Craig Ogilvie, Iowa State University On behalf of the PHENIX Collaboration Heavy flavor systematics…

cogilvie@iastate.edu

Craig Ogilvie, Iowa State UniversityOn behalf of the PHENIX Collaboration

Heavy flavor systematics from PHENIX

Sep 27, 20131

• Complexity of interpreting data from HI collisions• Use systematics: spectra, elliptic flow,…• Present d+Au, Cu+Cu, excitation function,…

• Which leads to the complexity of interpreting d+Au…

cogilvie@iastate.edu

Complexity of d(p)+A collisions

Sep 27, 20132

Nuclear structure functionsShadowing, saturation at low-xAnti-shadowing at moderate, high-x

Initial state scatteringOften modeled as increase in effective kTLikely largest impact at RHIC where spectra are softer

Possible collective effectsBarbara Jacak’s talk on Wed

Final state energy-loss, absorption,….Centrality classification

cogilvie@iastate.edu

CNM I: d+Au heavy-flavor at 200 GeV

Sep 27, 20133

Non-photonic e, from heavy-flavor decays Phys. Rev. Lett. 109, 242301 (2012) , Significant enhancement

at moderate pT

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CNM II: d+Au heavy-flavor at 200 GeV

Sep 27, 20134

Non-photonic e, from heavy-flavor decays

Phys. Rev. Lett. 109, 242301 (2012)

Enhancement present in min-biasEffect not caused by challenges of centrality definition

RdA

PT (GeV/c)

cogilvie@iastate.edu

CNM IV: Forward, backward m from HF decay

Sep 27, 20135

m me

Forward rapidity suppressedLikely shadowing at low-x in Au

Backward rapidity enhancedanti-shadowing at higher x in Au?or increase in <kT> due to initial scattering?

cogilvie@iastate.edu

CNM III: Identified hadron spectra in dA

Sep 27, 20136

Phys. Rev. C 88, 024906 (2013)

Cronin peak: proton ~ > HFe

Why?

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RdA

PT (GeV/c)

CNM II: d+Au heavy-flavor at 200 GeV

Sep 27, 20137

Phys. Rev. Lett. 109, 242301 (2012)

Does <kT> increase have larger impact when p+p spectrum is soft?spectra = convolution of scattering + fragmentation

Or recombination effects in hadronization? Or collective? Or…Opportunity for theory impact

cogilvie@iastate.edu

Example with p0 RdA

Sep 27, 20138

p0 calc from I. VitevReasonable reproduction of p0

Nuclear structure functionCronin

Large initial state multiple-scattering

Final state Eloss Need calculations for heavy-

flavor RdA

Vitev et al., PRD 74 (2006)Phys.Lett. B718 (2012) 482-487

J/y CNM

Sep 27, 20139 y

EPS09 nuclear structure functions plus breakupReasonable reproduction, misses centrality dependence

BUT, charm is enhanced at moderate pT

(non-photonic electrons RdA>1)

1) Do these calculations reproduce open charm RdA >1 ?

2) If not, then more effective suppression needed for J/y

PRL 107, 142301 (2011)

Normalize J/y by HF?

Sep 27, 201310

J/y at mid-y suppressed @low-pt

Charm is enhanced at moderate pt (non-photonic electrons RdA>1)

Alternative: use dA HF spectra as baseline?

• Question, what axis? pT ?RdA

PT (GeV/c)

J/y

Phys. Rev. C 87, 034904 (2013)

Au-going, high-x

d-going, low-x

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Connect d+Au to A+A

Sep 27, 201311

Phys. Rev. Lett. 109, 242301 (2012) ,

1) Enhancement in d+Au + energy-loss suppression in A+A2) Models must attempt to reproduce both d+A and A+A

Min-bias collisions

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One method to organize results

Sep 27, 201312

Phys. Rev. Lett. 109, 242301 (2012) , Matt Durham

Common suppression pattern when normalized by square of RdA

Does this take into account impact of initial state increase of <kT>?

cogilvie@iastate.edu

Intermediate Cu+Cu: links d+A and Au+Au

Sep 27, 201313

Peripheral Cu+Cu (yellow)Enhancement ~ central d+Au (blue)

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d+Au to Cu+Cu to Au+Au

Sep 27, 201314

Interplay of two effectsCNM increases yield, competes with energy-loss suppression

