Radiative corrections to the semileptonic Dalitz plot with angular correlation between polarized decaying and emitted hyperons

Abstract

We obtain an expression for the Dalitz plot of semileptonic decays of polarized hyperons including radiative corrections to order ␣ and neglecting terms of the order ␣q/M 1 , where q is the four-momentum transfer and M 1 is the mass of the decaying hyperon. Our results are specialized to exhibit the angular correlation between such polarization and the momentum of the emitted hyperon. The model dependence of radiative corrections is kept in a general form within this approximation which is suitable for model-independent experimental analysis. Our final result, valid for charged as well as for neutral hyperons, allows us to obtain the angular spinasymmetry coefficient of the emitted hyperon. ͓S0556-2821͑97͒04709-7͔

Radiative corrections to the semileptonic Dalitz plot with an angular correlation between polarized decaying and emitted hyperons: Effects of the four-body region

“…[1], without repeating details that can be found there, and we shall introduce our notation. Second, it turns out that in order to study the FBR, it is convenient to follow the steps of Ref.…”

“…It is the purpose of this work to extend the calculations of Ref. [1] in order to incorporate the four-body contribution to the RC of the corresponding DP, in the same way as we did in Ref. [2].…”

“…Hereŝ 1 is the spin of A andp is a unit vector along the direction of the threemomentum of either the emitted baryonp 2 or the emitted charged leptonl. In the former case we can obtain the spin-asymmetry coefficient of the outgoing baryon [1], while in the latter we can obtain the spin-asymmetry coefficient of the charged lepton [2].…”

“…Accordingly, in Sec. II we summarize the main results concerning the RC to the Dalitz plot in the TBR [1], and we rearrange them in parallel to Ref. [2].…”

“…In previous works [1,2] we have obtained the radiative corrections (RC) to the Dalitz plot (DP) of hyperon semileptonic decays (HSD), A → Bℓν ℓ , for the case of polarized decaying hyperons (A and B are hyperons and ℓ and ν ℓ are the accompanying charged lepton and neutrino). In these calculations we have kept theŝ 1 ·p spin correlation displayed explicitly in the DP.…”