Here, the lifetime of the B$0\atop{S}$ meson is measured in the decay channel B$0\atop{S}$→J/ψπ+π- with 880 ≤ Mπ+π- ≤ 1080 MeV/c2, which is mainly a CP-odd state and dominated by the f0(980) ...resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the B$0\atop{S}$ meson is measured to be τ(B$0\atop{S}$) = 1.70 ± 0.14(stat) ± 0.05(syst) ps. Neglecting CP violation in B$0\atop{S}/$\bar{B}$0s mixing, the measurement can be translated into the width of the heavy mass eigenstate of the B$0\atop{S}$, ΓH = 0.59 ± 0.05(stat) ± 0.02(syst) ps-1.
The inclusive cross section of top quark-antiquark pairs produced in p (p) over bar collisions at root s = 1.96 TeV is measured in the lepton + jets and dilepton decay channels. The data sample ...corresponds to 9.7 fb(-1) of integrated luminosity recorded with the D0 detector during Run II of the Fermilab Tevatron Collider. Employing multivariate analysis techniques we measure the cross section in the two decay channels and we perform a combined cross section measurement. For a top quark mass of 172.5 GeV, we measure a combined inclusive top quark-antiquark pair production cross section of sigma(t<(t)over bar) = 7.26 +/- 0.13(stat)(-0.50)(+0.57) (syst) pb which is consistent with standard model predictions. We also perform a likelihood fit to the measured and predicted top quark mass dependence of the inclusive cross section, which yields a measurement of the pole mass of the top quark. The extracted value is m(t) = 172.8 +/- 1.1(theo)(-3.1)(+3.3) (exp) GeV.
We present a study of the inclusive production of the X(4140) state with the decay to the J/psi phi final state in hadronic collisions. Based on 10.4 fb(-1) of p (p) over bar collision data collected ...by the D0 experiment at the Fermilab Tevatron collider, we report the first evidence for the prompt production of an X(4140) state and find the fraction of X(4140) events originating from b hadrons to be f(b) = 0.39 +/- 0.07 (stat) +/- 0.10 (syst). The ratio of the nonprompt X(4140) production rate to the B-s(0) yield in the same channel is R = 0.19 +/- 0.05 (stat) +/- 0.07 (syst). The values of the mass M = 4152.5 +/- 1.7 (stat)(-5.4)(+/- 6.2)(syst) MeV and width Gamma = 16.3 +/- 5.6 (stat) +/- 11.4 (syst) MeV are consistent with previous measurements.
The fish and plant communities in a pond contaminated with polychlorinated biphenyls (PCBs) in East Tennessee, USA, were manipulated to reduce ecological and human-health risk associated with ...exposure to the chemical contaminants. We evaluated the success of the remedial action using a habitat valuation approach, as well as measuring PCB concentrations in fish. Risk reduction objectives included: alter the fish community to favor fish that do not resuspend, bioaccumulate, or biomagnify PCBs; stabilize contaminated sediments to improve water quality; and stabilize shoreline soils and enhance riparian habitat. Fish targeted for removal included gizzard shad, largemouth bass, and nonnative carp. Reduced PCB concentrations in fish have characterized the new bluegill-dominated community, although a weir-overtopping event led to the need for additional removals of gizzard shad and largemouth bass. Sunfish abundance is high, as was intended. Moreover, amphibian and waterbird diversities have increased in the years following biomanipulation, possibly owing to improvements in the riparian zone and increased structural (vegetation) complexity in both the aquatic and terrestrial environment. Thus, the remedial action has improved aspects of habitat value, and PCB concentrations in sunfish have dropped below the remediation level (risk-based target value) for this pond (1 µg/g in fish fillets or 2.3 µg/g in whole body fish).
We present the first search for CPT-violating effects in the mixing of B0s mesons using the full Run II data set with an integrated luminosity of 10.4 fb-1 of proton-antiproton collisions collected ...using the D0 detector at the Fermilab Tevatron Collider. We measure the CPT-violating asymmetry in the decay B0s → µ±D±s as a function of celestial direction and sidereal phase. We find no evidence for CPT-violating effects and place limits on the direction and magnitude of flavor-dependent CPTand Lorentz-invariance violating coupling coefficients. We find 95% confidence intervals of Δa⊥ < 1.2 × 10-12 GeV and (-0.8 < ΔaT - 0.396ΔaZ < 3.9) × 10-13 GeV.
•Examined effects of short-rotation pine for bioenergy on water quality in the field.•Few observations of saturated overland flow and little effect on stream water quality.•Nitrate concentrations ...increased in groundwater post-treatment to <2mgNL−1.•Forest BMPs can protect stream water quality in low-gradient southeast US watersheds.•Continued groundwater monitoring needed to examine long-term effects in these systems.
