Showing papers by "Université Paris-Saclay published in 2008"

Improved Cosmological Constraints from New, Old, and Combined Supernova Data Sets

Abstract: We present a new compilation of Type Ia supernovae (SNe Ia), a new data set of low-redshift nearby-Hubble-flow SNe, and new analysis procedures to work with these heterogeneous compilations This "Union" compilation of 414 SNe Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy Survey and ESSENCE Survey, the older data sets, as well as the recently extended data set of distant supernovae observed with the Hubble Space Telescope (HST) A single, consistent, and blind analysis procedure is used for all the various SN Ia subsamples, and a new procedure is implemented that consistently weights the heterogeneous data sets and rejects outliers We present the latest results from this Union compilation and discuss the cosmological constraints from this new compilation and its combination with other cosmological measurements (CMB and BAO) The constraint we obtain from supernovae on the dark energy density is ΩΛ = 0713+ 0027−0029(stat)+ 0036−0039(sys) , for a flat, ΛCDM universe Assuming a constant equation of state parameter, w, the combined constraints from SNe, BAO, and CMB give w = − 0969+ 0059−0063(stat)+ 0063−0066(sys) While our results are consistent with a cosmological constant, we obtain only relatively weak constraints on a w that varies with redshift In particular, the current SN data do not yet significantly constrain w at z > 1 With the addition of our new nearby Hubble-flow SNe Ia, these resulting cosmological constraints are currently the tightest available

Bcl-2 family members: dual regulators of apoptosis and autophagy.

Abstract: The essential autophagy protein and haplo-insufficient tumor suppressor, Beclin 1, interacts with several cofactors (Ambra1, Bif-1, UVRAG) to activate the lipid kinase Vps34, thereby inducing autophagy. In normal conditions, Beclin 1 is bound to and inhibited by Bcl-2 or the Bcl-2 homolog Bcl-X(L). This interaction involves a Bcl-2 homology 3 (BH3) domain in Beclin 1 and the BH3 binding groove of Bcl-2/Bcl-X(L). Other proteins containing BH3 domains, called BH3-only proteins, can competitively disrupt the interaction between Beclin 1 and Bcl-2/Bcl-X(L) to induce autophagy. Nutrient starvation, which is a potent physiologic inducer of autophagy, can stimulate the dissociation of Beclin 1 from its inhibitors, either by activating BH3-only proteins (such as Bad) or by posttranslational modifications of Bcl-2 (such as phosphorylation) that may reduce its affinity for Beclin 1 and BH3-only proteins. Thus, anti-apoptotic Bcl-2 family members and pro-apoptotic BH3-only proteins may participate in the inhibition and induction of autophagy, respectively. This hitherto neglected crosstalk between the core machineries regulating autophagy and apoptosis may redefine the role of Bcl-2 family proteins in oncogenesis and tumor progression.

Observation of the suppression of the flux of cosmic rays above 4x10(19) eV

Abstract: The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.

Chemotherapy in addition to supportive care improves survival in advanced non-small-cell lung cancer: A systematic review and meta-analysis of individual patient data from 16 randomized controlled trials

Abstract: PURPOSE Since our individual patient data (IPD) meta-analysis (MA) of supportive care and chemotherapy for non-small-cell lung cancer (NSCLC), published in 1995, many trials have been completed. An updated, IPD MA has been carried out to assess newer regimens and determine conclusively the effect of chemotherapy. METHODS Systematic searches for randomized controlled trials (RCTs) were undertaken, followed by central collection, checking, and reanalysis of updated IPD. Results from RCTs were combined to calculate individual and pooled hazard ratios (HRs). RESULTS Data were obtained from 2,714 patients from 16 RCTs. There were 1,293 deaths among 1,399 patients assigned supportive care and chemotherapy and 1,240 among 1,315 assigned supportive care alone. Results showed a significant benefit of chemotherapy (HR, 0.77; 95% CI, 0.71 to 0.83; P

Motesanib diphosphate in progressive differentiated thyroid cancer.

