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DESY-HERA. Measurement of the cross sections for production of events containing a leading neutron with at least 20% of the proton beam energy in E+ P collisions at centre-of-mass energy 300 GeV. The data come from the 1995-97 HERA running period with 27.5 GeV positrons colliding with 820 GeV protons. The data cover a wide range of Q**2 ranging from photoproduction (very low Q**2) to deep inelastic scattering (Q**2 & gt; 4 GeV**2). Fraction of events with a leading neutron at XL = 0.24.

DESY-HERA. Measurement of the proton structure function, F2, at very low X and Q**2. The range in Q**2 is from 0.045 to 0.65 GeV**2 and in X is from 6*10**-7 to 1*10**-3. The data come from collisions of 27.5 GeV positrons and 820 GeV protons with an integrated luminosity of 3.9 pb-1 taken during a six week running period in 1997 with dedicated triggers. This measurement uses the Beam Pipe Calorimeter (BPC) and Beam Pipe Tracker (BPT) to detect the scattered positrons. The BPT was installed in 1997 to compliment the BPC with precise tracking information. Measured values of F2 at Y = 0.800 as a function of Q**2.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region efficiency for simplified model with gluino pair production and decays to two quarks and chargino in SR RJR-G4.

CERN-LHC. A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing hadronic jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded in 2015 and 2016 by the ATLAS experiment in $\sqrt{s}=13\mathrm{\ Te\kern -0.1em V}$ proton--proton collisions at the Large Hadron Collider, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. The results are interpreted in the context of various models where squarks and gluinos are pair-produced and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.03$\mathrm{\ Te\kern -0.1em V}$ for a simplified model incorporating only a gluino and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.55$\mathrm{\ Te\kern -0.1em V}$ are excluded if the lightest neutralino is massless. These limits substantially extend the region of supersymmetric parameter space previously excluded by searches with the ATLAS detector. Signal region efficiency for simplified model with gluino pair production and direct decays to two quarks and neutralino in SR RJR-S3a.

CERN-LHC. This paper presents measurements of $W^\pm Z$ production in $pp$ collisions at a center-of-mass energy of 8 TeV. The gauge bosons are reconstructed using their leptonic decay modes into electrons and muons. The data were collected in 2012 by the ATLAS experiment at the Large Hadron Collider, and correspond to an integrated luminosity of 20.3 fb$^{-1}$. The measured inclusive cross section in the detector fiducial region is $\sigma_{W^\pm Z \rightarrow \ell^{'} \nu\ \ell \ell} = 35.1 \pm$ 0.9 (stat.) $\pm 0.8$ (sys.) $\pm 0.8$ (lumi.) fb, for one leptonic decay channel. In comparison, the next-to-leading-order Standard Model expectation is 30.0 $\pm$ 2.1 fb. Cross sections for $W^+Z$ and $W^-Z$ production and their ratio are presented as well as differential cross sections for several kinematic observables. Limits on anomalous triple gauge boson couplings are derived from the transverse mass spectrum of the $W^\pm Z$ system. From the analysis of events with a $W$ and a $Z$ boson associated with two or more forward jets an upper limit at 95% confidence level on the $W^\pm Z$ scattering cross section of 0.63 fb, for each leptonic decay channel, is established, while the Standard Model prediction at next-to-leading order is 0.13 fb. Limits on anomalous quartic gauge boson couplings are also extracted The cross sections are measured in a fiducial phase space reflecting the detector acceptance, defined below. Fiducial phase space definition: - $p_{\mathrm{T}}$ of electrons and muons from Z0 decays > 15 GeV - $p_{\mathrm{T}}$ of electrons and muons from the $W^{\pm}$ decays > 20 GeV - $|\eta|$ of muons and electrons < 2.5 - Leptons from the Z0 boson are separated by $\Delta R(\ell,\ell) > 0.2$ from each other - Leptons from the Z0 and W bosons are separated by $\Delta R(\ell,\ell) > 0.3$ from each other - |dilepton mass - Z0 mass| < 10 GeV - $m_{\mathrm{T}}$ of $W^{\pm}$ > 30 GeV. At particle level, the kinematics of final-state prompt electrons and muons is computed including the contributions from final-state radiated photons within a distance in the ($\eta,\phi$) plane of $\Delta R = \sqrt{(\Delta\eta)^2 + (\Delta\phi)^2} = 0.1$ around the direction of the charged lepton. These dressed leptons and the final-state neutrinos that do not originate from hadron or $\tau$ decays are associated with the $W$ and $Z$ boson decay products with an algorithmic approach, called ``resonant shape''. This algorithm is based on the value of an estimator expressing the product of the nominal line shapes of the $W$ and $Z$ resonances $P = \left| \frac{1}{ m^2_{(\ell^+,\ell^-)} - \left(m_Z^{\textrm{PDG}}\right)^2 + i \; \Gamma_Z^{\textrm{PDG}} \; m_Z^{\textrm{PDG}} } \right|^2 \times \; \left| \frac {1} { m^2_{(\ell',\nu_{\ell'})} - \left(m_W^{\textrm{PDG}}\right)^2 + i \; \Gamma_W^{\textrm{PDG}} \; m_W^{\textrm{PDG}} } \right|^2$ where $m_Z^{\textrm{PDG}}$ ($m_W^{\textrm{PDG}}$) and $\Gamma_Z^{\textrm{PDG}}$ ($\Gamma_W^{\textrm{PDG}}$) are the world average mass and total width of the $Z$ ($W$) boson, respectively, as reported by the Particle Data Group~\cite{Agashe:2014kda}. The input to the estimator is the invariant mass $m$ of all possible pairs ($\ell^+,\ell^-$) and ($\ell',\nu_{\ell'}$) satisfying the fiducial selection requirements defined in the next paragraph. The final choice of which leptons are assigned to the $W$ or $Z$ bosons corresponds to the configuration exhibiting the highest value of the estimator. The inclusive cross section is also extrapolated to the total phase space and all W and Z boson decay modes. This result is model-dependent and includes phase space that was not experimentally accessible, so it should be used with caution. Whenever possible, the fiducial cross sections should be used instead, since they are only minimally model-dependent. Fiducial phase space for VBS measurement: additional criteria to the above Fiducial phase space definition - at least 2 jets - $p_{\mathrm{T}}$ of jets > 30 GeV - $|\eta|$ of jets < 4.5 - invariant mass of the 2 leading jets > 500 GeV - leptons and jets separated by $\Delta R(\ell,jet) > 0.3$ where jets are particle level jets with anti-kt R=0.4. Fiducial phase space for aQGC measurement: additional criteria to the above VBS phase space definition - difference in azimuthal angle between W and Z bosons directions $|\Delta \phi(W,Z)| > 2$ - scalar sum of the transverse momenta of the three charged leptons associated with W and Z bosons $\sum |p_{\mathrm{T}}^{\ell}| > 250$ GeV. Measured fiducial cross section in all $\ell'^\pm \nu \ell^+ \ell'^-$ channels combined, where $\ell, \ell' = e, \mu$. The first systematic uncertainty is the combined systematic uncertainty excluding theory and luminosity uncertainties, the second is the luminosity uncertainty. The last bin is a cross section for all events above the lower end of the bin.

