Measurement of isomeric yield ratios of ^{86<i>m</i>,<i>g</i>}Y and ^{87<i>m</i>,<i>g</i>}Y in the quasi-monoenergetic neutron induced reactions of ⁸⁹Y

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>The isomeric yield ratios (IR) of <SUP>86<I>m</I>,<I>g</I> </SUP>Y and <SUP>87<I>m</I>,<I>g</I> </SUP>Y were measured in the 23 to 37 MeV quasi-monoenergetic neutron induced reaction of <SUP>89</SUP>Y by using an off-line <I>γ</I>-ray spectrometric technique. The IR values in the <SUP>89</SUP>Y( n , x n ) reactions were also calculated using the TALYS 1.8 code and found to be in good agreement for <SUP>87<I>m</I>,<I>g</I> </SUP>Y but slightly less for <SUP>86<I>m</I>,<I>g</I> </SUP>Y. The IR values of <SUP>86<I>m</I>,<I>g</I> </SUP>Y and <SUP>87<I>m</I>,<I>g</I> </SUP>Y from the present work in the <SUP>89</SUP>Y( n , x n ) reactions were compared with the literature data in the <SUP>89</SUP>Y( γ , x n ), <SUP>89</SUP>Y( p , x ) and <SUP>89</SUP>Y( α , x ) reactions. It was found that the IR values of <SUP>86<I>m</I>,<I>g</I> </SUP>Y and <SUP>87<I>m</I>,<I>g</I> </SUP>Y in all these reactions increase with excitation energy. At the same excitation energy, the IR values are higher in the alpha induced reaction than in the proton, neutron and photon induced reactions due to higher input angular momentum in the former than in the later. These two observations indicate the role of entrance parameters. However, it is surprising to see that at the same excitation energy, the IR values of <SUP>86<I>m</I>,<I>g</I> </SUP>Y and <SUP>87<I>m</I>,<I>g</I> </SUP>Y in the <SUP>89</SUP>Y( n , x n ) reaction are nearly constant and significantly higher than in the <SUP>89</SUP>Y( γ , x n ) reaction.</P>