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Mass measurements continue to provide invaluable information for elucidating nuclear structure and scenarios of astrophysical interest. The transition region between the $Z = 20$ and $28$ proton shell closures is particularly interesting due to the onset and evolution of nuclear deformation as nuclei become more neutron rich. This provides a critical testing ground for emerging ab-initio nuclear structure models. Here, we present high-precision mass measurements of neutron-rich chromium isotopes using the sensitive electrostatic Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility. Our high-precision mass measurements of $^{59, 61-63}$Cr confirm previous results, and the improved precision in measurements of $^{64-65}$Cr refine the mass surface beyond N=40. With the ab initio in-medium similarity renormalization group, we examine the trends in collectivity in chromium isotopes and give a complete picture of the N=40 island of inversion from calcium to nickel. Mass measurements continue to provide invaluable information for elucidating nuclear structure and scenarios of astrophysical interest. The transition region between the Z=20 and 28 proton shell closures is particularly interesting due to the onset and evolution of nuclear deformation as nuclei become more neutron-rich. This provides a critical testing ground for emerging ab-initio nuclear structure models. Here, we present high-precision mass measurements of neutron-rich chromium isotopes using the sensitive electrostatic Multiple-Reflection Time-Of-Flight Mass Spectrometer (MR-TOF-MS) at TRIUMF's Ion Trap for Atomic and Nuclear Science (TITAN) facility. Our high-precision mass measurements of 59,61−63Cr confirm previous results, and the improved precision in measurements of 64−65Cr refine the mass surface beyond N=40. With the ab initio in-medium similarity renormalization group, we examine the trends in collectivity in chromium isotopes and give a complete picture of the N=40 island of inversion from calcium to nickel.

Run card for the benchmark signal used for cutflow in Table 10 CERN-LHC. ATLAS. What else belongs here?

Almost all research output includes tables, diagrams, photographs and even sketches, and papers within HCI typically take advantage of including these figures in their files. However the space given to non-diagrammatical or tabular figures is often small, even in papers that primarily concern themselves with visual output. The reason for this might be the publishing models employed in most proceedings and journals: Despite moving to a digital format which is unhindered by page count or physical cost, there remains a somewhat arbitrary limitation on page count. Recent moves by ACM SIGCHI and others to remove references from the maximum page count suggest that there is movement on this, however images remain firmly within the limits of the text. We propose that images should be celebrated – not penalised – and call for not only the adoption of the Pictorials format in CHI, but for images to be removed from page counts in order to encourage greater transparency of process in HCI research.

The Optical Spectrograph and Infra-Red Imager System (OSIRIS) and the Atmospheric Chemistry Experiment (ACE) have been taking measurements from space since 2001 and 2003, respectively. This paper presents intercomparisons between ozone and NO2 measured by the ACE and OSIRIS satellite instruments and by ground-based instruments at the Polar Environment Atmospheric Research Laboratory (PEARL), which is located at Eureka, Canada (80° N, 86° W) and is operated by the Canadian Network for the Detection of Atmospheric Change (CANDAC). The ground-based instruments included in this study are four zenith-sky differential optical absorption spectroscopy (DOAS) instruments, one Bruker Fourier transform infrared spectrometer (FTIR) and four Brewer spectrophotometers. Ozone total columns measured by the DOAS instruments were retrieved using new Network for the Detection of Atmospheric Composition Change (NDACC) guidelines and agree to within 3.2%. The DOAS ozone columns agree with the Brewer spectrophotometers with mean relative differences that are smaller than 1.5%. This suggests that for these instruments the new NDACC data guidelines were successful in producing a homogenous and accurate ozone dataset at 80° N. Satellite 14–52 km ozone and 17–40 km NO2 partial columns within 500 km of PEARL were calculated for ACE-FTS Version 2.2 (v2.2) plus updates, ACE-FTS v3.0, ACE-MAESTRO (Measurements of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) v1.2 and OSIRIS SaskMART v5.0x ozone and Optimal Estimation v3.0 NO2 data products. The new ACE-FTS v3.0 and the validated ACE-FTS v2.2 partial columns are nearly identical, with mean relative differences of 0.0 ± 0.2% and −0.2 ± 0.1% for v2.2 minus v3.0 ozone and NO2, respectively. Ozone columns were constructed from 14–52 km satellite and 0–14 km ozonesonde partial columns and compared with the ground-based total column measurements. The satellite-plus-sonde measurements agree with the ground-based ozone total columns with mean relative differences of 0.1–7.3%. For NO2, partial columns from 17 km upward were scaled to noon using a photochemical model. Mean relative differences between OSIRIS, ACE-FTS and ground-based NO2 measurements do not exceed 20%. ACE-MAESTRO measures more NO2 than the other instruments, with mean relative differences of 25–52%. Seasonal variation in the differences between NO2 partial columns is observed, suggesting that there are systematic errors in the measurements and/or the photochemical model corrections. For ozone spring-time measurements, additional coincidence criteria based on stratospheric temperature and the location of the polar vortex were found to improve agreement between some of the instruments. For ACE-FTS v2.2 minus Bruker FTIR, the 2007–2009 spring-time mean relative difference improved from −5.0 ± 0.4% to −3.1 ± 0.8% with the dynamical selection criteria. This was the largest improvement, likely because both instruments measure direct sunlight and therefore have well-characterized lines-of-sight compared with scattered sunlight measurements. For NO2, the addition of a ±1° latitude coincidence criterion improved spring-time intercomparison results, likely due to the sharp latitudinal gradient of NO2 during polar sunrise. The differences between satellite and ground-based measurements do not show any obvious trends over the missions, indicating that both the ACE and OSIRIS instruments continue to perform well.