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d+Au to Cu+Cu to Au+Au

Sep 27, 201315

Higher pTCNM increases yield, stronger energy-loss suppression

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dAu

Cu+Cu heavy-flavor, forward rapidity

Sep 27, 201316

Large uncertainties: Forward y in central d+Au ~ peripheral Cu+Cu

Cu+Cu forward y, Au+Au mid-rapidity

Additional lever arm: beam energy

Sep 27, 201317

Dominant energy-loss at high s Transitions to stronger Cronin effect at lower s

pT (GeV/c)

charged hadrons from Au+Aup0 Phys. Rev. Lett. 109, 152301 (2012)

cogilvie@iastate.edu

Need RdA at lower-beam energy

Sep 27, 201318

Not in current RHIC running plan :(How does RdA change from 200 GeV to 62 GeV Three beam energies (62, 200 GeV, LHC) constrains interplay

of structure function, initial state scatteringRdA calculations at 62 GeV

p RdA ~ 2 at 62 GeV p RdA ~ 1.2 at 200 GeV

A. Accardi Eur. Phys. J. C 43, 121–125 (2005)

Non-photonic electrons Au+Au 62 GeV

Sep 27, 201319

Lower beam energy changes interplay of two effectsStronger CNM competing with weaker energy-loss

Forthcoming PHENIX publicationspectra with smaller systematicscomparison with p+p, RAA etc.

If your model reproduces 200 GeV and 2.76 TeV heavy flavor RAA

Final call for 62 GeV HF RAA prediction

cogilvie@iastate.edu

HF v2 at lower beam energy

Sep 27, 201320

HF flow is > 0 at 62 GeV, but uncertainties large

cogilvie@iastate.edu

V2 2nd constraint on e-loss Au+Au 200 GeV

Sep 27, 201321

Low-pt Charm v2, extent of thermalization of HFChallenge for theory to reproduce both RAA, v2

Many calculations, theory updates past few years

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One example, P.B. Gossiaux SQM 2013

Sep 27, 201322

Elastic + radiative energy lossWith running coupling a

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Is dpT/pT what we should be plotting for HF?

Sep 27, 201323

PRC 87, 034911 (2013)

Suggestion in spirit of workshop, This is being worked on for HF, but no results available yet

cogilvie@iastate.edu

VTX Upgrade @ PHENIXTwo layers of silicon pixel detectorsTwo layers of silicon strip detectorsFour layers in endcapsTracks extrapolate back to collision vertexDisplaced vertices charm (D), beauty (B)Requires ~ 50 mm precision

De+X Au

e

Au

X

B e+X

Xp0 e+e- ee

Sep 27, 201324

Installed 2010-12

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VTX p+p results

Sep 27, 201325 2012/10/23

charm/bottom assumes PYTHIA spectra

DCA data are fit by expected DCA shapes of • Signal components : c e and b e (right column)• Background components (left column)

Fit range : 0.2<|DCA|<1.5(mm)

b/(b+c)=0.22+-0.06

cogilvie@iastate.edu

VTX p+p results

Sep 27, 201326 2012/10/23

FONLL consistent with b/(b+c) data

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Physics Goal

Sep 27, 201327

Energy-loss heavy-flavor understand nature of sQGPProgress on understanding many detailsIf a model reproduces a broad range of data

Can we infer any characteristics of QGP?Either direct via a parameter of model

Diffusion parameterOr run same dynamical model in a “box”, e.g. radiation +

collision Eloss

Infer effective transport parametersWhich characteristics of sQGP are accessible this way and can we

communicate this to our fellow physicists?Maybe too many unsettled aspects yet

cogilvie@iastate.edu

Summary

Sep 27, 201328

Complexity of interpreting d+AuLevers: centrality, A, y, s, change impact of

Structure function, initial state scattering, e-loss,…HF RdA enhancement up to factor of 1.5

Call for model calculationsIs dAu HF a better baseline for RAA HF and dAu J/y

production?? Complexity of interpreting data from HI collisions

Cu+Cu HF yields smoothly connects dAu to Au+AuCompetition between enhancement + suppression

Change this competitionAu+Au HF data @ 62 GeV, need dAu running at 62 GeV

cogilvie@iastate.edu

Backup slides

Sep 27, 201329

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X-ranges

Sep 27, 201330

SPSPb+Pb17 GeV

RHIC Au+Au200 GeV

LHC Pb+Pb5.5 TeV

c-cbar X~10-1 X~10-2 X~10-3 to 10 -4

Eskola et al. JHEP 0904 (2009) 065

cogilvie@iastate.edu

RAA of heavy-flavor: from RHIC to LHC

Sep 27, 201331

Note to Craig add citations

cogilvie@iastate.edu Sep 27, 201332

cogilvie@iastate.edu

Charm production at 62 GeV reproduced by FONLL

Sep 27, 201333

cogilvie@iastate.edu Sep 27, 201334

cogilvie@iastate.edu Sep 27, 201335

cogilvie@iastate.edu

Less bound charmonia in dAu collisions

Sep 27, 201336

arXiv:1305.5516

All three systems consistent within uncertainties

cogilvie@iastate.edu

Less bound charmonia in dAu collisions

Sep 27, 201337

arXiv:1305.5516

y’ suppression stronger than J/y for more central dAu collisionsStronger effective breakup cross-section?

cogilvie@iastate.edu

Photon in dA

Sep 27, 201338

Phys.Lett. B718 (2012) 482-487