Bottomonium suppression in the quark-gluon plasma Michael - - PowerPoint PPT Presentation

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Bottomonium suppression in the quark-gluon plasma Michael - - PowerPoint PPT Presentation

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Bottomonium suppression in the quark-gluon plasma Michael Strickland Kent State University Kent, OH USA Sharif University of Technology July 14, 2020 Quarks are normally confined inside hadrons HADRONS Baryons Mesons Gluons

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SLIDE 1

Bottomonium suppression in the quark-gluon plasma

Michael Strickland

Kent State University Kent, OH USA

Sharif University of Technology July 14, 2020

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SLIDE 2

Quarks are normally “confined” inside hadrons

Baryons Mesons HADRONS

Gluons hold the quarks together

… …

  • M. Strickland

2

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SLIDE 3

Quarks and anti-quarks

Name Mass [GeV/c2] Electric Charge Up u 0.0024 +2/3 Down d 0.0048

  • 1/3

Strange s 0.104

  • 1/3

Charm c 1.27 2/3 Bottom b 4.2

  • 1/3

Top t 171.2 2/3

  • Quarks are fermions (spin ½);

have electric charge and “color charge”

  • There are also anti-quarks that have the opposite

electric charge and “anti-color charge”

  • The proton is (primarily) composed of uud
  • Compare the masses above to the mass of the

proton which is ~ 1 GeV

Diagram Symbol

quark antiquark flow of time q q

Blue Red Green Anti-Red Anti-Blue Anti-Green “Colorless”

  • M. Strickland

3

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SLIDE 4
  • M. Strickland

4 Color ionized plasma

Melting hadrons

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SLIDE 5
  • M. Strickland

5

Quantum chromodynamics (QCD) phase diagram

Crossover First Order Second Order

200 MeV à 2 x 1012 K

Tc ~ 154 MeV

T [MeV]

Color Superconductor

100 200 300 1000 Hadron Gas

Nuclear Matter

Quark Gluon Plasma

Quark Matter

Vacuum

μ [MeV]

B

300 600 900 1200 1500 Quark-Gluon Plasma

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SLIDE 6

1 loop αs ;

MS

176 MeV μB 0 MeV

200 400 600 800 1000 0.0 0.2 0.4 0.6 0.8 1.0 T MeV

ideal

Wuppertal Budapest NNLO HTLpt

6

Pressure vs temperature – µB = 0 MeV

  • M. Strickland

No fit parameters!

Andersen, Leganger, Su, and MS 1009.4644, 1103.2528

  • N. Haque, J.O. Andersen, M.G. Mustafa, MS, N. Su, 1309.3968

Hadron Resonance Gas Quark Gluon Plasma

RHIC 200 GeV LHC 5.023 TeV LHC 2.76 TeV

Resummed perturbation theory (Strickland et al) Lattice QCD (Wuppertal-Budapest group)

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SLIDE 7
  • M. Strickland

7

QCD phase diagram

Crossover First Order Second Order

200 MeV à 2 x 1012 K

Tc ~ 154 MeV

T [MeV]

Color Superconductor

100 200 300 1000 Hadron Gas

Nuclear Matter

Quark Gluon Plasma

Quark Matter

Vacuum

μ [MeV]

B

300 600 900 1200 1500

neutron stars supernovae

LHC 5.023 TeV à T0 ~ 700 MeV LHC 2.76 TeV à T0 ~ 600 MeV RHIC 200 GeV à T0 ~ 400 MeV

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SLIDE 8

98% of the mass in the universe is made during the QGP transition

  • The Higgs boson only provides a small

fraction of the mass of observed hadronic matter.

  • Most of the mass around us emerges

from the strong force.

  • M. Strickland

8

Bashir et al, Commun. Theor. Phys. 58 (2012) 79-134.

