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Mannque Rho

Publications and source records attributed to Mannque Rho.

At least 127 records · Page 7Linked to original sources
arXiv2006

Late Hadronization and Matter Formed at RHIC: Vector Manifestation, Brown-Rho Scaling and Hadronic Freedom

Recent developments in our description of RHIC and related heavy-ion phenomena in terms of hidden local symmetry theories are reviewed with a focus on the novel nearly massless states in the vicinity of -- both below and above -- the chiral restoration temperature T_c. We present complementary and intuitive ways to understand both Harada-Yamawaki's vector manifestation structure and Brown-Rho scaling -- which are closely related -- in terms of "melting" of soft glues observed in lattice calculations and join the massless modes that arise in the vector manifestation (in the chiral limit) just below T_c to tightly bound massless states above T_c. This phenomenon may be interpreted in terms of the Beg-Shei theorem. It is suggested that hidden local symmetry theories arise naturally in holographic dual QCD from string theory, and a clear understanding of what really happens near the critical point could come from a deeper understanding of the dual bulk theory. Other matters discussed are the relation between Brown-Rho scaling and Landau Fermi-liquid fixed point parameters at the equilibrium density, its implications for "low-mass dileptons" produced in heavy-ion collisions, the reconstruction of vector mesons in peripheral collisions, the pion velocity in the vicinity of the chiral transition point, kaon condensation viewed from the VM fixed point, nuclear physics with Brown-Rho scaling, and the generic feature of dropping masses at the RGE fixed points in generalized hidden local symmetry theories.

nucl-th↗
arXiv2005

NA60 and BR Scaling in Terms of the Vector Manifestation: A Model Approach

It is pointed out that the comparison between the recent NA60 dimuon data and the so-called "Brown-Rho (BR) scaling" as presented at QM2005 is $not$ founded on a correct interpretation of the prediction of BR scaling as formulated in 1991 and modernized recently and hence the conclusion drawn by both the experimental and theoretical speakers that "BR scaling is ruled out by NA60" is erroneous and should be disregarded. We use a simplified model description of how the vector manifestation of hidden local symmetry theory enters into the dilepton production, relegating more rigorous discussions to a follow-up paper.

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arXiv2005

The Ideal Liquid Discovered by RHIC, Infrared Slavery Above and Hadronic Freedom Below $T_c$

We construct the nature of the matter found in RHIC when its temperature has dropped down close to, and below, $T_c$. Just above $T_c$ it is composed of extremely strongly bound quark-antiquark pairs forming chirally restored mesons of the quantum numbers of the $π, S, ρ$ and $a_1$ with very small size and zero energy and just below $T_c$, it is composed of mesons of the same quantum numbers with zero mass. We invoke infrared slavery for the former and the vector manifestation (VM) of hidden local symmetry for the latter. As the temperature drops below $T_c$, the strongly bound quark-antiquark pairs are ejected into what is basically a region of "hadronic freedom" in which the interactions are zero. Experimental evidences for this are seen in the STAR data.

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arXiv2005

Pion Velocity near the Chiral Phase Transition Point in the Vector Manifestation

We study the pion velocity near the critical temperature $T_c$ of chiral symmetry restoration in QCD. Using chiral perturbation theory based on hidden local symmetry (HLS) as an effective field theory, where the chiral symmetry restoration is realized as the vector manifestation (VM), we show that the pion velocity for $T \to T_c$ is close to the speed of light, $v_π(T) = 0.83 - 0.99$ which is at variance with the sigma model result which predicts $v_π(T_c) = 0$. Our prediction on $v_π(T_c)$ is compared with the value extracted from the recent RHIC data.

hep-ph↗
arXiv2005

Relation of Strangeness Nuggets to Strangeness Condensation and the Maximum Mass of Neutron Stars

Combining the recent experimental indications of density dependence in the pion decay constant $f_π^\star$ and the $ω$ meson mass $m_ω^\star$ and the discovery of $S^0 (3115)$ and other "strange nuggets" with the vector manifestation of chiral symmetry in hidden local symmetry proposed by Harada and Yamawaki, we show that the mechanism responsible for dense strangeness nuggets can be related to that responsible for kaon condensation in neutron-star matter. We suggest that this relation assures kaon condensation at a density $\sim$ three times nuclear matter density which supports the Brown-Bethe scenario for the $M_{\rm NS}^{max} \simeq 1.5\msun$. This low $M_{\rm NS}^{\rm max}\sim 1.5\msun$ has major consequences in astrophysics, especially for the merging rate of compact stellar objects.

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arXiv2005

Pentaquarks, Skyrmions and the Vector Manifestation of Chiral Symmetry

The structure of the pentaquark baryon $Θ^+$ is discussed in terms of a $K^+$-skyrmion binding where the skyrmion arises as a soliton in hidden local symmetry approach to low-energy hadronic physics which may be considered as a holographic dual to QCD. The "vector manifestation" of chiral symmetry encoded in the effective theory Wilsonian-matched to QCD is proposed to play an important role in the binding. Among the options available for understanding the pentaquark structure is the intriguing possibility that the $Θ^+$ is a Feshbach resonance generated by the solitonic matter that drives the Wess-Zumino term that in the presence of $K^\star$ acts like a magnetic field.

