Download or read book Global Analysis Of The Negative Parity Non Strange Baryons In The 1 N sub C Expansion written by and published by . This book was released on 2014 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A global study of the negative parity non-strange baryon observables is performed in the framework of the 1/N{sub c} expansion. Masses, partial decay widths and photo-couplings are simultaneously analyzed. A main objective is to determine the composition of the spin 1/2 and 3/2 nucleon states, which come in pairs and involve two mixing angles which can be determined and tested for consistency by the mentioned observables. The issue of the assignment of those nucleon states to the broken SU(4) X O(3) mixed-symmetry multiplet is studied in detail, with the conclusion that the assignment made in the old studies based on the non-relativistic quark model is the preferred one. In addition, the analysis involves an update of the input data with respect to previous works.
Download or read book Decays of Negative Parity Non strange Baryons in the 1 Nc Expansion written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The decays of non-strange negative parity baryons via the emission of single [pi] and [eta] mesons are analyzed in the framework of the 1/N{sub c} expansion. A basis of spin-flavor operators is established to that order, and with this basis the different partial wave decay amplitudes are obtained. The unknown effective coefficients are determined by fitting to the S- and D-wave partial widths as provided by the PDG. A full set of relations between widths that result at the leading order, i.e. order N{sub c0}, is given and tested with the data. The rather large errors of the input partial widths, that result from the often discrepant results for the resonance parameters from different analyses of the data, lead to a rather good fit at the leading order N{sub c0}. The next to leading order fit fails for that reason to pin down with satisfactory accuracy the effective sub leading effective constants.
Download or read book Negative Parity 70 plet Baryon Masses in the 1 written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The masses of the negative parity SU(6) 70-plet baryons are analyzed in the 1/N{sub c} expansion to order 1/N{sub c} and to first order in SU(3) breaking. At this level of precision there are twenty predictions. Among them there are the well known Gell-Mann Okubo and equal spacing relations, and four new relations involving SU(3) breaking splittings in different SU(3) multiplets. Although the breaking of SU(6) symmetry occurs at zeroth order in 1/N{sub c}, it turns out to be small. The dominant source of the breaking is the hyperfine interaction which is of order 1/N{sub c}. The spin-orbit interaction, of zeroth order in 1/N{sub c}, is entirely fixed by the splitting between the singlet states A(1405) and A(1520), and the spin-orbit puzzle is resolved by the presence of other zeroth order operators involving flavor exchange.
Download or read book The IVth International Conference on Quarks and Nuclear Physics written by Antonio Dobado and published by Springer Science & Business Media. This book was released on 2008-11-07 with total page 615 pages. Available in PDF, EPUB and Kindle. Book excerpt: The QNP series of international conferences on Quarks and Nuclear Physics is by now a well established and highly respected forum where the most recent developments in the field are discussed and communicated. QNP 2006 is the forth edition of this biennial meeting. Selected and refereed original contributions of QNP 2006 have been published in The European Physical Journal A - Hadrons and Nuclei (EPJ A), while the present proceedings book, in addition to reprinting the articles published in EPJ A, further includes all other contributions selected and accepted by the organizing committee for publication and archiving.
Download or read book Negative Parity Baryon Decays in the 1 Nc Expansion written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The $1/N_c$ expansion of QCD provides a useful framework for phenomenological studies of both ground state and excited baryons. Here, we focus on its application to the excited baryon strong decays via emission of single pseudoscalar meson. The S- and D-wave decay amplitudes of the negative parity baryons in the $[70,1^-]$ of $SU(6)$ are analyzed to subleading order in $1/N_c$ and to first order in SU(3) symmetry breaking. In particular, the SU(3) symmetry breaking is studied in detail through SU(3) breaking decay operators and state mixing.
Download or read book Decays of Non strange Positive Parity Excited Baryons in the 1 written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The decays of non-strange positive parity baryons via emission of a pseudo-scalar meson are studied in the framework of the 1/Nc expansion to order 1/Nc. In particular, the pionic decays of the l=0 Roper baryons and of the l=2 baryons in the mass interval 1680-1950 MeV are analyzed using the available partial decay widths. Decay widths by emission of an eta meson are shown to be suppressed by a factor 1/Nc2 with respect to the pionic ones.
Download or read book Photoproduction of Positive Parity Baryons in the 1 written by and published by . This book was released on 2006 with total page 62002 pages. Available in PDF, EPUB and Kindle. Book excerpt: We analyze the photoproduction helicity amplitudes for non-strange positive parity excited baryons in the context of the 1/N{sub c} expansion of QCD. Our results strongly suggest that, although one-body transition operators provide the dominant contributions, two-body transition operators are definitely required in order to get good fits to the presently known empirical amplitudes. The significance of this result for quark model calculations is briefly discussed.
Download or read book Analysis of Negative Parity Baryon Photoproduction Helicity Amplitudes in the 1 written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We study the photoproduction helicity amplitudes of negative parity baryons in the context of the 1/Nc expansion of QCD. A complete analysis to next-to-leading order is carried out. The results show sub-leading effects to be within the magnitude expected from the $1/N_c$ power counting. They also show significant deviations from the quark model, in particular the need for 2-body effects.
