LETTERE AL NUOVO CIMENTO VOL. 17, N. 15 11 Dieembre 1976 Masses of Charmed Baryons ('). G. JAKIMOW Ddpartement de Physique Universitd Du Quebec ~ Montrdal, C.P. 8888, Montrdal, Que., Canada C. S. KALMAN (**) Physics Department Indiana University . Bloomington, Ind. 47401. (ricevur il 29 Settembre 1976) In a previous paper (1) we obtained a one-parameter mass formula for charmed baryons. Now that the charmed analogue of A(lllS) with a mass of 2250 MeV has been observed (2), this parameter can be evaluated and the masses of the rest of the charmed baryons predicted. As in the previous paper baryons are named according to their isospin I and strangeness minus charm S -- C. The symbol X is used to describe an I = 1 particle with S--C =- 1. A subscript is used to denote the charm if it is not zero. Although the general formula given in equation (18) of the previous paper is correct, the explicit results noted for the sextet were in error. The correct results for all charmed baryons are as follows: Sextet (U = 1) M(E+) = 936.3--262.8D, M(E+) = 1128.6-- 262.8D, M(g2+) : 1312.5-- 262.8D. Antitriplet (C= + 1) M(~+) ~ 1181.2--157.7D, M(A+) = 944.6-- 157.7D, (*) "Work supported in part by the National Research Council (Canada) and in part by the U.S. Energy Research an4 Development Administration. Concordia University 411 Quebec, Elementary Particle Physics Group, CUQ/EPR-76/11. (**) Permanent address: Loyola Campus, Co~cordia University, Montreal, Canada tttB 1R6. (1) G. 5A~IMOW and C. S. KAL.~IAN: Lelt. N~tovo Cirnento, 17, 511 (1976). (~) B. ~V. LEE, C. QuIoG and J. L. ROSNER: FERMILAB-PUB-76171-THY (August 1976). 516

Masses of charmed baryons

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LETTERE AL NUOVO CIMENTO VOL. 17, N. 15 11 D i e e m b r e 1976

Masses of Charmed Baryons ( ' ) .

G . J A K I M O W

Ddpartement de Physique Universitd Du Quebec ~ Montrdal, C.P. 8888, Montrdal, Que., Canada

C. S. KALMAN (**)

Physics Department Indiana University . Bloomington, Ind. 47401.

(ricevur il 29 S e t t e m b r e 1976)

In a p r ev ious p a p e r (1) we o b t a i n e d a o n e - p a r a m e t e r mass f o r m u l a for c h a r m e d ba ryons . Now t h a t t h e c h a r m e d ana logue of A ( l l l S ) w i t h a mass of 2250 MeV h a s been obse rved (2), t h i s p a r a m e t e r can be e v a l u a t e d a n d t h e masses of t h e r e s t of t h e c h a r m e d b a r y o n s p red ic t ed . As in t h e p r e v i o u s p a p e r b a r y o n s are n a m e d accord ing to t he i r i sospin I a n d s t r angenes s m i n u s c h a r m S - - C. The s y m b o l X is used to descr ibe an I = 1 pa r t i c l e w i t h S - - C = - 1. A s u b s c r i p t is used to d e n o t e t h e c h a r m if i t is n o t zero.

A l t h o u g h t h e genera l f o r m u l a g iven in e q u a t i o n (18) of t h e p r ev ious p a p e r is correct , t h e expl ic i t r e su l t s n o t e d for t he s ex t e t were in error . The cor rec t r e su l t s for all c h a r m e d b a r y o n s are as fol lows:

S e x t e t (U = 1)

M(E+) = 9 3 6 . 3 - - 2 6 2 . 8 D ,

M(E+) = 1 1 2 8 . 6 - - 2 6 2 . 8 D ,

M(g2+) : 1 3 1 2 . 5 - - 2 6 2 . 8 D .

A n t i t r i p l e t ( C = + 1)

M(~+) ~ 1 1 8 1 . 2 - - 1 5 7 . 7 D ,

M(A+) = 9 4 4 . 6 - - 157 .7D,

(*) "Work s u p p o r t e d in p a r t b y the N a t i o n a l R e s e a r c h Counci l (Canada) a n d in p a r t b y t h e U.S . E n e r g y R e s e a r c h a n 4 D e v e l o p m e n t A d m i n i s t r a t i o n . C o n c o r d i a U n i v e r s i t y 411 Quebec , E l e m e n t a r y P a r t i c l e P h y s i c s Group , C U Q / E P R - 7 6 / 1 1 . (**) P e r m a n e n t a d d r e s s : L o y o l a C a m p u s , Co~co rd i a U n i v e r s i t y , M o n t r e a l , C a n a d a t t t B 1R6 . (1) G. 5A~IMOW a n d C. S. KAL.~IAN: Lelt . N~tovo Cirnento, 17, 511 (1976). (~) B. ~V. LEE, C. QuIoG a n d J . L. ROSNER: F E R M I L A B - P U B - 7 6 1 7 1 - T H Y (Augus t 1976).

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