Modern physics experiments are frequently very complex, relying on multiple simultaneous events to happen in order to obtain the desired result. The experiment control system plays a central role in orchestrating the measurement setup: However, its development is often treated as secondary with respect to the hardware, its importance becoming evident only during the operational phase. Therefore, the AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) collaboration has created a framework for easily coding control systems, specifically targeting atomic, quantum, and antimatter experiments. This framework, called Total Automation of LabVIEW Operations for Science (TALOS), unifies all the machines of the experiment in a single entity, thus enabling complex high-level decisions to be taken, and it is constituted by separate modules, called MicroServices, that run concurrently and asynchronously. This enhances the stability and reproducibility of the system while allowing for continuous integration and testing while the control system is running. The system demonstrated high stability and reproducibility, running completely unsupervised during the night and weekends of the data-taking campaigns. The results demonstrate the suitability of TALOS to manage an entire physics experiment in full autonomy: being open-source, experiments other than the AEgIS experiment can benefit from it.
Graph showing the number of antiprotons captured vs the closure timing of the trap. It clearly shows the presence of a best working point. Closing too fast lets some antiprotons out, and, conversely, closing too slow lets some antiprotons escape after the bounce on the second electrode.
Graph showing the number of antiprotons captured varying the potential of the catching electrodes. This scan characterizes the energy profile of the p's passing through the degrader, and their ratio is in good accordance with our GEANT4 simulations.
Two graphs show the results of the scan over the horizontal and vertical displacements of the antiproton beam (on the left) and the horizontal and vertical angles (see Table 4, after). The color represents the intensity of the signal obtained on the MCP from the annihilations of the trapped antiprotons. The parameter space has been organized in this way, assuming that displacements and angles have independent effects, not for physics reasons, but because scanning over the full parameter space would have been impossible time-wise (10 steps per dimension 4 dimensions x 5 min of duration of the script ~35 days!).
A powerful and robust control system is a crucial, often neglected, pillar of any modern, complex physics experiment that requires the management of a multitude of different devices and their precise time synchronisation. The AEgIS collaboration presents CIRCUS, a novel, autonomous control system optimised for time-critical experiments such as those at CERN's Antiproton Decelerator and, more broadly, in atomic and quantum physics research. Its setup is based on Sinara/ARTIQ and TALOS, integrating the ALPACA analysis pipeline, the last two developed entirely in AEgIS. It is suitable for strict synchronicity requirements and repeatable, automated operation of experiments, culminating in autonomous parameter optimisation via feedback from real-time data analysis. CIRCUS has been successfully deployed and tested in AEgIS; being experiment-agnostic and released open-source, other experiments can leverage its capabilities.
Synchronous voltage ramp-up to 20 V on three high-voltage amplifier channels 10 μs subsequent to the arrival of a common trigger pulse at zero time in the figure. The inset shows a zoom to the shoulder region for a better visualisation of the synchronicity.
A feedback loop uses the uncorrected laser pulse timings (red squares) to calculate the deviation from the user setting (solid black line) over the course of an hour, and corrects the timing of the subsequent desired laser pulse that is used for the actual experiment (blue circles). Independent of short-term to long-term drifts or even sudden jumps, the resulting timing is always close to the desired value.
A feedback loop uses the uncorrected laser pulse timings (red squares) to calculate the deviation from the user setting (solid black line) over the course of an hour, and corrects the timing of the subsequent desired laser pulse that is used for the actual experiment (blue circles). Independent of short-term to long-term drifts or even sudden jumps, the resulting timing is always close to the desired value.
