Search for charged Higgs bosons in decays of top quarks in pp collisions at square root s = 1.96 TeV

We report on the first direct search for charged Higgs bosons decaying into cs in tt events produced by pp collisions at square root s = 1.96 TeV. The search uses a data sample corresponding to an integrated luminosity of 2.2 fb(-1) collected by the CDF II detector at Fermilab and looks for a resonance in the invariant mass distribution of two jets in the lepton + jets sample of tt candidates. We observe no evidence of charged Higgs bosons in top quark decays. Hence, 95% upper limits on the top quark decay branching ratio are placed at B(t --> H(+)b)< 0.1 to 0.3 for charged Higgs boson masses of 60 to 150 GeV/c(2) assuming B(H(+) --> cs)=1.0. The upper limits on B(t --> H(+)b) are also used as model-independent limits on the decay branching ratio of top quarks to generic scalar charged bosons beyond the standard model.

New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 1: radiostrontium and radiocaesium

Best estimates for the solid-liquid distribution coefficients (K(d)) of radiostrontium and radiocaesium for various soil types, were derived from geometric means (GM) calculated from grouping soils by texture and organic matter content, and also using soil cofactors governing soil-radionuclide interaction. The K(d) (Sr) GM for Sand, Loam, Clay and Organic groups were similar, although the value for the Sand group was significantly lower. The Sr cofactor approach, based on the ratios of cation exchange capacity (CEC) to Ca and Mg concentrations in the soil solution, leads to K(d) (Sr) GM with a lower variability, from which best estimates could be proposed. The K(d) (Cs) GM for Sand and Organic groups differed, although similar values were obtained for Loam and Clay groups. Grouping the K(d) (Cs) according to the Radiocaesium Interception Potential (RIP) and the RIP divided by the K concentration in the soil solution also allows to suggest K(d) (Cs) best estimates with a lower variability.

New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 2: naturally occurring radionuclides

Predicting the transfer of radionuclides in the environment for normal release, accidental, disposal or remediation scenarios in order to assess exposure requires the availability of an important number of generic parameter values. One of the key parameters in environmental assessment is the solid liquid distribution coefficient, K(d), which is used to predict radionuclide-soil interaction and subsequent radionuclide transport in the soil column. This article presents a review of K(d) values for uranium, radium, lead, polonium and thorium based on an extensive literature survey, including recent publications. The K(d) estimates were presented per soil groups defined by their texture and organic matter content (Sand, Loam, Clay and Organic), although the texture class seemed not to significantly affect K(d). Where relevant, other K(d) classification systems are proposed and correlations with soil parameters are highlighted. The K(d) values obtained in this compilation are compared with earlier review data.

New best estimates for radionuclide solid-liquid distribution coefficients in soils. Part 3: miscellany of radionuclides (Cd, Co, Ni, Zn, I, Se, Sb, Pu, Am, and others)

New best estimates for the solid-liquid distribution coefficient (K(d)) for a set of radionuclides are proposed, based on a selective data search and subsequent calculation of geometric means. The K(d) best estimates are calculated for soils grouped according to the texture and organic matter content. For a limited number of radionuclides this is extended to consider soil cofactors affecting soil-radionuclide interaction, such as pH, organic matter content, and radionuclide chemical speciation. Correlations between main soil properties and radionuclide K(d) are examined to complete the information derived from the best estimates with a rough prediction of K(d) based on soil parameters. Although there are still gaps for many radionuclides, new data from recent studies improve the calculation of K(d) best estimates for a number of radionuclides, such as selenium, antimony, and iodine.

Observation of electroweak single top-quark production

We report the observation of single top-quark production using 3.2 fb(-1) of pp[over ] collision data with sqrt[s]=1.96 TeV collected by the Collider Detector at Fermilab. The significance of the observed data is 5.0 standard deviations, and the expected sensitivity for standard model production and decay is in excess of 5.9 standard deviations. Assuming m(t) = 175 GeV/c(2), we measure a cross section of 2.3(-0.5);(+0.6)(stat + syst) pb, extract the CKM matrix-element value |V(tb)| = 0.91 + or - 0.11(stat + syst) + or - 0.07(theory), and set the limit |V(tb)| > 0.71 at the 95% C.L.

