48 research outputs found
The E302 instability-versus-efficiency experiment at FACET-II
We discuss plans for the E302 instability-efficiency experiment, starting in
2024 at the recently upgraded FACET-II facility at SLAC National Accelerator
Laboratory. The beam-breakup instability will be the main area of study for the
E302 experiment. With the imaging spectrometer at FACET-II, we introduce a
novel technique for observing and quantifying the amplitude growth of the
trailing bunch due to the transverse instability. Using the transverse position
on the spectrometer screen and the transfer matrix of the magnetic lattice used
for the spectrometer, we aim to extract a - charge distribution that can
be used to quantify the amplitude of the beam. By varying the trailing bunch's
charge and, hence, the beam loading of the accelerating field, we aim to adjust
the wake-to-beam power transfer efficiency in the E302 experiment. We plan to
quantify the amplitude for different configurations of the beam charge and,
hence, investigate the relationship between the beam-breakup instability and
efficiency. We use a combination of particle-in-cell (PIC) codes to simulate a
beam-driven plasma wakefield accelerator from start-to-end with a FACET-II-like
spectrometer and demonstrate the methodology that will be used for the
instability studies at the E302 experiment.Comment: 9 pages, 9 figures, conference proceeding for the 6th European
Advanced Accelerator Concepts workshop (EAAC2023), 17-23 September 202
Multidifferential cross section measurements of νμ -argon quasielasticlike reactions with the MicroBooNE detector
We report on a flux-integrated multidifferential measurement of charged-current muon neutrino scattering on argon with one muon and one proton in the final state using the Booster Neutrino Beam and MicroBooNE detector at Fermi National Accelerator Laboratory. The data are studied as a function of various kinematic imbalance variables and of a neutrino energy estimator, and are compared to a number of event generator predictions. We find that the measured cross sections in different phase-space regions are sensitive to nuclear effects. Our results provide precision data to test and improve the neutrino-nucleus interaction models needed to perform high-accuracy oscillation analyses. Specific regions of phase space are identified where further model refinements are most needed
First Double-Differential Measurement of Kinematic Imbalance in Neutrino Interactions with the MicroBooNE Detector
We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved
First demonstration of O (1 ns) timing resolution in the MicroBooNE liquid argon time projection chamber
MicroBooNE is a neutrino experiment located in the Booster Neutrino Beamline (BNB) at Fermilab, which collected data from 2015 to 2021. MicroBooNE's liquid argon time projection chamber (LArTPC) is accompanied by a photon detection system consisting of 32 photomultiplier tubes used to measure the argon scintillation light and determine the timing of neutrino interactions. Analysis techniques combining light signals and reconstructed tracks are applied to achieve a neutrino interaction time resolution of O(1 ns). The result obtained allows MicroBooNE to access the nanosecond beam structure of the BNB for the first time. The timing resolution achieved will enable significant enhancement of cosmic background rejection for all neutrino analyses. Furthermore, the ns timing resolution opens new avenues to search for long-lived-particles such as heavy neutral leptons in MicroBooNE, as well as in future large LArTPC experiments, namely the SBN program and DUNE
Search for heavy neutral leptons in electron-positron and neutral-pion final states with the MicroBooNE detector
We present the first search for heavy neutral leptons (HNL) decaying into
or final states in a liquid-argon time projection
chamber using data collected with the MicroBooNE detector. The data were
recorded synchronously with the NuMI neutrino beam from Fermilab's Main
Injector corresponding to a total exposure of protons on
target. We set upper limits at the confidence level on the mixing
parameter in the mass ranges MeV for the channel and MeV for
the channel, assuming . These limits represent the most stringent constraints in the
mass range MeV and the first constraints from a direct
search for decays.Comment: Version as accepted by Physical Review Letters, some presentational
changes and updated references, no changes to result
Differential cross section measurement of charged current interactions without final-state pions in MicroBooNE
In this letter we present the first measurements of an exclusive electron
neutrino cross section with the MicroBooNE experiment using data from the
Booster Neutrino Beamline at Fermilab. These measurements are made for a
selection of charged-current electron neutrinos without final-state pions.
