D. M. Asner

Bio: D. M. Asner is an academic researcher from Pacific Northwest National Laboratory. The author has contributed to research in topics: Physics & Large Hadron Collider. The author has an hindex of 40, co-authored 112 publications receiving 31378 citations. Previous affiliations of D. M. Asner include Carleton University & CERN.

Study of the semileptonic charm decays D0→π-e+νe, D+→π0e+νe, D0→K-e+νe, and D+→K̄0e+νe

Abstract: Using a sample of 1.8 million $D\overline{D}$ mesons collected at the $\ensuremath{\psi}(3770)$ with the CLEO-c detector, we study the semileptonic decays ${D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{ u}}_{e}$, ${D}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{e}^{+}{\ensuremath{ u}}_{e}$, ${D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{e}^{+}{\ensuremath{ u}}_{e}$, and ${D}^{+}\ensuremath{\rightarrow}{\overline{K}}^{0}{e}^{+}{\ensuremath{ u}}_{e}$. For the total branching fractions we find $\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{e}^{+}{\ensuremath{ u}}_{e})=0.299(11)(9)%$, $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{e}^{+}{\ensuremath{ u}}_{e})=0.373(22)(13)%$, $\mathcal{B}({D}^{0}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{e}^{+}{\ensuremath{ u}}_{e})=3.56(3)(9)%$, and $\mathcal{B}({D}^{+}\ensuremath{\rightarrow}{\overline{K}}^{0}{e}^{+}{\ensuremath{ u}}_{e})=8.53(13)(23)%$, where the first error is statistical and the second systematic. In addition, form factors are studied through fits to the partial branching fractions obtained in five ${q}^{2}$ ranges. By combining our results with recent unquenched lattice calculations, we obtain $|{V}_{cd}|=0.217(9)(4)(23)$ and $|{V}_{cs}|=1.015(10)(11)(106)$, where the final error is theoretical.

Search for lepton flavor violation in upsilon decays.

Abstract: In this Letter, we describe a search for lepton flavor violation (LFV) in the bottomonium system. We search for leptonic decays Upsilon(nS)-->mutau (n=1, 2, and 3) using the data collected with the CLEO III detector. We identify the tau lepton using its leptonic decay nu_{tau}nu[over ]_{e}e and utilize multidimensional likelihood fitting with probability density function shapes measured from independent data samples. We report our estimates of 95% C.L. upper limits on LFV branching fractions of Upsilon mesons. We interpret our results in terms of the exclusion plot for the energy scale of a hypothetical new interaction versus its effective LFV coupling in the framework of effective field theory.

Comparison of DKS0 and DKL0I decay rates

Abstract: We present measurements of D{yields}K{sub S}{sup 0}{pi} and D{yields}K{sub L}{sup 0}{pi} branching fractions using 281 pb{sup -1} of {psi}(3770) data at the CLEO-c experiment. We find that B(D{sup 0}{yields}K{sub S}{sup 0}{pi}{sup 0}) is larger than B(D{sup 0}{yields}K{sub L}{sup 0}{pi}{sup 0}), with an asymmetry of R(D{sup 0})=0.108{+-}0.025{+-}0.024. For B(D{sup +}{yields}K{sub S}{sup 0}{pi}{sup +}) and B(D{sup +}{yields}K{sub L}{sup 0}{pi}{sup +}), we observe no measurable difference; the asymmetry is R(D{sup +})=0.022{+-}0.016{+-}0.018. The D{sup 0} asymmetry is consistent with the value based on the U-spin prediction A(D{sup 0}{yields}K{sup 0}{pi}{sup 0})/A(D{sup 0}{yields}K{sup 0}{pi}{sup 0})=-tan{sup 2}{theta}{sub C}, where {theta}{sub C} is the Cabibbo angle.

