Mass spectra of doubly heavy Omega_QQ' baryons

We evaluate the masses of baryons composed of two heavy quarks and a strange quark with account for spin-dependent splittings in the framework of potential model with the KKO potential motivated by QCD with a three-loop beta-function for the effective charge consistent with both the perturbative limit at short distances and linear confinement term at long distances between the quarks. The factorization of dynamics is supposed and explored in the nonrelativistic Schroedinger equation for the motion in the system of two heavy quarks constituting the doubly heavy diquark and the strange quark interaction with the diquark. The limits of approach, its justification and uncertainties are discussed. Excited quasistable states are classified by the quantum numbers of heavy diquark composed by the heavy quarks of the same flavor.Comment: 14 pages, revtex4-file, 3 eps-figures, 5 tables, typos correcte

Dual fast-cycling superconducting synchrotron at Fermilab and a possible path to the future of high energy particle physics

We briefly outline shorter and longer term physics motivation for constructing a dual, fast-cycling superconducting synchrotron accelerator (DSFMR - Dual Super-Ferric Main Ring) in the Tevatron tunnel at Fermilab. We discuss using this accelerator as a high-intensity dual neutrino beam source for the long-baseline neutrino oscillation search experiments, and also as a fast, dual pre-injector accelerator for the VLHC (Very Large Hadron Collider)

Biotic and abiotic retention, recycling and remineralization of metals in the ocean

Trace metals shape both the biogeochemical functioning and biological structure of oceanic provinces. Trace metal biogeochemistry has primarily focused on modes of external supply of metals from aeolian, hydrothermal, sedimentary and other sources. However, metals also undergo internal transformations such as abiotic and biotic retention, recycling and remineralization. The role of these internal transformations in metal biogeochemical cycling is now coming into focus. First, the retention of metals by biota in the surface ocean for days, weeks or months depends on taxon-specific metal requirements of phytoplankton, and on their ultimate fate: that is, viral lysis, senescence, grazing and/or export to depth. Rapid recycling of metals in the surface ocean can extend seasonal productivity by maintaining higher levels of metal bioavailability compared to the influence of external metal input alone. As metal-containing organic particles are exported from the surface ocean, different metals exhibit distinct patterns of remineralization with depth. These patterns are mediated by a wide range of physicochemical and microbial processes such as the ability of particles to sorb metals, and are influenced by the mineral and organic characteristics of sinking particles. We conclude that internal metal transformations play an essential role in controlling metal bioavailability, phytoplankton distributions and the subsurface resupply of metals

Doubly heavy baryons Omega_QQ' vs. Xi_QQ' in sum rules of NRQCD

In the framework of two-point sum rules of NRQCD, the masses and couplings of doubly heavy baryons to the corresponding quark currents are evaluated with account of coulomb-like corrections in the system of doubly heavy diquark as well as the contribution of nonperturbative terms determined by the quark, gluon, mixed condensates and the product of gluon and quark condensates. The introduction of nonzero light quark mass destroys the factorization of baryon and diquark correlators even at the perturbative level and provides the better convergency of sum rules. We estimate the difference M_Omega - M_Xi = 100+/- 10 MeV. The ratio of baryonic constants |Z_Omega|^2/|Z_Xi|^2 is equal to 1.3+/-0.2 indicating the violation of SU(3) flavor symmetry for the doubly heavy baryons.Comment: 18 pages, ReVTeX file, 7 eps-figures, references adde

Combination of searches for WW, WZ, and ZZ resonances in pp collisions at s=8 TeV with the ATLAS detector

The ATLAS experiment at the CERN Large Hadron Collider has performed searches for new, heavy bosons decaying to WW, WZ and ZZ final states in multiple decay channels using 20.3 fb-1 of pp collision data at s=8 TeV. In the current study, the results of these searches are combined to provide a more stringent test of models predicting heavy resonances with couplings to vector bosons. Direct searches for a charged diboson resonance decaying to WZ in the ℓνℓ'ℓ' (ℓ=μ, e), ℓℓqq-, ℓνqq- and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WZ bosons are compared with predictions of an extended gauge model with a heavy W' boson. In addition, direct searches for a neutral diboson resonance decaying to WW and ZZ in the ℓℓqq-, ℓνqq-, and fully hadronic final states are combined and upper limits on the rate of production times branching ratio to the WW and ZZ bosons are compared with predictions for a heavy, spin-2 graviton in an extended Randall-Sundrum model where the Standard Model fields are allowed to propagate in the bulk of the extra dimension

The metabolic basis of whole-organism RNA and phosphorus content

Understanding the storage, flux, and turnover of nutrients in organisms is important for quantifying contributions of biota to biogeochemical cycles. Here we present a model that predicts the storage of phosphorus-rich RNA and whole-body phosphorus content in eukaryotes based on the mass- and temperature-dependence of ATP production in mitochondria. Data from a broad assortment of eukaryotes support the model's two main predictions. First, whole-body RNA concentration is proportional to mitochondrial density and consequently scales with body mass to the -1/4 power. Second, whole-body phosphorus content declines with increasing body mass in eukaryotic unicells but approaches a relatively constant value in large multicellular animals because the fraction of phosphorus in RNA decreases relative to the fraction in other pools. Extension of the model shows that differences in the flux of RNA-associated phosphorus are due to the size dependencies of metabolic rate and RNA concentration. Thus, the model explicitly links two biological currencies at the individual level: energy in the form of ATP and materials in the form of phosphorus, both of which are critical to the functioning of ecosystems. The model provides a framework for linking attributes of individuals to the storage and flux of phosphorus in ecosystems