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Creators/Authors contains: "Jas, Mainak"

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  1. The aim of this study was to estimate standard crop coefficients of surface and sub-surface drip-irrigated young almond trees under non-limiting soil water content conditions, based on measurements of the fraction of ground covered by the canopy (fc) and tree height (h) (A&P approach proposed by Allen and Pereira (2009)) and to improve the transferability of them to the productive sector once weather data (i.e. maximum and minimum air temperature (Tmax and Tmin, respectively), as well as dew point temperature (Tdew)) were adjusted to the reference conditions. A 4 year field experiment was carried out in a ~ 12.5 ha commercial young almond (Prunus dulcis (Mill.) D.A. Webb) orchard located in Hellín, (SE Spain). 'Penta' almond trees, grafted onto the GF-677 rootstock, were planted in 2018. Field measurements of fc and h were performed over four consecutive growing seasons from 2019 to 2022. In parallel, ETo computed by the nearest meteorological station, located at a non-reference weather site, was reduced around 6% after bringing weather data closer to the reference conditions, while actual crop evapotranspiration and its components (actual tree transpiration and soil evaporation) were estimated in each irrigation system through the so-called simplified two-source energy balance (STSEB) model in order to be used as a quality assessment of the A&P approach. The ratio between the former estimations and the ETo allowed to compute STSEB-based crop coefficients. No significant differences in effective canopy cover (fc eff) nor h were observed between the two irrigation systems, and thus the estimated Kcb values were the same for both drip-irrigation systems. fc eff values during mid-season stage ranged between 0.15 in 2019 and 0.62 in 2022, whereas average h values for this stage ranged between 2.36 and 3.80 m in 2019 and 2022, respectively. These values of fc eff and h resulted in average mid-season basal crop coefficients (Kcb-mid) of 0.28 in 2019, 0.39 in 2020, 0.61 in 2021 and 1.02 in 2022. Soil evaporation estimates through STSEB model were significantly different between the two irrigation systems, leading to differences in Ke being around 16% higher for DI than SDI. Moreover, the intra-annual Kc values moved in the same range for the initial, mid- and end-season crop growth stages, varying from 0.30 in 2019 to 1.01 in 2022, computed under standard conditions. Finally, the A&P approach was shown to be an especially interesting method for estimating Kcb values in almond fruit trees, being useful for refining Kcb and/or Kc for conditions of plant spacing, size and density that may differ from standard values. In this way, irrigation scheduling can be optimized regarding the almond tree architecture (i.e. fc eff and h), allowing to manage properly irrigation water to meet the tree water demands. 
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  2. Free, publicly-accessible full text available September 1, 2026
  3. This paper presents a search for massive, charged, long-lived particles with the ATLAS detector at the Large Hadron Collider using an integrated luminosity of $$140~fb^{−1}$$ of proton-proton collisions at $$\sqrt{s}=13$$~TeV. These particles are expected to move significantly slower than the speed of light. In this paper, two signal regions provide complementary sensitivity. In one region, events are selected with at least one charged-particle track with high transverse momentum, large specific ionisation measured in the pixel detector, and time of flight to the hadronic calorimeter inconsistent with the speed of light. In the other region, events are selected with at least two tracks of opposite charge which both have a high transverse momentum and an anomalously large specific ionisation. The search is sensitive to particles with lifetimes greater than about 3 ns with masses ranging from 200 GeV to 3 TeV. The results are interpreted to set constraints on the supersymmetric pair production of long-lived R-hadrons, charginos and staus, with mass limits extending beyond those from previous searches in broad ranges of lifetime 
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    Free, publicly-accessible full text available July 1, 2026
  4. ABSTRACT We cross-correlate positions of galaxies measured in data from the first three years of the Dark Energy Survey with Compton-y maps generated using data from the South Pole Telescope (SPT) and the Planck mission. We model this cross-correlation measurement together with the galaxy autocorrelation to constrain the distribution of gas in the Universe. We measure the hydrostatic mass bias or, equivalently, the mean halo bias-weighted electron pressure 〈bhPe 〉, using large-scale information. We find 〈bhPe 〉 to be $$[0.16^{+0.03}_{-0.04},0.28^{+0.04}_{-0.05},0.45^{+0.06}_{-0.10},0.54^{+0.08}_{-0.07},0.61^{+0.08}_{-0.06},0.63^{+0.07}_{-0.08}]$$ meV cm−3 at redshifts z ∼ [0.30, 0.46, 0.62, 0.77, 0.89, 0.97]. These values are consistent with previous work where measurements exist in the redshift range. We also constrain the mean gas profile using small-scale information, enabled by the high-resolution of the SPT data. We compare our measurements to different parametrized profiles based on the cosmo-OWLS hydrodynamical simulations. We find that our data are consistent with the simulation that assumes an AGN heating temperature of 108.5 K but are incompatible with the model that assumes an AGN heating temperature of 108.0 K. These comparisons indicate that the data prefer a higher value of electron pressure than the simulations within r500c of the galaxies’ haloes. 