A search for the direct production of the supersymmetric partners of tau leptons (staus) in final states with two hadronically decaying $\tau$ leptons is presented. The analysis uses a dataset of $pp$ collisions corresponding to an integrated luminosity of 139 $fb^{-1}$, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. No significant deviation from the expected Standard Model background is observed. Limits are derived in scenarios of direct production of stau pairs with each stau decaying into the stable lightest neutralino and one $\tau$-lepton in simplified models where the two stau mass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidence level for a massless lightest neutralino. Truth code to compute acceptance for all signal regions (including separate stau final states) using the SimpleAnalysis framework

Exclusive production of dielectron pairs, γγ → e$^{+}$e$^{−}$, is studied using $ {\mathcal{L}}_{\textrm{int}} $ = 1.72 nb$^{−1}$ of data from ultraperipheral collisions of lead nuclei at $ \sqrt{s_{\textrm{NN}}} $ = 5.02 TeV recorded by the ATLAS detector at the LHC. The process of interest proceeds via photon–photon interactions in the strong electromagnetic fields of relativistic lead nuclei. Dielectron production is measured in the fiducial region defined by following requirements: electron transverse momentum $ {p}_{\textrm{T}}^e $> 2.5 GeV, absolute electron pseudorapidity |η$^{e}$| 5 GeV, and dielectron transverse momentum $ {p}_{\textrm{T}}^{ee} $< 2 GeV. Differential cross-sections are measured as a function of m$_{ee}$, average $ {p}_{\textrm{T}}^e $, absolute dielectron rapidity |y$_{ee}$|, and scattering angle in the dielectron rest frame, |cos θ$^{*}$|, in the inclusive sample, and also with a requirement of no activity in the forward direction. The total integrated fiducial cross-section is measured to be $ 215\pm 1{\left(\textrm{stat}.\right)}_{-20}^{+23}\left(\textrm{syst}.\right)\pm 4\left(\textrm{lumi}.\right) $μb. Within experimental uncertainties the measured integrated cross-section is in good agreement with the QED predictions from the Monte Carlo programs Starlight and SuperChic, confirming the broad features of the initial photon fluxes. The differential cross-sections show systematic differences from these predictions which are more pronounced at high |y$_{ee}$| and |cos θ$^{*}$| values.[graphic not available: see fulltext] Exclusive production of dielectron pairs, $\gamma\gamma\rightarrow e^+e^-$, is studied using $\mathcal{L}_\mathrm{int}=1.72\; \mathrm{nb^{-1}}$ of data from ultraperipheral collisions of lead nuclei at $\sqrt{s_{_{\text{NN}}}} = 5.02$ TeV recorded by the ATLAS detector at the LHC. The process of interest proceeds via photon-photon interaction in the strong electromagnetic fields of relativistic lead nuclei. Dielectron production is measured in the fiducial region defined by following requirements: electron transverse momentum, $p_{\textrm{T}}^{e} > 2.5$ GeV, absolute electron pseudorapidity, $|\eta^{e}| 5$ GeV, and transverse momentum of the dielecton pair, $p_{\textrm{T}}^{ee} < 2$ GeV. Differential cross-sections are measured as a function of $m_{ee}$, average $p_{\textrm{T}}^{e}$, absolute rapidity of the dielectron system, $|y_{ee}|$, and scattering angle in the dielectron rest frame, $|\cos\theta^*|$ in the inclusive sample, and also under the requirement of no activity in the forward direction. The total integrated fiducial cross-section is measured to be $215 \pm 1 \text{(stat.)} ^{+23}_{-20} \text{(syst.)} \pm 4 \text{(lumi.)