Hadron production by quark

coalescence in heavy ion collisions

Sep. 17th, 2020

Seminar at Yonsei University

via zoom

Sungtae Cho

Kangwon National University

Outline

− Introduction

− Charmed hadrons in heavy ion collisions

− Hadron production by quark coalescence

− Transverse momentum distribution of

charmed hadrons

− Conclusion

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− Relativistic heavy ion collisions

U. W. Heinz, J. Phys. Conf. Ser. 455, 012044 (2013)3

Introduction

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− Charmed hadrons, SU(4)

1) Charmonium states :

ηc, J/ψ, χc, ψ’

2) Charmed baryons

and mesons : D, D*, Ds, Ds*, Λc(2286), Λc(2595),

A. De Rujula, H. Georgi, And S. Glashaw, Λc(2625), Σc(2455), Σc(2520),

Phys. Rev. D 12, 147 (1975) Ξc(2470), Ξc(2578), Ξc(2645),

Ωc(2695), Ωc(2770)

3) Doubly and triply

charmed hadrons,

exotic hadrons : Ξcc, Ξ*cc,

Ωcc, Ω*cc, Ωccc,, Tcc, X(3872)

R. A. Briceno, H.-W. Lin, and D. R. Bolton,

Phys. Rev. D 86 094504 (2012)

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− Charmed hadrons, SU(4)

1) Charmonium states :

ηc, J/ψ, χc, ψ’

2) Charmed baryons

and mesons : D, D*, Ds, Ds*, Λc(2286), Λc(2595),

A. De Rujula, H. Georgi, And S. Glashaw, Λc(2625), Σc(2455), Σc(2520),

Phys. Rev. D 12, 147 (1975) Ξc(2470), Ξc(2578), Ξc(2645),

Ωc(2695), Ωc(2770)

3) Doubly and triply

charmed hadrons,

exotic hadrons : Ξcc, Ξ*cc,

Ωcc, Ω*cc, Ωccc,, Tcc, X(3872)

R. A. Briceno, H.-W. Lin, and D. R. Bolton,

Phys. Rev. D 86 094504 (2012)

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− Recent measurements of a doubly

charmed baryon in 2017

− Tcc (ccqq) mesons

S. Cho et al. (EXHIC Collaboration), Phys. Rev. C 84, 064910 (2011)

S. Cho et al. (EXHIC Collaboration), Prog. Part. Nucl. Phys. 95, 279 (2017)

J. Hong, S. Cho, T. Song, and S-H. Lee, Phys. Rev. C 98, 014913 (2018)

− X(3872) mesons

J. Beringer et al. (PDG), Phys. Rev. D86,

010001 (2012)

S.K. Choi et al. [Belle Collaboration], Phys. Rev. Lett. 90, 242001 (2003)

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− Internal structure of X(3872) mesons

1) Possible structures of X(3872) mesons, 3 independent relative

coordinates

D. M. Brink and Fl. Stancu,

Phys. Rev. D 49, 4665 (1994)

2) The relative coordinates and momentum of X(3872) mesons

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L. Musa (CERN), Strangeness in Quark Matter 2019, Bari, June 10-15

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Yen-jie Lee (MIT), Quark Matter 2019, Wuhan, November 4-9

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− Charmonium states

T. Matsui and H. Satz, Phys. Lett. B 178 416 (1986)

1) J/ψ suppression and Debye screening

At T>Tc color charges are Debye screened in QGP, and the Debye

screening prevents the formation of the bound states

2) The different charmonium states melt sequentially as a function

of their binding strength;

the most loosely bound state disappears first, the ground state last

H. Satz, J. Phys. G.

32, R25 (2006)

10

Charmed hadrons

in heavy ion collisions

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− Regeneration of J/ψ mesons

1) The nuclear modification

factor of J/ψ mesons

B. Abelev et al, (ALICE Collaboration),

Phys. Rev. Lett. 109, 072301

2) Elliptic flows, v2 of the J/ψ

E. Abbas et al, Phys. Rev. Lett. 111, 162301 (2013)

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− Charmonium states in heavy ion collisions

1) The nuclear modification factor ratio between the J/ψ and the ψ’

V. Khachatryan et al, Phys. Rev. Lett. 113, 262301 (2014)

M. Aaboud et al, Eur. Phys. J. C 78, 762 (2018)

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− Yields of hadrons in the coalescence model