Logarithmic scale

Figure courtesy B. Muller

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SLIDE 9

Experiments and Phenomenology

  • M. Strickland

9

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SLIDE 10

Ultrarelativistic heavy-ion collisions

  • RHIC, BNL – Au-Au @ 200 GeV/nucleon (highest energy) à T0 ∼ 400 MeV
  • LHC, CERN – Pb-Pb @ 2.76 TeV à T0 ∼ 600 MeV
  • LHC, CERN – Pb-Pb @ 5.03 TeV à T0 ∼ 700 MeV
  • RHIC, BNL BES – Au-Au @ 7.7 - 39 GeV à T0 ∼ 30-100 MeV [+finite density]
  • FAiR (GSI), NICA (Dubna) – U-U @ 35 GeV -> T0 ∼ 100 MeV [+finite density]
  • M. Strickland

10

200 MeV à 2 x 1012 K

~ 10-14 m Entire event lasts ~ 10 fm/c which is ~ 3 x 10-23 s !!!

T = 200 MeV à 2 x 1012 K

~ 10-14 m Entire event lasts ~ 10 fm/c which is ~ 3 x 10-23 s !!!

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SLIDE 11

Ultrarelativistic heavy-ion collisions

  • RHIC, BNL – Au-Au @ 200 GeV/nucleon (highest energy) à T0 ∼ 400 MeV
  • LHC, CERN – Pb-Pb @ 2.76 TeV à T0 ∼ 600 MeV
  • LHC, CERN – Pb-Pb @ 5.03 TeV à T0 ∼ 700 MeV
  • RHIC, BNL BES – Au-Au @ 7.7 - 39 GeV à T0 ∼ 30-100 MeV [+finite density]
  • FAiR (GSI), NICA (Dubna) – U-U @ 35 GeV -> T0 ∼ 100 MeV [+finite density]
  • M. Strickland

11

200 MeV à 2 x 1012 K

~ 10-14 m Entire event lasts ~ 10 fm/c which is ~ 3 x 10-23 s !!!

T = 200 MeV à 2 x 1012 K

~ 10-14 m Entire event lasts ~ 10 fm/c which is ~ 3 x 10-23 s !!!

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SLIDE 12

Some Key Experimental Observables

  • Collective Flow – flow of the matter provides evidence of collectivity in the QGP

and allows us to extract transport coefficients like the shear viscosity

  • Jet Quenching – effects of plasma interactions on high-energy particle

propagation; provides information about momentum diffusion and energy loss of partons in the QGP

  • Suppression of heavy quarkonia – provides information about screening and

bound state survival in the QGP

  • Electromagnetic Radiation – high energy photons and dileptons provide

information about initial conditions

  • Particle spectra across species – provides information about the degree to which

final particle distributions are thermalized

  • Multiparticle correlations such as Hanbury-Brown-Twiss (HBT) interferometry –

provides information about the size of the QGP and collective flow profiles

12

  • M. Strickland
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SLIDE 13

Some Key Experimental Observables

  • Collective Flow – flow of the matter provides evidence of collectivity in the QGP

and allows us to extract transport coefficients like the shear viscosity

  • Jet Quenching – effects of plasma interactions on high-energy particle

propagation; provides information about momentum diffusion and energy loss of partons in the QGP

  • Suppression of heavy quarkonia – provides information about screening and

bound state survival in the QGP

  • Electromagnetic Radiation – high energy photons and dileptons provide

information about initial conditions

  • Particle spectra across species – provides information about the degree to which

final particle distributions are thermalized

  • Multiparticle correlations such as Hanbury-Brown-Twiss (HBT) interferometry –

provides information about the size of the QGP and collective flow profiles

13

  • M. Strickland
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SLIDE 14

Why heavy quarkonia?

  • M. Strickland

14

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SLIDE 15

What is bottomonia?

  • M. Strickland

15

E288 exp @ Fermilab, 1977

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SLIDE 16

Why bottomonia?

  • M. Strickland

16

Vacuum decay lifetime = 3654 fm/c ~ 10-20 s Vacuum bindng energy of Y(1s) is ~ 1 GeV

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SLIDE 17
  • M. Strickland

17 Color ionized plasma

Melting hadrons – conceptual correction

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SLIDE 18
  • Can reliably use heavy quark effective theory
  • Cold nuclear matter (CNM) effects in AA

decrease with increasing quark mass

  • The masses of bottomonia (~ 10 GeV) are

much higher than the temperature (T < 1 GeV) generated in HICs à bottomonia production dominated by initial hard scatterings

  • Since bottom quarks and anti-quarks are relatively rare in LHC

HICs, the probability for regeneration of bottomonia through statistical recombination is much smaller than for charm quarks [see e.g. E. Emerick, X. Zhao, and R. Rapp, arXiv:1111.6537]

Why bottomonia in AA?

