Barbara Betz,

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Jet Propagation Mach Cone Evolution in (31)d
Ideal Hydrodynamics

• Barbara Betz,
• Miklos Gyulassy, Dirk Rischke, Horst Stöcker and
  Giorgio Torrieri

05 / 02 / 08
Yale Columbia Day, Yale University
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Outline

• Motivation Jets in heavy-ion collisions
• Jets in (31)d ideal hydrodynamics
• Different energy-momentum deposition scenarios
• Particle Correlation Pattern
• Conclusions, Outlook Open Questions

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Jets Medium Response

• Jet suppression signal for QGP

• Re-appearance of the away-side for low and
  intermediate pTassoc

• Peaks reflect interaction of jet with medium

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Jets Deposition Scenarios

• Solve numerically (31)d ideal hydrodynamics

• Source term given by jet energy loss
• Different models describing jet energy loss

R. Baier et al., Nucl. Phys. B438, 291 (1997) M.
Gyulassy et al., Nucl. Phys. B571, 197 (2000) J.
Casalderrey-Solana et al., Nucl. Phys. A 774, 577
(2006), arXiv 0705.1352 hep-ph H. Liu et al.,
PRL 97, 182301 (2006) A. Majumder et al., PRL 99,
192301 (2007) T. Renk et al., Phys. Rev. C75,
054910 (2007) G.-Y. Qin et al., Phys. Rev. C76,
064907 (2007) R. Neufeld et al., arXiv 0802.2254
hep-ph
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Deposition Scenarios Hydro

• We use
• Written non-covariantly
• Different deposition scenarios

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Jets in (31)d Ideal Hydro

• Neglect near-side jet

• Study jet evolution in a homogeneous, non
  expanding background

• Bag model EoS for QGP

• Energy-momentum deposition for

• Isochronous freeze-out at

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On-Shell Deposition I

• Peak in jet direction
• Are we done?
• Source unknown
• Distribution function unknown

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On-Shell Deposition II

• Diffusion wake causes
• peak in forward direction
• J. Casalderrey-Solana et al.

J. Casalderrey-Solana et al., Nucl. Phys. A 774,
577 (2006)
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Energy-Momentum Relation
On-shellness
Heisenbergs uncertainty relation
Radiative energy loss
small
large
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Off-Shell Deposition I
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Off-Shell Deposition II
Mach conelike pattern for
Transverse momentum loss
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Pure Energy Loss I
Conelike structure
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Pure Energy Loss II

• Need highpT cuts
• Otherwise thermal smearing washes out signal
  due to high background temperature

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Pure Energy Loss III

• Pure Energy Deposition
• Mach cone pattern

• More pronounced
• higher or pT
• consistent with J. C.-S. et al.

J. Casalderrey-Solana et al., Nucl. Phys. A 774,
577 (2006)
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Conclusions

• Mach cone correlation pattern
• appears only if
• otherwise Diffusion wake kills the Mach
  conelike pattern
• is not visible for cuts similar to experiment if

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Open Questions

• further investigations
• energymomentum deposition scenario
• Transverse momentum loss
• Spatial dependence
• Interaction of jet with medium
• expanding medium
• Radial flow
• Elliptic flow Effect of disentangling?
• Neglecting near-side?