A new algorithm is presented to discriminate reconstructed hadronic decays of tau leptons ($\tau_\mathrm{h}$) that originate from genuine tau leptons in the CMS detector against $\tau_\mathrm{h}$ candidates that originate from quark or gluon jets, electrons, or muons. The algorithm inputs information from all reconstructed particles in the vicinity of a $\tau_\mathrm{h}$ candidate and employs a deep neural network with convolutional layers to efficiently process the inputs. This algorithm leads to a significantly improved performance compared with the previously used one. For example, the efficiency for a genuine $\tau_\mathrm{h}$ to pass the discriminator against jets increases by 10-30% for a given efficiency for quark and gluon jets. Furthermore, a more efficient $\tau_\mathrm{h}$ reconstruction is introduced that incorporates additional hadronic decay modes. The superior performance of the new algorithm to discriminate against jets, electrons, and muons and the improved $\tau_\mathrm{h}$ reconstruction method are validated with LHC proton-proton collision data at $\sqrt{s} =$ 13 TeV.
Decay mode confusion matrix. For a given generated decay mode, the fractions of reconstructed tau_h in different decay modes are given, as well as the fraction of generated tau_h that are not reconstructed. Both the generated and reconstructed tau_h need to fulfil pt > 20 GeV and |eta| < 2.3. The tau_h candidates come from a Z to tau tau event sample with m(tau, tau) > 50 GeV.
Efficiency for quark and gluon jets to pass different tau identification discriminators versus the efficiency for genuine tau_h. The upper two plots are obtained with jets from the W+jets simulated sample and the lower two plots with jets from the tt sample. The left two plots include jets and genuine tau_h with pt < 100 GeV, whereas the right two plots include those with pt > 100 GeV. The working points are indicated as full circles. The efficiency for jets from the W+jets event sample, enriched in quark jets, to pass the discriminators is higher compared to jets from the tt event sample, which has a larger fraction of gluon and b-quark jets. The jet efficiency for a given tau_h efficiency is larger for jets and tau_h with pt < 100 GeV than for those with pt > 100 GeV. Compared with the previously used MVA discriminator, the DEEPTAU discriminator reduces the jet efficiency for a given tau_h efficiency by consistently more than a factor of 1.8, and by more at high tau_h efficiency. The additional gain at high pt comes from the inclusion of updated decay modes in the tau_h reconstruction, as illustrated by the curves for the previously used MVA discriminator but including reconstructed tau_h candidates with additional decay modes.
Efficiency for quark and gluon jets to pass different tau identification discriminators versus the efficiency for genuine tau_h. The upper two plots are obtained with jets from the W+jets simulated sample and the lower two plots with jets from the tt sample. The left two plots include jets and genuine tau_h with pt < 100 GeV, whereas the right two plots include those with pt > 100 GeV. The working points are indicated as full circles. The efficiency for jets from the W+jets event sample, enriched in quark jets, to pass the discriminators is higher compared to jets from the tt event sample, which has a larger fraction of gluon and b-quark jets. The jet efficiency for a given tau_h efficiency is larger for jets and tau_h with pt < 100 GeV than for those with pt > 100 GeV. Compared with the previously used MVA discriminator, the DEEPTAU discriminator reduces the jet efficiency for a given tau_h efficiency by consistently more than a factor of 1.8, and by more at high tau_h efficiency. The additional gain at high pt comes from the inclusion of updated decay modes in the tau_h reconstruction, as illustrated by the curves for the previously used MVA discriminator but including reconstructed tau_h candidates with additional decay modes.
This article reports the measurement of the $^{235}$U-induced antineutrino spectrum shape by the STEREO experiment. 43'000 antineutrinos have been detected at about 10 m from the highly enriched core of the ILL reactor during 118 full days equivalent at nominal power. The measured inverse beta decay spectrum is unfolded to provide a pure $^{235}$U spectrum in antineutrino energy. A careful study of the unfolding procedure, including a cross-validation by an independent framework, has shown that no major biases are introduced by the method. A significant local distortion is found with respect to predictions around $E_\nu \simeq 5.3$ MeV. A gaussian fit of this local excess leads to an amplitude of $A = 12.1 \pm 3.4\%$ (3.5$\sigma$).
