November 2015, GSI, Germany

QCD results on conserved charge fluctuations

and Beam Energy Scan

Swagato Mukherjee

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Baseline ?

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Equilibrium QCD baseline ?

Tf (μBf)

(L)QCD cumulants of conservedcharge fluctuations along:

not a fundamental QCD parameter: expt. input fora given colliding system, phase space cuts, √s …

underlying assumption: expt. observables can be mapped into thermodynamic parameters Tf ,μB

f

use a 'god-given' Tf (μBf )

MQ/σQ2[Mp/σp

2]

OR for consistency: estimate by matching expt. lower cumulants with equilibrium QCD despite all known/unknown caveats

Tf (μBf)

MQ/σQ2 [MB/σB

2 ]

equilibrium QCD baseline for higher cumulants along this Tf (μBf)

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monotonic functions of

√s

μB/T

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μQ=μS=0for simplicity of discussion:

in practice: Ms=0, MQ/MB=0.4 μQ(T ,μB), μS(T ,μB)

MX /σX along the freeze-out line:

χ(T f)= χ(T f , 0)−κ2f (dχ

dT )T f ,0

(μB

T )2

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BNL-Bi-CCNU: arXiv:1509:05786

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BNL-Bi-CCNU: arXiv:1509:05786

155 MeV147 MeV145 MeV

Tf , 0

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BNL-Bi-CCNU: arXiv:1509:05786

T f , 0

κ2f<0.011

slope:

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μQ=μS=κ2f =0

choosing for simplicity:

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μQ=μS=κ2f =0

choosing for simplicity:

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μQ=μS=κ2f =0

choosing for simplicity:

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μQ=μS=κ2f =0

choosing for simplicity:

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