Now showing items 491-510 of 893

• #### Observation of a diffractive contribution to dijet production in proton-proton collisions at √s=7  TeV ﻿

(2013)
The cross section for dijet production in proton-proton collisions at √s=7  TeV is presented as a function of ξ˜, a variable that approximates the fractional momentum loss of the scattered proton in single-diffractive ...
• #### Observation of a Helical Luttinger Liquid in InAs/GaSb Quantum Spin Hall Edges ﻿

(2015)
We report on the observation of a helical Luttinger liquid in the edge of an InAs/GaSb quantum spin Hall insulator, which shows characteristic suppression of conductance at low temperature and low bias voltage. Moreover, ...
• #### Observation of a narrow mass state decaying into Υ(1S)+γ in pp¯ collisions at √s=1.96  TeV ﻿

(2012)
Using data corresponding to an integrated luminosity of 1.3  fb−1, we observe a narrow mass state decaying into Υ(1S)+γ, where the Υ(1S) meson is detected by its decay into a pair of oppositely charged muons, and the photon ...
• #### Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC ﻿

(2012)
Results are presented from searches for the standard model Higgs boson in proton–proton collisions at √s=7 and 8 TeV in the Compact Muon Solenoid experiment at the LHC, using data samples corresponding to integrated ...
• #### Observation of a new boson with mass near 125 GeV in pp collisions at √s=7 and 8 TeV ﻿

(2013)
A detailed description is reported of the analysis used by the CMS Collaboration in the search for the standard model Higgs boson in pp collisions at the LHC, which led to the observation of a new boson. The data sample ...
• #### Observation of a New Ξb Baryon ﻿

(2012)
The observation of a new b baryon via its strong decay into Ξ−bπ+ (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at √s=7  TeV collected by the CMS experiment at the LHC, corresponding ...
• #### Observation of a peaking structure in the J/ψϕ mass spectrum from B±→ J/ψϕK± decays ﻿

(2014)
A peaking structure in the J/ψϕ mass spectrum near threshold is observed in B±→J/ψϕK± decays, produced in pp collisions at √s=7 TeV collected with the CMS detector at the LHC. The data sample, selected on the basis of the ...
• #### Observation of an Energy-Dependent Difference in Elliptic Flow between Particles and Antiparticles in Relativistic Heavy Ion Collisions ﻿

(2013)
Elliptic flow (v2) values for identified particles at midrapidity in Au+Au collisions, measured by the STAR experiment in the beam energy scan at RHIC at √sNN=7.7–62.4  GeV, are presented. A beam-energy-dependent difference ...
• #### Observation of antiferromagnetic correlations in the Hubbard model with ultracold atoms ﻿

(2015)
Ultracold atoms in optical lattices have great potential to contribute to a better understanding of some of the most important issues in many-body physics, such as high-temperature superconductivity[1]. The Hubbard model—a ...
• #### Observation of D0 Meson Nuclear Modifications in Au+Au Collisions at √sNN=200  GeV ﻿

(2014)
We report the first measurement of charmed-hadron (D0) production via the hadronic decay channel (D0→K−+π+) in Au+Au collisions at √sNN=200  GeV with the STAR experiment. The charm production cross section per nucleon-nucleon ...
• #### Observation of Edge Transport in the Disordered Regime of Topologically Insulating InAs/GaSb Quantum Wells ﻿

(2014-01)
We observe edge transport in the topologically insulating InAs=GaSb system in the disordered regime. Using asymmetric current paths we show that conduction occurs exclusively along the device edge, exhibiting a large Hall ...
• #### Observation of Forbidden Exciton Transitions Mediated by Coulomb Interactions in Photoexcited Semiconductor Quantum Wells ﻿

(2013)
We use terahertz pulses to induce resonant transitions between the eigenstates of optically generated exciton populations in a high-quality semiconductor quantum well sample. Monitoring the excitonic photoluminescence, we ...
• #### Observation of long-range, near-side angular correlations in pPb collisions at the LHC ﻿

(2013)
Results on two-particle angular correlations for charged particles emitted in pPb collisions at a nucleon–nucleon center-of-mass energy of 5.02 TeV are presented. The analysis uses two million collisions collected with the ...
• #### Observation of Quantum Jumps in a Single Atom ﻿

(1986)
We detect the radiatively driven electric quadrupole transition to the metastable D522 state in a single, laser-cooled Hg II ion by monitoring the abrupt cessation of the fluorescence signal from the laser-excited S122→P122 ...
• #### Observation of Sequential Υ Suppression in PbPb Collisions ﻿

(2012)
The suppression of the individual Υ(nS) states in PbPb collisions with respect to their yields in pp data has been measured. The PbPb and pp data sets used in the analysis correspond to integrated luminosities of 150  μb−1 ...
• #### Observation of the Associated Production of a Single Top Quark and a W Boson in pp Collisions at √s=8  TeV ﻿

(2014)
The first observation of the associated production of a single top quark and a W boson is presented. The analysis is based on a data set corresponding to an integrated luminosity of 12.2  fb−1 of proton-proton collisions ...
• #### Observation of the diphoton decay of the Higgs boson and measurement of its properties ﻿

(2014)
Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton ...
• #### Observation of the rare Bs0 →µ+µ− decay from the combined analysis of CMS and LHCb data ﻿

(2015)
The standard model of particle physics describes the fundamental particles and their interactions via the strong, electromagnetic and weak forces. It provides precise predictions for measurable quantities that can be tested ...
• #### Observation of velocity-tuned multiphoton "Doppleron" resonances in laser-cooled atoms ﻿

(1990)
An atomic beam of Li was transversely cooled using an intense standing-wave radiation field. A dramatic change in the transverse velocity distribution was observed. Structure in the resulting velocity distribution was found ...
• #### Observation of Z decays to four leptons with the CMS detector at the LHC ﻿

(2012)
The first observation of the Z boson decaying to four leptons in proton-proton collisions is presented. The analyzed data set corresponds to an integrated luminosity of 5.02 fb−1 at √s=7 TeV collected by the CMS detector ...