اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدتحليل اولي لقوة الإشعاع للبلورات المحصولة من التنغستات الخام عند درجات حرارة منخفضة
First study of radiation hardness of lead tungstate crystals at low temperatures
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المحول الالكترومغناطيسي لباندا في مرفق فيئر سيعتمد على عملية بلورات السنتيلاسيون الخاصة بالتنغستين الرصاصي (PWO) عند درجات حرارة قريبة من -25 مئوية عشرة لتوفير دقة كافية للأشعة في نطاق الطاقة من 8 جيجا فولت إلى 10 ميكرو فولت. تم دراسة صلابة الإشعاع لبلورات PWO في مرفق إشعاع الإشعاع في إيهيب (بروتفينو) في نطاق الحرارة من درجة حرارة الغرفة إلى -25 مئوية عشرة. وأظهرت هذه الدراسات فرقاً كبيراً في تطور العمليات التلفية في درجات حرارة أقل من درجة حرارة الغرفة. وأظهرت النتائج المختلفة في مستوى فقدان الإشارة في نفس معدل الجرعة ولكن عند درجات حرارة مختلفة. وأظهرت النتائج تأثير تخفيض كبير في عملية استعادة البلور في درجات حرارة أقل من 0 مئوية عشرة.
The electromagnetic calorimeter of PANDA at the FAIR facility will rely on an operation of lead tungstate (PWO) scintillation crystals at temperatures near -25 deg.C to provide sufficient resolution for photons in the energy range from 8 GeV down to 10 MeV. Radiation hardness of PWO crystals was studied at the IHEP (Protvino) irradiation facility in the temperature range from room temperature down to -25 deg.C. These studies have indicated a significantly different behaviour in the time evolution of the damaging processes well below room temperature. Different signal loss levels at the same dose rate, but at different temperatures were observed. The effect of a deep suppression of the crystal recovery process at temperatures below 0 deg.C has been seen.
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