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1.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36461983

ABSTRACT

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

2.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Article in English | MEDLINE | ID: mdl-35867467

ABSTRACT

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

3.
Phys Rev Lett ; 121(22): 221801, 2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30547637

ABSTRACT

The MiniBooNE experiment at Fermilab reports results from an analysis of ν_{e} appearance data from 12.84×10^{20} protons on target in neutrino mode, an increase of approximately a factor of 2 over previously reported results. A ν_{e} charged-current quasielastic event excess of 381.2±85.2 events (4.5σ) is observed in the energy range 200

4.
Phys Rev Lett ; 120(15): 152001, 2018 Apr 13.
Article in English | MEDLINE | ID: mdl-29756848

ABSTRACT

All lattice-QCD calculations of the hadronic-vacuum-polarization contribution to the muon's anomalous magnetic moment to date have been performed with degenerate up- and down-quark masses. Here we calculate directly the strong-isospin-breaking correction to a_{µ}^{HVP} for the first time with physical values of m_{u} and m_{d} and dynamical u, d, s, and c quarks, thereby removing this important source of systematic uncertainty. We obtain a relative shift to be applied to lattice-QCD results obtained with degenerate light-quark masses of δa_{µ}^{HVP,m_{u}≠m_{d}}=+1.5(7)%, in agreement with estimates from phenomenology.

5.
Phys Rev Lett ; 120(14): 141802, 2018 Apr 06.
Article in English | MEDLINE | ID: mdl-29694148

ABSTRACT

We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest (K^{+}→µ^{+}ν_{µ}) at the NuMI beamline absorber. These signal ν_{µ}-carbon events are distinguished from primarily pion decay in flight ν_{µ} and ν[over ¯]_{µ} backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9σ level. The muon kinetic energy, neutrino-nucleus energy transfer (ω=E_{ν}-E_{µ}), and total cross section for these events are extracted. This result is the first known-energy, weak-interaction-only probe of the nucleus to yield a measurement of ω using neutrinos, a quantity thus far only accessible through electron scattering.

6.
Phys Rev Lett ; 118(22): 221803, 2017 Jun 02.
Article in English | MEDLINE | ID: mdl-28621993

ABSTRACT

The MiniBooNE-DM Collaboration searched for vector-boson mediated production of dark matter using the Fermilab 8-GeV Booster proton beam in a dedicated run with 1.86×10^{20} protons delivered to a steel beam dump. The MiniBooNE detector, 490 m downstream, is sensitive to dark matter via elastic scattering with nucleons in the detector mineral oil. Analysis methods developed for previous MiniBooNE scattering results were employed, and several constraining data sets were simultaneously analyzed to minimize systematic errors from neutrino flux and interaction rates. No excess of events over background was observed, leading to a 90% confidence limit on the dark matter cross section parameter, Y=ε^{2}α_{D}(m_{χ}/m_{V})^{4}≲10^{-8}, for α_{D}=0.5 and for dark matter masses of 0.01

7.
Phys Rev Lett ; 115(15): 152002, 2015 Oct 09.
Article in English | MEDLINE | ID: mdl-26550717

ABSTRACT

The rare decay B→πℓ^{+}ℓ^{-} arises from b→d flavor-changing neutral currents and could be sensitive to physics beyond the standard model. Here, we present the first ab initio QCD calculation of the B→π tensor form factor f_{T}. Together with the vector and scalar form factors f_{+} and f_{0} from our companion work [J. A. Bailey et al., Phys. Rev. D 92, 014024 (2015)], these parametrize the hadronic contribution to B→π semileptonic decays in any extension of the standard model. We obtain the total branching ratio BR(B^{+}→π^{+}µ^{+}µ^{-})=20.4(2.1)×10^{-9} in the standard model, which is the most precise theoretical determination to date, and agrees with the recent measurement from the LHCb experiment [R. Aaij et al., J. High Energy Phys. 12 (2012) 125].


