Jazz in British new wave cinema - An interview with Sir John Dankworth

Sir John Dankworth, the eminent English composer, conductor, bandleader and jazz musician has written in many genres, including composing over 20 film scores. Of these, Saturday Night and Sunday Morning (1960), The Criminal (1960), The Servant (1963) and Darling (1965) in particular, played a major role in bringing about a new sound in British film during the 1960s. This interview explores Sir John Dankworth's contribution to this innovative Film genre through his jazz-influenced musical scores

Stability of pentaquarks with a two- plus three-body chromoelectric interaction

We study the stability of pentaquarks within a schematic model based on SU(3) color symmetry, by taking into account algebraic arguments leading to a chromoelectric interaction containing two- and three-body parts. It has already been proven that such an interaction can influence the spectrum of ordinary baryons and the stability of tetraquarks and hexaquarks.Comment: 11 pages, 1 figure, it matches the published versio

X(5568) as a sudˉbˉs u \bar d \bar b tetraquark in a simple quark model

The $S$-wave eigenstates of tetraquarks of type $s u \bar d \bar b$ with J$^{P}$ = 0$^{+}$, 1$^{+}$ and 2$^{+}$ are studied within a simple quark model with chromomagnetic interaction and effective quark masses extracted from meson and baryon spectra. It is tempting to see if this spectrum can accommodate the new narrow structure X(5568), observed by the D\O~~Collaboration, but not confirmed by the LHCb Collaboration. If it exists, such a tetraquark is a system with four different flavors and its study can improve our understanding of multiquark systems. The presently calculated mass of X(5568) agrees quite well with the experimental value of he D\O~~Collaboration. Predictions are made for the spectrum of the charmed partner $s u \bar d \bar c$. However we are aware of the difficulty of extracting effective quark masses, from mesons and baryons, to be used in multiquark systems.Comment: 18 pages, 3 figures, it matches the published version in J.Phys.G43,105001. arXiv admin note: text overlap with arXiv:0906.248

Exploring the spectrum of the hidden charm strange pentaquark in an SU(4) flavor-spin model

We study the spectrum of the isoscalar pentaquark $udsc\overline{c}$, of either positive or negative parity, in a constituent quark model with linear confinement and a flavor-spin hyperfine interaction previously extended to SU(4) and used to describe the spectrum of the $uudc\overline{c}$ pentaquarks observed at LHCb in 2019. For positive parity we make a distinction between the case where one unit of angular momentum is located in the subsystem of four quarks and the case where the angular momentum is located in the relative motion between a ground state four-quark subsystem and the antiquark. The novelty is that we introduce the coupling between different flavor states, due to the breaking of exact SU(4)-flavor symmetry of the Hamiltonian model, both for positive and negative parity states. An important consequence is that the lowest state, located at 4404 MeV, has quantum numbers $J^P$ = $1/2^-$ while without coupling the lowest state has $J^P$ = $1/2^+$ or $3/2^+$.Comment: 26 pages, title slightly changed, other minor changes, it matches the published version. arXiv admin note: text overlap with arXiv:1902.0710

Positive parity pentaquarks in a Goldstone boson exchange model

We study the stability of the pentaquarks uuddQbar, uudsQbar and udssQbar (Q = c, b, or t) of positive parity in a constituent quark model based on Goldstone boson exchange interaction between quarks. The pentaquark parity is the antiquark parity times that of a quark excited to a p-shell. We show that the Goldstone boson exchange interaction favors these pentaquarks much more than the negative parity ones of the same flavour content but all quarks in the ground state. We find that the nonstrange pentaquarks are stable against strong decays.Comment: 13 pages, RevTe

Multiquark states in a Goldstone boson exchange model

We discuss the stability of multiquark systems containing heavy flavours. We show that the Goldstone boson exchange (GBE) model gives results at variance with the one-gluon-exchange (OGE) model, i.e. when the GBE model stabilizes a system the OGE model destabilizes it and vice-versa.Comment: 7 pages, RevTeX, Talk given at Joint ECT*/TJNAF workshop on N* physics and non-perturbative QCD, May 18-29, 1998, ECT*, Trento, Italy, to be published in Few-Body Systems Supp

Excited Baryons in the 1/N_c Expansion

We review results for the mass spectrum of orbitally excited baryons obtained in the $1/N_c$ expansion. We show the dependence of various contributions to the mass operator as a function of the excitation energy.Comment: 4 pages, 2 figures, based on a talk given by N. Matagne at the Workshop on the Physics of Excited Baryons (NSTAR 2005), Tallahassee, Florida, 12-15 October 200

Highly Excited Baryons in Large NcN_c QCD

We use the $1/N_c$ expansion of QCD to analyse the spectrum of positive parity resonances with strangeness $S = 0, -1, -2$ and -3 in the 2--3 GeV mass region, supposed to belong to the $[\textbf{56},4^+]$ multiplet. The mass operator is similar to that of $[\textbf{56},2^+]$, previously studied in the literature. The analysis of the latter is revisited. In the $[\textbf{56},4^+]$ multiplet we find that the spin-spin term brings the dominant contribution and that the spin-orbit term is entirely negligible in the hyperfine interaction, in agreement with constituent quark model results. More data are strongly desirable, especially in the strange sector in order to fully exploit the power of this approach. We discuss possibilities of extending the calculations to other excited baryons belonging to the N=2 or the N=4 band.Comment: 10 pages, Prepared for the Workshop "Three Days of Hadronics Physics", Joint Meeting Heidelberg-Liege-Paris-Rostock, December 16-18, 2004, Spa, Belgium, to be published in AIP Proceedings. One reference adde

Updated 1/Nc1/N_c expansion analysis of [56,2+][{\bf 56, 2^+}] and [70,ℓ+][{\bf 70, \ell^+}] baryon multiplets

The mass spectra of the $[{\bf 56, 2^+}]$ and $[{\bf 70, \ell+}]$ multiplets, both belonging to the $N$ = 2 band, is reviewed in the $1/N_c$ expansion method. Previous studies, separately made for each multiplet, are presently updated to the 2014 Particle Data Group. The mass formula including corrections up to $\mathcal{O}(1/N_c)$ and first order in SU(3) flavor symmetry breaking, has the same independent operator basis in both cases. A special emphasis is made on the role of the SU(3) symmetry breaking operators $B_i$ $(i = 1,2,3)$. This can allow for multiplet assignment of $\Lambda$ and $\Sigma$ hyperons, which generally is quite difficult to make. Tentative assignments of hyperons with two- and one-star resonances are made to the $[{\bf 70, \ell+}]$ multiplet. Another important aim is to find out whether or not a common value of the coefficient $c_1$ of the dominant operator in the mass formula, can well fit the present data in both multiplets. A negative answer, which is here the case, implies distinct Regge trajectories for symmetric and mixed symmetric states.Comment: 25 pages, to appear in Phys.Rev.