55 research outputs found
Author Correction: COVID-19 vaccine guidance for patients with cancer participating in oncology clinical trials
No full textIn the original version of this Perspective, the name of the author Giuseppe Curigliano was incorrectly written as Guiseppe Curigiliano. The affiliations have been corrected in the HTML and PDF versions of the manuscrip
Search for direct CP violation in D0→h−h+ modes using semileptonic B decays
No full textA search for direct CP violation in D0 → h-h+ (where h = K or π) is presented using data corresponding to an integrated luminosity of 1.0 fb-1 collected in 2011 by LHCb in pp collisions at a centre-of-mass energy of 7 TeV. The analysis uses D0 mesons produced in inclusive semileptonic b-hadron decays to the D0μX final state, where the charge of the accompanying muon is used to tag the flavour of the D0 meson. The difference in the CP-violating asymmetries between the two decay channels is measured to be ΔACP = ACP(K-K+) - ACP(π-π+) = (0.49± 0.30 (stat) ± 0.14 (syst))%
Measurement of the effective B0s→K+K− lifetime
No full textA measurement of the effective lifetime is presented using approximately 37 pb−1 of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from processes beyond the Standard Model in the meson system and is determined by two complementary approaches as
τKK=1.440±0.096 (stat)±0.008 (syst)±0.003 (model) ps
Measurement of the branching fraction
No full textThe B
0
s
→ J/ψK
0
S
branching fraction is measured in a data sample corresponding to 0.41 fb−1
of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to
the penguin contributions affecting the sin 2β measurement from B
0
→ J/ψK
0
S
. The time-integrated
branching fraction is measured to be B(B
0
s
→ J/ψK
0
S
) = (1.83±0.28)×10−5
. This is the most precise
measurement to date
905 How to prioritise patients and safely resume elective surgery during the Covid-19 pandemic
No full textTin Oxide Electron‐Selective Layers for Efficient, Stable, and Scalable Perovskite Solar Cells
No full textPerovskite solar cells (PSCs) have become a promising photovoltaic (PV) technology, where the evolution of the electron-selective layers (ESLs), an integral part of any PV device, has played a distinctive role to their progress. To date, the mesoporous titanium dioxide (TiO2)/compact TiO2 stack has been among the most used ESLs in state-of-the-art PSCs. However, this material requires high-temperature sintering and may induce hysteresis under operational conditions, raising concerns about its use toward commercialization. Recently, tin oxide (SnO2) has emerged as an attractive alternative ESL, thanks to its wide bandgap, high optical transmission, high carrier mobility, suitable band alignment with perovskites, and decent chemical stability. Additionally, its low-temperature processability enables compatibility with temperature-sensitive substrates, and thus flexible devices and tandem solar cells. Here, the notable developments of SnO2 as a perovskite-relevant ESL are reviewed with emphasis placed on the various fabrication methods and interfacial passivation routes toward champion solar cells with high stability. Further, a techno-economic analysis of SnO2 materials for large-scale deployment, together with a processing-toxicology assessment, is presented. Finally, a perspective on how SnO2 materials can be instrumental in successful large-scale module and perovskite-based tandem solar cell manufacturing is provided.This work was supported by the Scientific and Technical Research Council of Turkey (TUBITAK, Grant No. 119M149) and by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award Nos. OSR-2019-CARF/CCF-3097 and OSR-2019-CRG-4093.Altinkaya, C (corresponding author), Ankara Yildirim Beyazit Univ, Fac Engn & Nat Sci, Dept Energy Syst Engn, TR-06010 Ankara, Turkey.
Aydin, E; De Wolf, S (corresponding author), King Abdullah Univ Sci & Technol KAUST, Phys Sci & Engn Div PSE, KAUST Solar Ctr KSC, Thuwal 239556900, Saudi Arabia.
[email protected]; [email protected]; [email protected]
A study of CP violation in B±→DK±B±→DK± and B±→Dπ±B±→Dπ± decays with D→KS0K±π∓ final states
No full textA first study of CP violation in the decay modes B± → [K0S K ±π∓]Dh± and B± → [K0S K ∓π±]Dh±, where h labels a K or π meson and D labels a D0 or D0 meson, is performed. The analysis uses the LHCb data set collected in pp collisions, corresponding to an integrated luminosity of 3 fb−1. The analysis is sensitive to the CP-violating CKM phase γ through seven observables: one charge asymmetry in each of the four modes and three ratios of the charge-integrated yields. The results are consistent with measurements of γ using other decay modes
Prompt charm production in pp collisions at √<span style="text-decoration:overline">s</span>=7 TeV
No full textCharm production at the LHC in pp collisions at s√=7 TeV is studied with the LHCb detector. The decays D0→K−π+, D+→K−π+π+, D⁎+→D0(K−π+)π+, D+s→ϕ(K−K+)π+, Λ+c→pK−π+, and their charge conjugates are analysed in a data set corresponding to an integrated luminosity of 15 nb−1. Differential cross-sections dσ/dpT are measured for prompt production of the five charmed hadron species in bins of transverse momentum and rapidity in the region 0<pT<8 GeV/c and 2.0<y<4.5. Theoretical predictions are compared to the measured differential cross-sections. The integrated cross-sections of the charm hadrons are computed in the above pT-y range, and their ratios are reported. A combination of the five integrated cross-section measurements gives
σ(cc¯)pT<8 GeV/c,2.0<y<4.5=1419±12(stat)±116(syst)±65(frag) μb,
where the uncertainties are statistical, systematic, and due to the fragmentation functions
Measurement of the cross-section ratio σ(χc2)/σ(χc1) for prompt χc production at √s=7 TeV
No full textThe prompt production of the charmonium χc1 and χc2 mesons has been studied in proton–proton collisions at the Large Hadron Collider at a centre-of-mass energy of . The χc mesons are identified through their decays χc→J/ψγ with J/ψ→μ+μ− using 36 pb−1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for the two χc spin states, σ(χc2)/σ(χc1), has been determined as a function of the J/ψ transverse momentum, , in the range from 2 to 15 GeV/c. The results are in agreement with the next-to-leading order non-relativistic QCD model at high and lie consistently above the pure leading-order colour-singlet prediction
First observation of the decay Bs0→K*0K*0
No full textThe first observation of the decay B0s→K∗0K∗0 is reported using 35 pb−1 of data collected by LHCb in proton–proton collisions at a centre-of-mass energy of 7 TeV. A total of 49.8±7.5 B0s→(K+π−)(K−π+) events are observed within ±50 MeV/c2 of the B0s mass and 746 MeV/c2 < mKπ < 1046 MeV/c2, mostly coming from a resonant B0s→K∗0K∗0 signal. The branching fraction and the CP-averaged K∗0 longitudinal polarization fraction are measured to be B(B0s→K∗0K∗0)=(2.81±0.46(stat.)±0.45(syst.)±0.34(fs/ fd))×10−5 and fL =0.31±0.12(stat.)±0.04(syst.)
- …