Data from Figure 13 – Measured IBD yield spectrum and area-normalized HM-based prediction. Here, error bars inlude only uncorrelated uncertainties, namely statistics, time-evolution systematic, reactor background systematic. This uncorrelated uncertainty is $\sigma_j$ in eqn.(14). The full covariance matrix is provided in another entry.
Total covariance matrix of the measured spectrum, including statistics and all systematic uncertainties. It is denoted $V_\text{pr}$ in eqn.(18).
STEREO Detector Response Matrix, sampled using STEREO's simulation using neutrinos with energy distributed according to HFR's IBD yield prediction. The matrix is given as a 200x22 matrix, with 200 50keV-wide $E_\nu$ bins (centers ranging from 0.05 to 10 MeV) and 22 250keV-wide measured-energy bins corresponding to measured data. The matrix is not normalized; desired normalization (e.g., $\sum_j R_{ij} = e_i$ where $e_i$ is the efficiency) has to be applied before the matrix can be used.
The STEREO experiment is a very short baseline reactor antineutrino experiment. It is designed to test the hypothesis of light sterile neutrinos being the cause of a deficit of the observed antineutrino interaction rate at short baselines with respect to the predicted rate, known as the reactor antineutrino anomaly. The STEREO experiment measures the antineutrino energy spectrum in six identical detector cells covering baselines between 9 and 11 m from the compact core of the ILL research reactor. In this article, results from 179 days of reactor turned on and 235 days of reactor turned off are reported at a high degree of detail. The current results include improvements in the modelling of detector optical properties and the gamma-cascade after neutron captures by gadolinium, the treatment of backgrounds, and the statistical method of the oscillation analysis. Using a direct comparison between antineutrino spectra of all cells, largely independent of any flux prediction, we find the data compatible with the null oscillation hypothesis. The best-fit point of the reactor antineutrino anomaly is rejected at more than 99.9% C.L.
Data from Figure 30 – Relative comparison between the estimated rates of IBD events $A_{l,i}$ (for cell $l$ and energy bin $i$) and the re-normalised no-oscillation model $\phi_i M_{l,i}(\sin^2(2\theta_{ee}) = 0)$ as a function of reconstructed energy $E_\text{rec}$ after a fit to phase-I+II data. Due to less statistics, the highest energy bin is excluded from the oscillation analysis in phase-I. For technical reasons, its value is set equal to zero in this dataset. A full graphical presentation can be downloaded at "Resources" for reference.
Data from Figure 30 – Relative comparison between the estimated rates of IBD events $A_{l,i}$ (for cell $l$ and energy bin $i$) and the fitted no-oscillation model $M_{l,i}(0, 0, \vec{\alpha})~\phi_i$ as a function of reconstructed energy $E_\text{rec}$ after a fit to phase-I+II data. Due to less statistics, the highest energy bin is excluded from the oscillation analysis in phase-I. For technical reasons, its value is set equal to zero in this dataset. A graphical presentation can be downloaded at "Resources" for reference.
Data from Figure 30 – Relative comparison between the estimated rates of IBD events $A_{l,i}$ (for cell $l$ and energy bin $i$) and the fitted no-oscillation model $M_{l,i}(0, 0, \vec{\alpha})~\phi_i$ as a function of reconstructed energy $E_\text{rec}$ after a fit to phase-I+II data. Due to less statistics, the highest energy bin is excluded from the oscillation analysis in phase-I. For technical reasons, its value is set equal to zero in this dataset. A graphical presentation can be downloaded at "Resources" for reference.
The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/$c$ in p-Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both for jet, light nuclei, and electron selection.
Most probable charge deposit signal normalised to that of minimum ionising particles as a function of $\beta\gamma$ for $\pi$, $\it{e}$ test beam (dE/dx). Statistical uncertainties as vertical error bars.
Most probable charge deposit signal normalised to that of minimum ionising particles as a function of $\beta\gamma$ for $\pi$, $\it{e}$ test beam (dE/dx + TR). Statistical uncertainties as vertical error bars.
