SLAC-PUB-1706 - SLAC - Stanford University

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production -8- e+e-- -PSI-l-Y l The peak at -0.3 GeV2 is from the decay $‘-q$ * (3c) After subtracting 2n0 contribution, the radiative contribution, and cutting out the region of the -q , we find l)’ -YP c PC++ Zc, 4 all ’ P --L all c =3.6f0.7% . Since the Hofstadter group limit on single y-rays in this energy region is 5%, this state must decay principally to y$. We have also observed states with masses between those of the $’ and the $ by observing the hadronic decay modes of these intermediate states as follows: 1 X- r +-+- 7r7rlT7r 1 -i- -+-+- 7r717T7rTr7f T+ ,-K+K- 1 1;‘~~ and/or K’K- The one-constraint fitted mass distributions of the hadronic systems of reaction (6) are shown in Fig. 13. The shaded regions show those events consistent with the direct decay of the +’ into charged particles with no y-ray (4-constraint fits). The 4-pion mass distribution of Fig. 13a shows two distinct peaks, one at 3.41 GeV with the FWHM of -20 MeV, consistent with our resolution, and the other at 3.53 GeV, with the FWHM of -60 MeV, which is considerably broader than our resolution. The peaks in the 6-pion and nnKK mass distributions tend to confirm the 4-pion results. There are insufficient data in these channels to prove inde- pendently the existence of two states. The 71~ or KK distribution of Fig. 13d shows only one peak at a mass of 3.41 GeV corresponding to the lower of the two peaks in the 4-pion distribution. Be- cause of this decay mode, this state must have natural spin-parity as . well as even charge conjugation, i. e. , J PC&-+ , 2*, . . . Table III gives our measure- ments of the production branching fractions of the intermediate states for decay by a particular mode. Each of these branching fractions is the product of the (4) (6)
-9- Table III Branching fractions in % for various decay modes of the intermediate states x and PC. Decay mode x(3410) x(35 30) pC 47r* 0.14 * 0.07 0.2i: 0.1 ? 67r” -0.1 -0.2 ? 7;rn-K+K- -0.07 -0.05 ? T+T- or K+K- 0.13 le 0.05 < 0.027
Page 1 and 2: THE TOTAL HADRON CROSS SECTION, NEW
Page 3 and 4: -3- to zero. Any particle coupled t
Page 5 and 6: -5 - We have taken further data in
Page 7: -7- an e+e- pair is detected coming
Page 11 and 12: - 11 - The sample is further reduce
Page 13 and 14: .- - 13 - We can examine various an
Page 15 and 16: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
Page 17 and 18: MUON SPARK CHAMBERS FLUX RETURN \ C
Page 19 and 20: 2.5 2.0 1.5 1.0 0.5 0 -22 0 2 0.0
Page 21 and 22: 40 30 5; z 20 b’ IO 0 . . t tn~~
Page 23 and 24: 6 d 0 I I I I I I I I I J 0 3.2 3.4
Page 25 and 26: 100 - 1 O- 25 . 30 35 i (p+p-) (GeC
Page 27 and 28: 32 . 3.1 l 8 0 0 \cI ‘-+rr t e+e-
Page 29 and 30: 20 I5 IO 5 0 5 0 IO 5 0 5 - - - I i
Page 31 and 32: 30 1 I I 1 1 20 0 i -O- 3 5 6 7 TOT
Page 33 and 34: 0 IO 5 P E O 3 20 15 IO 5 0 I] . .

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