ZhETF, Vol. 136,
p. 1121 (December 2009)
(English translation - JETP,
Vol. 109, No. 6,
available online at www.springer.com
STRONG SUPPRESSION OF COULOMB CORRECTIONS TO THE e+e- PAIR PRODUCTION CROSS SECTION IN ULTRARELATIVISTIC NUCLEAR COLLISIONS
Lee R.N., Milstein A.I.
Received: August 6, 2009
PACS: 25.75.Dw, 12.20.-m, 25.20.Lj, 34.90.+q
The Coulomb corrections to the e+e- pair production cross section in ultrarelativistic nuclear collisions are calculated in the next-to-leading approximation with respect to the parameter , where γA,B are the Lorentz factors of colliding nuclei. We find considerable reduction of the Coulomb corrections even for large γAγB due to the suppression of the e+e- pair production with the total energy of the order of a few electron masses in the rest frame of one of the nuclei. Our result explains why the deviation from the Born result was not observed in the SPS experiment [Vane1994,Vane1997].