Forward upgrade -- Jet Projection for BUR -- 2021-05-12


Assumes anti-kT with R=0.6, pT>4 GeV/c, 350 pb^{1} and P=0.6


xF All Jets With z > 0.5 h+ With z > 0.5 h-
0.15 1.39E-04 3.43E-04 4.04E-04
0.25 6.52E-05 1.64E-04 2.11E-04
0.35 7.69E-05 2.10E-04 2.95E-04
0.45 1.31E-04 3.84E-04 5.90E-04
0.55 2.75E-04 7.95E-04 1.48E-03
0.65 7.12E-04 2.48E-03 4.75E-03

 Collins, all jet pt range:

Hadron z h+ in jets h- in jets
0.15 9.06E-05 9.73E-05
0.25 1.21E-04 1.34E-04
0.35 1.54E-04 1.79E-04
0.45 1.96E-04 2.38E-04
0.55 2.53E-04 3.19E-04
0.65 3.25E-04 4.29E-04
0.75 4.03E-04 5.43E-04
0.85 5.97E-04 8.68E-04

Colins, in different jet pt bins:

  4 < jet Pt < 5   5 < jet Pt < 7   7 < jet Pt < 9
Hadron Z h+ in jets h- in jets   h+ in jets h- in jets   h+ in jets h- in jets
0.15 1.61E-04 1.73E-04   1.56E-04 1.66E-04   1.84E-04 1.95E-04
0.25 2.06E-04 2.25E-04   2.04E-04 2.28E-04   2.54E-04 2.86E-04
0.35 2.61E-04 2.93E-04   2.64E-04 3.00E-04   3.21E-04 3.99E-04
0.45 3.26E-04 3.82E-04   3.35E-04 4.01E-04   4.18E-04 5.51E-04
0.55 4.01E-04 5.08E-04   4.31E-04 5.47E-04   5.62E-04 7.01E-04
0.65 5.11E-04 6.45E-04   5.51E-04 7.74E-04   7.48E-04 9.35E-04
0.75 6.45E-04 8.10E-04   6.86E-04 9.54E-04   8.81E-04 1.32E-03
0.85 9.54E-04 1.32E-03   9.67E-04 1.48E-03   1.40E-03 2.21E-03

Bottom line:  For the xF = 0.25 and 0.35 data points, we should be able to distinguish the leading h+ vs. leading h- curves from the right-hand panel of 2020 BUR Fig. 66 at the 10 sigma level.  For xF = 0.45, the sensitivity drops to “only” ~8 sigma.

A few “details”:

--   We have assumed 500 Hz will be available for Forward Upgrade jet triggers.

--   We have assumed two JPs per side, one spanning 2.5 < eta < 3.5 and one spanning 3 < eta < 4.  We have adopted the same pT thresholds for both (4, 6, 7.5 GeV/c), but with different prescales for low-eta vs. high-eta.

--   Lacking a true JP trigger simulator, we have just split the jets at eta = 3.25 for purposes of assigning prescales.

--   The uncertainties for 0.1 < xF < 0.2 will be considerably smaller than shown here.  The “50 GeV in a box” PYTHIA filter rejected a bunch of those events.

--   The previous note implies we have also underestimated the required bandwidth.  The “excess yield” will fall almost entirely into the 2.5 < eta < 3.5, 4< pT < 6 GeV/c bin.  That bin only contributes 25% of the total statistics for the 0.2 < xF < 0.3 bin, and an even smaller fraction for the higher xF bins.  So we can afford to increase its prescale if need be.

And of course, all of these assumptions will be need to be optimized when the full JP trigger simulator becomes available.