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arXiv2004

Kaon-Soliton Bound State Approach to the Pentaquark States

We show that in hidden local symmetry theory with the vector manifestation (VM), a K^+ can be bound to skyrmion to give the Theta^+ pentaquark with spin 1/2 and even parity which is consistent with large N_c counting. The vector meson K^* subject to the VM in the chiral limit plays an essential role in inducing the binding.

hep-ph↗
arXiv2004

Unified Approach to Dense Matter

We apply the Skyrme model to dense hadronic matter, which provides a unified approach to high density, valid in the large Nc limit. In our picture, dense hadronic matter is described by the classical soliton configuration with minimum energy for the given baryon number density. By incorporating the meson fluctuations on such ground state we obtain an effective Lagrangian for meson dynamics in a dense medium. Our starting point has been the Skyrme model defined in terms of pions, thereafter we have extended and improved the model by incorporating other degrees of freedom such as dilaton, kaons and vector mesons.

hep-ph↗
arXiv2004

Chiral Doubling of Heavy-Light Hadrons and the Vector Manifestation of Hidden Local Symmetry

Starting with a hidden local symmetry Lagrangian at the vector manifestation (VM) fixed point that incorporates heavy-quark symmetry and matching the bare theory to QCD, we calculate the splitting of chiral doublers of heavy-light mesons proposed by Nowak, Rho and Zahed, and Bardeen and Hill. We show, in the three-flavor chiral limit, that the splitting is directly proportional to the light-quark condensate <\bar{q}q> and comes out to be \sim (1/3) m_N where m_N is the nucleon mass, implying that the splitting vanishes in the chiral limit at the chiral restoration point -- temperature T_c, density n_c or number of flavors N_F^c. The result turns out to be surprisingly simple with the vector (ρ) meson playing the crucial role in quantum corrections, pointing to the relevance of the VM to QCD in the way chiral symmetry is manifested in hadronic matter. We also make predictions on the hadronic decay processes of the excited heavy (charm) -light mesons \tilde{D}.

hep-ph↗
arXiv2004

The \bar q q Bound States and Instanton Molecule at T >~ T_c

The main objective of this work is to explore the evolution in the structure of the quark-anti-quark bound states in going down in the chirally restored phase from the so-called "zero binding points" $T_{zb}$ to the full (unquenched) QCD critical temperature $T_c$ at which the Nambu-Goldstone and Wigner-Weyl modes meet. In doing this, we adopt the idea recently introduced by Shuryak and Zahed for charmed $\bar c c$, light-quark $\bar q q$ mesons $π, σ, ρ, A_1$ and gluons that at $T_{zb}$, the quark-anti-quark scattering length goes through $\infty$ at which conformal invariance is restored, thereby transforming the matter into a near perfect fluid behaving hydrodynamically, as found at RHIC. We show that the binding of these states is accomplished by the combination of (i) the color Coulomb interaction, (ii) the relativistic effects, and (iii) the interaction induced by the instanton-anti-instanton molecules. The spin-spin forces turned out to be small. While near $T_{zb}$ all mesons are large-size nonrelativistic objects bound by Coulomb attraction, near $T_c$ they get much more tightly bound, with many-body collective interactions becoming important and making the $σ$ and $π$ masses approach zero (in the chiral limit). The wave function at the origin grows strongly with binding, and the near-local four-Fermi interactions induced by the instanton molecules play an increasingly more important role as the temperature moves downward toward $T_c$.

hep-ph↗
arXiv2004

The Pion Velocity in Dense Skyrmion Matter

We have developed a field theory formalism to calculate $in$-$medium$ properties of hadrons within a unified approach that exploits a single Lagrangian to describe simultaneously both matter background and meson fluctuations. In this paper we discuss the consequences on physical observables of a possible phase transition of hadronic matter taking place in the chiral limit. We pay special attention to the pion velocity $v_π$, which controls, through a dispersion relation, the pion propagation in the hadronic medium. The $v_π$ is defined in terms of parameters related to the matrix element in matter of the axial-vector current, namely, the in-medium pion decay constants, $f_t$ and $f_s$. Both of the pion decay constants change dramatically with density and even vanish in the chiral limit when chiral symmetry is restored, but the pion velocity does not go to zero, decreasing at most 10% over the whole density range studied. A possible pseudogap structure is indicated.

hep-ph↗
arXiv2004

A new state of matter at high temperature as "sticky molasses"