First observation of vector boson pairs in a hadronic final state at the tevatron collider

We present the first observation in hadronic collisions of the electroweak production of vector boson pairs (VV, V = W, Z) where one boson decays to a dijet final state. The data correspond to 3.5 fb(-1) of integrated luminosity of pp[over ] collisions at sqrt[s] = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We observe 1516 + or - 239(stat) + or - 144(syst) diboson candidate events and measure a cross section sigma(pp[over ]-->VV + X) of 18.0 + or - 2.8(stat) + or - 2.4(syst) + or -1.1(lumi) pb, in agreement with the expectations of the standard model.

Search for a fermiophobic Higgs boson decaying into diphotons in pp[over] collisions at sqrt[s] = 1.96 TeV

A search for a narrow diphoton mass resonance is presented based on data from 3.0 fb;{-1} of integrated luminosity from pp[over ] collisions at sqrt[s] = 1.96 TeV collected by the CDF experiment. No evidence of a resonance in the diphoton mass spectrum is observed, and upper limits are set on the cross section times branching fraction of the resonant state as a function of Higgs boson mass. The resulting limits exclude Higgs bosons with masses below 106 GeV/c;{2} at a 95% Bayesian credibility level for one fermiophobic benchmark model.

Search for the production of narrow tb[over] resonances in 1.9 fb;{-1} of pp[over] collisions at sqrt[s] = 1.96 TeV

We present new limits on resonant tb[over] production in pp[over] collisions at sqrt[s] = 1.96 TeV, using 1.9 fb;{-1} of data recorded with the CDF II detector at the Fermilab Tevatron. We reconstruct a candidate tb[over] mass in events with a lepton, neutrino candidate, and two or three jets, and search for anomalous tb[over] production as modeled by W;{'} --> tb[over]. We set a new limit on a right-handed W;{'} with standard model-like coupling, excluding any mass below 800 GeV/c;{2} at 95% C.L. The cross section for any narrow, resonant tb[over] production between 750 and 950 GeV/c;{2} is found to be less than 0.28 pb at 95% C.L. We also present an exclusion of the W;{'} coupling strength versus W;{'} mass over the range 300-950 GeV/c;{2}.

Observation of new charmless decays of bottom hadrons

We search for new charmless decays of neutral b hadrons to pairs of charged hadrons, using 1 fb(-1) of data collected by the CDF II detector at the Fermilab Tevatron. We report the first observation of the Bs0-->K-pi+ decay and measure B(Bs0-->K-pi+)=(5.0+/-0.7(stat)+/-0.8(syst))x10(-6). We also report the first observation of charmless b-baryon decays, and measure B(Lambdab0-->ppi-)=(3.5+/-0.6(stat)+/-0.9(syst))x10(-6) and B(Lambdab0-->pK-)=(5.6+/-0.8(stat)+/-1.5(syst))x10(-6). No evidence is found for other modes, and we set the limit B(Bs0-->pi+pi;-)<1.2x10(-6) at 90% C.L.

Search for long-lived massive charged particles in 1.96 TeV pp collisions

We performed a signature-based search for long-lived charged massive particles produced in 1.0 fb-1 of pp[over ] collisions at sqrt[s]=1.96 TeV, collected with the CDF II detector using a high transverse-momentum (pT) muon trigger. The search used time of flight to isolate slowly moving, high-pT particles. One event passed our selection cuts with an expected background of 1.9+/-0.2 events. We set an upper bound on the production cross section and, interpreting this result within the context of a stable scalar top-quark model, set a lower limit on the particle mass of 249 GeV/c2 at 95% C.L.

Evidence for a narrow near-threshold structure in the J/psivarphi mass spectrum in B;{+} --> J/psivarphiK;{+} decays

Evidence is reported for a narrow structure near the J/psivarphi threshold in exclusive B;{+} --> J/psivarphiK;{+} decays produced in p[over]p collisions at sqrt[s] = 1.96 TeV. A signal of 14 +/- 5 events, with statistical significance in excess of 3.8 standard deviations, is observed in a data sample corresponding to an integrated luminosity of 2.7 fb;{-1}, collected by the CDF II detector. The mass and natural width of the structure are measured to be 4143.0 +/- 2.9(stat) +/- 1.2(syst) MeV/c;{2} and 11.7_{-5.0};{+8.3}(stat) +/- 3.7(syst) MeV/c;{2}.

