52,744 research outputs found
D. Allan Bromley Letter to Samuel Skinner
A letter to Samuel K. Skinner, Secretary of Transportation, from D. Allan Bromley, Director of the Office of Science and Technology Policy (OSTP). Bromley thanks Skinner for agreeing to meet with the President's Council of Advisors on Science and Technology (PCAST) and offers him some background information on the meeting and PCAST
Writing and the rights of reality: usurpation and potentiality in Derrida, Plato, Nietzsche, and Beckett
The thesis critically evaluates Jacques Derrida's conferral of the rights of reality on writing, focussing on his theory of an arche-text in light of the speculative nature of this theory. The theory is initially considered in the context of Derrida's elucidation of the usurpatory status of writing within the Platonic and Nietzschean texts. This consideration reveals an admission of writing's usurpatory status by both writers while at the same time demonstrating their awareness of the intrinsically speculative nature of this view, the significance of writing lying in its ability to exteriorise the radically indeterminate status of consciousness m relation to reality rather than its ability to displace consciousness or reality The analyses, therefore, not only bring the Derridean hypothesis of a repressive or phonocentric metaphysical episteme into question but also exhibit the historical and philosophical role of potentiality in relation to writing, writing's ultimate significance lying in its capacity to exteriorise our existence as a mode of potentiality. Accordingly, in the second half of the thesis the Derridean theory of writing is countered with a specifically Aristotelian theory of the text as it is exhibited in the prose of Samuel Beckett, an author whose significance lies in his close alignment with Derridean theory within contemporary criticism. It is demonstrated that this identification has obviated an awareness of the significance of potentiality within the Beckettian text, his work consequently being appraised in the previously neglected context of Aristotelian metaphysics
Amplitude analysis of D-0 -> K- pi(+) pi(+) pi(-)
Kolcu, Onur Buğra (Arel Author)Kolcu, Onur Buğra (Arel Author)We present an amplitude analysis of the decay D-0 -> K- pi(+)pi(+)pi(-) based on a data sample of 2.93 fb(-1) acquired by the BESIII detector at the psi(3770) resonance. With a nearly background free sample of about 16000 events, we investigate the substructure of the decay and determine the relative fractions and the phases among the different intermediate processes. Our amplitude model includes the two-body decays D-0 -> (K) over bar*(0)rho(0), D-0 -> K- a(1)(+) (1260) and D-0 -> K-1(-)(1270)pi(+), the three-body decays D-0 -> K-1(-)*(0)pi(+)pi(-) and D-0 -> K- pi(+)rho(0), as well as the four-body nonresonant decay D-0 -> K- pi(+)pi(+)pi(-). The dominant intermediate process is D-0 -> K(-)a(1)(+)(1260)accounting for a fit fraction of 54.6%.We present an amplitude analysis of the decay D-0 -> K- pi(+)pi(+)pi(-) based on a data sample of 2.93 fb(-1) acquired by the BESIII detector at the psi(3770) resonance. With a nearly background free sample of about 16000 events, we investigate the substructure of the decay and determine the relative fractions and the phases among the different intermediate processes. Our amplitude model includes the two-body decays D-0 -> (K) over bar*(0)rho(0), D-0 -> K- a(1)(+) (1260) and D-0 -> K-1(-)(1270)pi(+), the three-body decays D-0 -> K-1(-)*(0)pi(+)pi(-) and D-0 -> K- pi(+)rho(0), as well as the four-body nonresonant decay D-0 -> K- pi(+)pi(+)pi(-). The dominant intermediate process is D-0 -> K(-)a(1)(+)(1260)accounting for a fit fraction of 54.6%
Measurement of CP asymmetry in D-0 -> K- K+ and D-0 -> pi(-) pi(+) decays
Time-integrated CP asymmetries in D 0 decays to the final states K - K + and π - π + are measured using proton-proton collisions corresponding to 3fb-1 of integrated luminosity collected at centre-of-mass energies of 7 TeV and 8 TeV. The D 0 mesons are produced in semileptonic b-hadron decays, where the charge of the accompanying muon is used to determine the initial flavour of the charm meson. The difference in CP asymmetries between the two final states is measured to be Δ ACP = ACP (K- K +) ACP (π- π+) = (+ 0.14 ± 0.16 (stat) ± 0.08 (syst)) %. A measurement of A CP (K - K +) is obtained assuming negligible CP violation in charm mixing and in Cabibbo-favoured D decays. It is found to be ACP (K- K+) = (- 0.06 ± 0.15 (stat) ± 0.10 (syst)) %, where the correlation coefficient between ΔA CP and A CP (K - K +) is ρ = 0.28. By combining these results, the CP asymmetry in the D 0 → π - π + channel is A CP (π - π +) = (-0.20 ± 0.19 (stat) ± 0.10 (syst))%. [Figure not available: see fulltext.] © 2014 The Author(s)