  • M. Strickland

18

  • A. Mocsy, P. Petreczky,

and MS, 1302.2180

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SLIDE 19

Heavy quark effective theory

  • Normally, for QCD bound

states one needs a fully relativistic treatment

  • If the quark mass is

sufficiently high then one can take the “heavy quark limit”

  • This reduces the problem to

having to deal with a non- relativistic terms plus relativistic corrections

  • M. Strickland

19

Name Mass [GeV/c2] Electric Charge Up u 0.0024 +2/3 Down d 0.0048

  • 1/3

Strange s 0.104

  • 1/3

Charm c 1.27 2/3 Bottom b 4.2

  • 1/3

Top t 171.2 2/3

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SLIDE 20

How well does this work?

  • M. Strickland

20

  • J. Alford and MS, 1309.3003
  • As the table to the right

shows, it works quite well

  • Maximum error in the

masses of the bottomonium sates is 0.22%

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SLIDE 21

21

Debye-screening in a plasma

Screening of electric interaction with screening length rD = 1/mD

VColoumb(r) = −α r − → VDebye(r) = −α r e−mDr

A test charge polarizes the particles of the plasma and they “screen” its charge

  • M. Strickland

Peter Debye 1884 - 1966

  • The same phenomena that occurs in an

electric plasma occurs in the QGP

  • A screening mass mD ~ gT is generated by

strong interactions of quarks and gluons

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SLIDE 22

22

Debye-screening in a plasma

  • M. Strickland

Coloumb Debye-screened

1 2 3 4 5

  • 5
  • 4
  • 3
  • 2
  • 1

r V

VColoumb(r) = −α r − → VDebye(r) = −α r e−mDr

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SLIDE 23

23

Debye-screening in a plasma

  • M. Strickland

Coloumb Debye-screened

1 2 3 4 5

  • 5
  • 4
  • 3
  • 2
  • 1

r V

VColoumb(r) = −α r − → VDebye(r) = −α r e−mDr

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SLIDE 24

24

Debye-screening in a plasma

  • M. Strickland

Coloumb Debye-screened

1 2 3 4 5

  • 5
  • 4
  • 3
  • 2
  • 1

r V

VColoumb(r) = −α r − → VDebye(r) = −α r e−mDr

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SLIDE 25

In-medium breakup (decay) rates

  • In addition to Debye screening, which reduces the

effective coupling between quarks and antiquarks, the states also acquire a temperature dependent breakup rate (width) which increases as the temperature increases.

  • Primarily, heavy quark bound states breakup via

strong processes which result in the quark/antiquark becoming unbound inside of the QGP, e.g. Landau damping, collisional disassociation, etc.

  • M. Strickland

25

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SLIDE 26

In-medium heavy quark potential

Anisotropic potential calculation: Dumitru, Guo, and MS, 0711.4722 and 0903.4703 Gluon propagator in an anisotropic plasma: Romatschke and MS, hep-ph/0304092

Using the real-time formalism one can express the potential in terms of the static advanced, retarded, and Feynman propagators Real part can be written as With direction-dependent masses, e.g.

V (r, ξ) = −g2CF Z d3p (2π)3 (eip·r − 1)1 2 ⇣ D∗L

R + D∗L A + D∗L F

⌘

Re[V (r, ξ)] = −g2CF Z d3p (2π)3 eip·r p2 + m2

α + m2 γ

(p2 + m2

α + m2 γ)(p2 + m2 β) − m4 δ

26

  • M. Strickland
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SLIDE 27

Complex-valued Potential

  • Anisotropic potential can

be parameterized as a Debye-screened potential with a direction-dependent Debye mass

  • The potential also has an

imaginary part coming from the Landau damping

  • f the exchanged gluon!
  • This imaginary part also

exists in the isotropic case

Laine et al hep-ph/0611300

  • Used this as a model for

the free energy (F) and also obtained internal energy (U) from this.

