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DOE OSTI2014

Electroweak measurements from W, Z and photon final states

We present the most recent precision electroweak measurements of single $W$ and $Z$ boson cross section and properties from the LHC and Tevatron colliders, analyzing data collected by ATLAS, CDF, CMS, D0, and LHCb detectors. The results include the measurement of the single $W$ and $Z$ boson cross section at LHC, the differential cross section measurements, the measurement of $W$ boson mass, the measurement of $W$ and $Z$ charge asymmetry. These measurements provide precision tests on the electroweak theory, high order predictions and the information can be used to constraint parton distribution functions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

A general-mass scheme for prompt charm production at hadron colliders

In these proceedings, we apply the recently developed S-ACOT-MPS factorization scheme at the next-to-leading order to prompt charm production at hadron colliders. It provides a good agreement with experimental data on charm meson production measured by LHCb at 7 and 13 TeV. The low- p_T p T data are on the margins of the theoretical error bands, emphasizing the importance of including contributions beyond the next-to-leading order.

Xie, Keping↗

DOE OSTI2013

Compendium of Instrumentation Whitepapers on Frontier Physics Needs for Snowmass 2013

Contents of collection of whitepapers include: Operation of Collider Experiments at High Luminosity; Level 1 Track Triggers at HL-LHC; Tracking and Vertex Detectors for a Muon Collider; Triggers for hadron colliders at the energy frontier; ATLAS Upgrade Instrumentation; Instrumentation for the Energy Frontier; Particle Flow Calorimetry for CMS; Noble Liquid Calorimeters; Hadronic dual-readout calorimetry for high energy colliders; Another Detector for the International Linear Collider; e+e- Linear Colliders Detector Requirements and Limitations; Electromagnetic Calorimetry in Project X Experiments The Project X Physics Study; Intensity Frontier Instrumentation; Project X Physics Study Calorimetry Report; Project X Physics Study Tracking Report; The LHCb Upgrade; Neutrino Detectors Working Group Summary; Advanced Water Cherenkov R&D for WATCHMAN; Liquid Argon Time Projection Chamber (LArTPC); Liquid Scintillator Instrumentation for Physics Frontiers; A readout architecture for 100,000 pixel Microwave Kinetic In- ductance Detector array; Instrumentation for New Measurements of the Cosmic Microwave Background polarization; Future Atmospheric and Water Cherenkov ?-ray Detectors; Dark Energy; Can Columnar Recombination Provide Directional Sensitivity in WIMP Search?; Instrumentation Needs for Detection of Ultra-high Energy Neu- trinos; Low Background Materials for Direct Detection of Dark Matter; Physics Motivation for WIMP Dark Matter Directional Detection; Solid Xenon R&D at Fermilab; Ultra High Energy Neutrinos; Instrumentation Frontier: Direct Detection of WIMPs; nEXO detector R&D; Large Arrays of Air Cherenkov Detectors; and Applications of Laser Interferometry in Fundamental Physics Experiments.

Lipton, R.↗

DOE OSTI2019

Physics Models in Detector Simulation [PowerPoint]

This talk provides an overview of the detector simulation physics models needs of HEP experiments and is restricted to LHC experiments (ALICE, ATLAS, CMS, LHCb) and Belle II and will be focused on the Geant4 toolkit. Other experiments are discussed in other talks. This talk also discuss differences and commonalities among experiments and will identify opportunities for collaboration.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2020

Far-forward neutrinos at the Large Hadron Collider

We present a new calculation of the energy distribution of high-energy neutrinos from the decay of charm and bottom hadrons produced at the Large Hadron Collider (LHC). In the kinematical region of very forward rapidities, heavy-flavor production and decay is a source of tau neutrinos that leads to thousands of charged-current tau neutrino events in a 1 m long, 1 m radius lead neutrino detector at a distance of 480 m from the interaction region. In our computation, next-to-leading order QCD radiative corrections are accounted for in the production cross-sections. Non-perturbative intrinsic-k T effects are approximated by a simple phenomenological model introducing a Gaussian k T -smearing of the parton distribution functions, which might also mimic perturbative effects due to multiple initial-state soft-gluon emissions. The transition from partonic to hadronic states is described by phenomenological fragmentation functions. To study the effect of various input parameters, theoretical predictions for $D^{±}_s$ production are compared with LHCb data on double-differential cross-sections in transverse momentum and rapidity. The uncertainties related to the choice of the input parameter values, ultimately affecting the predictions of the tau neutrino event distributions, are discussed. We consider a 3+1 neutrino mixing scenario to illustrate the potential for a neutrino experiment to constrain the 3+1 parameter space using tau neutrinos and antineutrinos. We find large theoretical uncertainties in the predictions of the neutrino fluxes in the far-forward region. Untangling the effects of tau neutrino oscillations into sterile neutrinos and distinguishing a 3+1 scenario from the standard scenario with three active neutrino flavours, will be challenging due to the large theoretical uncertainties from QCD.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2015

Search for Hidden-Charm Pentaquark with CLAS12

Search for Hidden-Charm Pentaquark with CLAS12 is discussed. It was shown that CLAS12 detector has enough acceptance and sensitivity for the detailed studies of recently announced by LHCb charmonium-pentaquark states.

