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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Final Report: Magnetotransport studies of low dimensional electron systems based on GaAs/AlGaAs heterostructures and graphene

Emergence is the process of complex behaviors arising out of a multiplicity of basic interactions. Emergent phenomena often exhibit remarkable, useful, and collective aspects - features which have helped to make emergent behavior a topic of current research. A high quality GaAs/AlGaAs two-dimensional electron system subjected to modest microwave/terahertz photo-excitation at low temperature exhibits radiation-induced zero-resistance states at small magnetic fields, and this phenomenon has been cited as evidence for emergence in a driven, steady state non-equilibrium context. Since the initial observations, photo-excited electronic systems have become a popular arena to search for new physical phenomena.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Measuring the Precession Frequency in the E989 Muon g – 2 Experiment

The E989 Muon $g-2$ Experiment aims to measure the anomalous magnetic moment of the muon, $a_\mu$, to an unprecedented precision of 140 parts per billion (ppb). There currently stands a greater than 3$\sigma$ discrepancy between the best measurement of $a_\mu$ and its theoretical value predicted using the Standard Model. The E989 experiment seeks to either resolve or confirm this discrepancy, which is suggestive of new physics interactions within reach of many contemporary experiments. To achieve the E989 target precision, the anomalous precession frequency, $\omega_a$, of muons in a magnetic storage ring must be determined with a systematic uncertainty below 70\,ppb. This frequency is imprinted on the time-dependent energy distribution of decay positrons observed by 24 electromagnetic calorimeters. These calorimeters feature a novel design optimized expressly for the stringent demands of the $\omega_a$ measurement. This dissertation outlines the motivation for and measuremen t principles behind E989, discusses the requirements, prototyping, testing, commissioning, and operations of the electromagnetic calorimeters, and presents a preliminary, blinded analysis of data collected in the spring of 2018.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Laying the Foundation for a Predictive Theory of Electroweak Nuclear Phenomena

Reliable model-independent predictions of nuclear processes such as beta-decay and neutrinonucleus scattering are important for many fundamental science and mission-related investigations; For example, accurate descriptions of as beta-decay are required for modeling the anti-neutrino spectrum of nuclear reactor, whether for trying to detect new physics such as sterile neutrinos, or remotely identifying the purpose of that reactor. For these activities, we need accurate calculations, as well as careful and thorough analyses of theoretical error and uncertainty in the underlying models and the many-body methods and codes used in solving that model. Unfortunately, modern theoretical calculations of these processes are inadequate for this task. At the heart of this inadequacy is the interaction between nucleons and other particles known as nuclear currents. Historically, descriptions of nuclear currents took into account only the simplest of particle interactions. Recently, the development of an effective field theory known as chiral EFT has been used to derive large corrections to these particle interactions. However, the complex nature of these corrections inhibited their use in ab initio methods of predicting nuclear processes. We developed a novel method to address these complexities and applied it in a series of benchmark and demonstrative calculations using state-of-the-art quantum few-nucleon solvers. Specifically, we studied the role of two-nucleon currents in electroweak processes using light nuclei (i.e., nuclei containing fewer than five nucleons) as a workbench to compute these processes and quantify their uncertainties using Bayesian extensions of the EFT.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2019

Precision measurement of the weak charge of the proton and parity violation in the N → Δ transition

The Q weak Experiment ran for two and a half years at the Thomas Jefferson National Accelerator Facility in pursuit of Q$^p_w$, the neutral weak analog to the electric charge of the proton. Q weak measured the parity-violating asymmetry in elastic electron-proton scattering at an extreme forward angle (Q 2 = 0.0249 (GeV/c) 2 ). From the data gathered via the 1.16 GeV 180 µA longitudinally polarized electron beam scattering off the unpolarized photons in the liquid hydrogen target, a value of Q$^p_w$ (PVES) = 0.0719 ± 0.0045 was determined. The Standard Model has a definite prediction of Q$^p_w$ (SM) = 0.0708 ± 0.0003, consistent with the value determined by Q weak which sets a limit on possible new physics up to 7.5 TeV. The theory behind the main measurement of the Q weak Experiment is described in this document, along with the apparatus that made the measurement possible. Understanding the kinematics of the apparatus was a vital component to Q weak 's final measurement. An in-depth explanation of the tracking system responsible for benchmarking the momentum transfer and scattering angle simulations is included. The unblinded analysis of Q weak 's final result is outlined, as are additional physics results related to the N → Δ transition. During April 2012, an opportunity was seized to take ancillary data on the inelastic N → Δ transition at a different beam energy(877 MeV) than the nominal Q weak data. This data, combined with the inelastic data taken at nominal beam energy and a previous measurement, determined a constraint on d Δ , a low energy constant related to hadronic parity violation, of (3.8 ± 14.7) g π . It also resulted in a measurement of the beam-normal single-spin asymmetry of the N → Δ transition of 149 ± 3 (stat) ± 72 (syst) ppm. This document includes both the longitudinal and transverse analysis of the 877 MeV data.