Measurement of D-0-(D)over-bar(0) mixing using the ratio of lifetimes for the decays D-0 -> K-pi(+) and K+K-
We measure the rate of D-0-(D) over bar0 mixing with the observable y(CP) = (tau(K pi)/tau(KK)) - 1, where tau(KK) and tau(K pi) are, respectively, the mean lifetimes of CP-even D-0 -> K+K- and CP-mixed D-0 -> K-pi(+) decays, using a data sample of 384 fb(-1) collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B Factory. From a sample of D-0 and (D) over bar0 decays where the initial flavor of the decaying meson is not determined, we obtain y(CP) = [1.12 +/- 0.26(stat) +/- 0.22(syst)]%, which excludes the no-mixing hypothesis at 3.3 sigma, including both statistical and systematic uncertainties. This result is in good agreement with a previous BABAR measurement of y(CP) obtained from a sample of D*(+) -> D-0 pi(+) events, where the D-0 rho decays to K-pi(+), K+K-, and pi(+)pi(-), which is disjoint with the untagged D-0 events used here. Combining the two results taking into account statistical and systematic uncertainties, where the systematic uncertainties are assumed to be 100% correlated, we find y(CP) = [1.16 +/- 0.22(stat) +/- 0.18(syst)]%, which excludes the no-mixing hypothesis at 4.1 sigma
First observation of Λb0 → ςc (∗)++ D (∗)-K- decays
The four decays, Λb0→ςc(∗)++D(∗)-K-, are observed for the first time using proton-proton collision data collected with the LHCb detector at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6 fb-1. By considering the Λb0→Λc+D¯0K- decay as reference channel, the following branching fraction ratios are measured to be B(Λb0→ςc++D-K-)B(Λb0→Λc+D¯0K-)=0.282±0.016±0.016±0.005, B(Λb0→ςc∗++D-K-)B(Λb0→ςc++D-K-)=0.460±0.052±0.028, B(Λb0→ςc++D∗-K-)B(Λb0→ςc++D-K-)=2.261±0.202±0.129±0.046, B(Λb0→ςc∗++D∗-K-)B(Λb0→ςc++D-K-)=0.896±0.137±0.066±0.018, where the first uncertainties are statistical, the second are systematic, and the third are due to uncertainties in the branching fractions of intermediate particle decays. These initial observations mark the beginning of pentaquark searches in these modes, with more datasets to become available following the LHCb upgrade. © 2024 CERN, for the LHCb Collaboration. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3
Study of the decays D-s(+ )-> (KSK+)-K-0 and (KLK+)-K-0
Kolcu, Onur Buğra (Arel Author)Using an e(+)e(-) annihilation data sample corresponding to an integrated luminosity of 3.19 fb(-1) and collected at a center-of-mass energy root s = 4.178 GeV with the BESIII detector, we measure the absolute branching fractions B(D-s(+) -> (KSK+)-K-0) = (1.425 +/- 0.038(stat). +/- 0.031(syst).)% and B(D-s(+) -> (KLK+)-K-0) = (1.485 +/- 0.039(stat). +/- 0.046(syst).)%. The branching fraction of D-s(+) -> (KSK+)-K-0 is compatible with the world average and that of D-s(+) -> (KLK+)-K-0 is measured for the first time. We present the first measurement of the K-S(0)-K-L(0) asymmetry in the decays D-s(+) -> (KS,LK+)-K-0, and R((Ds+KS,LK+)-K-0) = B(D-s(+) -> (KSK+)-K-0)-B(D-s(+) -> (KLK+)-K-0)/B(D-s(+) -> (KSK+)-K-0)+B(D-s(+) -> (KLK+)-K-0) = (-2.1 +/- 1.9(stat). +/- 1.6(syst).)%. In addition, we measure the direct CP asymmetries A(CP) (D-s(+/-) -> (KSK +/-)-K-0). (0.6 +/- 2.8(stat). +/- 0.6(syst).)% and A(CP)(D-s(+/-) -> (KLK +/-)-K-0 ) = (-1.1 +/- 2.6(stat). +/- 0.6(syst))
Mudd, Samuel A., October 21, 2002 [Interview]
Professor of Psychology Samuel A. Mudd was interviewed on October 21, 2002, by Michael Birkner about his childhood during the Great Depression; his mother's battle with schizophrenia; memories of FDR and World War II; serving in the peacetime Air Force; and being a student at Gettysburg College.Wolfe, Charles R.; Dunkelberger, Harold A.; Shaffer, W. Frederick; Sundermyer, William K.; Ahrens, Frederick C.; Glatfelter, Charles H.; Hanson, Carl Arnold; Shand, John D.; Smoke, Kenneth L.; Freed, Edwin D.; Bream, Henry T.; D'Agostino, RobertGreat Depression; World War II; Walter C. Langsam Years; Willard S. Paul Year
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
The ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Constraints on the CKM angle gamma in B-0 ->(D)over bar(0)K(*0) and B-0 ->(DK*0)-K-0 from a Dalitz analysis of D-0 and (D)over bar(0) decays to K-S pi(+)pi(-)
We present constraints on the angle gamma of the unitarity triangle with a Dalitz analysis of neutral D decays to K-S pi(+)pi(-) from the processes B-0 ->(D)over bar(0)K(*0) ((B)over bar(0)-> D-0(K)over bar (*0)) and B-0 ->(DK*0)-K-0 ((B)over bar(0)->(D)over bar(0)(K)over bar(*0)) with K-*0 -> K+pi(-) ((K)over bar(*0)-> K-pi(+)). Using a sample of 371x10(6) B(B)over bar pairs collected with the BABAR detector at PEP-II, we constrain the angle gamma as a function of r(S), the magnitude of the average ratio between b -> u and b -> c amplitudes
- …