Abstract: BACKGROUND: The expression of vascular endothelial growth factor (VEGF) is characteristic of differentiated thyroid cancer and is associated with aggressive tumor behavior and a poor clinical outcome. Motesanib diphosphate (AMG 706) is a novel oral inhibitor of VEGF receptors, platelet-derived growth-factor receptor, and KIT. METHODS: In an open-label, single-group, phase 2 study, we treated 93 patients who had progressive, locally advanced or metastatic, radioiodine-resistant differentiated thyroid cancer with 125 mg of motesanib diphosphate, administered orally once daily. The primary end point was an objective response as assessed by an independent radiographic review. Additional end points included the duration of the response, progression-free survival, safety, and changes in serum thyroglobulin concentration. RESULTS: Of the 93 patients, 57 (61%) had papillary thyroid carcinoma. The objective response rate was 14%. Stable disease was achieved in 67% of the patients, and stable disease was maintained for 24 weeks or longer in 35%; 8% had progressive disease as the best response. The Kaplan-Meier estimate of the median duration of the response was 32 weeks (the lower limit of the 95% confidence interval [CI] was 24; the upper limit could not be estimated because of an insufficient number of events); the estimate of median progression-free survival was 40 weeks (95% CI, 32 to 50). Among the 75 patients in whom thyroglobulin analysis was performed, 81% had decreased serum thyroglobulin concentrations during treatment, as compared with baseline levels. The most common treatment-related adverse events were diarrhea (in 59% of the patients), hypertension (56%), fatigue (46%), and weight loss (40%). CONCLUSIONS: Motesanib diphosphate can induce partial responses in patients with advanced or metastatic differentiated thyroid cancer that is progressive. (ClinicalTrials.gov number, NCT00121628.)

Complete Pathologic Response After Preoperative Chemotherapy for Colorectal Liver Metastases: Myth or Reality?

Abstract: Purpose Complete clinical response (CCR) of colorectal liver metastases (CLM) following chemotherapy is of limited predictive value for complete pathologic response (CPR) and cure of the disease. The objective of this study was to determine predictive factors of CPR as well as its impact on survival. Patients and Methods From January 1985 to July 2006, 767 consecutive patients with CLM underwent liver resection after systemic chemotherapy. Patients with CPR were compared with patients without CPR. Results Twenty-nine of 767 (4%) patients had CPR, and none of these 29 patients had CCR. Patients with CPR (mean age, 54 years) had a mean number of 3.3 metastases at diagnosis (mean size, 29.3 mm). Objective response and stable disease were observed in 79% and 21% of cases, respectively. Postoperative mortality rate was 0%. After a median follow-up of 52.2 months (range, 1.1 to 193.0 months), overall 5-year survival was 76% for patients with CPR compared with 45% for patients without CPR (P = .004). Independent...

Measurement of the inclusive jet cross section in pp̄ collisions at s=1.96TeV

Abstract: We report on a measurement of the inclusive jet cross section in p (p) over bar collisions at a center-of-mass energy root s = 1.96 TeV using data collected by the D0 experiment at the Fermilab Tevatron Collider corresponding to an integrated luminosity of 0: 70 fb(-1). The data cover jet transverse momenta from 50 to 600 GeV and jet rapidities in the range -2.4 to 2.4. Detailed studies of correlations between systematic uncertainties in transverse momentum and rapidity are presented, and the cross section measurements are found to be in good agreement with next-to-leading order QCD calculations.

Single-shot time-resolved measurements of nanosecond-scale spin-transfer induced switching: stochastic versus deterministic aspects.

Abstract: Using high bandwidth resistance measurements, we study the single-shot response of tunnel junctions subjected to spin torque pulses. After the pulse onset, the switching proceeds by a ns-scale incubation delay during which the resistance is quiet, followed by a 400 ps transition terminated by a large ringing that is damped progressively. While the incubation delay fluctuates significantly, the resistance traces are reproducible once this delay is passed. After switching, the time-resolved resistance traces indicate micromagnetic configurations that are rather spatially coherent.

Is hepatic resection justified after chemotherapy in patients with colorectal liver metastases and lymph node involvement

Abstract: Purpose For patients with colorectal liver metastases (CLM), regional lymph node (RLN) involvement is one of the worst prognostic factors. The objective of this study was to evaluate the ability of a multidisciplinary approach, including preoperative chemotherapy and hepatectomy, to improve patient outcomes. Patients and Methods Outcomes for a consecutively treated group of patients with CLM and simultaneous RLN involvement were compared with a cohort of patients without RLN involvement. Univariate and multivariate analysis of clinical variables was used to identify prognostic factors in this high-risk group. Results Of the 763 patients who underwent resection at our institution for CLM between 1992 and 2006, 47 patients (6%) were treated with hepatectomy and simultaneous lymphadenectomy. All patients had received preoperative chemotherapy. Five-year overall survival (OS) for patients with and without RLN involvement were 18% and 53%, respectively (P < .001). Five-year disease-free survival rates were 11%...

