N*Production inπ±−pand

K. J. Foley

¹

,

R. S. Jones

²

,

S. J. Lindenbaum

³

et al.

Pion-Nucleon Interactions

“…Figure 10 shows that at a pion laboratory momentum of 2.0 GeV / c the 'YJ-P cross section has fallen through more than 2 decades at cos () = 0.5 ; at 8 GeV / c it falls 6 decades in the same angular interval. Foley et al (84) have investi gated the extreme forward direction so as to observe the interference with Coulomb scattering and thus measure the ratios cy± = Rej±(O)/Im f±(0) where (Equation from Coulomb interference is found (84) as illustrated in Figure 11. The re sult verifies the 7rp forward dispersion relations up to 20 GeV and this may be expressed by remarking (84,88) that if there exists a small acausal region or fundamental length .e, the forward dispersion relations would break down at an energy corresponding to 1/.e.…”

Consequences ofSU(3)′′Excitation in Baryon Resonances

“…[22][23][24][25][26][27][28] The differential cross section for these processes can be represented for small t in the form d<r/dt=Ae bt .…”

Single-Isobar Production in Proton-Proton Interactions at 28.5 GeV/c

“…In the lowt region the />7r + 7r~" effective mass peaks in the low-mass end of the spectrum at -1450 MeV. Comparing this with mr + at low t we see that the mr + spectrum is centered at 1400, is much broader, and has a greater cross section in spite of the loss of events with very low t [see item (2) above]. At large t, the />7r + 7r~" spectrum shows no peak at around 1450, but structure at higher masses including the 1600-to 1700-MeV region becomes more prominent.…”

“…1 Figure 2(a) shows MMX from all twoand four-prong events for />0.06 (GeV/c) 2 along with a solid curve that shows the counter results on the same scale as our data, integrated over the same t region. The cut on t is chosen to include a region in which scanning losses are slight [see item (2) above]. The shaded histogram in Fig.…”