Evidence for Bs(*)B̄s(*) production at the Υ(5S) resonance

Abstract: We use data collected by the CLEO III detector at the Cornell Electron Storage Ring to measure the inclusive yields of D(s) mesons as B(Y(5S) --> D(s)X) = (44-7 +/- 4.2 +/- 9.9)% and B(Y(4S) --> D(s)X) = (18.1 +/- 0.5 +/- 2.8)%. From these measurements, we make a model dependent estimate of the ratio of B(s)*B(s)* to the total bb quark pair production of (16.0 +/- 2.6 +/- 5.8)% at the Y(5S) energy.

Branching fractions for transitions of ψ(2S) to J/ψ

Abstract: We report determination of branching fractions for the decays {psi}(2S){yields}h+J/{psi}, where h=any, {pi}{sup +}{pi}{sup -}, {pi}{sup 0}{pi}{sup 0}, {eta}, {pi}{sup 0}, and {gamma}{gamma} through {chi}{sub c0,1,2}. These measurements use 27M {psi}(2S) decays produced in e{sup +}e{sup -} collision data collected with the CLEO detector. The resulting branching fractions and ratios thereof improve upon previously achieved precision in all cases, and in combination with other measurements permit determination of B({chi}{sub cJ}{yields}{gamma}J/{psi}) and B({psi}(2S){yields}light hadrons)

Planck 2015 results - XIII. Cosmological parameters

Abstract: This paper presents cosmological results based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation. Our results are in very good agreement with the 2013 analysis of the Planck nominal-mission temperature data, but with increased precision. The temperature and polarization power spectra are consistent with the standard spatially-flat 6-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations (denoted “base ΛCDM” in this paper). From the Planck temperature data combined with Planck lensing, for this cosmology we find a Hubble constant, H0 = (67.8 ± 0.9) km s-1Mpc-1, a matter density parameter Ωm = 0.308 ± 0.012, and a tilted scalar spectral index with ns = 0.968 ± 0.006, consistent with the 2013 analysis. Note that in this abstract we quote 68% confidence limits on measured parameters and 95% upper limits on other parameters. We present the first results of polarization measurements with the Low Frequency Instrument at large angular scales. Combined with the Planck temperature and lensing data, these measurements give a reionization optical depth of τ = 0.066 ± 0.016, corresponding to a reionization redshift of . These results are consistent with those from WMAP polarization measurements cleaned for dust emission using 353-GHz polarization maps from the High Frequency Instrument. We find no evidence for any departure from base ΛCDM in the neutrino sector of the theory; for example, combining Planck observations with other astrophysical data we find Neff = 3.15 ± 0.23 for the effective number of relativistic degrees of freedom, consistent with the value Neff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to ∑ mν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero, with | ΩK | < 0.005. Adding a tensor component as a single-parameter extension to base ΛCDM we find an upper limit on the tensor-to-scalar ratio of r0.002< 0.11, consistent with the Planck 2013 results and consistent with the B-mode polarization constraints from a joint analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP B-mode data to our analysis leads to a tighter constraint of r0.002 < 0.09 and disfavours inflationarymodels with a V(φ) ∝ φ2 potential. The addition of Planck polarization data leads to strong constraints on deviations from a purely adiabatic spectrum of fluctuations. We find no evidence for any contribution from isocurvature perturbations or from cosmic defects. Combining Planck data with other astrophysical data, including Type Ia supernovae, the equation of state of dark energy is constrained to w = −1.006 ± 0.045, consistent with the expected value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundances for the best-fit Planck base ΛCDM cosmology are in excellent agreement with observations. We also constraints on annihilating dark matter and on possible deviations from the standard recombination history. In neither case do we find no evidence for new physics. The Planck results for base ΛCDM are in good agreement with baryon acoustic oscillation data and with the JLA sample of Type Ia supernovae. However, as in the 2013 analysis, the amplitude of the fluctuation spectrum is found to be higher than inferred from some analyses of rich cluster counts and weak gravitational lensing. We show that these tensions cannot easily be resolved with simple modifications of the base ΛCDM cosmology. Apart from these tensions, the base ΛCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

The CMS experiment at the CERN LHC

Abstract: The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1) (10(27)cm(-2)s(-1)). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4 pi solid angle. Forward sampling calorimeters extend the pseudo-rapidity coverage to high values (vertical bar eta vertical bar <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t.