمية. ونحن نستخدم تقنية الارتباط بين الحقل والجسيم على بيانات المحاكاة الخاصة بنا، ونقارن نتائجنا بالإشارات المعروفة في الفضاء السرعة للتخمين اللانداو خارج مدى الضخامة، ونقيم الطاقة الإلكترونية النهائية. ونجد توافقا مشبها بين النتائج الرقمية والملاحظاتية لبعض النقاط الرئيسية من الطاقة ونتخيل طبيعة الاختلافات في الضوء من العوامل التجريبية، مثل الاختلافات في الدقة، ومن الإشارات المتطورة بشأن طبيعة التفاعلات بين الحقل والجسيم في وجود الموجات الألففين الكينيتية المبعثرة.
Turbulence is thought to play a role in the heating of the solar wind plasma, though many questions remain to be solved regarding the exact nature of the mechanisms driving this process in the heliosphere. In particular, the physics of the collisionless interactions between particles and turbulent electromagnetic fields in the kinetic dissipation range of the turbulent cascade remains incompletely understood. A recent analysis of an interval of Magnetosphere Multiscale (MMS) observations has used the field-particle correlation technique to demonstrate that electron Landau damping is involved in the dissipation of turbulence in the Earths magnetosheath. Motivated by this discovery, we perform a high-resolution gyrokinetic numerical simulation of the turbulence in the MMS interval to investigate the role of electron Landau damping in the dissipation of turbulent energy. We employ the field-particle correlation technique on our simulation data, compare our results to the known velocity-space signatures of Landau damping outside the dissipation range, and evaluate the net electron energization. We find qualitative agreement between the numerical and observational results for some key aspects of the energization and speculate on the nature of disagreements in light of experimental factors, such as differences in resolution, and of developing insights into the nature of field-particle interactions in the presence of dispersive kinetic Alfven waves.
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