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تسجيل مستخدم جديدأشعة إكس ذات طاقة عالية من J174545.5-285829، الكرة المدفعية: نبئ نبئ الريح النبئية المتوقعة مرتبطة بسجر أ شرق
High-Energy X-rays from J174545.5-285829, the Cannonball: A Candidate Pulsar Wind Nebula Associated with Sgr A East
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نحن نقدم الكشف بشكل صريح للإشعاع الغير حراري حتى 30 كيلو فولت من الكانون بول، وهو ظهور إشعاعي متجمع على عدد قليل من الأقدام بالقرب من مركز المجرة، باستخدام مقطع نوستار الإشعاعي. الكانون بول هو مركب نبطي كبير السرعة (vproj~500 كم / ث) مع نبطية ريح النبط القطبية (PWN) الموجودة على بعد ~2 شمال شرق من Sgr A *، خارج غطاء الراديو لمؤثر النيزك الشهير سجيتاريوس A (Sgr A) الشرقي. طيف الإشعاع الغير حراري الذي قيس حتى 30 كيلو فولت يتم تحديده بشكل جيد بواسطة قوة Gamma ~ 1.6، وهو عادي ل PWN، ولديه لومينوسية الإشعاع 3-30 كيلو فولت = 1.3e34 إرج / ث. يشير النتائج الطيفية والمكانية التي تم الحصول عليها من البيانات الإشعاعية والراديو بشكل قوي إلى نبطي هارب نشط نشأ في حدث Sgr A East النيزك. لم نجد أي إشارة مضطربة من الكانون بول. تسمح المقاطع النوستار لنا بإخلاء الحكم على مجال المغناطيسي ل PWN وتظهر أنه يتوافق مع الحد الأدنى الذي تم الحصول عليه من الملاحظات الراديو.
We report the unambiguous detection of non-thermal X-ray emission up to 30 keV from the Cannonball, a few-arcsecond long diffuse X-ray feature near the Galactic Center, using the NuSTAR X-ray observatory. The Cannonball is a high-velocity (vproj~500 km/s) pulsar candidate with a cometary pulsar wind nebula (PWN) located ~2 north-east from Sgr A*, just outside the radio shell of the supernova remnant Sagittarius A (Sgr A) East. Its non-thermal X-ray spectrum, measured up to 30 keV, is well characterized by a Gamma~1.6 power-law, typical of a PWN, and has an X-ray luminosity of L(3-30 keV)=1.3e34 erg/s. The spectral and spatial results derived from X-ray and radio data strongly suggest a runaway neutron star born in the Sgr A East supernova event. We do not find any pulsed signal from the Cannonball. The NuSTAR observations allow us to deduce the PWN magnetic field and show that it is consistent with the lower limit obtained from radio observations.
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