Upper limit on the diffuse flux of ultrahigh energy tau neutrinos from the Pierre Auger Observatory

Abstract: The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from ντ charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of ντ at EeV energies. Assuming an Eν-2 differential energy spectrum the limit set at 90% C.L. is Eν2dNντ/dEν<1.3×10-7GeVcm-2s-1sr-1 in the energy range 2×1017eV

Measurement of Bs0 Mixing Parameters from the Flavor-Tagged Decay Bs0→J/ψ

Abstract: From an analysis of the flavor-tagged decay B-s(0)-> J/psi phi we obtain the width difference between the B-s(0) light and heavy mass eigenstates, Delta Gamma(s)=0.19 +/- 0.07(stat)(-0.01)(+0.02)(syst) ps(-1), and the CP-violating phase, phi(s)=-0.57(-0.30)(+0.24)(stat)(-0.02)(+0.08)(syst). The allowed 90% CL intervals of Delta Gamma(s) and phi(s) are 0.06

Measurements of e+e-→K+K-η, K+K-π0, and Ks0K±π cross sections using initial state radiation events

Abstract: This paper reports measurements of processes: e+e-→γKS0K±π∓, e+e-→γK+K-π0, e+e-→γϕη, and e+e-→γϕπ0. The initial-state radiated photon allows to cover the hadronic final state in the energy range from thresholds up to ≈4.6 GeV. The overall size of the data sample analyzed is 232 fb-1, collected by the BABAR detector running at the PEP-II e+e- storage ring. From the Dalitz plot analysis of the KS0K±π∓ final state, moduli, and relative phase of the isoscalar and the isovector components of the e+e-→KK*(892) cross section are determined. Parameters of ϕ and ρ recurrences are also measured, using a global fitting procedure which exploits the interconnection among amplitudes, moduli, and phases of the e+e-→KS0K±π∓, K+K-π0, ϕη final states. The cross section for the OZI-forbidden process e+e-→ϕπ0, and the J/ψ branching fractions to KK*(892) and K+K-η are also measured.

Observation of Y(3940) -> J/psi omega in B -> J/psi omega K at BABAR

Abstract: We present a study of the decays B;{0,+}-->J/psiomegaK;{0,+} using 383x10;{6} BB[over ] events obtained with the BABAR detector at PEP-II. We observe Y(3940)-->J/psiomega, with mass 3914.6_{-3.4};{+3.8}(stat)+/-2.0(syst) MeV/c;{2}, and width 34_{-8};{+12}(stat)+/-5(syst) MeV. The ratio of B0 and B+ decay to YK is 0.27_{-0.23};{+0.28}(stat)-0.01+0.04(syst), and the relevant B0 and B+ branching fractions are reported.

Proton- and reductant-assisted dioxygen activation by a nonheme iron(II) complex to form an oxoiron(IV) intermediate.

Abstract: With the aid of HClO{sub 4} as proton and BPh{sub 4}{sup -} as electron source, the Fe complex of a pentadentate pyridyl-appended cyclam ligands can activate dioxygen to yield the corresponding oxoiron(IV) complex (see scheme; TMC-py=1-(2'-pyridylmethyl)-4,8,11-trimethyl-1,4,8,11-tetraazacyclotetradecane; C gray, Fe magneta, N blue, O red). This transformation is proposed to occur via a hydroperoxoiron(III) intermediate.

Differential Accumulation of Retroelements and Diversification of NB-LRR Disease Resistance Genes in Duplicated Regions Following Polyploidy in the Ancestor of Soybean

Abstract: The genomes of most, if not all, flowering plants have undergone whole genome duplication events during their evolution. The impact of such polyploidy events is poorly understood, as is the fate of most duplicated genes. We sequenced an approximately 1 million-bp region in soybean (Glycine max) centered on the Rpg1-b disease resistance gene and compared this region with a region duplicated 10 to 14 million years ago. These two regions were also compared with homologous regions in several related legume species (a second soybean genotype, Glycine tomentella, Phaseolus vulgaris, and Medicago truncatula), which enabled us to determine how each of the duplicated regions (homoeologues) in soybean has changed following polyploidy. The biggest change was in retroelement content, with homoeologue 2 having expanded to 3-fold the size of homoeologue 1. Despite this accumulation of retroelements, over 77% of the duplicated low-copy genes have been retained in the same order and appear to be functional. This finding contrasts with recent analyses of the maize (Zea mays) genome, in which only about one-third of duplicated genes appear to have been retained over a similar time period. Fluorescent in situ hybridization revealed that the homoeologue 2 region is located very near a centromere. Thus, pericentromeric localization, per se, does not result in a high rate of gene inactivation, despite greatly accelerated retrotransposon accumulation. In contrast to low-copy genes, nucleotide-binding-leucine-rich repeat disease resistance gene clusters have undergone dramatic species/homoeologue-specific duplications and losses, with some evidence for partitioning of subfamilies between homoeologues.

