sPHENIX bulk physics topical group

[Ron Belmont <belmonrj AT gmail.com>]

Hi All,

Following on the discussion at the general meeting, I’d like us to consider the following questions for some of the early Year-1 ("Day-1") analyses we’re interested in doing.

a) What detector subsystems are needed?

b) What are the expected dominant systematic uncertainties, and how will they be determined?
c) Which calibrations are needed (including centrality, event plane)?
d) What are the MC needs beyond that which is currently available?
e) What is the minimum luminosity necessary for the measurement to succeed?

You can reply to the list (encouraged) or to me privately, whichever you prefer.

*** To help out with an example, for Day-1 I’m interested in cumulant v2{2,4,6,8,10}.  Here are my answers: ***

a) For the final analysis, full tracking is needed, but as an intermediate step this analysis could possibly be done with tracklets, single layer hits, etc.

b) Typically the uniformity of the azimuthal acceptance, though sometimes the detector alignment.  Either can be checked with looking at the average Q-vector values as a function of centralty/multiplicity and z-vertex.

c) Centrality would be nice, but not required.  No event plane needed.  Properly calibrated tracks would necessary for a final result, but not for an early result with tracklets or hits.

d) No MC needs.

e) For just the v2{2,4,6,8} about 1 billion events is sufficient.  For accurate ratios like v2{6}/v2{4} and and v2{8}/v2{6} probably more like 20 billion.  No good answer for the v2{10}, we’ll just have to find out.

Cheers,

Ron

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Ron Belmont (he/him/his)
Past Chair, RHIC/AGS Users' Executive Committee
Assistant Professor, Department of Physics & Astronomy
University of North Carolina at Greensboro
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Ron Belmont (he/him/his)
Past Chair, RHIC/AGS Users' Executive Committee
Assistant Professor, Department of Physics & Astronomy
University of North Carolina at Greensboro
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