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  5. This report presents a comprehensive collection of searches for new physics performed by the ATLAS Collaboration during the Run~2 period of data taking at the Large Hadron Collider, from 2015 to 2018, corresponding to about 140~$$^{-1}$$ of $$\sqrt{s}=13$$~TeV proton--proton collision data. These searches cover a variety of beyond-the-standard model topics such as dark matter candidates, new vector bosons, hidden-sector particles, leptoquarks, or vector-like quarks, among others. Searches for supersymmetric particles or extended Higgs sectors are explicitly excluded as these are the subject of separate reports by the Collaboration. For each topic, the most relevant searches are described, focusing on their importance and sensitivity and, when appropriate, highlighting the experimental techniques employed. In addition to the description of each analysis, complementary searches are compared, and the overall sensitivity of the ATLAS experiment to each type of new physics is discussed. Summary plots and statistical combinations of multiple searches are included whenever possible. 
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    Free, publicly-accessible full text available April 22, 2026
  6. Top-quark pair production is observed in lead–lead ( Pb + Pb ) collisions at s NN = 5.02 TeV at the Large Hadron Collider with the ATLAS detector. The data sample was recorded in 2015 and 2018, amounting to an integrated luminosity of 1.9 nb 1 . Events with exactly one electron and one muon and at least two jets are selected. Top-quark pair production is measured with an observed (expected) significance of 5.0 (4.1) standard deviations. The measured top-quark pair production cross section is σ t t ¯ = 3.6 0.9 + 1.0 ( stat ) 0.5 + 0.8 ( syst ) μ b , with a total relative uncertainty of 31%, and is consistent with theoretical predictions using a range of different nuclear parton distribution functions. The observation of this process consolidates the evidence of the existence of all quark flavors in the preequilibrium stage of the quark-gluon plasma at very high energy densities, similar to the conditions present in the early Universe. © 2025 CERN, for the ATLAS Collaboration2025CERN 
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    Free, publicly-accessible full text available April 1, 2026
  7. A<sc>bstract</sc> A study of the Higgs boson decaying into bottom quarks (H→$$ b\overline{b} $$ b b ¯ ) and charm quarks (H→$$ c\overline{c} $$ c c ¯ ) is performed, in the associated production channel of the Higgs boson with aWorZboson, using 140 fb−1of proton-proton collision data at$$ \sqrt{s} $$ s = 13 TeV collected by the ATLAS detector. The individual production ofWHandZHwithH→$$ b\overline{b} $$ b b ¯ is established with observed (expected) significances of 5.3 (5.5) and 4.9 (5.6) standard deviations, respectively. Differential cross-section measurements of the gauge boson transverse momentum within the simplified template cross-section framework are performed in a total of 13 kinematical fiducial regions. The search for theH→$$ c\overline{c} $$ c c ¯ decay yields an observed (expected) upper limit at 95% confidence level of 11.5 (10.6) times the Standard Model prediction. The results are also used to set constraints on the charm coupling modifier, resulting in|κc| <4.2 at 95% confidence level. Combining theH→$$ b\overline{b} $$ b b ¯ andH→$$ c\overline{c} $$ c c ¯ measurements constrains the absolute value of the ratio of Higgs-charm and Higgs-bottom coupling modifiers (|κcb|) to be less than 3.6 at 95% confidence level. 
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    Free, publicly-accessible full text available April 1, 2026
  8. The ATLAS experiment has developed extensive software and distributed computing systems for Run 3 of the LHC. These systems are described in detail, including software infrastructure and workflows, distributed data and workload management, database infrastructure, and validation. The use of these systems to prepare the data for physics analysis and assess its quality are described, along with the software tools used for data analysis itself. An outlook for the development of these projects towards Run 4 is also provided. 
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    Free, publicly-accessible full text available March 6, 2026
  9. A<sc>bstract</sc> Differential measurements of Higgs boson production in theτ-lepton-pair decay channel are presented in the gluon fusion, vector-boson fusion (VBF),VHand$$ t\overline{t}H $$ t t ¯ H associated production modes, with particular focus on the VBF production mode. The data used to perform the measurements correspond to 140 fb−1of proton-proton collisions collected by the ATLAS experiment at the LHC. Two methods are used to perform the measurements: theSimplified Template Cross-Section(STXS) approach and anUnfolded Fiducial Differentialmeasurement considering only the VBF phase space. For the STXS measurement, events are categorized by their production mode and kinematic properties such as the Higgs boson’s transverse momentum ($$ {p}_{\textrm{T}}^{\textrm{H}} $$ p T H ), the number of jets produced in association with the Higgs boson, or the invariant mass of the two leading jets (mjj). For the VBF production mode, the ratio of the measured cross-section to the Standard Model prediction formjj> 1.5 TeV and$$ {p}_{\textrm{T}}^{\textrm{H}} $$ p T H > 200 GeV ($$ {p}_{\textrm{T}}^{\textrm{H}} $$ p T H < 200 GeV) is$$ {1.29}_{-0.34}^{+0.39} $$ 1.29 0.34 + 0.39 ($$ {0.12}_{-0.33}^{+0.34} $$ 0.12 0.33 + 0.34 ). This is the first VBF measurement for the higher-$$ {p}_{\textrm{T}}^{\textrm{H}} $$ p T H criteria, and the most precise for the lower-$$ {p}_{\textrm{T}}^{\textrm{H}} $$ p T H criteria. Thefiducialcross-section measurements, which only consider the kinematic properties of the event, are performed as functions of variables characterizing the VBF topology, such as the signed ∆ϕjjbetween the two leading jets. The measurements have a precision of 30%–50% and agree well with the Standard Model predictions. These results are interpreted in the SMEFT framework, and place the strongest constraints to date on the CP-odd Wilson coefficient$$ {c}_{H\overset{\sim }{W}} $$ c H W ~
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    Free, publicly-accessible full text available March 1, 2026