does not challenge any conclusion drawn in the interpretation of our data [2] but even strengthens some of them. The Comment suggests that the effective Lagrangian analysis (ELA) [3] is better suited for a detailed interpretation of our precision data. Our analysis makes use of the fact that (1) the total cross section is dominated strongly by the excitation of the Stt(1535) resonance and (2) that its shape can be parametrized by a Breit-Wigner type resonance curve with an energy dependent width. The ELA includes nucleon Born terms and vector meson exchange in addition to the excitation of resonances. Both analyses, however, give the same results for the S&t resonance simply because (1) and (2) are valid. This statement, which in our Letter is based on the energy dependence of the total cross section and the shape of the angular distributions, is strongly supported by the results presented in the Comment. In their Table I, the authors compare the helicity amplitude At/~o btained from our data with their ELA (column 1) to those from Breit-Wigner fitting used by us (column 4). Both analyses give almost identical results; certainly there is no significant discrepancy within errors. The large differences between the rows of the table are due to the values used for the total width I R and, in particular, for the partial width I "ofthe St t resonance. As already pointed out in our Letter, these hadronic widths now dominate the uncertainty of At/2. More explicitly, our Eq. (6) [2], together with the resonance position WR = 15441 3 MeV and a corresponding cross section of tT(WR) = 16~0.8 p, b, gives the following expression for At/2. . I MVb'/ At/p[10 GeV '/ ] = (5.82~0.15) b") with b"= I "/b". All entries in Table I of the Comment can be reproduced with this expression [the authors do not quote I"~a nd b" for row (c) of their table; however, a comparison of At/2 and g yields I It/b"= 290 MeV]. The parameter $ introduced by the Comment via [2] (I + jq+ ) t/2(m /W )1/2(b /I ) t/2g 1/2 (2) obviously avoids the uncertainty in I R/b"at the expense of mixing electromagnetic and strong coupling. Assuming again the dominance of the S~~resonance, it may be calculated from our Breit-Wigner analysis via C =~2 7r l~o+(Wtt) I = I "[t7(W~)]'/' (3) 2~q*"Using the values for W~and o (Wtt) given above leads to g = (2.21~0.06) X 10 4 MeV ', which is in excellent agreement (better than 1%) with the most complete ELA fit (row c of Table I). In our Letter we had assumed a very conservative upper limit of 10% for non-5]~contributions to the total cross section, giving rise to a 5% uncertainty of~Eo+(Wlt)~. However, the agreement on the 1% level demonstrated here suggests that non-S]~contributions to this number are really negligible. We thus agree that the value of the parameter s is model independent; due to the dominance of the S&& resonance, it is entirely fixed by the measured cross section.We thank the authors of the Comment for pointing out the overall sign error of the cos(O'") term in Eq. (7) [1], which, however, has no consequence ...
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