176,178,180Hf İZOTOPLARINDA FOTON SAÇILMA TESİR KESİTLERİNİN HESAPLANMASI

Öz

Spini ve paritesi Iπ =1+ olan çekirdek seviyelerinin gözlenmesinde foton saçılma tesir kesitlerinin önemli yeri vardır. Bu seviyeleri karakterize eden Γγ radyasyon kalınlıkları ve B(M1) değerleri deneylerde gözlenen tesir kesitlerinden hesaplanmaktadır. Bu çalışmada makas mod uyarılmalarının esnek olamayan γ-çekirdek saçılma tesir kesitleri 176,178,180Hf izotopları için, teorik olarak dönme değişmez Kuazi-parçacık Rastgele Faz Yaklaşımı (QRPA) kullanılarak araştırılmıştır. Bu seviyelerin (K=1) foton saçılma reaksiyonlarında gözlenen σγγ›, B(M1) ve Γγ radyasyon kalınlıkları teorik sonuçlarla karşılaştırılarak incelenmiştir. Genel olarak teorik ve deney sonuçlarının, ölçüm hataları çerçevesinde, uyum içinde olduğu görülmüştür. Hesaplamalar Hf izotoplarında manyetik dipol 1+1 seviyelerin, iyi deforme çekirdeklere nazaran daha az ayrışmakta olduğunu göstermiştir. Teori düşük enerjilerde birkaç tane E1-elektrik dipol uyarılmalarının varlığını da öngörmektedir. Teorik ve deney sonuçlarının karşılaştırılması gözlenen seviyelerin paritelerinin belirlenmesinde deneycilere ipucu sağlayacaktır.

Anahtar Kelimeler

• 176
• 178
• 180Hf
• Saçılma Tesir Kesiti
• QRPA
• Manyetik Dipol

176,178,180Hf İZOTOPLARINDA FOTON SAÇILMA TESİR KESİTLERİNİN HESAPLANMASI

Öz

In the observation of Iπ = 1+ levels ın nuclei photon scattering cross sections have an important place. Γγ radiation thickness and B (M1) values which characterize this level are calculated from the cross sections observed in the experiments. In this study non flexible γ-nuclei scattering cross sections of the scissors mode excitations for 176,178,180Hf isotopes were theoretically investigated using the rotation invariant Quasiparticle Random Phase Approximation (QRPA). σγγ’, B(M1) ve Γγ radiation thickness observed in the photon scattering reaction of these levels (K=1) is compared with the theoretical results. In general, the theoretical and experimental results in accordance with the measurement error, is seen to be ingood agrement. The calculations of the magnetic dipole 1+1 levels in Hf isotopes showed that the decompsitation in this isotope chain is less that observed in well deformed nuclei decomposed. Theory predicted the presence of a few E1-electric dipole excitations at low energies. The comparison of the theoretical and the experimental results will provide clues to the experimenters in the determination of the parity of the observed levels

Anahtar Kelimeler

• 176
• 178
• 180Hf
• scattering cross section
• QRPA
• magnetic dipol

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