اندازه‌گیری نسبت بهره ایزومری 115m,gCd در واکنش (116Cd(γ, n با استفاده از فوتون‌های تابش ترمزی با بیشینه انرژی MeV 40-75

نوع مقاله: مقاله پژوهشی کامل

نویسنده

دانشکده فیزیک، پردیس علوم، دانشگاه یزد، یزد، ایران

چکیده

نسبت بهره ایزومری 115m,gCd با انجام واکنش در کادمیوم طبیعی با استفاده از فوتون‌های تابش ترمزی با بیشینه انرژی 40، 45، 50، 55، 60، 65، 70 وMeV 75 برای اولین بار اندازه‌گیری شده است. آزمایش‌ها با روش طیف‌سنجی غیر بر خط پرتو گاما با استفاده از شتابدهنده خطی الکترون MeV 100 در آزمایشگاه شتابدهنده شهرپوهانگ (PAL) در کشور کره جنوبی انجام گردید. هم‌چنین نسبت بهره ایزومری115m,gCd با استفاده از کد 1.6 TALYS محاسبه گردید. نتایج تجربی نسبت بهره ایزومری در واکنش‌ 116Cd(γ, n)115m,g Cd حاصل از این آزمایش و آزمایش‌های دیگران، با مقادیر تئوری حاصل از کد TALYS مقایسه شده و نتایج آزمایش توافق خوبی با نتایج حاصل از کد دارند. با افزایش انرژی بیشینه فوتون‌های تابش ترمزی، مقادیر تئوری و تجربی نسبت بهره ایزومری 115m,gCd افزایش می‌یابد که نشان‌دهنده اثر انرژی برانگیختگی است. هم‌چنین نسبت بهره ایزومری 115m,gCd از انرژی آستانه واکنش تا انرژی MeV ۱۸ به سرعت افزایش می‌یابد و در انرژی‌های بالاتر روند افزایشی کندی دارد. این رفتار نشان‌دهنده نقش تشدید بزرگ دوقطبی به همراه اثر انرژی برانگیختگی است.

کلیدواژه‌ها


عنوان مقاله [English]

Measurement of isomeric yield ratio of 115m,gCd in the 116Cd(γ,n) reaction at the end-point bremsstrahlung energies of 40-75 MeV

نویسنده [English]

  • Mansoureh Tatari
Department of Physics, Faculty of Science, Yazd University, Yazd, Iran
چکیده [English]

The Isomeric Yield Ratio (IYR) of 115m,gCd in the 40, 45, 50, 55, 60, 65, 70 and 75 MeV bremsstrahlung induced reaction of natCd has been determined for the first time by off-line gamma ray spectrometric technique using 100 MeV electron linac at Pohang Accelerator Laboratory (PAL), Pohang, Korea. The IYR of 115m,gCd as a function of bremsstrahlung energy was also calculated theoretically using computer code TALYS 1.6. The experimental IYR in the 116Cd(γ,n)115m,gCd reaction obtained in the present work along with literature data at lower energies are compared with the theoretical value from TALYS and found to be in general agreement. It was observed that the experimental and theoretical IYR of 115m,gCd increases with the increase of end-point bremsstrahlung energy, which shows the effect of excitation energy. It was also seen that the IYR of 115m,gCd increases sharply from the reaction threshold value to end-point bremsstrahlung energy of 18 MeV and thereafter increase slowly. This indicates the role of Giant Dipole Resonance (GDR) besides the effect of excitation energy.

کلیدواژه‌ها [English]

  • Isomeric Yield Ratio (IYR)
  • 116Cd(γ
  • n)115m
  • gCd photo-nuclear reaction
  • off-line γ-ray spectrometric technique
  • TALYS 1.6
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