Related papers: Experimental Review on Pentaquarks
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…
The strange-anticharmed Pentaquark is a uud(cbar)s or udd(cbar)s five-quark baryon that is expected to be either a narrow resonance, or possibly even stable against strong decay. We describe this hyperon here; its structure, binding energy…
Although the Theta has been listed as a three star resonance in the 2004 PDG,its existence is still not completely established. Now it is still of interest to see what QCD has to say on the subject, In this paper we review briefly the…
Since LEPS collaboration reported the first evidence of $\Theta^+$ pentaquark in early 2003, eleven other experimental groups have confirmed this exotic state while many other groups didn't see any signal. If this state is further…
The strange-anticharmed Pentaquark is a $uud\bar{c}s$ or $udd\bar{c}s$ five-quark baryon that is expected to be either a narrow resonance, or possibly even stable against strong and electromagnetic decay. We describe this hyperon here, its…
Using the experimental data on pentaquarks with a hidden charm, new upper limits on the intrinsic charm in the proton are obtained, possible shapes of heavy quark distributions inside the proton are discussed.
Tetraquarks are studied with an approximation which reduces the in- ternal degrees of freedom of the system, using both finite differences and scattering theory. The existence of bound states and resonances is inspected and the masses and…
The experimental status of the pentaquark searches is briefly reviewed. Recent null results by the CLAS collaboration are commented, and new strong evidence of a very narrow Theta+ resonance by the DIANA collaboration is presented. On the…
Is there a theory or good experimental evidence? Bj's question: Pentaquark is created by $e^+e^-$. $2q + q \to$ Baryon $; ~ ~ ~ 2q + \bar q \to $ Triquark$ ; ~ ~ ~ 2q + $Triquark $ \to $Pentaquark Does it live long onough to be observable?…
In this paper I review the history and geography of the pentaquark searches and discuss the current situation surrounding these searches performed at different facilities around the world. The possibility of the existence of multiquark…
We review the new results on the heavy flavor baryons and on the pentaquarks.
A brief survey is presented of selected recent results in hadron spectroscopy and related theoretical studies. This includes the pentaquarks and hadrons containing one or two charmed quarks or antiquarks.
In this contribution, we discuss the electromagnetic couplings of pentaquark states with hidden charm. This work is motivated by recent experiments at CERN by the LHCb Collaboraton and current experiments at JLab to confirm the existence of…
Possible existence of a molecular-type heavy-flavored strange pentaquark is considered. No narrow state of such a type is shown to exist.
We comment on the recent claim for the experimental observation of neutrinoless double-beta decay. We discuss several limitations in the analysis provided in that paper and conclude that there is no basis for the presented claim.
The contradiction between evidence for and against the existence of the Theta+ pentaquark might be resolved if it only appears as a result of a particular production mechanism which is present in some experiments and absent in others. We…
We review lattice calculations of pentaquarks and discuss issues pertaining to interpolation fields, distinguishing the signal of pentaquarks from those of the KN scattering states, chiral symmetry, and ghost state contaminations.
We review the experimental evidence on firstly, strangeness production as a signature for the QCD phase transition and secondly, pentaquarks, the latest and most exotic manifestations of strangeness in hadrons.
Current evidence does not favor the existence of the \thplus pentaquark, which was reported by several groups in the years after 2002. The question naturally arises: how could many groups could have seen fluctuations in their data at the…
Non-strange and strange pentaquaks with hidden charm are considered as diquark-diquark-antiquark composite systems. Spin and isospin content of such exotic states is discussed and masses are evaluated.