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H S Budd

Publications and source records attributed to H S Budd.

79 records · Page 5Linked to original sources
PubMed2001

First measurement of the ratio B(t --> Wb)/B(t --> Wq) and associated limit on the Cabibbo-Kobayashi-Maskawa element /V(tb)/.

We present the first measurement of the ratio of branching fractions R identical withB(t-->Wb)/B(t-->Wq) from p_p collisions at sqrt[s] = 1.8 TeV. The data set corresponds to 109 pb(-1) of data recorded by the Collider Detector at Fermilab during the 1992-95 Tevatron run. We measure R = 0.94(+0.31)(-0.24)(stat+syst) or R>0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element /V(tb)/ under the assumption of three generations and unitarity.

Journal Article↗
PubMed2000

Measurement of J/psi and psi(2S) polarization in pp collisions at sqrt[s] = 1.8 TeV.

We have measured the polarization of J/psi and psi(2S) mesons produced in pp collisions at sqrt[s] = 1.8 TeV, using data collected at the Collider Detector at Fermilab during 1992-1995. The polarization of promptly produced J/psi [psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4 [5.5]<P(T)<20 GeV/c and |y|<0.6. For P(T) greater than or approximately equal 12 GeV/c we do not observe significant polarization in the prompt component.

Journal Article↗
PubMed2000

Search for scalar top and scalar bottom quarks in pp collisions at square root s=1.8 TeV.

We have searched for direct pair production of scalar top and scalar bottom quarks in 88 pb-1 of pp collisions at sqrt[s]=1.8 TeV with the CDF detector. We looked for events with a pair of heavy flavor jets and missing energy, consistent with scalar top (bottom) quark decays to a charm (bottom) quark and a neutralino. The numbers of events that pass our selections show no significant deviation from standard model expectations. We compare our results to the next-to-leading order scalar quark production cross sections to exclude regions in scalar quark-neutralino mass parameter space.

Journal Article↗
PubMed2000

Search for a W' boson via the decay mode W'-->munumu in 1.8 TeV pp collisions.

We report the results of a search for a W' boson produced in pp collisions at a center-of-mass energy of 1.8 TeV using a 107 pb-1 data sample recorded by the Collider Detector at Fermilab. We consider the decay channel W'-->&munumu and search for anomalous production of high transverse mass munumu lepton pairs. We observe no excess of events above background and set limits on the rate of W' boson production and decay relative to standard model W boson production and decay using a fit of the transverse mass distribution observed. If we assume standard model strength couplings of the W' boson to quark and lepton pairs, we exclude a W' boson with invariant mass less than 660 GeV/c2 at 95% confidence level.

Journal Article↗
PubMed1984

Somatic cell hybridization of human tumor samples.

Human intraspecific hybrids were formed between tumor cells isolated from both primary and metastatic tumors and a tissue culture adapted cell line, D98OR, a HeLa derivative which is thioguanine and ouabain resistant. Five different tumor types in all were attempted: renal cell carcinoma, colon adenocarcinoma, melanoma, chrondrosarcoma, and hepatocarcinoma. The tumor tissue was either (1) immediately dissociated and fused, or (2) frozen and later thawed, dissociated, and fused. Two different PEG concentrations were used. The results reported here demonstrate that: (1) hybrid tumor cell lines can be made from several types of cancer, (2) unfrozen tumor tissue fused with D98OR by exposure to 50% PEG appears optimal, (3) chromosome loss, as determined by flow cytometry studies of hybrid DNA content, is minimal, and (4) hybrids have characteristics consistent with derivation from tumor cells rather than derivation from the nonmalignant cells of a tumor.

Cell Fusion↗
PubMed1982

Antitumor immunity induced by hybrid murine tumor cells: requirements for optimal immunization.

Hybrid tumor cells have been evaluated for their ability to induce specific antitumor immunity in inbred female C3H/He mice challenged with the syngeneic BA tumor. Hybrid cells were produced by fusion of BA cells with a BALB/c renal adenocarcinoma, which is hypoxanthine phosphoribosyl transferase-deficient and grows well in culture. Corynebacterium parvum was evaluated as an adjuvant for BA and hybrid cells. The BA tumor was shown to be poorly immunogenic, and four weekly injections of BA cells alone or C. parvum alone did not confer significant immunity. When BA cells and C. parvum were mixed, survival time was prolonged and most mice remained tumor-free. Hybrid cell lines derived from the BA tumor were produced in culture in unlimited quantities and were successfully used as immunogens. The addition of C. parvum to hybrids gave a significant incremental increase in survival when compared to the survival resulting from immunization by hybrids without adjuvant. When hybrids without adjuvant were used, several weekly injections were required for effective immunization. Irradiated and unirradiated hybrids were compared, and it was found that irradiation did not diminish hybrid immunogenicity. The potential problems and advantages of this concept of therapy are discussed.

Adenocarcinoma↗