Kubarovsky, Valery↗

DOE OSTI2019

Experiment GlueX: Early results and future plans

The GlueX experiment in Hall D at Jefferson Lab has just finished the data taking for the first phase of the project. The main purpose of the experiment is the search for hybrid mesons in the light quark sector. The experiment studies interactions of a linearly polarized photon beam made by 11.7 GeV electrons with a hydrogen target, with the help of a nearly hermetic spectrometer for charged and neutral particles. About 25% of the data acquired have been analyzed. The first physics results include studies of photoproduction of light mesons by a linearly polarized beam, and a measurement of the J/psi photoproduction close to threshold. The latter allows to search for the LHCb's pentaquarks in photoproduction. The first results on the search for hybrid mesons are expected after the whole data sample has been analyzed. The next stage of GlueX data taking will include a new detector for charged kaon identification, and will run at higher luminosity, in order to search for hybrid mesons decaying to strange particles, as well as to contribute to the spectroscopy of hyperons. I will also discuss a proposal to modify the Hall D facility in order to provide a K0L beam, which would allow to study strange baryons and mesons at a new level of precision.

Chudakov, Eugene↗

DOE OSTI2017

Hadron Spectroscoy at JPAC

We review some of the recent achievements of the Joint Physics Analysis Center, a theoretical collaboration with ties to experimental collaborations, which aims at providing amplitudes suitable for the analysis of the experimental data on hadron physics. Since its foundation in 2013, the group is focused on hadron spectroscopy in preparation for the present and forthcoming high statistics experiments, as Belle II, BESIII, CLAS12, GlueX, COMPASS and LHCb.

Pilloni, Alessandro↗

DOE OSTI2017

Hadron Structure Studies with a Fixed-Target Experiment at the LHC - AFTER@LHC

I will illustrate some of the opportunities for hadron structure studies at a future multi-purpose fixed-target experiment at the LHC. The proton beams at the LHC allow for the most energetic fixed-target experiments ever performed, opening new kinematic windows on hadron and nuclear physics which integrate the knowledge available from collider experiments (in particular RHIC and EIC).?? I will discuss how AFTER@LHC will shed light on the proton-spin puzzle by investigating Transverse-Momentum Dependent parton distribution functions (TMDs). Unpolarized proton-proton collisions allow to access unpolarized quark and gluon TMDs, the Boer-Mulders quark TMD and the distribution of linearly polarized gluons in unpolarized protons. Looking at polarized targets, single-transverse-spin asymmetries (STSAs) for processes such as Drell-Yan lepton-pair and quarkonium production will allow measurements of polarized TMDs for quarks and gluons, such as the Sivers functions. Moreover, I will show how, thanks to the boost of the fixed target mode, the acceptance of detectors like LHCb and ALICE in the fixed-target mode allows to analyze processes which are sensitive to the intrinsic charm content of the proton. In particular, I will address some aspects of D meson, charm + photon as well as J/psi-pair production.

Signori, Andrea↗

DOE OSTI2023

CMS Physics Results in the LHC Runs 2,3

The Large hadron Collider at CERN and four scientific collaborations: Alice, ATLAS, CMS, LHCb are in operation since September 2008. The accelerator delivered and the experiments processed trillions of events of proton-proton and heavy ions collisions and provided useful data for thousands of physics analyses and publications. The jewel of the published data is a discovery in 2012 of the long anticipated Higgs boson. During the operation time the regular acquisition of data was interleaved with two periods of maintenance, Long-shutdown-1 (2013-2015) and Long-shutdown-2 (2018-2022), which resulted in several improvements to the machine and the experiments. The CMS collaboration recorded to date two large physics datasets of pp collision data. The first dataset, called Run 2, was recorded between 2015 and 2018 with 140fb-1 of integrated luminosity taken at 13TeV of center of mass energy. The second dataset, called Run 3, has just started in 2022 and it has been recording pp collision data at 13.6 TeV of center of mass energy, with 80 fb-1 of data collected till the end of July 2023.For my presentation I selected the most recent results produced by CMS from Run2 and Run 3 which are covering the topics of Higgs boson properties, searches for new particles and additional scalars, top quark production and properties, and I am discussing other interesting models e.g. using SM particles as portals to the Dark matter.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2023

J/psi photoproduction close to threshold at GlueX

Close-to-threshold photoproduction probes small-size gluon configurations in the proton. Under certain assumptions it allows us to study the proton properties, as gluonic GPDs, anomalous contribution to the mass of the proton, gravitational form factors, and the mass radius of the proton. A careful comparison of the experimental data with the theoretical predictions would help us to verify the validity of those assumptions. The first cross-section measurements of near-threshold reaction by the GlueX Collaboration (Phys. Rev. Lett. 123, 072001 (2019)) has attracted a considerable theoretical interest. Along with the relation to the gluonic properties of the proton, the measurement exploited a possibility of the LHCb Pentaquark production in the s-channel of the observed reaction, placing a limit of the decay probability . Here we present new GlueX results based on a four-times larger data set. The higher statistics along with the full acceptance of the GlueX spectrometer allow us to measure the differential cross section in several energy ranges and compare the results with several theoretical calculations.

