Moments update Click to edit Master subtitle style Bulkcorr PWG meeting, June 26, 2013 1 update on...

moments update

Click to edit Master subtitle style

Bulkcorr PWG meeting, June 26, 2013 1

update on moments & sampled singlesw.j.llope

bulkcorr PWG, June 26, 2014

Independent code that reads 4 TH2Ds (net-X, tot-X, X, Xbar) vs rmNcorr at all 7 √sNN… TH2Ds for X=p from xiaofeng luo (net-p paper),

X=p, q, K from daniel mcdonald (q and K at QM 2012)

produces:moments from data, & (N)BD and ``sampled singles” baselines

http://wjllope.rice.edu/fluct/protected/moments_20130417.pps

now calculating sampled singles uncertainties from delta theoremnow applying efficiency corrections to XFL’s net-p results

working towards efficiency corrections (including tof match eff!) for dmac’s results_________________________________________________________________________

Outlineoverview of (N)BD and sampled singles baseline approachesXFL net-p, with and without efficiency correctiondmac net-p, net-q, and net-K, then efficiency corrections to dmac net-q using nihar efficienciescomparison of dmac net-p and XFL net-p

moments update



STAR Results (QM2012)

√sNN <mB>*

7.7 421

11.5 316

19.6 206

27 156

39 112

62.4 73

200 24 * C

leym

ans

et a

l. P

RC

73,

034

905

(200

6)

net-protonsX. Luo for STAR, QM2012

D. McDonald for STAR, QM2012

net-charge net-K

No non-monotonicity seen

Significance of net-p dip?

moments update



(N)BD

T..J. Tarnosky & G. Westfall, Oct. 2012 http://arxiv.org/pdf/1210.8102v1.pdf

Functional form describes the (particle identified) multiplicity distributions ranging from NA22 & UA5 to PHENIX

Inputs:mean (μ) &variance (σ2)

Then, the values of Ck , Sσ , & Kσ2 are predicted.

moments update



“Sampled Singles”

Sampled Singles is not “mixed events”

The only input is the 2D distributions of Npos vs. rmNcorr and Nneg vs. rmNcorr.where pos = p, K+, q+ and neg = pbar, K-, q-

same plots for K±, q±

Filled at the same spot in analysis codes where the deviates are saved……i.e. includes all the same track cuts, PID, and run&evtQA as the independentanalysis…

Np

N

pbar

7.7 11.5 19.6 27 39 62.4 200

refmultNcorr

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Sampled Singles method

In every slice of rmNcorr, sample one value of Npos and one value of Nneg, Nevt times.

In each sampled event at a given rmNcorr, one then has a value for Npos and NnegThen form Nnet = Npos-Nneg and Ntot = Npos+NnegFill 2D plots of Nnet and Ntot vs. refmultNcorrThen extract the moments (products) with the CBW corrections as usual…

Destroys all intra-event correlations between Npos and Nneg, reproduces singles distributions, & has the same statistical certainty as the data, by construction…

Np

N

pbar 7.7 11.5 19.6 27 39 62.4 200

refmultNcorr

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Sampled Singles method: Oversampling

Approach used up to a ~1 week ago sampled NEVT times for a given slice of refmultNcorr.

Was observed however that the resulting CBW-corrected moments products had a noticeable variance (lowest root-s generally) with the choice of TRandom3 seed…

This is not physical but canbe fixed easily with only expensebeing CPU time…

Now sample each slice (pos or neg)NREPEATS*NEVT times and fillresulting Nnet and Ntot TH1Ds witha weight of 1/NREPEATS

Same statistical uncertaintiesSame moments uncertainties (Δ thm.)Stable sampled singles results

will now show some plots forNREPEATS = 1,2,4,8,36,49,81

moments update




RMS of SampSing <Kσ2> values vs NREPEATS by root-s

RMS(<Kσ2>) decreases with increasing root-s, and with decreasing centrality at any NREPEATSIncreasing NREPEATS decreases RMS as a power law.. Values stable for NREPEATS ≥ ~36

0.1

0.01

0.001

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SampSing err(<Kσ2>) vs NREPEATS by root-s

0.1

0.01

0.001

0.0001

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Delta theorem’s Kσ2 uncertainty for many runs with NREPEATS=1

Average value of Δ-thmuncertainty exactly reproduces that from dataeven for NREPEATS=1

But there is some variance.largest at lowest root-s.

moments update




Delta theorem’s Kσ2 uncertainty for many runs with NREPEATS=36

Average value of Δ-thmuncertainty still reproduces that from data

Variance in SampSinguncertainty now tiny.

moments update



Sampled Singles / Data comparisons

Oversampling makes the sampled singles results much more stable.Code now takes an hour to run on my laptop, not ~3 minutes as

before…

Now turn to comparisons to Xiaofeng’s net-p results (net-p paper).