Observation of exclusive charmonium production and gammagamma --> micro;{+}micro;{-} in pp[over] collisions at sqrt[s] = 1.96 TeV

In CDF we have observed the reactions p + p[over] --> p + X + p[over], with X being a centrally produced J/psi, psi(2S), or chi_{c0}, and gammagamma-->micro;{+}micro;{-} in pp[over] collisions at sqrt[s] = 1.96 TeV. The event signature requires two oppositely charged central muons, and either no other particles or one additional photon detected. Exclusive vector meson production is as expected for elastic photoproduction, gamma + p --> J/psi(psi(2S)) + p, observed here for the first time in hadron-hadron collisions. We also observe exclusive chi_{c0} --> J/psi + gamma. The cross sections dsigma/dy|_{y = 0} for J/psi, psi(2S), and chi_{c0} are 3.92 +/- 0.25(stat) +/- 0.52(syst) nb, 0.53 +/- 0.09(stat) +/- 0.10(syst) nb, and 76 +/- 10(stat) +/- 10(syst) nb, respectively, and the continuum is consistent with QED. We put an upper limit on the cross section for Odderon exchange in exclusive J/psi production.

Measurement of the k(T) distribution of particles in jets produced in pp collisions at sqrt(s)=1.96 TeV

We present a measurement of the transverse momentum with respect to the jet axis (k(t)) of particles in jets produced in pp collisions at sqrt(s)=1.96 TeV. Results are obtained for charged particles in a cone of 0.5 radians around the jet axis in events with dijet invariant masses between 66 and 737 GeV/c(2). The experimental data are compared to theoretical predictions obtained for fragmentation partons within the framework of resummed perturbative QCD using the modified leading log and next-to-modified leading log approximations. The comparison shows that trends in data are successfully described by the theoretical predictions, indicating that the perturbative QCD stage of jet fragmentation is dominant in shaping basic jet characteristics.

First measurement of the tt[over ] differential cross section dsigma/dM_{tt[over ]} in pp[over ] collisions at sqrt[s]=1.96 TeV

We present a measurement of the tt[over ] differential cross section with respect to the tt[over ] invariant mass, dsigma/dM_{tt[over ]}, in pp[over ] collisions at sqrt[s]=1.96 TeV using an integrated luminosity of 2.7 fb;{-1} collected by the CDF II experiment. The tt[over ] invariant mass spectrum is sensitive to a variety of exotic particles decaying into tt[over ] pairs. The result is consistent with the standard model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions.

Search for exclusive Z-boson production and observation of high-mass pp[over ]-->pgammagammap[over ]-->pl;{+}l;{-}p[over ] events in pp[over ] collisions at sqrt[s]=1.96 TeV

This Letter presents a search for exclusive Z boson production in proton-antiproton collisions at sqrt[s]=1.96 TeV, using the CDF II detector. No exclusive Z-->l;{+}l;{-} candidates are observed and the first upper limit on the exclusive Z cross section in hadron collisions is found to be sigma_{excl}(Z)<0.96 pb at 95% confidence level. In addition, eight candidate exclusive dilepton events from the process pp[over ]-->pgammagammap[over ]-->pl;{+}l;{-}p[over ] are observed, and a measurement of the cross section for M_{ll}>40 GeV/c;{2} and |eta_{l}|<4 is found to be sigma=0.24_{-0.10};{+0.13} pb, which is consistent with the standard model prediction.

Search for Gluino-Mediated Bottom Squark Production in pp[over ] Collisions at sqrt[s]=1.96 TeV

We report on a search for the supersymmetric partner of the bottom quark produced from gluino decays in data from 2.5 fb;{-1} of integrated luminosity collected by the Collider Detector at Fermilab at sqrt[s]=1.96 TeV. Candidate events are selected requiring two or more jets and large missing transverse energy. At least two of the jets are required to be tagged as originating from a b quark to enhance the sensitivity. The results are in good agreement with the prediction of the standard model processes, giving no evidence for gluino decay to bottom squarks. This result constrains the gluino-pair-production cross section to be less than 40 fb at 95% credibility level for a gluino mass of 350 GeV/c;{2}.

