Dynamical medium effects on jet quenching in holography · 2018-01-31 · Dynamical medium effects...
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Dynamical medium effects on jet quenching in holography Jasmine Brewer Work done in collaboration with Andrey Sadofyev and Wilke van der Schee Introduction Jets in Holography Flowing Plasma Simple Model Conclusion
Transcript of Dynamical medium effects on jet quenching in holography · 2018-01-31 · Dynamical medium effects...
Dynamicalmediumeffectsonjetquenchinginholography
JasmineBrewer
Workdoneincollaborationwith
AndreySadofyev andWilkevanderSchee
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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Wanttousejetsasashort-distanceprobeoftheQGP
• complicatedbythepresenceofmanyeffects
??
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
(fig:Schenke,Jeon,Gale1009.3244)
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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Manyapproachesforunderstandingthemodificationofjetsinmedium• Perturbativemethods(weakcoupling;quasi-particle
pictureoftheQGP)• Jetsinholography(infinitelystrongcoupling,notQCD)
Thistalk:effectsofadynamicalmediumonjetenergylossinholography• Usualassumptions:evolvingtemperatureandzerovelocity• Goal:qualitativelessonstoinformothercalculations
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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localparton energylossfromholography
entirejetdescribedinholography
Holographicmodelsofjetquenching
Hybridmodel Thiswork
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Roadmap
- Introductiontojetsinholography
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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- JetenergylossinGubser flow- Effectsofvelocitycanchangestoppingdistancebya
factor> 2- 𝐸 ∼ 𝑥'()*+ -- canbealargeeffect
- Asimplemodelofcoolingplasma- Smallfluidgradientscanhavelargeeffectsondynamics
ofholographicjets
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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“Jets”inholography
(fig:AndreySadofyev)
Holographicdirection𝑢
Fallingstring
Dijetpair
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
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“Jets”inholography
(fig:AndreySadofyev)
Holographicdirection𝑢
Fallingstring
Dijetpair
Blackhole
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
6 (figures:Chesler &Rajagopal 1511.07567)
𝑥/𝑥(./01
Boundary(fieldtheory)
Blackholehorizon
Trajectoryofstringendpoint
Trajectoriesofbitofstring’senergy
𝜋𝑇𝑥(./01
𝜎0
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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• Forafinite-sizedplasma,someenergylost,someescapes
(figure:Chesler &Rajagopal 1402.6756)
𝑇*67'17 ∝ 1/𝑢.
𝑢.
Blackhole
vacuum
Trajectoriesofbitofstring’senergy
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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QGPisnotastaticslabofplasmaatall
(fig:Schenke,Jeon,Gale1009.3244)
propertime
• Usualassumptions:evolvingtemperatureandzerovelocity
• Whataretheeffectsofadynamicalmediumonjetenergylossinholography?
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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Simplestnon-trivialhydrodynamicprofile
“ideal”“viscous”
• Tostudyjets:couplenullgeodesicstohydrodynamicevolution
@µTµ⌫ = 0
Hydrodynamicequations:
Tµ⌫ = �pgµ⌫ + (✏+ p)uµu⌫ +⇧µ⌫“u=0”
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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Thetrajectoryofnullgeodesicsareverysensitivetogradientsinthehydrodynamicevolution
• Evenforfairlysmallgradients,geodesicsinidealhydroaresick,since
cancelsinviscouscase
@2u
@t2
����t=0
=
“ideal”
“viscous”
@
2u
@t
2
����t=0
= �@v
x
@x
+ 2 (⇡T )4 u3in
+O(@3)
2 (⇡T )4 u3in
✓1 +O
✓1
⇡T
@v
x
@x
◆◆+O(@3)
⇡Tuin ⇠ 0.01
(𝐸:/( ∼ 𝑢;<=+)
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
11 (Gubser 1006.0006)
QGPisnotastaticslabofplasmaorasimplesystem• WhataretheeffectsofadynamicalQGP-likemediumonjet
energylossinholography?
Example:Gubser flow
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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Gubser flow
Jetsstartingatdifferentpointsinthetransverseplaneexperiencedifferentvelocityfield
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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• Velocitygradientsinaholographicpicturehavealargeeffectonenergyloss
u=0
viscous
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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Wrap-up
- Velocitygradientsinthefluidcanhavealargeeffectonthequenchingofholographicjets
- ForGubser flow,includingtheeffectsofvelocitygradientssignificantlydecreasesenergyloss
- Outlook:canthiskindofeffectbeseeninothermodels?
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
