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NCC Task Force

Richard SetoNCC Task Force Meeting

Dec 4, 2007BNL

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Agenda Reports

Its Dec 4–asses whether Dec 20 is a reasonable goal for completion. Report from

Dave/Stefan – pi0, dir photon Carla/Sky - chic Ken – delta G Edouard/Ondrej – general state of

reconstruction/calibrations The question is can we start the following:

Some folks will start to write: Goal? Doc to collaboration, mid -Jan

Doc to DOE – end of Jan, before QM I will have to give an update for the Wed

core week meeting so please provide me with plots by next Tues meeting

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Goals Started with ncc bullets The goals in simplest terms for the NCC task force is to

produce the following figure of merit (FOM) plots from realistic physics simulations. Realistic means a full simulation using PISA with detector response, reconstruction, and data analysis.

a) R_AA for pi0 as a function of pt for various centralities in AuAu and dAu collisions

b) Direct photons cross sections, and likewise R_AA. c) R_AA for the Chi_C via its decay to J/psi photon as a function

of pt for various centralities. Very likely we will limit this to rapidity 1-1.5

d) A_LL(pt) for direct photons in 500 GeV polarized pp collisions

d') Because we already have jet reconstruction going in pp collisions we should easily be able to use this information to get A_LL(x) giving a greater sensitivity to low-x

e) a demonstration that we can we can extract pi0's at various angles in various centrality collisions with a known efficiency - This should answer the projective Geometry question.

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ngammas, from edouards new code, a new chi2 from Ondrej

richard setoDec 4

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Ngammas

black- from MCred – from NCC edouards new code

black – mc ngammasred=ntracks

black – mc ngammasred=ngammas where I cut chi2<10

cut E>300 MeV cut E>1000 MeV

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Ngammas +Ondrej new chi2

black- from MCred – from NCC edouards new codeondrej’s new code

conclusionchi2<10 goodLow energy need recalibration

black – mc ngammasred=ntracks

black – mc ngammasred=ngammas where I cut chi2<10

cut E>300 MeV cut E>1000 MeV

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chi2=Lchi2+Tchi2 I think Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

from thisI think maybeI should cut atln(chi2)=4or chi2=50

instead of 10?

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chi2=Lchi2+Tchi2 I think Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

from thisI think maybeI should cut atln(chi2)=4or chi2=50

instead of 10?

ANSWER:NO

now chi2 kill bkgmore effectively

Ondrej – newchi2

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Lchi2 Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

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Lchi2 Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

Ondrej – newchi2

kills bkgmore effectively

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Tchi2Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

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Tchi2Y=1.0-1.5

Y=2.0-2.5

Y=1.5-2.0

black – all tracks frompp min bias file

colored lines are from pi0 only files red photons from pt_pi0=1-1.5 blue photons from pt_pi0=5-5.5 magenta photons from pi0=9-9.5 except y=2-2.5 where its 7.5-8

ln(chi2)

ln(chi2)

ln(chi2)

Ondrej – newchi2

Start thinkingabout cuttingseparatelyon Lchi2and Tchi2

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2 gamma pi0After Edouards new code Dec 2BEFORE Ondrej chi2

Cuts: 0 – chisq<10 1 – eta<1.5 chisq<10 2- pt>200 chisq<10 3- eta<1.5 pt>200 chisq<10

good only fory=1-1.25

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ppmb y=1-1.5

black signal embedded in bkgred – mixed eventsblue – bkg from events with no embedded pi0

pt=1-1.5 cut3 pt=3-3.5 cut3 pt==2-2.5 cut3

signalon full bkg

embeddedevents subtracted

fit

cut is so effectivewe need to runmuch more bkg

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ppmb higher y

black signal embedded in bkgred – mixed eventsblue – bkg from events with no embedded pi0

y=1.5-2 pt=1-1.5 cut2

signalon full bkg

embeddedevents subtracted

fit

y=1.5-2 pt=2-2.5 cut2 y=2-2.5 pt=1-1.5 cut2

as high in ptas we can gofor 2 gamma at y=1.5-2

as high in ptas we can gofor 2 gamma at y=2-2.5

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ppmb :inv yield with error bars, pi0 mean/width

S/B

Central arm pppT/GeV S/B-----------1 1.52 7

y=1-1.5y=1-1.5

pi0mass

pi0width

S/B

pi0mass

pi0width

y=2-2.5

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ppmb eff

y=1-1.5 y=1.5-2.0 y=2.0-2.5

correct pt bin

all pt bins

lowerpt bin

higherpt bin

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dAu mb y=1-1.5

black signal embedded in bkgred – mixed eventsblue – bkg from events with no embedded pi0

pt=1-1.5 cut3 pt=3-3.5 cut3 pt==2-2.5 cut3

signalon full bkg

embeddedevents subtracted

fit

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dAu mb higher y

black signal embedded in bkgred – mixed eventsblue – bkg from events with no embedded pi0

y=1.5-2 pt=1-1.5 cut2y=1.4-2 pt=1.5-3 cut2

signalon full bkg

embeddedevents

subtracted

fit

signalon full bkg

embeddedevents

subtracted

fit

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dAu mb y=1-1.5

S/B

pi0mass

pi0width

eff correct pt bin

eff all pt bins

eff lowerpt bin

efff higherpt bin

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dAu mb y=1.5-2

S/B

pi0mass

pi0width

eff correct pt bin

eff all pt bins

eff lowerpt bin

efff higherpt bin

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dAu cent y=1.0-1.5

signalon full bkg

embeddedevents

subtracted

fit

signalon full bkg

embeddedevents

subtracted

fit

pt=1-1.5 pt=3.5-4

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dAu cent higher y

signalon full bkg

embeddedevents

subtracted

fit

y=1.5-2 pt=1-1.5

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dAu cent y=1.0-1.5

S/B

pi0mass

pi0width

y=1-1.5

eff correct pt bin

eff all pt bins

eff lowerpt bin

efff higherpt bin

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dAu cent 1.5-2.0

S/B

pi0mass

pi0width

y=1-1.5

correct pt bin

all pt bins

lowerpt bin

higherpt bin

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AuAu ~50%

signalon full bkg

embeddedevents

subtracted

fit

signalon full bkg

embeddedevents

subtracted

fit

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AuAu 50% higher y

signalon full bkg

embeddedevents

subtracted

fit

y=1-1.5 pt=1-1.5

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AuAu 50% y=1-1.5

S/B

pi0mass

pi0width

y=1-1.5

correct pt bin

all pt bins

lowerpt bin

higherpt bin

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plans

2 track pi0’s - limited pt range Central ran at ISU last nite – low bkg

statistics (need to make plots) use bigger stats for pp bkg get 500 GeV S/B etc run everything with final cuts Get final R_AA plots out

Big step – merge with single track data