Subject(s)
Elementary Particles , Models, Theoretical , Nuclear Physics , Protons
8.
Phys Rev Lett ; 112(11): 112001, 2014 Mar 21.
Article in English | MEDLINE | ID: mdl-24702353

ABSTRACT

We calculate the kaon semileptonic form factor f+(0) from lattice QCD, working, for the first time, at the physical light-quark masses. We use gauge configurations generated by the MILC Collaboration with Nf = 2 + 1 + 1 flavors of sea quarks, which incorporate the effects of dynamical charm quarks as well as those of up, down, and strange. We employ data at three lattice spacings to extrapolate to the continuum limit. Our result, f+(0) = 0.9704(32), where the error is the total statistical plus systematic uncertainty added in quadrature, is the most precise determination to date. Combining our result with the latest experimental measurements of K semileptonic decays, one obtains the Cabibbo-Kobayashi-Maskawa matrix element |V(us)| = 0.22290(74)(52), where the first error is from f+(0) and the second one is from experiment. In the first-row test of Cabibbo-Kobayashi-Maskawa unitarity, the error stemming from |V(us)| is now comparable to that from |V(ud)|.

9.
Eur Phys J C Part Fields ; 74(9): 2890, 2014.
Article in English | MEDLINE | ID: mdl-25972762

ABSTRACT

We review lattice results related to pion, kaon, [Formula: see text]- and [Formula: see text]-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay-constant ratio [Formula: see text] of decay constants and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory and review the determination of the [Formula: see text] parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on [Formula: see text]- and [Formula: see text]-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant [Formula: see text].

10.
Phys Rev Lett ; 110(16): 161801, 2013 Apr 19.
Article in English | MEDLINE | ID: mdl-23679593

ABSTRACT

The MiniBooNE experiment at Fermilab reports results from an analysis of ν[over ¯](e) appearance data from 11.27×10(20) protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8σ) is observed in the energy range 200

11.
Phys Rev Lett ; 110(17): 172003, 2013 Apr 26.
Article in English | MEDLINE | ID: mdl-23679710

ABSTRACT

A calculation of the ratio of leptonic decay constants f(K+)/f(π+) makes possible a precise determination of the ratio of Cabibbo-Kobayashi-Maskawa (CKM) matrix elements |V(us)|/|V(ud)| in the standard model, and places a stringent constraint on the scale of new physics that would lead to deviations from unitarity in the first row of the CKM matrix. We compute f(K+)/f(π+) numerically in unquenched lattice QCD using gauge-field ensembles recently generated that include four flavors of dynamical quarks: up, down, strange, and charm. We analyze data at four lattice spacings a ≈ 0.06, 0.09, 0.12, and 0.15 fm with simulated pion masses down to the physical value 135 MeV. We obtain f(K+)/f(π+) = 1.1947(26)(37), where the errors are statistical and total systematic, respectively. This is our first physics result from our N(f) = 2+1+1 ensembles, and the first calculation of f(K+)/f(π+) from lattice-QCD simulations at the physical point. Our result is the most precise lattice-QCD determination of f(K+)/f(π+), with an error comparable to the current world average. When combined with experimental measurements of the leptonic branching fractions, it leads to a precise determination of |V(us)|/|V(ud)| = 0.2309(9)(4) where the errors are theoretical and experimental, respectively.

12.
Phys Rev Lett ; 109(7): 071802, 2012 Aug 17.
Article in English | MEDLINE | ID: mdl-23006357

ABSTRACT

The semileptonic decay channel B→Dτν is sensitive to the presence of a scalar current, such as that mediated by a charged-Higgs boson. Recently, the BABAR experiment reported the first observation of the exclusive semileptonic decay B→Dτ(-)ν, finding an approximately 2σ disagreement with the standard-model prediction for the ratio R(D)=BR(B→Dτν)/BR(B→Dℓν), where ℓ = e,µ. We compute this ratio of branching fractions using hadronic form factors computed in unquenched lattice QCD and obtain R(D)=0.316(12)(7), where the errors are statistical and total systematic, respectively. This result is the first standard-model calculation of R(D) from ab initio full QCD. Its error is smaller than that of previous estimates, primarily due to the reduced uncertainty in the scalar form factor f(0)(q(2)). Our determination of R(D) is approximately 1σ higher than previous estimates and, thus, reduces the tension with experiment. We also compute R(D) in models with electrically charged scalar exchange, such as the type-II two-Higgs-doublet model. Once again, our result is consistent with, but approximately 1σ higher than, previous estimates for phenomenologically relevant values of the scalar coupling in the type-II model. As a by-product of our calculation, we also present the standard-model prediction for the longitudinal-polarization ratio P(L)(D)=0.325(4)(3).