}\; \mu$b. Within experimental uncertainties the measured integrated cross-section is in good agreement with the QED predictions from the Monte Carlo programs Starlight and SuperChic, confirming the broad features of the initial photon fluxes. The differential cross-sections show systematic differences with these predictions which are more pronounced at high $|y_{ee}|$ and $|\cos\theta^*|$ values. Exclusive production of dielectron pairs, $\gamma\gamma\rightarrow e^+e^-$, is studied using $\mathcal{L}_\mathrm{int}=1.72 \mathrm{nb^{-1}}$ of data from ultraperipheral collisions of lead nuclei at $\sqrt{s_{_{\text{NN}}}} = 5.02$ TeV recorded by the ATLAS detector at the LHC. The process of interest proceeds via photon-photon interaction in the strong electromagnetic fields of relativistic lead nuclei. Dielectron production is measured in the fiducial region defined by following requirements: electron transverse momentum, $p_{\textrm{T}}^{e} > 2.5$ GeV, absolute electron pseudorapidity, $|\eta^{e}| 5$ GeV, and transverse momentum of the dielecton pair, $p_{\textrm{T}}^{ee} < 2$ GeV. Differential cross-sections are measured as a function of $m_{ee}$, average $p_{\textrm{T}}^{e}$), absolute rapidity of the dielectron system, $|y_{ee}|$, and scattering angle in the dielectron rest frame, $|\cos\theta^*|$ in the inclusive sample, and also under the requirement of no activity in the forward direction. The total integrated fiducial cross-section is measured to be $215 \pm 1 \text{(stat.)} ^{+23}_{-20} \text{(syst.)} \pm 4 \text{(lumi.)} \mu$b. Within experimental uncertainties the measured integrated cross-section is in good agreement with the QED predictions from the Monte Carlo programs Starlight and SuperChic, confirming the broad features of the initial photon fluxes. The differential cross-sections show systematic differences with these predictions which are more pronounced at high $|y_{ee}|$ and $|\cos\theta^*|$ values.

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. SLHA files for benchmark signal (direct squark pair production)

Biodiversity can dampen the effects of ecosystem variability through diversification of portfolio assets providing the environmental stability that supports economies and cultures. We examined how elements of salmon biodiversity affect interannual catch stability and within-year season length (opportunity) of First Nations fisheries in the Fraser River watershed from 1983 to 2012 across 5 different species of salmon. Stability and opportunity increased in fisheries with access to increasing richness, as fisheries were closer to the ocean, in mainstem fisheries relative to tributary fisheries, and in fisheries downstream of a partial barrier. The importance of different elements of salmon biodiversity on catch stability varied by species. Richness was the most ubiquitous explanatory variable of fishing opportunity across all species. Through a novel application of spatial portfolio theory, this research quantifies the portfolio effect in fisheries across the Fraser and links basic diversity-stability theory to First Nations food security.

This paper presents a search for hypothetical massive, charged, long-lived particles with the ATLAS detector at the LHC using an integrated luminosity of $139 \mathrm{fb^{-1}}$ of proton--proton collisions at $\sqrt{s}=13 \text{TeV}$. These particles are expected to move significantly slower than the speed of light and should be identifiable by their high transverse momenta and anomalously large specific ionisation losses, $dE/dx$. Trajectories reconstructed solely by the inner tracking system and a $dE/dx$ measurement in the pixel detector layers provide sensitivity to particles with lifetimes down to ${\cal O}(1) \text{ns}$ with a mass, measured using the Bethe--Bloch relation, ranging from $100 \text{GeV}$ to 3 $\text{TeV}$. Interpretations for pair-production of $R$-hadrons, charginos and staus in scenarios of supersymmetry compatible with these particles being long-lived are presented, with mass limits extending considerably beyond those from previous searches in broad ranges of lifetime. a pseudo-code implementing instruction in Guide.pdf