Chudakov, Eugene↗

DOE OSTI2016

Review of top quark production at LHC and Tevatron

A summary of recent results on top quark production at LHC and Tevatron are presented in this paper. The measurements of top quark production were performed in various energies ($\sqrt s$ = 1.96, 7, 8, 13 TeV) and initial states ($p \bar{p}$ and $p p$) by the ATLAS, CDF, CMS, DØ and LHCb ex- periments. The measured top quark pair production cross-section is in good agreement with the standard model predictions in each energy region. Differential cross-sections were also measured and compared with several theoretical predictions. Most of the higher order QCD models reproduce the experimental data well, while a slight discrepancy in a certain phase space such as higher top quark $p_{T}$ region is observed. Electroweak single top quark production was also measured and the results are consistent with theoretical predictions at the various energies.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2018

Measurement of the $J/\psi$ photoproduction cross section close to threshold

We will present preliminary results for the J/psi close-to threshold photoproduction obtained in the GlueX experiment at Jefferson Lab. Close-to-threshold photoproduction gamma+p-->J/psi+p probes small-size gluon configuration in the proton. This reaction may also contain a contribution from the s-channel production of the LHCb pentaquark P(4.4)-->J/psi+p at beam energies of about 10 GeV. Measuring the size of the contribution allows to evaluate, or put a limit on the branching ratio of the decay P-->J/psi+p. The GlueX experiment is in the process of collecting data. The main research topic is the spectroscopy of light mesons produced by a linearly polarized photon beam with the end point of 12 GeV.

Chudakov, Eugene↗

DOE OSTI2019

Beyond the Standard Model physics at the HL-LHC and HE-LHC

This is the third out of five chapters of the final report of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as $3$ ab$^{-1}$ of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as $15$ ab$^{-1}$ of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by $20-50\%$ on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2025

Training and onboarding initiatives in high energy physics experiments

In this article we document the current analysis software training and onboarding activities in several High Energy Physics (HEP) experiments: ATLAS, CMS, LHCb, Belle II and DUNE. Fast and efficient onboarding of new collaboration members is increasingly important for HEP experiments. With rapidly increasing data volumes and larger collaborations the analyses and consequently, the related software, become ever more complex. This necessitates structured onboarding and training. Recognizing this, a meeting series was held by the HEP Software Foundation (HSF) in 2022 for experiments to showcase their initiatives. Here we document and analyze these in an attempt to determine a set of key considerations for future HEP experiments.

analysis software↗

DOE OSTI2026

Eta Fragmentation Functions Revisited

We revisit the extraction of parton-to-eta meson fragmentation functions at next-to-leading order accuracy in QCD in the light of the recent hadroproduction measurements in proton-proton collisions obtained by the PHENIX, LHCb, and ALICE collaborations. In addition to an increased precision, the data explore complementary rapidity ranges and center-of-mass system energies. The analysis exploits the theoretical scale dependence to ease tensions among the data sets at different energies that are potentially caused by QCD corrections beyond the next-to-leading order. The resulting set of fragmentation functions yields a consistent description of all available data. Estimates of uncertainties are obtained with the Monte Carlo replica method.

FOS: Physical sciences↗

DOE OSTI2019

Threshold J / ψ Photoproduction with GlueX at Jefferson Lab

We report preliminary results for the $\gamma p \rightarrow J/\psi p$ exclusive cross-section from the threshold up to a photon energy of $12$ GeV. These measurements have a direct relation to the pentaquarks, $P^+_c(4380)$ and $P^+_c(4450)$, reported by LHCb, expected to be seen in the $s$-channel photoproduction $\gamma p \rightarrow P_c \rightarrow J/\psi p$, allowing to put a limit on the $P^+_c(4450) \rightarrow J/\psi p$ branching ratio. The near threshold production mechanism is discussed, as well. The GlueX experiment uses a tagged-photon beam produced by electrons from the 12 GeV CEBAF machine. The detector system is based on a 2 T solenoid and includes electro-magnetic calorimeters and drift chambers providing full acceptance coverage. The $J/\psi $ particles are registered by their decay into $e^+e^-$ pairs identified in the calorimeters. Taking advantage of the exclusivity of the reaction and the precise knowledge of the beam energy, we achieve a high mass resolution and a very low background, allowing us to perform a more sensitive unbinned analysis.

Pentchev, Lubomir↗

DOE OSTI2011

$W/Z$ and Diboson Properties

Most recent measurements of properties of W and Z gauge bosons at hadron colliders are presented. The measurements were performed by ATLAS, CMS, and LHCb collaborations with proton-proton collisions at the LHC and by CDF and D0 collaborations with proton-antiproton collisions at the Tevatron. Center-of-mass energy was 7 TeV and 1.96 TeV at the LHC and Tevatron respectively. Integrated luminosity ranges from 35 pb{sup -1} to 1.02 pb{sup -1} for LHC and from 0.2 fb{sup -1} to 7.1 fb{sup -1} for Tevatron.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