Upper limits at 90% CL for the elements of the extended neutrino mixing matrix |Ue4|^2 and |Umu4|^2 depending on the assumed heavy neutral lepton mass. Upper limits on |U_mu4|^2 vs assumed neutrino mass [MeV].

We measure the extent to which skilled immigrants increase innovation in the United States. The 2003 National Survey of College Graduates shows that immigrants patent at double the native rate, due to their disproportionately holding science and engineering degrees. Using a 1940-2000 state panel, we show that a 1 percentage point increase in immigrant college graduates' population share increases patents per capita by 9-18 percent. Our instrument for the change in the skilled immigrant share is based on the 1940 distribution across states of immigrants from various source regions and the subsequent national increase in skilled immigration from these regions. (JEL J24, J61, O31, O33)

This paper presents results of searches for electroweak production of supersymmetric particles in models with compressed mass spectra. The searches use 139/fb of sqrt(s) = 13 TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider. Events with missing transverse momentum and two same-flavor, oppositely charged, low transverse momentum leptons are selected, and are further categorized by the presence of hadronic activity from initial-state radiation or a topology compatible with vector-boson fusion processes. The data are found to be consistent with predictions from the Standard Model. The results are interpreted using simplified models of R-parity-conserving supersymmetry in which the lightest supersymmetric partner is a neutralino with a mass similar to the lightest chargino, the second-to-lightest neutralino or the slepton. Lower limits on the masses of charginos in different simplified models range from 193 GeV to 240 GeV for moderate mass splittings, and extend down to mass splittings of 1.5 GeV to 2.4 GeV at the LEP chargino bounds (92.4 GeV). Similar lower limits on degenerate light-flavor sleptons extend up to masses of 251 GeV and down to mass splittings of 550 MeV. Constraints on vector-boson fusion production of electroweak SUSY states are also presented. Acceptance (note the $z$-axis is in units of $10^{-4}$) for the N2N1 VBF higgsino process in the SR-VBF-high region. Truth dilepton invariant mass is constrained to be within the range [1,40] GeV.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures. Related Article: Marie-HA A{C}lA A{umlaut}ne Tremblay, Allyson Boyington, Sergei Rigin, Jie Jiang, John Bacsa, Khaled Al Kurdi, Victor N. Khrustalev, Ruth Pachter, Tatiana V. Timofeeva, Nathan Jui, Stephen Barlow, Seth R. Marder|2022|Chem.Mater.|34|935|doi:10.1021/acs.chemmater.1c01642

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures. Related Article: Alex J. Veinot, Angela D. K. Todd, and Jason D. Masuda|2017|Angew.Chem.,Int.Ed.|56|11615|doi:10.1002/anie.201706398