Efficiency corrections performed to both data and sampled singles.Efficiencies are charge-independent and are taken from the analysis

note. Note eff(39) = eff(62) = eff(200) was assumed

Corrected cumulants depend on Ck(net), Ck(tot), Ck(pos), Ck(neg), Npos, & Nneg

moments update



Uncorrected net-p Sσ vs. centrality by root-s

cyan bands are sampled singlesuncertainties from delta theorem

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Uncorrected net-p Kσ2 vs. centrality by root-s

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Uncorrected net-p Sσ & Kσ2 vs. root-s for 0-5%

very good agreement to Xiaofeng’suncorrected results in general, except 200(some v. slight differences at lowest root-s)

Sampled Singles reproduces the data values…(N)BD also does a good job for net-p…

Note:TH2Ds from Xiaofengat 200GeV include 40Mevents, plots in net-p paperhave 240M events.

moments update



Now, perform the efficiency corrections…

Sσ vs centrality by root-s

Kσ2 vs centrality by root-s7.7 11.5 19.6 27 39 62.4 200

open: uncorrectedsolid: corrected

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Efficiency-corrected Sσ & Kσ2 with the Sampled Singles values



measured(WJL)measured(XFL)sampled singles

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Efficiency-corrected Sσ & Kσ2 with the Sampled Singles values

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Now…

switch over from XFL net-p data to

dmac net-p,net-q,net-K data

moments update



Uncorrected dmac net-p Sσ vs. centrality by root-s

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Uncorrected dmac net-p Kσ2 vs. centrality by root-s

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Uncorrected dmac net-p Kσ2 vs. root-s for 0-5%

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Uncorrected dmac net-q Kσ2 vs. centrality by root-s

(N)BD and SampSingsimilar for 39 and below

SampSing blows upfor 62.4 and 200 andexcept for peripheral…

moments update



Sampled singles net-q central at highest root-s!

Same events!Intra-event correlations are important…

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Uncorrected dmac net-q Kσ2 vs. root-s for 0-5%

Intriguing that sampled singles ~reproduces the data for 39 GeV and below.What turns on between 39 and 62.4?!?

moments update



Uncorrected dmac net-K Sσ vs. centrality by root-s

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Uncorrected dmac net-K Kσ2 vs. centrality by root-s

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Uncorrected dmac net-K Kσ2 vs. root-s for 0-5%

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Efficiency corrections to dmac net-q (using nihar’s chg-independent eff.’s)



open: uncorrectedsolid: corrected

unlike net-p (slide 15), corrected net-q valuesare larger than the uncorrected values

moments update



Summary

Completely independent analysis code for data, sampled singles, and (N)BD.Now including sampled singles uncertainties (Δ-thm) and some efficiency corrections.

Oversampling makes the sampled singles results stable for different TRandom3 seeds.

Sampled singles approaches and (N)BD compared to XFL’s net-p paper data.Sampled singles accurately reproduces the moments values from the data.~no (impact from) intra-event correlations (on these observables) for net-p.

Sampled singles curves based on net-p paper data provided to Xiaofeng.net-p paper GPC is presently discussing whether to show these in the net-p paper.

Same comparisons done for dmac’s net-p, net-K, and net-q results.~no (impact from) intra-event correlations (on these observables) for net-K.Strong (impact from) intra-event correlations (on these observables) for net-q and √sNN≥62.4.

PlansI now have all embedding data for π±, K±, p and pbar at all BES root-s values…Presently calculating the π± and K± tofmatch efficiencies (p,pbar already in hand)Will allow me to efficiency-correct dmac net-p, net-q, & net-K data…

moments update



Uncorrected net-p Sσ vs. centrality by root-s, Comparison

SampSing not oversampled

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Uncorrected net-p Kσ2 vs. centrality by root-s, Comparison

SampSing not oversampled

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Uncorrected net-p Sσ & Kσ2 vs. root-s, 0-5%, Comparison

Ks2

Ss

root-s

Despite widely different acceptances (~50% in <net-p> at 7.7) the present dE/dx-onlyanalysis and the RICE “requiring TOF” give the same answer for 0-5% collisions.

this is kind-ofamazing to me.

moments update



BACKUP SLIDES

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Net-K

sampled singles uncertainties are notdrawn, but are similar to those onthe data points by construction…

moments update



Net-Q

Sampled singles values gobeserk for ~central events atthe highest √sNN….

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Net-p

sampled singles approachreproduces the net-p moments for all √sNN & centrality…

moments update



Net-p vs. √sNN, 0-10% central

moments update



Present net-p paper values w/ and w/out efficiency correction.

Moments update Click to edit Master subtitle style Bulkcorr PWG meeting, June 26, 2013 1 update on...

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