Lee, Anna↗
DOE OSTI2019

The Mu2e Experiment [PowerPoint - 2019]

The Mu2e experiment is primarily a search for Charged Lepton Flavor Violation (CLFV) at Fermilab to show clear evidence of New Physics. Various aspects of the experiment are described.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2018

Searching for Muon to Electron Conversion: The Mu2e Experiment at Fermilab [PowerPoint]

Mu2e at Fermilab will search for neutrinoless conversion of a muon to an electron in a nuclear environment: μ -N → e -N . This would violate charged lepton flavor, something that has never been seen before. Any detection of charged lepton flavor violation would be an unambiguous sign of new physics. The Mu2e goal is a 10 4 improvement. The specifics and schedule for Mu2e are provided.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Development, Demonstration and Validation of Data-Driven Compact Diode Models for Circuit Simulation and Analysis

Compact semiconductor device models are essential for efficiently designing and analyzing large circuits. However, traditional compact model development requires a large amount of manual effort and can span many years. Moreover, inclusion of new physics (e.g., radiation effects) into an existing model is not trivial and may require redevelopment from scratch. Machine Learning (ML) techniques have the potential to automate and significantly speed up the development of compact models. In addition, ML provides a range of modeling options that can be used to develop hierarchies of compact models tailored to specific circuit design stages. In this paper, we explore three such options: (1) table-based interpolation, (2) Generalized Moving Least-Squares, and (3) feedforward Deep Neural Networks, to develop compact models for a p-n junction diode. We evaluate the performance of these "data-driven" compact models by (1) comparing their voltage-current characteristics against laboratory data, and (2) building a bridge rectifier circuit using these devices, predicting the circuit's behavior using SPICE-like circuit simulations, and then comparing these predictions against laboratory measurements of the same circuit.