Dumitru, Guo, Mocsy, and MS, 0901.1998 MS, 1106.2571; Bazow and MS, 1112.2761 Dumitru, Guo, and MS, 0711.4722 and 0903.4703 Burnier, Laine, Vepsalainen, arXiv:0903.3467 (aniso)

27

  • M. Strickland

Internal Energy

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SLIDE 28

Heavy Quarkonium Suppression

  • M. Strickland

28 cartoon

  • In a high temperature quark-gluon plasma we

expect weaker color binding (Debye screening + asymptotic freedom)

  • E. V. Shuryak, Phys. Rept. 61, 71–158 (1980)
  • T. Matsui, and H. Satz, Phys. Lett. B178, 416 (1986)
  • F. Karsch, M. T. Mehr, and H. Satz, Z. Phys. C37, 617 (1988)
  • Also, high energy plasma particles which slam into

the bound states cause them to have shorter lifetimes à larger spectral widths

  • A. Bazavov and P. Petreczky, 1211.5638

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 29

Heavy Quarkonium Suppression

  • M. Strickland

29 cartoon

  • In a high temperature quark-gluon plasma we

expect weaker color binding (Debye screening + asymptotic freedom)

  • E. V. Shuryak, Phys. Rept. 61, 71–158 (1980)
  • T. Matsui, and H. Satz, Phys. Lett. B178, 416 (1986)
  • F. Karsch, M. T. Mehr, and H. Satz, Z. Phys. C37, 617 (1988)
  • Also, high energy plasma particles which slam into

the bound states cause them to have shorter lifetimes à larger spectral widths

  • A. Bazavov and P. Petreczky, 1211.5638

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 30

Heavy Quarkonium Suppression

  • M. Strickland

30 cartoon

  • In a high temperature quark-gluon plasma we

expect weaker color binding (Debye screening + asymptotic freedom)

  • E. V. Shuryak, Phys. Rept. 61, 71–158 (1980)
  • T. Matsui, and H. Satz, Phys. Lett. B178, 416 (1986)
  • F. Karsch, M. T. Mehr, and H. Satz, Z. Phys. C37, 617 (1988)
  • Also, high energy plasma particles which slam into

the bound states cause them to have shorter lifetimes à larger spectral widths

  • A. Bazavov and P. Petreczky, 1211.5638

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 31

Heavy Quarkonium Suppression

  • M. Strickland

31 cartoon

  • In a high temperature quark-gluon plasma we

expect weaker color binding (Debye screening + asymptotic freedom)

  • E. V. Shuryak, Phys. Rept. 61, 71–158 (1980)
  • T. Matsui, and H. Satz, Phys. Lett. B178, 416 (1986)
  • F. Karsch, M. T. Mehr, and H. Satz, Z. Phys. C37, 617 (1988)
  • Also, high energy plasma particles which slam into

the bound states cause them to have shorter lifetimes à larger spectral widths

  • A. Bazavov and P. Petreczky, 1211.5638

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 32

Heavy Quarkonium Suppression

  • M. Strickland

32 cartoon

  • In a high temperature quark-gluon plasma we

expect weaker color binding (Debye screening + asymptotic freedom)

  • E. V. Shuryak, Phys. Rept. 61, 71–158 (1980)
  • T. Matsui, and H. Satz, Phys. Lett. B178, 416 (1986)
  • F. Karsch, M. T. Mehr, and H. Satz, Z. Phys. C37, 617 (1988)
  • Also, high energy plasma particles which slam into

the bound states cause them to have shorter lifetimes à larger spectral widths

  • A. Bazavov and P. Petreczky, 1211.5638

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 33

CMS 2019 Data – 5.02 TeV Dimuon Spectra

The CMS (Compact Muon Solenoid) experiment has measured bottomonium spectra for both pp and Pb-Pb collisions. With this we can extract RAA experimentally.

  • M. Strickland

33

pp PbPb

Υ(1𝑡) Υ(2𝑡) Υ(3𝑡)

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SLIDE 34

New data at QM19

  • M. Strickland

34

  • New data from CMS and ALICE
  • Sufficient statistics to start extracting

production anisotropies

  • First data from ATLAS collaboration;

data explained well by KSU in-medium breakup model

  • LHCb is joining the effort (high mom res)
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SLIDE 35

Theory

  • M. Strickland

35

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SLIDE 36

Conceptually simple calculation

For in-medium suppression, given the population of quarkonia states at some t0, we can simply integrate the instantaneous decay/regeneration rate of the state G(t,x,y,h)

  • ver the QGP spatiotemporal evolution to obtain the survival probability.
  • M. Strickland

36

  • M. Martinez, R. Ryblewski, MS, arXiv:1204.1473

1 fm/c = 3 x 10-24 seconds

Pb-Pb @ 2.76 TeV T0 = 600 MeV t0 = 0.25 fm/c b = 7 fm

b = 7 fm

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SLIDE 37

Solve the 3d Schrödinger EQ with a complex-valued potential

37

  • M. Strickland

Fold together with the non-EQ spatiotemporal evolution to

  • btain the survival probability.