Search for the decays B_{(s)};{0} --> e;{+} micro;{-} and B_{(s)};{0} --> e;{+} e;{-} in CDF run II

We report results from a search for the lepton flavor violating decays B_{s};{0} --> e;{+} micro;{-} and B;{0} --> e;{+} micro;{-}, and the flavor-changing neutral-current decays B_{s};{0} --> e;{+} e;{-} and B;{0} --> e;{+} e;{-}. The analysis uses data corresponding to 2 fb;{-1} of integrated luminosity of pp[over ] collisions at sqrt[s] = 1.96 TeV collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron. The observed number of B0 and B_{s};{0} candidates is consistent with background expectations. The resulting Bayesian upper limits on the branching ratios at 90% credibility level are B(B_{s};{0} --> e;{+} micro;{-}) < 2.0 x 10;{-7}, B(B;{0} --> e;{+} micro;{-}) < 6.4 x 10;{-8}, B(B_{s};{0} --> e;{+} e;{-}) < 2.8 x 10;{-7}, and B(B;{0} --> e;{+} e;{-}) < 8.3 x 10;{-8}. From the limits on B(B_{(s)};{0} --> e;{+} micro;{-}), the following lower bounds on the Pati-Salam leptoquark masses are also derived: M_{LQ}(B_{s};{0} --> e;{+} micro;{-}) > 47.8 TeV/c;{2}, and M_{LQ}(B;{0} --> e;{+} micro;{-}) > 59.3 TeV / c;{2}, at 90% credibility level.

Oncologic patients in the emergency room

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Background: Cancer is a very frequent pathology with a gradual increase of its prevalence. Oncologic patients are exposed to suffer many complications which may need emergency attention. The aim of this study is to describe patients which consult in the emergency room and frecuency of different causes of complaint. Methods: Between October 2007 and October 2008, we collected all oncologic patients who consulted in our emergency room. We describe tumor location and causes of complaint. Results: 560 oncologic patients were attended in 12 months (median 12 per week). By tumor location, 134 (23,9%) patients had not small cell lung cancer (NSCLC), 101 (18%) colorrectal cancer, 64 (11.4%) breast cancer, and 261 (53%) other malignancies. Of all patients, 440 (82.7%) had stage IV disease and 318 (56.8%) were receiving chemotherapy treatment The most common causes to complaint were oncologic pain (22.5%), fever (17.5%), dysphnea (12.7%), neurologic symptoms (9.1%), and asthenia (8.6%). Conclusions: Oncologic patients consult frecuently in the emergency room, mainly those with NSCLC and colorrectal cancer. Metastasic disease and chemotherapy treatment are common too. Oncologic pain, fever and dysphnea are the most frequent causes of complaint,with an important impact on their quality of life.

No significant financial relationships to disclose.

Evaluation of neurological symptoms in oncologic patients at the emergency department

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Background: Neurological symptoms in cancer patients are common and some of them represent a potentially serious situation. They are a frequent cause of complaint at the Emergency Department (ED). The aim of the study is to describe the profile of cancer patient who consult at ED for neurological symptoms, their diagnosis and management. Methods: From October 2007 to October 2008, all cancer patients treated at the ED of our hospital were prospectively collected. The reasons for consultation, diagnosis and clinical management are described. Results: A total of 560 cancer patients were enrolled. Of them, 61 patients (11%) consulted for a neurologic symptom: 50 of these patients (82%) were stage IV disease and 30 (49,2%) were receiving chemotherapy treatment. Of the total of patients, 14 (23%) had lung cancer; 10 patients (16%) had colorectal cancer; and 8 patients (13%) had primary central nervous system tumor. Most frequent causes of complaint were: low level of consciousness, 13 patients (21%); mobility deficit, 12 patients (19%); syncope, 9 patients (15%) and comitial crisis, 6 patients (10%). Of the patients who consulted for a neurological symptom, 52% of cases (32 patients) the cause was a structural lesion of central nervous system. Tumor progression was the diagnosis made in 27 patients (44,3%), in 14 patients (23%) the diagnosis was a metabolic alteration. A 69% of patients (42 patients) required hospitalization, 26% was discharged (16 patients) and 5% (3 patients) needed to be under observation during at least 24 hours. Conclusions: Neurological symptom is a frequent cause of complaint at ED for cancer patients. especially in patients in advanced stages. The most frequent diagnosis made because of these symptoms is tumor progression. Metabolic alterations are also an important diagnosis because of their frequency and because they can be solved by medical treatment. Most patients who consult for neurological symptoms need hospitalization.