1N4148 switching diode↗
DOE OSTI2020

Study of the Mu2e sensitivity to the $\mu^-\rightarrow e^+$ conversion process

The Mu2e experiment at Fermilab (Batavia, IL) will search for the coherent neutrinoless conversion of a muon into an electron in the electric field of an aluminum atom. The conversion process results in a monochromatic electron with energy slightly below the muon rest mass ($E_e= 104.97$ MeV). The experiment goal is to improve the previous measurement by four orders of magnitude and reach a single event sensitivity of $3 \times 10^{-17} $ on the conversion rate with respect to the muon capture rate. \\ The experiment will deliver a very intense pulsed negative muon beam to an aluminum target to achieve a total number of $10^{18}$ stopped muons in three years of running. Production and transport of the muons are accomplished with a sophisticated magnetic system comprised of a Production, a Transport and a Detector solenoid, with the last one hosting a Straw-tube Tracker and a Crystal Calorimeter. The entire detector region is surrounded by a Cosmic Ray Veto system. Mu2e is und er construction at the Muon Campus of Fermilab. \\ The INFN italian group is responsible for the design and construction of the crystal calorimeter, which plays a crucial role in the Mu2e measurement, providing particle identification capabilities fundamental for the rejection of the different background sources that can mimic a conversion electron. The calorimeter information allows also to improve the tracking performances it provides a fast standalone trigger for the experiment.\\ After a long R\&D phase, the final drawings see a calorimeter comprised of 1348 pure CsI crystals arranged in two annular disks. Each crystal is readout by two custom UV-extended Silicon Photomultipliers (SiPMs). Performances of the selected components were verified with an electron beam test, carried out in 2017 at the Beam Test Facility (BTF) at the National Laboratories of Frascati, on a large size prototype of 51 crystals and 102 SiPMs, confirming excellent energy ($\sigma_{E}/E = \mathcal{O }(10\%)$) and timing ($\sigma_{T} <500$ ps) resolutions in a! greement with the Mu2e specifications.\\ In the first chapters of this thesis, I describe my involvement in the calorimeter activities, with particular emphasis on the data analysis of the prototype energy response and resolution, that I was personally leading. Moreover, a description of the tuning of the simulation and the careful data-MC comparison is also reported.\\ An auxiliary measurement that can be performed with Mu2e is the search for a Lepton Number Violation (LNV) process where the negatively charged muon converts, without neutrinos, into a positron, $\mu ^{-} +N(A,Z) \rightarrow $ e$^+ +N(A,Z-2)$. At the moment of writing, Neutrinoless Double Beta Decay (0$\nu \beta \beta$) has set the most stringent limit on the LNV processes (T$^{0\nu \beta \beta}_{1/2} > 1.1 \times 10^{26} $ yr at 90$\%$ CL) with the GERDA experiment. In 0$\nu \beta \beta$ a pair of free electrons is created in the transformation from a nucleus $(A, Z)$ into its daughter $(A, Z + 2)$, namely: $(A,Z)\rightarrow (A, Z+2) =2 e^-$. Similar transitions could proceed through the emission of a pair of positrons, double electron capture (EC), or EC and single emission of a positron, with the nucleus changing from $(A, Z)$ to $(A, Z - 2)$. All these variations are equally interesting when discussing of new Physics, since they all manifest a non-conservation of the number of leptons.\\ Moreover, recent studies show that, because of flavor effect, off-diagonal processes, such as the $\mu^- -e^+$ conversion, can have their rate enhanced with respect to processes occurring in the $e-e$ sector.\\ Mu2e will search for $\mu^- + Al(27,13) \rightarrow e^+ +Na(27,11)$, only considering ground state transition, producing a conversion positron with energy $E_{e^+}= 92.32 $ MeV.\\ This thesis is focused on this search. In particular, I developed an algorithm to account for the radiative corrections to be applied to the conversion positrons that resulted in a few percent reduction in s ignal acceptance.\\ One of the most prominent background to ! this sear! ch is the Radiative Muon Capture (RMC) $ \mu+ N(Z,A)\rightarrow \gamma + \nu_{\mu} + N(Z-1,A)$. The produced photon can convert, virtually or in the detector materials (in the following referred as internal or external conversion respectively) in an electron-positron pair, producing positrons with energies approaching the expected conversion energy. Experimental results from previous experiments indicate the RMC endpoint ($\kmax$) to be of $\sim$ 90 MeV. A precise modeling of this background is relevant due to the proximity of the photon spectrum endpoint to the positron conversion energy. The calorimeter group is obviously interested to reconstruct the RMC distribution having also the opportunity to improve the current knowledge of the process. \\ A toy MC has been developed to evaluate the number of $e^+$ from external RMC background in the signal window. Knowing this value and ev...

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Search for Anomalous Trilinear Couplings of Electroweak Gauge Bosons Using Angular Variables at $\sqrt{s}$ = 13 TeV at CMS

A study of techniques for improving limits placed on anomalous trilinear couplings of electroweak gauge bosons is presented. Electroweak gauge bosons couple to one another as well as to fermions. Deviations of these couplings from their standard model values would be a sign of new physics. Parameters that affect the couplings of the gauge bosons to each other also affect their helicity, which in turn may be measured from their decay products. Angles between the decay planes of the gauge bosons, as well as between their decay products, are measured. The analysis uses $35.9\,\text{fb}^{-1}$ of proton-proton collision data from the LHC taken with the CMS detector. Building on a prior analysis that measured the fiducial cross section of $pp \to WW/WZ \to \ell\nu jj$, we show that angular variables can improve limits on anomalous couplings even further.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Modeling of Charge Amplification in LArTPCs

Single-phase liquid argon time projection chambers (LArTPCs) are an important part of Fermilab's neutrino experimental program. Current LArTPCs are able to detect interactions producing energy deposits above the MeV scale, and focus on neutrinos at GeV energies. The Liquid Argon Charge Amplification Device, or LArCADe, program aims to employ modified anode geometries in order to obtain electron avalanches that would help reduce detection thresholds, opening the door to new physics opportunities at the keV scale (e.g. CEvNS and dark-matter WIMP searches). To model and quantify this phenomenon, a simulation of electron transport in LAr was built, able to simulate excitations and ionizations in non-uniform fields. Using COMSOL simulations of the anode structures, the built simulation produced quantitative and realistic estimates of LAr charge amplification near different tip geometries. These results will inform the next generation of tips produced for LArCADe.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

