A conversation with Michael D. Jackson, writer and reader: on being an outsider, and the aporias of lived experience

A discussion on vacuum polarization correction to the cross-section of e + e − → γ * / ψ → μ + μ −

“…The radiative correction of process e + e − →µ + µ − includes the initial-state and final-state corrections. The finalstate radiative (FSR) correction is much smaller than the initial-state radiative (ISR) correction owing to the mass relation, m e ≪m µ [6]. The FSR correction can be neglected if one dose not require very high accuracy.…”

Electroweak interaction

“…The method for reconstructing secondary vertices is to search for space points in 3D where track density functions overlap [84]. Each track is parameterized by a Gaussian probability density tube f ( r) with a width equal to the uncertainty in the track position at its point of closest approach (POCA) to the IP, r 0 ,…”

“…In addition, the radius of the first CDC hit is required to be < 39.0 cm, 2-D impact parameter in xy <1 cm, at least 2 VXD hits, and a distance of closest approach to the IP in z < 1.5 cm. The topological vertexing method described earlier [84] is used to find secondary vertices, and the P t -corrected mass is then required to be > 2 GeV/c 2 in the event hemisphere to tag Z → bb events. Note that there is no procedure to reject IP or light flavor tracks.…”