Obtain the real and imaginary parts of the binding energies for the U(1s), U(2s), U(3s), cb1, and cb2 as function of energy density and momentum-anisotropy.

Yager-Elorriaga and MS, 0901.1998; Margotta, MS, et al, 1101.4651

Summary of adiabatic the method

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SLIDE 38

The suppression factor

  • The suppression factor, RAA, is the ratio of the number of a

particular type of particle produced in a collision of two symmetric nuclei (AA) to the amount produced in a proton-proton (pp) collision scaled by the expected number of nucleon-nucleon collisions

RAA = NAA nbinary ⋅ N pp

Number of nucleon-nucleon collisions per nucleus collision Number produced in a proton-proton collision Number produced in a nucleus-nucleus collision

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SLIDE 39
  • =

|| < < < πη/ =

χ χ Υ() Υ() Υ()

State Suppression Factors, RAA

i

39

  • M. Strickland
  • B. Krouppa, R. Ryblewski, and MS, Phys. Rev. C 92, 061901(R)(2015).
  • Clear pattern of sequential

suppression

  • No sign of “thresholds”

(QGP thermometer is continuous!)

U(1s) cb(1p) cb(2p) U(2s) U(3s)

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SLIDE 40

Facing the experimental data... Adiabatic approximation

  • M. Strickland

40

slide-41
SLIDE 41
  • =

|| < < < Υ() Υ() Υ() Υ() πη/ = πη/ = πη/ =

Inclusive Bottomonium Suppression @ 2.76 TeV

41

  • B. Krouppa, R. Ryblewski, and MS, Phys. Rev. C 92, 061901(R) (2015).
  • ()
  • =

|| <

  • %

Υ() Υ() Υ() Υ() πη/ = πη/ = πη/ =

  • ||
  • =
  • %

< < Υ() Υ() Υ() Υ() Υ() πη/ = πη/ = πη/ =

  • Compare model to 2.76 TeV data

from CMS and ALICE

  • Reasonable agreement with CMS

data but not perfect

  • Disagreement with ALICE data in

rapidity range 2.5 < y < 4

  • Model slightly underpredicts

Y(2s) suppression

  • M. Strickland
slide-42
SLIDE 42
  • =

|| < < < Υ() Υ()

Υ() Υ() πη/ = πη/ = πη/ =

Inclusive Bottomonium Suppression @ 2.76 TeV

42

  • B. Krouppa, R. Ryblewski, and MS, Phys. Rev. C 92, 061901(R) (2015).
  • M. Strickland

Cold Nuclear Matter Effects

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SLIDE 43

Inclusive Bottomonium Suppression @ 5.02 TeV

43

  • B. Krouppa, R. Ryblewski, and MS 1704.02361
  • Model predictions compared to CMS data (left) and ALICE data (right)
  • Results below are as a function of Npart
  • M. Strickland
  • sNN = 5.02 TeV

2.5 < y < 4.0 0 < pT < 15 GeV

Υ() πη/ = πη/ = πη/ =

  • sNN = 5.02 TeV

|y| < 2.4 0 < pT < 30 GeV Υ(1S) Υ(2S)

Υ() Υ() πη/ = πη/ = πη/ =

  • CMS (left) covers central rapidity (|y| < 2.4) and ALICE (right)

covers forward rapidity (2.5 < |y| < 4)

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SLIDE 44

Bottomonium “flow” … or lack thereof

  • M. Strickland

44

4d flow tomography Quark Matter 2019

Cern Courier, Fall 2019

Bhadhuri, Alqahtani, Borghini, Jaiswal, and MS, 2007.03939

slide-45
SLIDE 45

Facing the experimental data... Real-time quantum evolution

  • M. Strickland

45

slide-46
SLIDE 46

NEW: Heavy Quarkonium Quantum Dynamics (HQQD)

  • M. Strickland

46

  • Sample bottomonium production points from binary collision overlap profile
  • Sample bottomonium initial momentum using pp experimental results
  • Calculate suppression for each of the states under consideration (1s, 2s, 3p,

3s, 3p) by solving 3D Schrödinger equation numerically for each trajectory.