Download or read book Analysis of 56 plet Positive Parity Baryon Decays in the 1 Nc Expansion written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The partial decay widths of positive parity baryons belonging to 56-plets of SU(6) are analyzed in the framework of the 1/Nc expansion. The channels considered are those with emission of a single pion, K or K-bar mesons, and the analysis is carried out to subleading order in 1/Nc and to first order in SU(3) symmetry breaking. The results for the multiplet [56,0+], to which the Roper resonance belongs, indicate a poor description at leading order, requiring large next to leading order corrections. For the multiplet [56,2+], the P-wave decays in the non-strange sector are well described at leading order and important SU(3) breaking corrections are necessary to describe transitions involving strangeness, on the other hand, the F-wave decays require the next to leading order corrections, which turn out to be however of natural magnitude.
Download or read book Strange Decays of Nonstrange Baryons written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The strong decays of excited nonstrange baryons into the final states [Lambda]K, [Sigma]K, and for the first time into [Lambda](1405)K, [Lambda](1520)K, [Sigma](1385)K, [Lambda]K{sup *}, and [Sigma]K{sup *}, are examined in a relativized quark pair creation model. The wave functions and parameters of the model are fixed by previous calculations of N[pi] and N[pi][pi], etc., decays. The results show that it should be possible to discover several new negative parity excited baryons and confirm the discovery of several others by analyzing these final states in kaon production experiments. They also establish clear predictions for the relative strengths of certain states to decay to [Lambda](1405)K and [Lambda](1520)K, which can be tested to determine if a three-quark model of the [Lambda](1405)K is valid. The authors results compare favorably with the results of partial wave analyses of the limited existing data for the [Lambda]K and [Sigma]K channels. They do not find large [Sigma]K decay amplitudes for a substantial group of predicted and weakly established negative-parity states, in contrast to the only previous work to consider decays of these states into the strange final states [Lambda]K and [Sigma]K.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1970 with total page 998 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Baryons in the 1 Nc Expansion written by Jose L. Goity and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A brief overview of the 1/N{sub c} expansion in the baryon sector is given, with emphasis on recent analyses of masses and decays of excited baryons.
Download or read book Lepton and Baryon Number Violation in Particle Physics Astrophysics and Cosmology written by H. V. Klapdor-Kleingrothaus and published by CRC Press. This book was released on 1999-01-01 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bringing together leading researchers from particle physics, astrophysics, and cosmology, Lepton and Baryon Number Violation in Particle Physics, Astrophysics and Cosmology presents reviews of current theoretical ideas, experimental results, and future perspectives in this topical field. The book covers areas related to baryon number (B) and lepton number (L) violation in particle physics, nuclear physics, rare decays, and cosmology. The main topics include B and L violation and grand unified theories; B and L violation in the early universe, cosmology, and astrophysics; Lepton family number violation; and B and L violation and collider physics.
Download or read book Large N sub C Limit of Spin flavor Breaking in Excited Baryon Levels written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Spin-flavor symmetry breaking in the levels of excited Baryons are studied to leading order in the 1/N{sub c} expansion. This breaking occurs at zeroth order. For non-strange Baryons with a single quark excited, it is shown that to first order of perturbation theory the breaking is given by one 1-body operator (spin-orbit), and three 2-body operators, all involving the orbital angular momentum of the excited quark. Higher-body operators can be reduced to that set of operators. As illustration, p-wave Baryons are briefly discussed.
Download or read book Baryons in the 1 written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A brief overview of the 1/N{sub c} expansion in the baryon sector is given, with emphasis on recent analyses of masses and decays of excited baryons.
Download or read book The Non compact Group SU 2 2 and Electromagnetic Form Factors of Baryons written by Tsu Yao and published by . This book was released on 1969 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Double Charm and Charm Strange Baryons InElectron Positron Annihilations written by and published by . This book was released on 2007 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation I describe a study of double-charm and charm-strange baryons based on data collected with the BABAR Detector at the Stanford Linear Accelerator Center. In this study I search for new baryons and make precise measurements of their properties and decay modes. I seek to verify and expand upon double-charm and charm-strange baryon observations made by other experiments. The BABAR Detector is used to measure subatomic particles that are produced at the PEP-II storage rings. I analyze approximately 300 million e+e- → c{bar c} events in a search for the production of double-charm baryons. I search for the double-charm baryons?{sub cc} (containing the quarks ccd) and?{sup ++}{sub cc} (ccu) in decays to?+{sub c}K−?+ and?+{sub c}K−?+?+, respectively. No statistically significant signals for their production are found, and upper limits on their production are determined. Statistically significant signals for excited charm-strange baryons are observed with my analysis of approximately 500 million e+e- → c{bar c} events. The charged charm-strange baryons?{sub c}(2970)+,?{sub c}(3055)+,?{sub c}(3123)+ are found in decays to?+{sub c}K−?+, the same decay mode used in the?+{sub cc} search. The neutral charm-strange baryon?{sub c}(3077)° is observed in decays to?+{sub c}K?−. I also search for excited charm-strange baryon decays to?+{sub c}K8,?+{sub c}K−,?+{sub c}K8?−?+, and?+{sub c}K−?−?+. No significant charm-strange baryon signals a f h these decay modes. For each excited charm-strange baryon state that I observe, I measure its mass, natural width (lifetime), and production rate. The properties of these excited charm-strange baryons and their decay modes provide constraints for phenomenological models of quark interactions through quantum chromodynamics. My discovery of the two new charm-strange baryons?{sub c}(3055)+ and?{sub c}(3123)+ influences our theoretical understanding of charm-strange baryon states.