In situ monitoring of the stopped muon flux at Mu2e

The specific object of Mu2e search is the neutrino-less coherent $\mu^-\rightarrow e^-$ conversion in the field of an aluminum nucleus and the signal is a monoenergetic electron of energy $ \approx 104.97$ MeV. This process is forbidden in the Standard Model but allowed in many of its extensions: with minimal changes to include neutrino masses and oscillation, the Branching Ratio of this process, or the similarly interesting $\mu\rightarrow e \gamma$ decay, is expected to be of the order of $\mathcal{O}(10^{-54})$. Values like these are below any currently achievable experimental sensitivity, and the observation of a signal would be unambiguous evidence of New Physics. The upper limit on the muon conversion was set by SINDRUM II at $7\times10^{-13}$ (90\% C.L.) and the goal of the Mu2e collaboration is an improvement of 4 order of magnitudes.\\ The Mu2e experiment can be conceptually divided into three stages: interaction of the primary proton pulse with the tungsten target a nd production of $\pi$ and $\mu$; collection and transport of the produced particles down to the aluminum stopping target; interaction with the stopping target and measurement of the output particles. The measurement of the stopped muon flux is of cardinal importance for the normalization of the Mu2e results. The baseline design includes two detectors developed to measure this flux, counting $\gamma$ emitted by the muonic atoms: HPGe and LaBr$_3$(Ce). The studies performed by the Mu2e Collaboration show that these two systems can be reliably used to determine the overall normalization.\\ The number of stopped muons is proportional to the number of protons on target, which itself depends on the extraction system for the proton beam. The Mu2e beam delivery system will use a resonant extraction to create the proton pulses and this method is characterized by intensity fluctuations on the time scale of milliseconds. These fluctuations, aside from the proportional fluctuation of t he number of muons, have a non-trivial impact on the overall! performance of the apparatus. For example, higher intensity proton bunches translate into higher veto rates by the Cosmic Rays Veto system, which is triggered by secondary particles generated by the proton interaction. Another example is the effect of the instantaneous luminosity on the reconstruction efficiency: higher intensity translates into higher detector occupancy, which in turn reduces the reconstruction efficiency.\\ The two cited detectors encounter limitations when trying to monitor the flux at the millisecond timescales: HPGe is by construction a slow detector while the rate of emission of the $\gamma (1809\textrm{ keV})$ the LaBr$_3$(Ce) will measure is too low. As of today, no system allows to monitor these fluctuations and the goal of this Thesis is to try filling this gap. The method we developed to monitor the fluctuations of the stopped muon flux, and by extension, the fluctuation in the proton pulses intensity is based on counting the number of muons capt ured in the stopping target by counting the number of protons produced in the process of the nuclear muon capture. This is one of the possible processes a stopped muon can undergo and it can lead to the ejection of charged particles.\\ The reconstruction algorithms were developed by the Mu2e collaboration with the explicit (and sometimes implicit) aim to reconstruct tracks of electrons in an energy range of a conversion electron. The protons we are interested in behave quite differently from these electrons and the cardinal task of this study has been to tailor the reconstruction routines to these particles. This has been done by analyzing simulated events consisting of a single proton to optimize the procedure and understand the features of these tracks. A major difference with respect to the electrons is the non-relativistic nature of $100\div300$ MeV$/c$ protons: accounting for the low velocity is both a challenge and a unique signature of the tracks.\\ The use of a pulse d beam and the need to allow produced $\pi$ to decay and $\m! u$ to int! eract in the stopping target forces the definition of a Mu2e \textit{event}: an event is comprised by everything which happens in a $1.7\ \mu$s window between the incidence two consecutive proton pulses. This means that the reconstruction will be performed in an environment crowded by many different particles. The next step of this study has been to estimate the performance of the method in a fully-fledged Mu2e simulated event and to study what kind of selections would improve it.\\ Our results are satisfactory since the number of reconstructed protons is significant (few per event), and show that a monitor on the timescale of milliseconds is indeed possible.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2021