  • Compute total number of produced states of each type
  • Then, take into account late-time feed down using a feed-down matrix

constructed from PDG branching

  • To obtain RAA, we then divide by the Nbin-scaled pp-production cross

sections.

  • To obtain vn, we compute <cos(nf)>
  • Errors reported are statistical à 1.2 million sampled trajectories
  • A. Islam and MS, forthcoming.
slide-47
SLIDE 47

HQQD RAA vs experimental data

  • M. Strickland

47

HQQD - Υ(1s) HQQD - Υ(2s) HQQD - Υ(3s)

ALICE - Y(1s) ATLAS - Y(1s) CMS - Y(1s) ATLAS - Y(2s) CMS - Y(2s)

100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 Npart RAA

5.02 TeV Pb-Pb ALICE: pT < 15 GeV and 2.5 < y < 4 ATLAS: pT < 15 GeV and |y| < 1.5 CMS: pT < 30 GeV and |y| < 2.4 HQQD - Υ(1s) HQQD - Υ(2s) HQQD - Υ(3s) ALICE - Y(1s) ATLAS - Y(1s) CMS - Y(1s) ATLAS - Y(2s) CMS - Y(2s)

5 10 15 20 25 30 0.0 0.2 0.4 0.6 0.8 1.0 pT RAA

5.02 TeV Pb-Pb CMS: 0-100% and |y| < 2.4 ALICE: 0-100% and 2.5 < y < 4 ATLAS: 0-80% and |y| < 1.5

  • A. Islam and MS, forthcoming.
  • A. Islam and MS, forthcoming.
slide-48
SLIDE 48

HQQD v2 predictions

  • M. Strickland

48

  • A. Islam and MS, forthcoming.

HQQD - Υ(1s) HQQD - Υ(2s) HQQD - Υ(3s)

10 20 30 40 50 60 70 80 90 100 0.00 0.02 0.04 0.06 0.08 Centrality (%) v2[Υ]

5.02 TeV Pb-Pb y=0 pT < 50 GeV

slide-49
SLIDE 49
  • M. Strickland

49

CMS 2020 ALICE 2019 HQQD

5 10 15

  • 0.05

0.00 0.05 0.10 pT [GeV] v2[Υ(1s)]

5.02 TeV Pb-Pb 5-60% Centrality CMS: |y| < 2.4 ALICE: 2.5 < y < 4

HQQD comparison to data

  • A. Islam and MS, forthcoming.
slide-50
SLIDE 50

HQQD comparison to data

  • M. Strickland

50

  • A. Islam and MS, forthcoming.

CMS 2020 ALICE 2019 HQQD

5 10 15

  • 0.05

0.00 0.05 0.10 pT [GeV] v2[Υ(1s)]

5.02 TeV Pb-Pb 5-60% Centrality CMS: |y| < 2.4 ALICE: 2.5 < y < 4

slide-51
SLIDE 51

QGP tomography

  • M. Strickland

51

  • A. Islam and MS, forthcoming.
slide-52
SLIDE 52

QGP tomography

  • M. Strickland

52

  • A. Islam and MS, forthcoming.
slide-53
SLIDE 53

Conclusions and Outlook

  • The suppression of bottomonium is a smoking gun for the creation
  • f the QGP
  • Initial state effects (aka cold nuclear matter effects) are not enough to

explain the experimental observations.

  • Complex screening model works reasonably well to describe the

suppression seen at LHC à QGP!

  • There is much work to do on this problem. One thing I did not discuss

today was “regeneration”. This occurs when the density of heavy (anti-)quarks becomes large, making it probable for a pair to recombine in the QGP. At very high temperatures/beam energies this effect is important for charm quarks, but still not so important for bottom quarks.

  • Showed forthcoming work on improving calculations to include full

real-time in-medium Schrödinger equation evolution (student A. Islam) à in-medium quantum regeneration

  • M. Strickland

53