No significant financial relationships to disclose.

Adverse events due to chemotherapy in emergency room

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Background: High rates of mortality due to cancer make necessary improve oncologic treatments. Relationship between adverse events and chemotherapy schedule and dose is well known thanks to large observational studies. Our study´s objective is to estimate the prevalence of chemotherapy adverse events in oncologic patients attended in Emergency room. Methods: From October 2007 to October 2008 560 patients were recollected. It was revised tumors location and stage, chemotherapy schedule and date of the last treatment, diagnosis and therapheutic in Emergency. Results: 87 of the 560 patients (15%) were attended in Emergency room because of chemotherapy toxicity. The most common cause of consultation was fever (27 patients, 31%) followed by diarrhea (18 patients, 20.7%) and nausea-vomiting (12 patients, 13.8%). Most of the patients were being treated with classic chemotherapy schedules (70.1%). Comparing as a whole all the chemotherapy schedules there were not statistically significant differences due to toxicity between them. Nevertheless analyzing by subgroups we found there was no difference between toxicity in patients treated with classic chemotherapy and chemotherapy plus target agents (33.8% vs 5.5%, p=0.30), but there was differences between chemotherapy and target agents in monotherapy (33.8% vs 13.2%, p<0.05). In 39 of the 87 patients (39%) admission was required with a good evolution in most of them. Conclusions: Adverse events due to chemotherapy is a common cause of consultation in Emergency room. In our sample new target agents did not add toxicity to classic chemotherapy and given as monotherapy they had really good tolerance. More randomized studies are necessary to do a better evaluation of adverse events due to new agents.

No significant financial relationships to disclose.

Fever in cancer patients as a cause of attendance in emergency room

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Background: Normal human body temperature displays a circadian rhythm, ranging from 36.1 C or lower in predawn hours to 37.4 C or higher in the afternoon. Abnormal elevation of temperature occurs as a result of hyperthermia or fever. Cancer patients frequently experience fever. Nearly two-thirds of the cases of fever in patients with prolonged neutropenia could be attributed to infection, a major cause of morbidity in cancer patients. Purpose: The aim of our study is to evaluate the prevalence of cancer patients who were attended in the emergency room for fever, the diagnosis and clinical management. Methods: From October 2007 to October 2008, 560 cancer patients were seen in the emergency department of the University Hospital of Zaragoza. The purpose of this paper is to describe the characteristics of patients who presented with fever. Results: A total of 560 patients were seen. Ninety-eight (17.5%) presented with fever. 63% of patients were stage IV. Cancer tumor type, 35 had lung cancer (35.7%), 14 had breast cancer (14.3%), 9 had colorectal cancer (9.2%), 9 had urothelial cancer (9.2%), 5 had head neck cancer (5.1%), 5 had pancreatic cancer (5.1%), 3 had esophageal cancer (3%), 2 had prostate cancer (2%), and 14,3% had other neoplasm. 18 patients (18.36%) had been received chemotherapy treatment in a period of 10 days before. they were attended in emergency room. By diagnosis: 23 patients (23,46%) were diagnosed of febrile neutropenia, and 19 of them (82,6%) required admission to the hospital. 30 were diagnosed of respiratory tract infection (30,6%), 12 were diagnosed of urinary infection (12.24%). Considering all the patients who presented with fever: 45 patients were sent home with new treatment (45,9%), 6 patients were observed for 24 hours in the emergency room (6.2%) and 47 patients required admission to the hospital (47.9%). Conclusions: Fever in cancer patients remains a challenge, and the differentiation between infectious and non-infectious causes at onset of fever is very difficult. Despite all the prophylactic measures, infection is still the principal cause. Infection in the immunocompromised host is a serious clinical situation due to high morbimortality and is one of the most frequent complications in the patient with cancer.

No significant financial relationships to disclose.