Related papers: Determining Pentaquark Quantum Numbers from Strong…
We report on searches in deep inelastic $ep$ scattering for narrow baryonic states decaying into $\Xi^-\pi^-, \Xi^-\pi^+, \KS p$ and their charge conjugates, at centre-of-mass energies of 300 and 318 GeV. No signal for a new narrow baryonic…
A narrow resonance peak was observed at 1.54 +/- 0.01 GeV as an exotic baryon with strangeness S = +1 in the gamma + n going to K^+ + K^- + n reaction on Carbon. The new state have a width smaller than 0.025 GeV and a Gaussian significance…
We investigate the pentaquark($P$) exotic baryons as soliton-antiflavored heavy mesons bound states in the limit of infinitely heavy meson mass. Our approach respects the chiral symmetry as well as the heavy quark symmetry. The results…
We briefly discuss the large Nc picture for excited baryons, present a new method for the calculation of matrix elements and illustrate it by computing the strong decays of heavy exotic states.
The Skyrme model is reconsidered from an effective theory point of view. From the most general chiral Lagrangian up to including terms of order $p^4$, $N_c$ and $\delta m^2$ ($\delta m\equiv m_s-m$), new interactions, which have never been…
In the SU(3) symmetry limit, semileptonic $D^+\to Sl^+\nu$ and $B^-\to Sl^-\bar\nu$ decays, with $S=a_0(980)$, $f_0(980)$ and $f_0(600)$, are found to obey different sum rules in the $\bar qq$ and the tetra-quark descriptions for scalar…
For tetraquarks of the form $T[(\bar{Q}q)(Q\bar{q})]$ we give sum rules for their decay coupling constants, taking into account the SU(3) symmetry breaking interactions to first order.
In some models, exotic baryons with strangeness and anticharm or antibeauty should exist and even be stable against strong decay. We consider the stability of such possible exotic baryons, which in the constituent quark picture are called…
QCD instantons are known to produce deeply bound diquarks which may be used as building blocks in the formation of multiquark states, in particular pentaquarks and dibaryons. We suggest a simple model in which the lowest scalar diquark (and…
Strangeness contents of baryons are calculated within rigid rotator model for arbitrary number of colors $N_c$. The problem of extrapolation to realistic value $N_c=3$ is noted, based on explicit calculations and comparison of rigid rotator…
Narrow Xi-pi+- and Xi-bar+pi+- resonances produced by quasi-real photons have been searched for by the COMPASS experiment at CERN. The study was stimulated by the recent observation of an exotic baryonic state decaying into Xi-pi-, at a…
The electromagnetic decays of the ground state baryon multiplets with one heavy quark are calculated using Heavy Hadron Chiral Perturbation Theory. The M1 and E2 amplitudes for S^{*}--> S gamma, S^{*} --> T gamma and S --> T gamma are…
The masses of exotic quantum-number $1^{-+}$ compact tetraquark states are calculated in a constituent quark model, where a Cornell-like potential is employed as the central potential, spin-spin and spin-orbit coupling derived from the…
Several experimental groups have reported evidence for baryons with flavor exotic quantum numbers that cannot be explained as $qqq$ bound states but require a minimum of five quarks -- $qqqq \bar q$. These pentaquark states include the…
Decay properties of multi-strangeness $\Xi$ and $\Omega$ baryon resonances are investigated within the constituent quark model by including relativistic corrections. The strong decay widths of various $\Xi$ and $\Omega$ resonances are…
Recent results from H1 and ZEUS on searches for exotic baryons in $ep$ collisions at HERA are reviewed. Evidence for the production of the strange pentaquark $\Theta^+$ and of a narrow anti-charmed baryon decaying to $D^{*-} p$ together…
If the number of colors Nc is taken large, baryons and their excitations can be considered in a mean-field approach. We argue that the mean field in baryons breaks spontaneously the spherical and SU(3) flavor symmetries, but retains the…
Following Rosner [hep-ph/0312269], we consider B-decay production channels for the exotic I=0 and $I=3/2$ pentaquarks that have been recently reported. We also discuss new search channels for isovector pentaquarks, such as the $\Theta^{*++}…
The exploration of exotic hadrons provides a crucial testing ground for quantum chromodynamics in its non-perturbative regime. In this work, we perform a systematic study of the two-body strong decay properties of single-charm molecular…
The recent developments in the search of exotic pentaquark hadrons are briefly reviewed. We then focus on investigating how the exotic pentaquark $\Theta(1540)$ baryon production can be identified in the $\gamma N \to K \bar{K} N$…