Negative Muon Count for the FNAL Muon g-2 Experiment

The primary goal of the FNAL Muon g-2 Experiment, located in Batavia, IL, USA, is to measure the anomalous magnetic dipole moment, a μ = (g-2)/2, of a muon to a precision of 0.14 ppm. Initial results from the experiment confirm a discrepancy between the experimental value of the muon anomaly compared with the theoretical value first discovered by the Brookhaven Muon g-2 Experiment in 2001. This discrepancy hints at new physics. However, running the experiment with negative muons is essential in order to verify the experimental value of the muon anomaly. As neither experiments nor simulation studies pertaining to the muon anomaly have been performed with negative muons, the goal of this work is to estimate the rates of negative muons arriving at the FNAL Muon g-2 experiment so that scientists can estimate the time required to run the experiment with negative muons. In order to do this, we performed several simulations of the Muon Campus, which delivers muons to the FNAL Muon g-2 Experiment, using the G4Beamline v. 3.06 at the National Energy Research Computing Center. We performed separate simulations for different sections of the muon campus, and simulations were repeated twice, once for negative muons and once for positive muons. An initial 10 9 protons were shot on target for both the negative and positive muon simulations. We found that the rate of negative muons arriving at the experiment was 0.549 times the rate of positive muons arriving at the experiment.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2022

Controlled Injection of Electrons for Improved Performance of Laser-Wakefield Acceleration

Our lab performed a series of experiments on controlled injection of LWFA with two extreme laser pulses: one laser pulse was used to drive LWFA. In contrast, the other precisely controls the injection of electrons into the wakefield plasma wave. We have demonstrated an efficient reduction of electron beam emittance by optical injection and novel spatio-temporal manipulation of the electron beam by the extreme laser-plasma waves. Moreover, the optical injection process involves unprecedented new physics, which will benefit studies in astrophysics, inertial confinement fusion, laser-driven x-ray light sources, and ultrafast science. We further improved the performance of LWFA by a better understanding and control of the extreme laser-plasma wave dynamics for optical injection. Three novel mechanisms were identified in the optical injection process: (1) collision of two laser pulses, (2) collision of a laser pulse with a wakefield plasma wave, and (3) collision of two laser wakefields. All three methods improved electron-beam energy spread, emittance, stability, and reproducibility. First, we identified, compared, and independently controlled these different injection mechanisms by controlling the polarization of the injector laser pulse. Second, we manipulated the spatiotemporal splitting of LWFA electron beams to reduce their emittance. Third, we applied the same laser-plasma-wave dynamics and the same experimental setup for improved performance of ion acceleration, which has also been predicted by the recent simulations.

43 PARTICLE ACCELERATORS↗
DOE OSTI2022

Evaluation of Gamma Ray Production - Quarterly Report FY22Q2

The LLNL team has performed the first systematic study of the effect of two-body weak currents in β decay rates across the entire mass table. In light and medium-mass nuclei, two-body weak currents from chiral effective field theory account for a significant portion of the phenomenological quenching of Gamow-Teller transition matrix elements. We examined the systematic effects of two-body axial currents on Gamow-Teller strength and β-decay rates in heavy nuclei within energy-density functional theory. We extended the charge-changing finiteamplitude pnFAM code to incorporate the contributions of two-body currents to the usual onebody linear response in the Gamow-Teller channel. We found that the two-body currents, as expected, usually quench both summed Gamow-Teller strength and decay rates, but by an amount that decreases as the neutron excess grows; see Fig. 1. In addition, they can enhance individual low-lying transitions, leading to decay rates that are quite different from those that an energy-independent quenching would produce, particularly in neutron-rich nuclei. This new physics capability is unique and provides the highest-fidelity description of β decay on the market. The underlying computational implementation can be reused to calculate γ-strength functions for finite-range nuclear potentials such as the Gogny force, which will allow us to benchmark some of our future developments against published results. The paper is in print in Phys. Rev. C.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Measuring the Radial Component of the Magnetic Field in the Muon g-2 Experiment

A leading systematic error in the muon electric dipole moment (EDM) analysis at Muon g-2 is the presence of radial magnetic fields because they cause indistinguishable effects to the muon spin precession plane from a true EDM measurement. Measuring a non-zero EDM would place a constraint in CP-violation, indicating new physics beyond the Standard Model. The radial field is composed of an applied radial field by the surface correction coils (SCC) and a background radial field due to imperfections in the materials and alignment of magnetic elements. We determine an optimal SCC setting that best minimizes the background radial field by performing a scan at different electro-static quadrupole settings and studying its relation with the vertical beam position and applied radial field. In this talk I will present our results and describe our efforts to design an apparatus outfitted with Hall probes and tilt sensors to directly measure the radial magnetic field as a function of az imuth.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2023

SAM Code Development for Source Term Modeling in Fluoride-salt-cooled High-temperature Reactors