14.
Phys Rev Lett ; 105(18): 181801, 2010 Oct 29.
Article in English | MEDLINE | ID: mdl-21231096

ABSTRACT

The MiniBooNE experiment at Fermilab reports results from a search for ¯ν_{µ}→¯ν_{e} oscillations, using a data sample corresponding to 5.66×10²° protons on target. An excess of 20.9±14.0 events is observed in the energy range 475

15.
Phys Rev Lett ; 103(11): 111801, 2009 Sep 11.
Article in English | MEDLINE | ID: mdl-19792365

ABSTRACT

The MiniBooNE Collaboration reports initial results from a search for nu(mu)-->nu(e) oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10(20) protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200

16.
Urol Res ; 31(3): 212-7, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12719949

ABSTRACT

Unilateral ureteral obstruction (UUO) and hyperoxaluria (HOX) can lead to end-stage renal disease with tubulointerstitial fibrosis. We investigated the effects of enalapril (E), an ACE-inhibitor, on rat kidneys with either UUO or HOX. Sham-operated, UUO, HOX, UUO+HOX, UUO+E and HOX+E rats were killed 14 days after UUO and/or HOX was initiated. Rat kidney sections were histologically scored for tissue damage and monocyte/macrophage infiltration was demonstrated with ED1 antibody and measured by computer image analysis software. Serious glomerular and tubulointerstitial damage was found for UUO and HOX, consisting of glomerular basement membrane thickening, tubular dilatation/collapse, tubular basement membrane thickening and the infiltration of mononuclear leucocytes (mainly macrophages). For HOX, calcium oxalate crystals were visible. Neither the scored histological parameters nor monocyte/macrophage infiltration was significantly decreased when E-treated were compared with untreated groups. We conclude that E did not ameliorate the parameters scored in either UUO or HOX. This being contrary to findings by other research groups, we hypothesize that E may be effective only in short-term UUO/HOX, with transforming growth factor, TGF-beta1, formation becoming partly independent of Ang II in late-stage UUO/HOX, or other fibrogenic cytokines than TGF-beta1 becoming predominant.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Enalapril/pharmacology , Hyperoxaluria/pathology , Kidney/drug effects , Kidney/pathology , Ureteral Obstruction/pathology , Animals , Ectodysplasins , Hyperoxaluria/metabolism , Immunohistochemistry , Kidney/metabolism , Male , Membrane Proteins/metabolism , Rats , Rats, Wistar , Ureteral Obstruction/metabolism
17.
Am J Kidney Dis ; 38(2): 331-8, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11479159

ABSTRACT

Deposition of calcium oxalate (CaOx) crystals in the renal interstitium is common in humans with primary oxalosis and secondary hyperoxaluria, as well as in kidneys of rats with CaOx nephrolithiasis. In vivo, macrophages and multinucleated giant cells mostly encapsulate these crystals. To investigate whether macrophages are able to dispose of CaOx crystals after phagocytosis, we used a nontransformed macrophage cell line derived from mouse spleen progenitors. Cytokine assays showed that in response to crystal binding and phagocytosis, these macrophages release tumor necrosis factor-alpha. This release was evident at 8 hours, maximal at 24 hours, and decreased to control values after 48 hours of incubation with crystals. A very low but significant release of interleukin-6 into the culture medium was only noticed after 32 hours. Radiochemical experiments showed that these cells bind 38.8% of the CaOx crystals added. After 4 days, all internalized crystals had been dissolved and their molecular constituents released into the extracellular environment. Confocal laser scanning microscopy followed by morphometrical analyses confirmed these results. Long-term (survival) analyses showed that in the interval under study and at the crystal doses used, cell viability was not significantly affected. These findings support the view that properly functioning macrophages are able to remove CaOx deposits from the renal interstitium and that these cells produce inflammatory cytokines before crystal dissolution.