The main objective of this work is to explore the evolution in the structure of the quark-antiquark bound states in going down in the chirally restored phase from the so-called "zero binding points" $T_{zb}$ to the QCD critical temperature $T_c$ at which the Nambu-Goldstone and Wigner-Weyl modes meet. In doing this, we adopt the idea recently introduced by Shuryak and Zahed for charmed $\bar c c$, light-quark $\bar q q$ mesons $π, σ, ρ, A_1$ and gluons that at $T_{zb}$, the quark-antiquark scattering length goes through $\infty$ at which conformal invariance is restored, thereby transforming the matter into a near perfect fluid behaving hydrodynamically, as found at RHIC. We name this new state of matter as "sticky molasses". We show that the binding of these states is accomplished by the combination of (i) the color Coulomb interaction, (ii) the relativistic effects, and (iii) the interaction induced by the instanton-anti-instanton molecules. The spin-spin forces turned out to be small. While near $T_{zb}$ all mesons are large-size nonrelativistic objects bound by Coulomb attraction, near $T_c$ they get much more tightly bound, with many-body collective interactions becoming important and making the $σ$ and $π$ masses approach zero (in the chiral limit). The wave function at the origin grows strongly with binding, and the near-local four-Fermi interactions induced by the instanton molecules play an increasingly more important role as the temperature moves downward toward $T_c$.

hep-ph↗
arXiv2004

Chiral Symmetry of Heavy-Light-Quark Hadrons in Hot/Dense Matter

The recent discoveries by the BaBar and CLEO II collaborations on the splitting between $D_s$ and ${\tilde D}_s$ which exhibited surprises in the structure of heavy-light-quark systems are connected -- via the Harada-Yamawaki "vector manifestation" of hidden local symmetry -- to chiral symmetry restoration expected to take place at some critical temperature $T_c$ in heavy-ion collisions or at some critical density $n_c$ in the deep interior of compact stars, the main theme of this symposium. This unexpected connection exemplifies the diversity of astro-hadronic phenomena discussed in this meeting.

hep-ph↗
arXiv2004

Topological Structure of Dense Hadronic Matter

We present a summary of work done on dense hadronic matter, based on the Skyrme model, which provides a unified approach to high density, valid in the large $N_c$ limit. In our picture, dense hadronic matter is described by the {\em classical} soliton configuration with minimum energy for the given baryon number density. By incorporating the meson fluctuations on such ground state we obtain an effective Lagrangian for meson dynamics in a dense medium. Our starting point has been the Skyrme model defined in terms of pions, thereafter we have extended and improved the model by incorporating other degrees of freedom such as dilaton, kaons and vector mesons.

hep-ph↗
arXiv2003

The Pion Velocity at Chiral Restoration and the Vector Manifestation

We study the effects of Lorentz non-invariance on the physical pion velocity at the critical temperature $T_c$ in an effective theory of hidden local symmetry (HLS) with the "vector manifestation" fixed point. We match at a "matching scale" $Λ_M$ the axial-vector current correlator in the HLS with the one in the operator product expansion for QCD, and present the matching condition to determine the bare pion velocity. We find that the physical pion velocity, which is found to be one at $T=T_c$ when starting from the Lorentz invariant bare HLS, remains close to one with the Lorentz non-invariance, $v_π(T_c) = 0.83 - 0.99$. This result is quite similar to the pion velocity in dense matter.

hep-ph↗
arXiv2003

Vector Mesons and Dence Skyrmion Matter

In our continuing effort to understand hadronic matter at high density, we have developed a unified field theoretic formalism for dense skyrmion matter using a single Lagrangian to describe simultaneously both matter and meson fluctuations and studied in-medium properties of hadrons. Dropping the quartic Skyrme term, we incorporate into our previous Lagrangian the vector mesons rho and omega in a form which is consistent with the symmetries of QCD. The results that we have obtained, reported here, expose a hitherto unsuspected puzzle associated with the role the omega meson plays at short distance. Since the omega meson couples to baryon density, it leads to a pseudo-gap scenario for the chiral symmetry phase transition, which is at variance with standard scenario of QCD at the phase transition. We find that in the presence of the omega mesons, the scale-anomaly dilaton field is prevented from developing a vanishing vacuum expectation value at the chiral restoration, as a consequence of which the in-medium pion decay constant does not vanish. This seems to indicate that the omega degree of freedom obstructs the vector manifestation which is considered to be a generic feature of effective field theories matched to QCD.

hep-ph↗
arXiv2003

Chiral Doubling of Heavy-Light Hadrons: BaBar 2317 MeV and CLEO 2463 MeV Discoveries

We point out that the very recent discoveries of BaBar (2317) and CLEO II (2460) are consistent with the general pattern of spontaneous breaking of chiral symmetry in hadrons built of heavy and light quarks, as originally suggested by us in 1992, and independently by Bardeen and Hill in 1993. The splitting between the chiral doublers follows from a mixing between the light constituent quark mass and the velocity of the heavy quark, and vanishes for a zero constituent quark mass. The general strictures of spontaneous chiral symmetry breaking constrain the axial charges in the chiral multiplet, and yield a mass splitting between the chiral doublers of about 345 MeV when the pion coupling to the doublers is half its coupling to a free quark. The chiral corrections are small. This phenomenon is generic and extends to all heavy-light hadrons. We predict the mass splitting for the chiral doublers of the excited mesons (D1,D2). We suggest that the heavy-light doubling can be used to address issues of chiral symmetry restoration in dense and/or hot hadronic matter. In particular, the relative splitting between D and D* mesons and their chiral partners decreases in matter, with consequences on charmonium evolution at RHIC.

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