Measurement of the B→Xsγ branching fraction and photon energy spectrum using the recoil method

Abstract: We present a measurement of the branching fraction and photon-energy spectrum for the decay B -> X-s gamma using data from the BABAR experiment. The data sample corresponds to an integrated luminosity of 210 fb(-1), from which approximately 680 000 B (B) over bar events are tagged by a fully reconstructed hadronic decay of one of the B mesons. In the decay of the second B meson, an isolated high-energy photon is identified. We measure B(B -> X-s gamma) = (3.66 +/- 0.85(stat) +/- 0.60(syst)) x 10(-4) for photon energies E-gamma above 1.9 GeV in the B rest frame. From the measured spectrum we calculate the first and second moments for different minimum photon energies, which are used to extract the heavy-quark parameters m(b) and mu(2)(pi). In addition, measurements of the direct CP asymmetry and isospin asymmetry are presented.

Quantitative constraints on the transport properties of hot partonic matter from semi-inclusive single high transverse momentum pion suppression in Au+Au collisions at sNN=200 GeV

Abstract: The PHENIX experiment has measured the suppression of semi-inclusive single high-transverse-momentum pi(0)'s in Au+Au collisions at root s(NN) = 200 GeV. The present understanding of this suppression is in terms of energy loss of the parent (fragmenting) parton in a dense color-charge medium. We have performed a quantitative comparison between various parton energy-loss models and our experimental data. The statistical point-to-point uncorrelated as well as correlated systematic uncertainties are taken into account in the comparison. We detail this methodology and the resulting constraint on the model parameters, such as the initial color-charge density dN(g)/dy, the medium transport coefficient , or the initial energy-loss parameter epsilon(0). We find that high-transverse-momentum pi(0) suppression in Au+Au collisions has sufficient precision to constrain these model-dependent parameters at the +/- 20-25% (one standard deviation) level. These constraints include only the experimental uncertainties, and further studies are needed to compute the corresponding theoretical uncertainties.

Genetic investigation of four meiotic genes in women with premature ovarian failure.

Abstract: Objective: The goal of this study was to determine whether mutations of meiotic genes, such as disrupted meiotic cDNA (DMC1), MutS homolog (MSH4), MSH5 ,a ndS. cerevisiae homolog (SPO11), were associated with premature ovarian failure (POF). Design: Case–control study. Methods: Blood sampling, karyotype, hormonal dosage, ultrasound, and ovarian biopsy were carried out on most patients. However, the main outcome measure was the sequencing of genomic DNA from peripheral blood samples of 41 women with POF and 36 fertile women (controls). Results: A single heterozygous missense mutation, substitution of a cytosine residue with thymidine in exon 2 ofMSH5, was found in two Caucasian women in whom POF developed at 18 and 36 years of age. This mutation resulted in replacement of a non-polar amino acid (proline) with a polar amino acid (serine) at position 29 (P29S). Neither 36 control women nor 39 other patients with POF possessed this genetic perturbation. Another POF patient of African origin showed a homozygous nucleotide change in the tenth of DMC1 gene that led to an alteration of the amino acid composition of the protein (M200V). Conclusions: The symptoms of infertility observed in the DMC1 homozygote mutation carrier and in both patients with a heterozygous substitution in exon 2 of theMSH5 gene provide indirect evidence of the role of genes involved in meiotic recombination in the regulation of ovarian function. MSH5 and DMC1 mutations may be one explanation for POF, albeit uncommon.

J/ψ production in sNN=200GeV Cu+Cu collisions

Abstract: Yields for J/psi production in Cu+Cu collisions at root s(NN) = 200 GeV have been measured over the rapidity range |y|< 2.2 and compared with results in p+p and Au+Au collisions at the same energy. The Cu+Cu data offer greatly improved precision over existing Au+Au data for J/psi production in collisions with small to intermediate numbers of participants, in the range where the quark-gluon plasma transition threshold is predicted to lie. Cold nuclear matter estimates based on ad hoc fits to d+Au data describe the Cu+Cu data up to N-part similar to 50, corresponding to a Bjorken energy density of at least 1.5 GeV/fm(3).

