Nuclear Theory·nucl-th

Thursday·July 2, 2015

6 papers—3 primary·3 cross-listed

04
[Submitted on 30 Jun 2015] (cross-list from hep-ph)
Bottomonium Mesons and Strategies for Their Observation
Stephen Godfrey🇨🇦 · Kenneth Moats (Carleton University)🇨🇦
The $B$ -factories and Large Hadron Collider experiments have demonstrated the ability to observe and measure the properties of bottomonium mesons. In order to discover missing states it is useful to know their properties to develop a successful search strategy. To this end we calculate the masses and decay properties of excited bottomonium states. We use the relativized quark model to calculate the masses and wavefunctions and the $^{3} P_{0}$ quark-pair creation model to calculate decay widths to open bottom. We also summarize results for radiative transitions, annihilation decays, hadronic transitions and production cross sections which are used to develop strategies to find these states. We find that the $b b ˉ$ system has a rich spectroscopy that we expect to be substantially extended by the LHC and $e^{+} e^{-}$ experiments in the near future. Some of the most promising possibilities at the LHC are observing the $χ_{b (1, 2)} (3 P)$ , $χ_{b (1, 2)} (4 P)$ and $η_{b} (3 S)$ states in $γ μ^{+} μ^{-}$ final states that proceed via radiative transitions through $Υ (n S)$ intermediate states and $1^{3} D_{J}$ and $2^{3} D_{J}$ into $γ γ μ^{+} μ^{-}$ final states proceeding via $1^{3} P_{J} \to 1^{3} S_{1}$ and $2^{3} P_{J} \to 2^{3} S_{1}$ intermediate states respectively. Some of the most interesting possibilities in $e^{+} e^{-}$ collisions are studying the $1^{3} D_{J}$ states via $4 γ$ cascades starting with the $Υ (3 S)$ and the $3^{3} P_{J}$ states in $γ γ μ^{+} μ^{-}$ final states starting with the $Υ (4 S)$ and proceeding via $Υ (n S)$ intermediate states. Completing the bottomonium spectrum is an important validation of lattice QCD calculations and a test of our understanding of bottomonium states in the context of the quark model.
Comments:
38 pages, 1 figure, 36 tables, Changes: A few minor word changes. Corrected phase error in equation A12 which effected strong decays to 1P_1 and 1P_1' final states. All instances have been corrected with no effect on our conclusions
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1507.00024 [pdf]
PRD(2015)·183 citations
05
[Submitted on 1 Jul 2015] (cross-list from hep-ph)
Neutrinoless Double Beta Decay
Heinrich Päs🇩🇪 · Werner Rodejohann🇩🇪
We review the potential to probe new physics with neutrinoless double beta decay $(A, Z) \to (A, Z + 2) + 2 e^{-}$ . Both the standard long-range light neutrino mechanism as well as short-range mechanisms mediated by heavy particles are discussed. We also stress aspects of the connection to lepton number violation at colliders and the implications for baryogenesis.
Comments:
Review prepared for the NJP focus issue on "Neutrino Physics". 23 pages, 10 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1507.00170 [pdf]
New J.Phys.(2015)·153 citations
06
[Submitted on 1 Jul 2015] (cross-list from hep-ph)
Configuration Mixing of Quark States in Baryons
B. Saghai🇫🇷 · Z. Li🇺🇸
Mixing angles are used to describe the $S U (6) \otimes O (3)$ symmetry breaking in $[70, 1^{-}]$ multiplet in the sector of the lowest mass nucleon resonances, which are investigated extensively in constituent quark models for baryon spectroscopy. The transition amplitudes for the meson photoproduction off nucleon can also be expressed in terms of the mixing angles to take into account the configuration mixing. Those amplitudes are derived as a function of the mixing angles between $∣ N^{2} P_{M} J^{-} ⟩$ and $∣ N^{4} P_{M} J^{-} ⟩$ states, with $J$ =1/2 and 3/2, for the processes $γ p \to η p, K^{+} Λ, K^{+} Σ^{\circ}, K^{\circ} Σ^{+}$ . The present status of our knowledge on the mixing angles between $S_{11} (1535)$ and $S_{11} (1650)$ ( $θ_{S}$ ), as well as between $D_{13} (1520)$ and $D_{13} (1700)$ ( $θ_{D}$ ) is reported. Since these resonances play very important role in the threshold region for both $η$ and kaon production mechanisms, they are expected to provide crucial tests of different quark models for the baryon spectroscopy.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1507.00236 [pdf]
Few Body Syst.(2010)·5 citations

Affiliations

first authorsco-authorsvia INSPIRE

Bottomonium Mesons and Strategies for Their Observation

Neutrinoless Double Beta Decay

Configuration Mixing of Quark States in Baryons

Affiliations