Differential cross sections are extracted in energy and angle with respect to
the beam for the electron and the leading proton. The differential cross
section as a function of proton energy is measured using events with protons
both above and below the visibility threshold. This is done by including a
separate selection of electron neutrino events without reconstructed proton
candidates in addition to those with proton candidates. Results are compared to
the predictions from several modern generators, and we find the data agrees
well with these models. The data shows best agreement, as quantified by
-value, with the generators that predict a lower overall cross section, such
as GENIE v3 and NuWro
Measurement of neutral current single production on argon with the MicroBooNE detector
We report the first measurement of production in neutral current (NC)
interactions on argon with average neutrino energy of ~GeV. We use
data from the MicroBooNE detector's 85-tonne active volume liquid argon time
projection chamber situated in Fermilab's Booster Neutrino Beam and exposed to
protons on target for this measurement. Measurements of NC
events are reported for two exclusive event topologies without charged
pions. Those include a topology with two photons from the decay of the
and one proton and a topology with two photons and zero protons. Flux-averaged
cross-sections for each exclusive topology and for their semi-inclusive
combination are extracted (efficiency-correcting for two-plus proton final
states), and the results are compared to predictions from the \textsc{genie},
\textsc{neut}, and \textsc{NuWro} neutrino event generators. We measure cross
sections of (syst) (stat), ,
and for the
semi-inclusive NC, exclusive NC+1p, and exclusive NC+0p
processes, respectively.Comment: 16 pages, 14 figures, 2 table
First measurement of quasi-elastic baryon production in muon anti-neutrino interactions in the MicroBooNE detector
We present the first measurement of the cross section of Cabibbo-suppressed
baryon production, using data collected with the MicroBooNE detector
when exposed to the neutrinos from the Main Injector beam at the Fermi National
Accelerator Laboratory. The data analyzed correspond to
protons on target of neutrino mode running and protons on
target of anti-neutrino mode running. An automated selection is combined with
hand scanning, with the former identifying five candidate production
events when the signal was unblinded, consistent with the GENIE prediction of
events. Several scanners were employed, selecting between three
and five events, compared with a prediction from a blinded Monte Carlo
simulation study of events. Restricting the phase space to only
include baryons that decay above MicroBooNE's detection thresholds,
we obtain a flux averaged cross section of
cmAr, where statistical and systematic uncertainties are combined
First Measurement of Differential Cross Sections for Muon Neutrino Charged Current Interactions on Argon with a Two-proton Final State in the MicroBooNE Detector
We present the first measurement of differential cross sections for
charged-current muon neutrino interactions on argon with one muon, two protons,
and no pions in the final state. Such interactions leave the target nucleus in
a two-particle two-hole state; these states are of great interest, but
currently there is limited information about their production in
neutrino-nucleus interactions. Detailed investigations of the production of
two-particle two-hole states are vital to support upcoming experiments
exploring the nature of the neutrino, and the development of the liquid-argon
time-projection-chamber has made possible the isolation of such final states.
The opening angle between the two protons, the angle between the total proton
momentum and the muon, and the total transverse momentum of the final state
system are sensitive to the underlying physics processes as embodied in a
variety of models. Realistic initial-state momentum distributions are shown to
be important in reproducing the data.Comment: To be submitted to PR
Measurement of triple-differential inclusive muon-neutrino charged-current cross section on argon with the MicroBooNE detector
We report the first measurement of the differential cross section
for inclusive
muon-neutrino charged-current scattering on argon. This measurement utilizes
data from 6.4 protons on target of exposure collected using the
MicroBooNE liquid argon time projection chamber located along the Fermilab
Booster Neutrino Beam with a mean neutrino energy of approximately 0.8~GeV. The
mapping from reconstructed kinematics to truth quantities, particularly from
reconstructed to true neutrino energy, is validated by comparing the
distribution of reconstructed hadronic energy in data to that of the model
prediction in different muon scattering angle bins after conditional constraint
from the muon momentum distribution in data. The success of this validation
gives confidence that the missing energy in the MicroBooNE detector is
well-modeled in simulation, enabling the unfolding to a triple-differential
measurement over muon momentum, muon scattering angle, and neutrino energy. The
unfolded measurement covers an extensive phase space, providing a wealth of
information useful for future liquid argon time projection chamber experiments
measuring neutrino oscillations. Comparisons against a number of commonly used
model predictions are included and their performance in different parts of the
available phase-space is discussed