Subject(s)
Calcium Oxalate/metabolism , Interleukin-6/biosynthesis , Macrophages/metabolism , Tumor Necrosis Factor-alpha/biosynthesis , Animals , Cell Death , Cells, Cultured , Crystallization , Macrophages/cytology , Mice , Microscopy, Confocal , Phagocytosis
18.
J Org Chem ; 66(10): 3435-41, 2001 May 18.
Article in English | MEDLINE | ID: mdl-11348127

ABSTRACT

A low-temperature method for generating o-quinone methides is described which permits facile introduction of assorted R substituents onto the aryl ring system at low temperature. The method is useful for the efficient preparation of ortho-ring-alkylated phenols.


Subject(s)
Quinones/chemical synthesis , Alkylating Agents , Biological Factors/chemical synthesis , Combinatorial Chemistry Techniques , Phenols/chemical synthesis
19.
Org Lett ; 3(6): 905-8, 2001 Mar 22.
Article in English | MEDLINE | ID: mdl-11263912

ABSTRACT

A novel route to epoxysorbicillinol as well as dimers of sorbicillin is reported. The synthesis is-in principle-amenable to enantioselectivity. The key step is an oxidative dearomatization to produce a stable and highly malleable p-quinol intermediate, which undergoes a highly diastereoselective epoxidation.


Subject(s)
Cyclohexanones/chemical synthesis , Epoxy Compounds/chemical synthesis , Cyclohexanones/chemistry , Dimerization , Epoxy Compounds/chemistry , Indicators and Reagents , Models, Molecular , Molecular Conformation , Molecular Structure , Oxidation-Reduction , Stereoisomerism , Structure-Activity Relationship
20.
Am J Kidney Dis ; 36(3): 615-25, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10977795

ABSTRACT

Interstitial calcium oxalate (CaOx) crystals can be found in primary oxalosis and in secondary hyperoxaluria. In a rat model for nephrolithiasis, we investigated whether such crystals can be removed by the surrounding interstitial cells. CaOx crystals were induced by a crystal-inducing diet based on ethylene glycol (EG) and ammonium chloride (CID). Both lithogenic compounds were added to the drinking water. After 9 days, the animals received normal drinking water for 2 days. Using this CID, only the interstitial crystals are retained. Subsequently, half of the population remained on normal drinking water (normo-oxaluria), whereas the other half received a low dose of EG alone (chronic hyperoxaluria). The rats were killed at regular times thereafter. The results showed that the kidney-associated oxalate significantly declined during normo-oxaluria, but remained high during chronic hyperoxaluria. Interstitial cells positive for the leukocyte common antigen (CD45; which identifies all types of leukocytes), the ED1 antigen (which is specific for monocytes and macrophages), and the major histocompatibility class II antigen (MCHII), respectively, had increased in number, with minor differences between both rat populations. The cells around the interstitial crystals were mostly positive for ED1. Multinucleate giant cells were regularly observed. These cells were positive for CD45 and ED1 and sometimes also for MCHII. The crystals in these cells were moderately positive for acid phosphatase and carbonic anhydrase II. It is concluded that interstitial CaOx crystals can be removed under normo-oxaluric conditions and that, in all likelihood, macrophages and multinucleate giant cells are involved in that process.


Subject(s)
Calcium Oxalate/chemistry , Kidney Calculi/physiopathology , Leukocytes/physiology , Macrophages/physiology , Phagocytosis/physiology , Ammonium Chloride , Animals , Crystallization , Disease Models, Animal , Ethylene Glycol , Kidney Calculi/chemically induced , Kidney Calculi/chemistry , Leukocyte Common Antigens/metabolism , Leukocytes/immunology , Male , Rats , Rats, Wistar
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