Note on units and nomenclature

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NOTE ON UNITS AND NOMENCLATURE 1. U s e of B r i t i s h u n i t s

I t h a s b e e n p o m ~ t o u t to t h e Edxtor t h a t t h e r e is no r e a s o n (except p e r h a p s in v e r y exceptaonal cases) to t o l e r a t e (as h a s h i t h e r t o b e e n done) t h e u s e of B r ! t l s h u m t s in t h e d e s c r x p t m n of a p p a r a t u s a n d e x p e r t m e n t a l a r r a n g e m e n t s . C o n t r i b u t o r s a r e a c c o r d i n g l y r e q u e s t e d to give all m e a s u r e m e n t s e x c l u s i v e l y In m e t r i c a l u m t s , m m a n u s c r i p t s d m r e g a r d m g t h i s r e q u e s t , t h e n e c e s s a r y c h a n g e s will be m a d e b y t h e editorial staff, In case of d o u b t , t h e m a n u s c r i p t will be r e t u r n e d to t h e a u t h o r s for e m e n d a t t o n

2. N o m e n c l a t u r e of n u c l e a r s p e c i e s F r o m occasional reactaons of colleagues t h e E d t t o r h a s g o t t h e l m p r e s m o n t h a t t h e r e m still w i d e s p r e a d c o n f u s i o n o n t i n s p o i n t . T i n s c o n f u s m n armes f r o m t h e f a c t t h a t , m o r d e r to d e s i g n a t e t h e n u c l e a r species c h a r a c t e r i z e d b y t h e d o u b l e d i c h o t o m y A even

Z even, N e v e n Z odd, N o d d

.4 o d d

Z even, N o d d Z odd, N even,

t w o s y s t e m s of n o m e n c l a t u r e a r e u s e d c o n c u r r e n t l y System 1 even nuclei o d d nuclex

System 2

even-even odd-odd {even-odd odd-even

even-.4 n u c l e i

{ even-even odd-odd

o d d - A nuclex

{ odd-N odd-Z.

T h e r e s h o u l d b e little h e s l t a t a o n m a d m i t t i n g t h a t S y s t e m 2 is far s u p e r i o r to SysLem 1, a n d tt ,s there/ore thts S y s t e m 2 which ~s adopted zn th~s 1ournal, w i t h m o d i f i c a t i o n s of p u r e f o r m w h i c h do n o t In t h e l e a s t a l t e r i t s s t r u c t u r e (a) T h e u s e of (undefIned) s y m b o l s A , N , Z m a n u n n e c e s s a r y c l u m s i n e s s , since t h e r e are p l a i n w o r d s fulfilling t h e s a m e f u u c t a o n o d d - m a s s nucleus, o d d - n e u t r o n n u c l e u s c o n v e y t h e s a m e idea as odd-.4, o d d - N n u c l e u s m a m o r e i m m e d i a t e w a y (b) T h e repeiatlon I n v o l v e d In e v e n - e v e n , o d d - o d d is o b v i o u s l y s u p e r f l u o u s , a n d to d r o p It c a n c a u s e n o c o n f u s i o n ( w i t h i n t h e f r a m e w o r k of S y s t e m 2). O n e t h u s a r r i v e s a t t h e n o m e n c l a t u r e c o n s i s t e n t l y u s e d in t h i s j o u r n a l even

even-mass nuclei

odd

odd-mass nuclei

odd-neutron odd-proton.

I t m u s t b e s t r e s s e d o n c e m o r e t h a t t h i s n o m e n c l a t u r e is not a n I n n o v a t i o n , b u t is essentmlly tdentscal v n t h t h e w i d e l y u s e d S y s t e m 2 People a c c u s t o m e d to t h e r e p e t i t i v e n a m e s e v e n - e v e n , o d d - o d d m a y , xf t h e y wish, r e g a r d t h e s i m p l e f o r m s even, o d d as a b b r e w a t l o n s , or r e a d t h e m t h r o u g h a piece of I c e l a n d s p a r : i t will n o t c h a n g e t h e i r m e a m n g N o a m b i g u i t y c a n arise f r o m t h e u s e of t h e s i m p l e f o r m odd, m t h e m e a m n g of o d d - o d d , ~/ there ts general agreement to use only S y s t e m 2 Since t h e e h m m a t m n of S y s t e m 1 w o u l d s e e m to be desirable also for o t h e r r e a s o n s (the a l t e r n a t a o n e v e n - o d d , o d d - e v e n is u t t e r l y c o n f u s i n g ) , it s h o u l d n o t b e too d l f f m u l t (one w o u l d hope) to r e a c h s u c h a n a g r e e m e n t

[ 10.E ]

ERRATUM

J. R. Bird, M. C. Moxon and F. W. K. Firk, Gamma ray spectra and parameters of neutron resonances in mercury (Nuclear Physics 13 (1959) 525). On p. 538, line 15 from bottom, instead of 'odd isotopes' read 'odd-mass isotopes'.