Measurement of the mass of the D 0 meson Grauges, E.; Eigen, G.; Brown, D. N. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
10/2013, Letnik:
88, Številka:
7
Journal Article
The DIRC, a new type of ring-imaging Cherenkov detector that images internally reflected Cherenkov light, is being constructed as the main hadronic particle identification component of the BABAR ...detector at SLAC. The device makes use of 5 meter long fused silica (colloquially called quartz) bars, which serve both as the Cherenkov radiators and as light pipes for transmitting the light to an array of photo-multiplier tubes. This paper describes a program of research and development-aimed at determining whether bars that meet the stringent requirements of the DIRC can be obtained from commercial sources. The results of studies of bulk absorption of fused silica, surface finish, radiation damage and bulk inhomogeneities are discussed
The important role of chemoprophylaxis for the prevention of Pneumocystis carinii pneumonia (PCP) in human immunodeficiency virus type 1 (HIV)-infected patients is undisputed. The most cost-effective ...regimen, however, is unknown. We reviewed our experience at two hospitals in the New York City area in which low-dose, intermittent therapy with the combination of trimethoprim and sulfamethoxazole was used to prevent PCP in HIV-infected patients. During a total of 202 months of primary prophylaxis in 32 patients and 319 months of secondary prophylaxis in 35 patients, PCP was diagnosed only once. More than 80% of patients were receiving zidovudine concomitantly. Adverse reactions to trimethoprim-sulfamethoxazole occurred in 31% and 52% of those receiving primary or secondary prophylaxis, respectively. When those patients who were considered ineligible to receive trimethoprim-sulfamethoxazole prophylaxis (principally based on a prior adverse drug reaction) are also factored in, then approximately 50% of HIV-infected patients are candidates for long-term trimethoprim-sulfamethoxazole prophylaxis. The projected cost savings of this prophylaxis regimen, compared with those currently recommended by the US Public Health Service, are enormous.
A 74-year-old man from suburban New York City, who was hospitalized because of chest pain and fever, was diagnosed as having human granulocytic ehrlichiosis on the eighth hospital day. Although ...leukocyte and platelet counts were normal on admission, they fell to abnormally low values then normalized prior to specific therapy against the human granulocytic ehrlichiosis agent. Intracytoplasmic inclusions suggestive of Ehrlichia were observed in up to six percent of granulocytes, and the human granulocytic ehrlichiosis bacterium was cultured in an HL 60 human promyelocytic cell line. The patient improved dramatically within 24 hours of doxycycline treatment, after failing to improve on various beta lactam antimicrobial agents. He was discharged from the hospital 14 days after admission. Because human granulocytic ehrlichiosis was not diagnosed until his eight hospital day, clinical and laboratory parameters prior to specific treatment were available. This case illustrates the clinical and laboratory evolution of the infection with human granulocytic ehrlichiosis agent in humans.
The process e+e- --> p anti-p gamma is studied using 469 fb-1 of integrated luminosity collected with the BABAR detector at the PEP-II collider, at an e+e- center-of-mass energy of 10.6 GeV. From the ...analysis of the p anti-p invariant mass spectrum, the energy dependence of the cross section for e+e- --> p anti-p is measured from threshold to 4.5 GeV. The energy dependence of the ratio of electric and magnetic form factors, |G_E/G_M|, and the asymmetry in the proton angular distribution are measured for p anti-p masses below 3 GeV. We also measure the branching fractions for the decays J/psi --> p anti-p and psi(2S) --> p anti p.
Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new ...physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +- 0.058 +- 0.042 and R(D*) = 0.332 +- 0.024 +- 0.018, which exceed the Standard Model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, our results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. Kinematic distributions presented here exclude large portions of the more general type III two-Higgs-doublet model, but there are solutions within this model compatible with the results.