Question

A measurable form of this quantity is given by the convolution of parton (“PAR-tawn”) distribution functions with the “hard” form of it. This quantity is given by the following: “one over the flux factor,” times the integral over Lorentz-invariant (10[1])phase space of “some delta functions times the squared magnitude of the amplitude, denoted capital M.” In partial wave analysis, this quantity is: (10[1])“four pi over k squared,” times the sum (10[1])over L of the expression: “2L plus one,” all times “sine-squared of the Lth phase shift.” This quantity equals “four pi over the (-5[1])wave number,” all times (10[1])the “imaginary part (10[1])of the scattering amplitude evaluated at 0” (10[3])by the optical theorem. (10[1])This quantity equals the integral over the solid angle of its (10[1])differential, (10[1])which is a function of the impact parameter and scattering angle. For 10 points, (10[2])name this quantity that is the area (10[1])of the target (10[2])as (10[1])seen by the incoming particle (10[1])in a scattering process. (10[1])■END■ (10[2]0[2])

ANSWER: cross section [accept total cross section or integrated cross section or scattering cross section; accept partonic cross section, parton-parton cross section, parton collision cross section, or hard-scattering cross section; accept Lorentz-invariant cross section; after “differential” is read, accept differential cross section; until “differential” is read, reject “differential cross section”; reject any other more specific forms of cross section]
<Physics>
= Average correct buzz position

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Summary

2023 ACF Nationals04/22/2023Y2295%0%5%118.52

Buzzes

PlayerTeamOpponentBuzz PositionValue
Alex AkridgeIndiana AYale B3710
JD KrothIowa State AUC Berkeley A6010
Kevin YeUC Berkeley BTexas A6810
Vivek SasseChicago BCornell A91-5
Arya KarthikGeorgia Tech AChicago C9510
Adam FineChicago AVanderbilt A9810
Jason HongBrown AGeorgia Tech B10510
Richard NiuCornell BNorthwestern A10510
Steven LiuMIT APenn State A10510
Geoffrey WuColumbia AYale A10910
Vincent DuNorth Carolina AVirginia A12010
Noah ChenColumbia BToronto A12110
June YinWUSTL BOhio State A13510
Shardul RaoMinnesota ARutgers A13510
Paul LeeWUSTL APurdue A14210
Danny HanPenn AMaryland A14510
Mazin OmerHarvard AHouston A14510
Max ChemtovMcGill ARutgers B14610
Natan HoltzmanStanford ANYU A15110
Geoffrey ChenCornell AChicago B15510
Simon GorbatyDuke AIllinois A15610
Todd MaslykMichigan AFlorida B15610
Benjamin WeinerMinnesota BClaremont A1560
Tomás Aguilar-FragaClaremont AMinnesota B1560