Instantons and Scalar Multiquark States: From Small to Large Nc
نویسنده
چکیده
X iv :h ep -p h/ 03 09 15 8 v1 14 S ep 2 00 3 Instantons and Scalar Multiquark States: From Small to Large Nc T. Schäfer Department of Physics, North Carolina State University, Raleigh, NC 17695 Riken-BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 Abstract We study scalar (q̄q) and (q̄q)2 correlation functions in the instanton liquid model. We show that the instanton liquid supports a light scalar-isoscalar (sigma) meson, and that this state is strongly coupled to both (q̄q) and (q̄q)2. The scalar-isovector a0 meson, on the other hand, is heavy. We also show that these properties are specific to QCD with three colors. In the large Nc limit the scalar-isoscalar meson is not light, and it is mainly coupled to (q̄q).
منابع مشابه
X iv : h ep - p h / 01 01 06 1 v 1 8 J an 2 00 1 Do Instantons and Strings Cluster when the Number of Colors is Large ?
We consider the Nc → ∞ limit of QCD using a toy model in which instantons exchange color-singlet scalar fields which do not selfinteract. Our main observation is that collective attraction leads the formation of large clusters containing O(Nc) nonperturbative objects. We further show that this clustering of instantons is limited due to a non-trivial repulsion inherent in the ADHM multi-instanto...
متن کاملToward dynamical understanding of the diquarks, pentaquarks and dibaryons
QCD instantons are known to produce deeply bound diquarks. We study whether it may be used as building blocks in the formation of multiquark states, in particular pentaquarks and dibaryons. A simple model is presented in which the lowest scalar diquark (and possibly the tensor one) can be treated as an independent “body”, with the same color and (approximately) the same mass as a constituent (a...
متن کاملar X iv : h ep - p h / 01 01 06 1 v 2 8 O ct 2 00 1 Do Instantons and Strings Cluster when the Number of Colors is Large ?
We consider the Nc → ∞ limit of QCD using a toy model in which instantons exchange color-singlet scalar fields which do not selfinteract. Our main observation is that collective attraction leads the formation of large clusters containing O(Nc) nonperturbative objects. We further show that this clustering of instantons is limited due to a non-trivial repulsion inherent in the ADHM multi-instanto...
متن کاملInstantons in the Higgs Phase
When instantons are put into the Higgs phase, vortices are attached to instantons. We construct such composite solitons as 1/4 BPS states in five-dimensional supersymmetric U(NC) gauge theory with NF(≥ NC) fundamental hypermultiplets. We solve the hypermultiplet BPS equation and show that all 1/4 BPS solutions are generated by an NC × NF matrix which is holomorphic in two complex variables, ass...
متن کاملHeavy Baryons and Multiquark Exotics in the Large N C Limit * Typeset Using Revt E X
In the large Nc limit, one can describe normal heavy baryons Qqq and heavy pentaquarks Q̄qqqq as bound states of heavy mesons to chiral (anti)solitons. In this picture, the strong and electromagnetic decay parameters of these hadrons can be calculated from those of the constituent heavy mesons and light baryons, while the weak decay form factors can be evaluated analytically. Typeset using REVTE...
متن کامل