We performed angle-resolved photoemission experiments on overdoped single crystal Bi2Sr2CaCu2O8+x samples with Tc values as low as 55K and very narrow transitions as measured by AC susceptibility. The photoemission data indicate the presence of a "shadow" peak in the quasiparticle spectral function A (ω) shifted by (π, π) from the conventional quasiparticle peak. The ratio of the shadow/quasiparticle peak amplitudes strongly increases with the binding energy. This is consistent with the idea that the shadow peak is not a structural replica of the quasiparticle peak, but rather a maximum in a spectral function which can exist due to interaction with spin fluctuations peaked at (π, π).
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AcknowZedge~~ts-We benefittedfr om ~nversations with Ph. Aebi, I. Bozovic, E. Dagotto, G. Grabovski, R. Joynt, A. Kampf, I. Mazin, A.Millis and R. Schri-effer.F inancials upportw asp rovidedb y the U.S. NSF, both directly and through support of the Wisconsin SynchrotronR adiation Center, Ecole Polytechnique FederaleL ausannea, nd the Fonds National Suissed e la RechercheS cientifiqueS. LR is an EC Fellow, C.K. is a National ResearchC ouncil Fellow,a nd AC. is an AX Sloan Fellow.