V. Greco, C. M. Ko, and P. Levai, Phys. Rev. C 68, 034904 (2003)

R. J. Freis. B. Muller, C. Nonaka, and S. Bass, Phys. Rev. C 68, 044902 (2003)

1) The Wigner function, the coalescence probability function

2) A Lorentz-invariant phase space integration of a space-like

hyper-surface constraints the number of particles in the system

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Hadron production

by quark coalescence

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3) The internal structure of hadrons produced is considered

s-wave

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d-wave

4) Yields in coalescence model

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− Hadron production by recombination

: Transverse momentum distributions of hadron yields

1) The puzzle in antiproton/pion ratio

V. Greco, C. M. Ko, and P. Levai, Phys. Rev. Lett. 90, 202302 (2003)

R. J. Freis. B. Muller, C. Nonaka, and S. Bass, Phys. Rev. Lett. 90, 202303 (2003)

originated from a competition

between two particle

production mechanisms

: A fragmentation dominates

at large transverse momenta

and a coalescence prevails

at lower transverse momenta

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2) The transverse momentum spectra

and

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− Charmonia production by recombination

S. Cho, Phys. Rev. C 91, 054914 (2015)

1) Charmonia yield in the quark coalescence model

Transverse momentum distribution of charmonium states

2) Gaussian Wigner functions for different charmonium states

17

Transverse momentum

distributions of charmed hadrons

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− Multi-charmed hadron production

1) Yields in the statistical hadronization model

A. Andronic, P. Braun-Munzinger, K. Redlich and J. Stachel, Nucl. Phys. A 904-905, 535c (2013)

J. Stachel, A. Andronic, P. Braun-Munzinger, and K. Redlich, J. Phys. Conf. Ser. 509, 012019 (2014)

S. Cho et al. [ExHIC Collaboration], Prog. Part. Nucl. Phys. 95, 279 (2017)

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− Production of multi-charmed hadrons by recombination

S. Cho and S. H. Lee, Phys. Rev. C 101, 024902 (2020)

1) Multi-charmed hadron Yields in the coalescence model

2) Transverse momentum distributions

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3) Transverse momentum distributions of charm and light

quarks

S. Plumari, V. Minissale, S. K. Das, G. Coci and V. Greco, Eur. Phys. J. C 78:348 (2017)

Y. Oh, C. M. Ko, S.-H. Lee, and S. Yasui, Phys. Rev. C 79 044905 (2009)

S. Cho et al. (EXHIC Collaboration), Prog. Part. Nucl. Phys. 95, 279 (2017)

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4) Transverse momentum distributions of D0 mesons

J. Adam et al. [STAR Collaboration], Phys. Rev. C 99, no. 3, 034908 (2019).

J. Adam et al. [ALICE Collaboration], JHEP 1603, 081 (2016).

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5) Transverse momentum distributions

of multi-charmed hadrons

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6) Transverse momentum distribution ratios

a) Baryon/baryon (ccc/ccq, ccc/ccs, ccq/ccs, and ccq/cqq)

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b) Baryon/baryon (ccc/cqq, or ccs/cqq)

c) Meson/baryon (ccqq/ccq, or cc/ccq)

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d) Baryon/meson (ccc/cc)

− Comparison with results from the statistical

hadronization model

A. Andronic, P. Braun-Munzinger, M. K. Kohler, K. Redlich and J. Stachel, Phys. Lett. B 797, 134836 (2019).

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− Dependence of the transverse momentum

distribution on internal relative coordinates

1) The Wigner function of the (3872) meson

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Conclusion

− Hadron production by quark coalescence

in heavy ion collisions

1) Heavy ion collision experiments provide better chances to study

production of multi-charm hadrons as well as exotic hadrons

2) Transverse momentum distributions of charmonium states are

affected by their intrinsic wave function distributions

3) The transverse momentum distribution is also dependent on the

internal structure of the hadron

4) Transverse momentum distribution ratios between multi-charm

hadrons and X(3872) mesons, or other combinations between

heavy quark hadrons reflect the distribution of momentum

among constituent quarks 28Sep. 17th, 2020

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Thank you for your attention!

29Sep. 17th, 2020 Seminar at Yonsei University

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