We have measured in a single experimental setup, the differential cross sections and decay angular distributions of the Y ∗ (1385) produced in the two line-reversed reactions: π + p → K + Y ∗+ (1385) (279 events/ω b ) and K − p → π − Y ∗+ (1385) (190 events/ωb) at 11.5 GeV/ c . The data have been derived from a triggered bubble-chamber experiment using the SLAC Hybrid Facility. We find the differential cross sections and Y ∗ polarizations for the two reactions to be in agreement with exchange-degeneracy predictions, if kinematic differences are taken into account. The Stodolsky-Sakurai and additive quark model predictions are in agreement with the main features of the decay angular distributions of the Y ∗ (1385), except for small violations at low momentum transfer, which can be associated with a finite helicity non-flip contribution in the forward direction.
Axis error includes +- 10/10 contribution.
THESE FINAL DIFFERENTIAL CROSS SECTIONS ARE INCLUDED IN THE RECORD OF J. BALLAM ET AL., PRL 41, 676 (1978).
TRANSVERSITY AMPLITUDES FOR SIG(1385P13)+ PRODUCTION. THE IMAGINARY PARTS OF T(11) AND T(-1-1) WERE ARBITRARILY FIXED AT ZERO.
The amplitude and phase for coherent regeneration in hydrogen and deuterium have been measured for six momentum bins in the range 3.5-10.5 GeV/c. Over this region the phase, ϕf, is consistent with being constant and has the value - 60°±8° for hydrogen and - 46°±8° for deuterium. Power-law fits of the form plabn for the amplitudes when combined with other data give n=−0.60±0.02 for hydrogen and n=−0.52±0.02 for deuterium.
No description provided.
NOTE PHASE IS HERE DEFINED AS THE PHASE OF I*AMP(NAME=REGEN) AND SO DIFFERS BY 90 DEG FROM USUAL DEFINITION.