Improved Cellular Pharmacokinetics and Pharmacodynamics Underlie the Wide Anticancer Activity of Sagopilone

Abstract: Sagopilone (ZK-EPO) is the first fully synthetic epothilone undergoing clinical trials for the treatment of human tumors. Here, we investigate the cellular pathways by which sagopilone blocks tumor cell proliferation and compare the intracellular pharmacokinetics and the in vivo pharmacodynamics of sagopilone with other microtubule-stabilizing (or tubulin-polymerizing) agents. Cellular uptake and fractionation/localization studies revealed that sagopilone enters cells more efficiently, associates more tightly with the cytoskeleton, and polymerizes tubulin more potently than paclitaxel. Moreover, in contrast to paclitaxel and other epothilones [such as the natural product epothilone B (patupilone) or its partially synthetic analogue ixabepilone], sagopilone is not a substrate of the P-glycoprotein efflux pumps. Microtubule stabilization by sagopilone caused mitotic arrest, followed by transient multinucleation and activation of the mitochondrial apoptotic pathway. Profiling of the proapoptotic signal transduction pathway induced by sagopilone with a panel of small interfering RNAs revealed that sagopilone acts similarly to paclitaxel. In HCT 116 colon carcinoma cells, sagopilone-induced apoptosis was partly antagonized by the knockdown of proapoptotic members of the Bcl-2 family, including Bax, Bak, and Puma, whereas knockdown of Bcl-2, Bcl-X(L), or Chk1 sensitized cells to sagopilone-induced cell death. Related to its improved subcellular pharmacokinetics, however, sagopilone is more cytotoxic than other epothilones in a large panel of human cancer cell lines in vitro and in vivo. In particular, sagopilone is highly effective in reducing the growth of paclitaxel-resistant cancer cells. These results underline the processes behind the therapeutic efficacy of sagopilone, which is now evaluated in a broad phase II program.

Study of B→X(3872)K, with X(3872)→J/ψπ+π-

Abstract: We present measurements of the decays B+ -> X(3872) K+ and B0 -> X(3872) K0 with X(3872) -> Jpsi pi+ pi-. The data sample used, collected with the BABAR detector at the PEP-II e+e- asymmetric-energy storage ring, corresponds to 455 x 10^6 BBbar pairs. Branching fraction measurements of BF(B+ -> X(3872) K+) x BF(X(3872) -> Jpsi pi+ pi-) = (8.4 +/- 1.5 +/- 0.7) x 10^{-6} and BF(B0 -> X(3872) K0) x BF(X(3872) -> Jpsi pi+ pi- = (3.5 +/- 1.9 +/- 0.4) x 10^{-6} are obtained. We set an upper limit on the natural width of the X(3872) of Gamma < 3.3 MeV/c^2 at the 90% confidence level.

Evidence for Direct CP Violation from Dalitz-plot analysis of B+/- -> K+/- pi+/- pi-/+

Abstract: We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi+/- pi-/+. Using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, we measure CP-averaged branching fractions and direct CP asymmetries for intermediate resonant and nonresonant contributions. We find evidence for direct CP violation in the decay B+ -> rho0(770) K+, with a CP violation parameter A_CP = (+44 +/- 10 +/- 4 +5,-13)%.

Cold nuclear matter effects on J/ψ production as constrained by deuteron-gold measurements at sNN=200 GeV

Abstract: We present a new analysis of J/psi production yields in deuteron-gold collisions at root s(NN) =200 GeV using data taken from the PHENIX experiment in 2003 and previously published in S. S. Adler [Phys. Rev. Lett 96, 012304 (2006)]. The high statistics proton-proton J/psi data taken in 2005 are used to improve the baseline measurement and thus construct updated cold nuclear matter modification factors (R-dAu). A suppression of J/psi in cold nuclear matter is observed as one goes forward in rapidity (in the deuteron-going direction), corresponding to a region more sensitive to initial-state low-x gluons in the gold nucleus. The measured nuclear modification factors are compared to theoretical calculations of nuclear shadowing to which a J/psi (or precursor) breakup cross section is added. Breakup cross sections of sigma(breakup)=2.8(-1.4)(+1.7) (2.2(-1.5)(+1.6)) mb are obtained by fitting these calculations to the data using two different models of nuclear shadowing. These breakup cross-section values are consistent within large uncertainties with the 4.2 +/- 0.5 mb determined at lower collision energies. Projecting this range of cold nuclear matter effects to copper-copper and gold-gold collisions reveals that the current constraints are not sufficient to firmly quantify the additional hot nuclear matter effect.

