39K ve 41K İzotoplarının 0-20 MeV Enerji Aralığında Nötron Reaksiyonları Tesir Kesiti Hesaplamaları

Yıl 2017, Cilt: 22 Sayı: 1, 33 - 40, 29.06.2017

Nergiz Yıldız Yorgun , Ömer Faruk Özdemir

Öz

Force Free Helical Reactor (FFHR)
tasarımı, sıvı blanket sistemine sahip füzyon reaktörlerinden biridir. Flinak (LiF-NaF-KF),
FFHR‘de trityum üretimi, soğutucu ve ısı transferi için blanket olarak kullanma
potansiyeline sahip eriyik tuzlardan biridir.  Yüksek sıcaklıklarda düşük buhar basıncına
(900 ^°C
de 0,5 mmHg) sahip olan Flinak’ın korozyon karakteristikleri Flibe (Li₂BeF₄)
‘ye benzerdir ve termal iletkenliği



















 dir. FFHR tasarımlarında kullanım potansiyeli,
Flinak bileşenlerinin nükleer özelliklerinin belirlenmesinin önemini artırır.

Bu çalışmada ³⁹K ve ⁴¹K'in
0-20 MeV gelme enerjili nötronlarla gerçekleştireceği nükleer reaksiyonlardan
(n,p) ve (n,α) reaksiyonları için tesir kesiti hesaplamaları denge ve denge
öncesi modeller kullanılarak yapıldı. Hesaplamalarda denge öncesi için Full
Exciton Model, Hibrid Model, Geometri Bağımlı Hibrid Model ve Kaskad Eksiton
Model kullanılırken, denge modeli hesaplamalarında Weisskopf-Ewing Modeli
kullanıldı ve yapılan hesaplama sonuçları EXFOR, JEFF 3.2 ve TENDL-2015'den
alınan deneysel ve değerlendirilmiş tesir kesiti verileriyle karşılaştırıldı.

Anahtar Kelimeler

Tesir kesiti, Flinak, denge reaksiyonları, Denge öncesi reaksiyonlar

Calculation of Neutron Reaction Cross Sections of 39K and 41K Isotopes Between 0-20 MeV Energy Region

Öz

Design of Force Free Helical Reactor (FFHR) is one of the fusion reactor which has liquid

blanket system. Flinak is one of the molten salt to use thermal transfer, coolant and production of tritium

at FFHR. Corrosion characteristic of Flinak show similar properties to Flibe. Also, Flinak has low vapor

pressure at high temperature (at 900 C, 0.5 mmHg) and its thermal conductivity is k  0.92W / mK .

It is very important to determine nuclear potential of Flinak components due to potential use in FFHR

design.

In this study, we calculated (n,p) and (n,α) reactions cross section calculations for 39K and 41K with

neutron which has energy between 0-20 MeV using pre-equilibrium and equilibrium models. While FEM,

Hybrid, Geometry Dependent Hybrid Model and Cascade Exciton Model were used for pre-equilibrium

state, Weisskopf Ewing Model was used for equilibrium model calculations. Obtained results were

compared with experimental and evaluated cross section data obtained from EXFOR, JEFF 3.2 and

TENDL-2015.

Anahtar Kelimeler

Cross section, Equilibrium reactions, Flinak, Pre-equilibrium reactions

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