The SAM code is under development and supported by DOE-NE’s Nuclear Energy Advanced Modeling and Simulation program as a modern system-level modeling and simulation tool for advanced non-light water reactor safety analyses. These advanced reactor concepts incorporate novel and improved approaches to achieve safety and economic feasibility. Many concepts leverage higher operating temperatures for improved efficiency with a variety of coolants and structural materials to support those needs. Such design choices may also pose unique radiological source term risks. There are continuous efforts to incorporate new physics and phenomena relevant to advanced reactor concepts, including capabilities to enable system-level source term modeling. The Pebble-Bed Fluoride-salt-cooled High-temperature Reactor (PB-FHR) is a promising candidate among advanced nuclear reactor concepts with its improved passive safety characteristics and high thermal efficiency. In addition to past efforts to support the development and utilization of SAM for PB-FHR safety analysis, the species transport modeling capabilities in SAM have been extended to simulate source term phenomena in concepts like the PB-FHR. The PB-FHR concept utilizes pebble-form TRISO fuel and FLiBe salt coolant to provide robust barriers to the release of almost all fission products and radiological source terms. However, tritium poses a unique radiological risk due to its significant production from neutron interactions with 6 Li and 9 Be in the FLiBe as well as its high mobility at elevated temperatures where it can permeate through structural metals. Secondly, the use of graphite at elevated temperatures poses the risk of oxidation damage to any structural components or fuel pebbles that are exposed to accidental air ingress. This report summarizes progress made in modeling these phenomena in SAM, which leverages the system-level multi-physics thermal hydraulic simulation to support an effective engineering-scale source term modeling capability. A tritium transport model is developed to simulate the various transport pathways in FHR and MSR concepts and is presented through verification and validation examples as well as demonstrations simulating experimental test loops and reference plant FHR models. A graphite oxidation model is also introduced to calculate local oxidation rates and is presented with initial validation results.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2024

Enhancements and Deployment of the TDAQ System for the Mu2e Experiment

The Real Time Processing Systems Division at Fermilab has deployed new features to the Off-The-Shelf Data Acquisition framework (otsdaq) for the Mu2e experiment. The Mu2e experiment will search for the coherent neutrino-less conversion of a muon into an electron in the field of an aluminum nucleus with a sensitivity improvement of 10,000 times over existing limits. Such a charged lepton flavor-violating reaction probes new physics at a scale unavailable at present or planned high-energy colliders. The Mu2e Trigger and Data Acquisition (TDAQ) system uses otsdaq as its online Data Acquisition System (DAQ) framework. otsdaq integrates the artdaq and art frameworks for event transfer, filtering, and processing. otsdaq is a web-based DAQ software suite focusing on flexibility and scalability and provides a multi-user interface accessible through a web browser. artdaq handles the entire data stream, which is read over the peripheral component interconnect express (PCIe) bus to a software filter algorithm that selects events combined with the data flux coming from a cosmic-ray veto (CRV) system. Detector front-ends are configured through the PCIe bus by customized otsdaq plugins. The otsdaq slow controls infrastructure has been further developed using the experimental physics and industrial control system (EPICS) open-source platform for monitoring, controlling, alarming, and archiving. The detector control system (DCS) for Mu2e has been integrated into otsdaq. The production TDAQ and DCS system has been deployed at the experimental hall and is being debugged and optimized for experiment operations. We report on the feature enhancements and deployment of otsdaq for Mu2e.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Search For Low-Mass Quark-Antiquark Resonances Produced With an Initial State Photon at 13 TeV Using the CMS Detector

We present a search for low-mass narrow qq̅ resonances. This search uses data from LHC pp collisions at a center of mass of 13 TeV in Run 2, and corresponds to an integrated luminosity of 137 fb^{-1}, currently using 10\% of data. Utilizing full Run 2 data allows the use of a lower photon pT threshold trigger than a previous analysis performed with only 2016 data, allowing this analysis to be more sensitive to resonances in the low mass region. We require an initial state photon recoiling against the narrow resonance, leading to the resonance having a high transverse momentum. The high pT decay products of the resonance collimate and are reconstructed as a single large jet with an internal two-pronged substructure. A two-pronged dijet score based on the ParticleNet tagger is used to select jets with two-pronged substructure. The background is estimated via a data-driven method using a transfer factor between the distributions which fail and pass the two-pronged substructure requirement. The new physics signal is searched for as a narrow peak excess above the Standard Model backgrounds in the jet mass spectrum.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