Growing interest in renewable and domestically produced energy motivates the evaluation of woody bioenergy feedstock production. In the southeastern U.S., woody feedstock plantations, primarily of loblolly pine (Pinus taeda), would be intensively managed over short rotations (10–12years) to achieve high yields. The primary differences in managing woody feedstocks for bioenergy production vs for pulp/sawtimber production include a higher frequency of pesticide and fertilizer applications, whole-tree removal, and greater ground disturbance (i.e., more bare ground during stand establishment and more frequent disturbance). While the effects of pulp/sawtimber production on water quality are well-studied, the effects of growing short-rotation loblolly pine on water quality and the efficacy of current forestry Best Management Practices (BMPs) have not been evaluated for this emerging management system. We used a watershed-scale experiment in a before-after, control-impact design to evaluate the effects of growing loblolly pine for bioenergy on water quality in the Upper Coastal Plain of the southeastern U.S. Intensive management for bioenergy production and implementation of current forestry BMPs occurred on ∼50% of two treatment watersheds, with one reference watershed in a minimally managed pine forest. Water quality metrics (nutrient and pesticide concentrations) were measured in stream water, groundwater, and interflow (i.e., shallow subsurface flow) for a two-year pre-treatment period, and for 3.5years post-treatment. After 3.5years, there was little change to stream water quality. We observed a few occurrences of saturated overland flow, but sediments and water dissipated within the streamside management zones in over 75% of these instances. Stream nutrient concentrations were low and temporal changes mainly reflected seasonal patterns in nitrogen cycling. Nitrate concentrations increased in groundwater post-treatment to <2mgNL−1, and these concentrations were below the U.S. drinking water standard (10mgNL−1). Applied pesticides were almost always below detection in streams and groundwater. Overall, these findings highlight that current forestry BMPs can protect stream water quality from intensive pine management for bioenergy in the first 3.5years. However, groundwater quality and transit times need to be considered in these low-gradient watersheds of the southeastern U.S. that are likely to become an important location for woody bioenergy feedstock production.
We present a measurement of the effective weak mixing angle parameter sin2θ$^{ℓ}_{eff}$ in $p$$\bar{p}$ → Z/γ* → μ+μ- events at a center-of-mass energy of 1.96 TeV, collected by the D0 detector at ...the Fermilab Tevatron Collider and corresponding to 8.6 fb-1 of integrated luminosity. The measured value of sin2θ$^{ℓ}_{eff}$ μμ = 0.23016 ± 0.00064 is further combined with the result from the D0 measurement in $p$$\bar{p}$ → Z/γ* → e+ e- events, resulting in sin2θ$^{ℓ}_{eff}$ comb = 0.23095 ± 0.00040. This combined result is the most precise measurement from a single experiment at a hadron collider and is the most precise determination using the coupling of the Z/γ* to light quarks.
We present the first measurement of the CP violating charge asymmetry in B±→μ±νμD0 decays using the full Run II integrated luminosity of 10.4 fb−1 in proton-antiproton collisions collected with the ...D0 detector at the Fermilab Tevatron Collider. We measure a difference in the yield of B− and B+ mesons in these decays by fitting the reconstructed invariant mass distributions. This results in an asymmetry of AμD0=−0.14±0.20%, which is consistent with standard model predictions.
We present a study of the X±(5568) using semileptonic decays of the Bs0 meson using the full run II integrated luminosity of 10.4 fb−1 in proton-antiproton collisions at a center of mass energy of ...1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. We report evidence for a narrow structure, X±(5568), in the decay sequence X±(5568)→Bs0π± where Bs0→μ∓Ds±X, Ds±→ϕπ± which is consistent with the previous measurement by the D0 Collaboration in the hadronic decay mode, X±(5568)→Bs0π± where Bs0→J/ψϕ. The mass and width of this state are measured using a combined fit of the hadronic and semileptonic data, yielding m=5566.9−3.1+3.2(stat)−1.2+0.6(syst) MeV/c2, Γ=18.6−6.1+7.9(stat)−3.8+3.5(syst) MeV/c2 with a significance of 6.7σ.
The fish and plant communities in a pond contaminated with polychlorinated biphenyls (PCBs) in East Tennessee, USA, were manipulated to reduce ecological and human-health risk associated with ...exposure to the chemical contaminants. We evaluated the success of the remedial action using a habitat valuation approach, as well as measuring PCB concentrations in fish. Risk reduction objectives included: alter the fish community to favor fish that do not resuspend, bioaccumulate, or biomagnify PCBs; stabilize contaminated sediments to improve water quality; and stabilize shoreline soils and enhance riparian habitat. Fish targeted for removal included gizzard shad, largemouth bass, and nonnative carp. Reduced PCB concentrations in fish have characterized the new bluegill-dominated community, although a weir-overtopping event led to the need for additional removals of gizzard shad and largemouth bass. Sunfish abundance is high, as was intended. Moreover, amphibian and waterbird diversities have increased in the years following biomanipulation, possibly owing to improvements in the riparian zone and increased structural (vegetation) complexity in both the aquatic and terrestrial environment. Thus, the remedial action has improved aspects of habitat value, and PCB concentrations in sunfish have dropped below the remediation level (risk-based target value) for this pond (1 µg/g in fish fillets or 2.3 µg/g in whole body fish).
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This paper addresses an uncommon but effective option for remediation of environmental contaminants in aquatic environments, biomanipulation. PCBs have important implications for human health and ecosystems. The paper combines analyses of PCB concentrations, habitat valuation, and water quality metrics, following biomanipulation of a pond. The 10-year study is longer than most published studies of environmental contaminants. The relevance is confirmed through funding from the US Department of Energy’s Environmental Management program, and federal and state regulatory agencies have shown interest in the findings. Biomanipulation is a less expensive and effective remediation alternative, compared to excavation of chemical contaminants.
This paper addresses an uncommon but effective option for remediation of environmental contaminants in aquatic environments, biomanipulation. PCBs have important implications for human health and ecosystems. The paper combines analyses of PCB concentrations, habitat valuation, and water quality metrics, following biomanipulation of a pond. The 10-year study is longer than most published studies of environmental contaminants. The relevance is confirmed through funding from the US Department of Energy’s Environmental Management program, and federal and state regulatory agencies have shown interest in the findings. Biomanipulation is a less expensive and effective remediation alternative, compared to excavation of chemical contaminants.
•An ecological manipulation in a contaminated pond reduced PCB concentrations in fish.•Habitat value metrics were measured over a 15-y period.•The pond transitioned from gizzard shad and largemouth bass dominance to sunfish.•PCB concentrations in bluegill decreased below risk-based targets.•Habitat metrics for most taxa are at least equal to those before biomanipulation.
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