Dynamicalmediumeffectsonjetquenchinginholography
JasmineBrewer
Workdoneincollaborationwith
AndreySadofyev andWilkevanderSchee
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
1
Wanttousejetsasashort-distanceprobeoftheQGP
• complicatedbythepresenceofmanyeffects
??
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
(fig:Schenke,Jeon,Gale1009.3244)
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
2
Manyapproachesforunderstandingthemodificationofjetsinmedium• Perturbativemethods(weakcoupling;quasi-particle
pictureoftheQGP)• Jetsinholography(infinitelystrongcoupling,notQCD)
Thistalk:effectsofadynamicalmediumonjetenergylossinholography• Usualassumptions:evolvingtemperatureandzerovelocity• Goal:qualitativelessonstoinformothercalculations
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
3
localparton energylossfromholography
entirejetdescribedinholography
Holographicmodelsofjetquenching
Hybridmodel Thiswork
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Roadmap
- Introductiontojetsinholography
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
4
- JetenergylossinGubser flow- Effectsofvelocitycanchangestoppingdistancebya
factor> 2- 𝐸 ∼ 𝑥'()*+ -- canbealargeeffect
- Asimplemodelofcoolingplasma- Smallfluidgradientscanhavelargeeffectsondynamics
ofholographicjets
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
5
“Jets”inholography
(fig:AndreySadofyev)
Holographicdirection𝑢
Fallingstring
Dijetpair
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
Introduction JetsinHolography JetsinPlasmaVacuumJets Conclusion
5
“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
7
• Forafinite-sizedplasma,someenergylost,someescapes
(figure:Chesler &Rajagopal 1402.6756)
𝑇*67'17 ∝ 1/𝑢.
𝑢.
Blackhole
vacuum
Trajectoriesofbitofstring’senergy
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
8
QGPisnotastaticslabofplasmaatall
(fig:Schenke,Jeon,Gale1009.3244)
propertime
• Usualassumptions:evolvingtemperatureandzerovelocity
• Whataretheeffectsofadynamicalmediumonjetenergylossinholography?
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
9
Simplestnon-trivialhydrodynamicprofile
“ideal”“viscous”
• Tostudyjets:couplenullgeodesicstohydrodynamicevolution
@µTµ⌫ = 0
Hydrodynamicequations:
Tµ⌫ = �pgµ⌫ + (✏+ p)uµu⌫ +⇧µ⌫“u=0”
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
10
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
12
Gubser flow
Jetsstartingatdifferentpointsinthetransverseplaneexperiencedifferentvelocityfield
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
13
• Velocitygradientsinaholographicpicturehavealargeeffectonenergyloss
u=0
viscous
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion
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Wrap-up
- Velocitygradientsinthefluidcanhavealargeeffectonthequenchingofholographicjets
- ForGubser flow,includingtheeffectsofvelocitygradientssignificantlydecreasesenergyloss
- Outlook:canthiskindofeffectbeseeninothermodels?
Introduction JetsinHolography FlowingPlasmaSimpleModel Conclusion