Observation of the semileptonic decays B→D*τ-ν̄τ and evidence for B→Dτ-ν̄τ

Abstract: We present measurements of the semileptonic decays B--->D0tau-nutau, B--->D*0tau-nutau, B0-->D+tau-nutau, and B0-->D*+tau-nutau, which are potentially sensitive to non-standard model amplitudes. The data sample comprises 232x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector. From a combined fit to B- and B0 channels, we obtain the branching fractions B(B-->Dtau-nutau)=(0.86+/-0.24+/-0.11+/-0.06)% and B(B-->D*tau-nutau)=(1.62+/-0.31+/-0.10+/-0.05)% (normalized for the B0), where the uncertainties are statistical, systematic, and normalization-mode-related.

Exclusive branching-fraction measurements of semileptonic τ decays into three charged hadrons, into φπ-ντ, and into φk-ντ

Abstract: Using a data sample corresponding to an integrated luminosity of 342 fb(-1) collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, we measure B(tau(-)->pi(-)pi(-)pi(+)nu(tau)(ex.K-S(0)))=(8.83 +/- 0.01 +/- 0.13)%, B(tau(-)-> K-pi(-)pi(+)nu(tau)(ex.K-S(0)))=(0.273 +/- 0.002 +/- 0.009)%, B(tau(-)-> K-pi K--(+)nu(tau))=(0.1346 +/- 0.0010 +/- 0.0036)%, and B(tau(-)-> K-K-K+nu(tau))=(1.58 +/- 0.13 +/- 0.12)x10(-5), where the uncertainties are statistical and systematic, respectively. These include significant improvements over previous measurements and a first measurement of B(tau(-)-> K-K-K+nu(tau)) in which no resonance structure is assumed. We also report a first measurement of B(tau(-)->phi pi(-)nu(tau))=(3.42 +/- 0.55 +/- 0.25)x10(-5), a new measurement of B(tau(-)->phi K-nu(tau))=(3.39 +/- 0.20 +/- 0.28)x10(-5) and a first upper limit on B(tau(-)-> K-K-K+nu(tau)(ex.phi)).

Free rota–baxter algebras and rooted trees

Abstract: A Rota–Baxter algebra, also known as a Baxter algebra, is an algebra with a linear operator satisfying a relation, called the Rota–Baxter relation, that generalizes the integration by parts formula. Most of the studies on Rota–Baxter algebras have been for commutative algebras. Two constructions of free commutative Rota–Baxter algebras were obtained by Rota and Cartier in the 1970s and a third one by Keigher and one of the authors in the 1990s in terms of mixable shuffles. Recently, noncommutative Rota–Baxter algebras have appeared both in physics in connection with the work of Connes and Kreimer on renormalization in perturbative quantum field theory, and in mathematics related to the work of Loday and Ronco on dendriform dialgebras and trialgebras. This paper uses rooted trees and forests to give explicit constructions of free noncommutative Rota–Baxter algebras on modules and sets. This highlights the combinatorial nature of Rota–Baxter algebras and facilitates their further study. As an application, w...

Improved measurement of the CKM angle gamma in B--/+->(DK(*)-/+)-K-(*) decays with a Dalitz plot analysis of D decays to K-S(0)pi(+)pi(-) and (KSK+K-)-K-0

Abstract: We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic uncertainty and the third reflects the uncertainty on the description of the Dalitz plot distributions. The corresponding two standard deviation region is 29{sup o} < {gamma} < 122{sup o}. This result has a significance of direct CP violation ({gamma} {ne} 0) of 3.0 standard deviations.

Onset of π0 suppression studied in Cu+Cu collisions at sNN=22.4, 62.4, and 200 GeV

Abstract: Neutral pion transverse momentum (p(T)) spectra at midrapidity (|y| less than or similar to 0.35) were measured in Cu + Cu collisions at root s(NN) = 22.4, 62.4, and 200 GeV. Relative to pi(0) yields in p + p collisions scaled by the number of inelastic nucleon-nucleon collisions (N-coll) the pi(0) yields for p(T) greater than or similar to 2 GeV/c in central Cu + Cu collisions are suppressed at 62.4 and 200 GeV whereas an enhancement is observed at 22.4 GeV. A comparison with a jet-quenching model suggests that final state parton energy loss dominates in central Cu + Cu collisions at 62.4 and 200 GeV, while the enhancement at 22.4 GeV is consistent with nuclear modifications in the initial state alone.