مطالعه زنجیره ایزوتوپی Ru100-106با استفاده از مدل سه ترازی بوزون برهم کنشی

نوع مقاله: مقاله پژوهشی کامل

نویسندگان

1 دانشگاه تبریز

2 هیأت علمی گروه فیزیک هسته ای دانشگاه تبریز

چکیده

در این مقاله طیف انرژی و سطوح انرژی هسته های واقع در ناحیه گذار فازی بین شکل های کروی و تغییر شکل یافته محوری بررسی شده است. برای توصیف همزمان حالات با اسپین پاریته زوج و فرد در قالب مدل بوزون برهمکنشی سه ترازی spd، هامیلتونین گذار فازی تعریف شده بر پایه جبر آفین(1،1)SU را استفاده نمودیم. با استفاده از نظریه کاتاستروف و فرمالیسم حالات همدوس، سطوح انرژی برای زنجیره ایزوتوپیRu100-106در ناحیه گذار فازی شکلی بین حدود (9)SO - (5)U مدل بوزون برهمکنشی تعیین گردید. پیش بینی های مدل، اطلاعات تجربی موجود برای این هسته ها را به خوبی بازیابی می نماید. همچنین تغییرات مشاهده شده در سطوح انرژی این هسته ها وجود یک گذار فازی شکلی مرتبه دوم را نشان می دهد. مقادیر حاصل برای پارامترهای کنترلی و همچنین شکل سطوح انرژی، هسته Ru100 را به عنوان نمونه مناسب نقطه بحرانی این گذار فازی شکلی معرفی می نماید.

کلیدواژه‌ها


عنوان مقاله [English]

Study of 100-106Ru isotopic chain in the three levels interacting boson model

نویسنده [English]

  • Hadi Sabri 2
2 Faculty of physics, University of Tabriz, Tabriz,Iran.
چکیده [English]

In this paper, we have considered the energy levels and energy surfaces of nuclei located between the spherical and the gamma soft shapes. We have used a three levels spd-interacting boson model which are defined in the affine SU(1,1) algebra to describe both positive and negative parity states. The energy surfaces of 100-106Ru isotopes are determined via catastrophe theory and coherent states formalism in the U(5)-SO(9) transitional region of interacting boson model. The agreement between the theoretical prediction of model and the most recent experimental counterparts is acceptable. Also, the variation of the energy surface’s shapes suggest a second order shape phase transition in this isotopic chain. The values of the control parameters and also the shape of energy surfaces suggest 100Ru as the best candidate for the critical point of this transitional region.

کلیدواژه‌ها [English]

  • Quantum shape phase transition
  • coherent state
  • three levels Interacting Boson Model (IBM)
  • energy surfaces

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