Most probable charge deposit signal normalised to that of minimum ionising particles as a function of $\beta\gamma$ for $\pi$, $\it{e}$ and proton in pp collisions ($\sqrt{s} = 7$ TeV). Statistical uncertainties as vertical error bars. Uncertainties in momentum and thus $\beta \gamma$ determination are drawn as horizontal error bars.
We perform a low-mass dark matter search using an exposure of 30\,kg$\times$yr with the XENON100 detector. By dropping the requirement of a scintillation signal and using only the ionization signal to determine the interaction energy, we lowered the energy threshold for detection to 0.7\,keV for nuclear recoils. No dark matter detection can be claimed because a complete background model cannot be constructed without a primary scintillation signal. Instead, we compute an upper limit on the WIMP-nucleon scattering cross section under the assumption that every event passing our selection criteria could be a signal event. Using an energy interval from 0.7\,keV to 9.1\,keV, we derive a limit on the spin-independent WIMP-nucleon cross section that excludes WIMPs with a mass of 6\,GeV/$c^2$ above $1.4 \times 10^{-41}$\,cm$^2$ at 90\% confidence level.
WIMP exclusion limit on the spin-independent WIMP-nucleon scattering cross section at 90% confidence level.
Production of K^{+} mesons in charged-current \nu_{\mu} interactions on plastic scintillator (CH) is measured using MINERvA exposed to the low-energy NuMI beam at Fermilab. Timing information is used to isolate a sample of 885 charged-current events containing a stopping K^{+} which decays at rest. The differential cross section in K^{+} kinetic energy, d\sigma/dT_{K}, is observed to be relatively flat between 0 and 500 MeV. Its shape is in good agreement with the prediction by the \textsc{genie} neutrino event generator when final-state interactions are included, however the data rate is lower than the prediction by 15\%.
The predicted $\nu_\mu$ flux per POT for the data included in this analysis.
The differential cross section with respect to $K^+$ kinetic energy $T_{K}$ is given in units of $10^{-39}$ cm$^{2}$ per nucleon per GeV, as well as the total statistical and systematic uncertainties.
The covariance for the flux uncertainty.
Measurements of particle emission from a replica of the T2K 90 cm-long carbon target were performed in the NA61/SHINE experiment at CERN SPS, using data collected during a high-statistics run in 2009. An efficient use of the long-target measurements for neutrino flux predictions in T2K requires dedicated reconstruction and analysis techniques. Fully-corrected differential yields of $\pi^\pm$-mesons from the surface of the T2K replica target for incoming 31 GeV/c protons are presented. A possible strategy to implement these results into the T2K neutrino beam predictions is discussed and the propagation of the uncertainties of these results to the final neutrino flux is performed.
Spectra of positively charged pions at the surface of the T2K replica target, in the polar angle range from 0 to 20 mrad and for longitudinal bin $z1$, as a function of momentum. The normalization is per proton on target.
Spectra of positively charged pions at the surface of the T2K replica target, in the polar angle range from 20 to 40 mrad and for longitudinal bin $z1$, as a function of momentum. The normalization is per proton on target.
Spectra of positively charged pions at the surface of the T2K replica target, in the polar angle range from 40 to 60 mrad and for longitudinal bin $z1$, as a function of momentum. The normalization is per proton on target.
The charge ratio, $R_\mu = N_{\mu^+}/N_{\mu^-}$, for cosmogenic multiple-muon events observed at an under- ground depth of 2070 mwe has been measured using the magnetized MINOS Far Detector. The multiple-muon events, recorded nearly continuously from August 2003 until April 2012, comprise two independent data sets imaged with opposite magnetic field polarities, the comparison of which allows the systematic uncertainties of the measurement to be minimized. The multiple-muon charge ratio is determined to be $R_\mu = 1.104 \pm 0.006 {\rm \,(stat.)} ^{+0.009}_{-0.010} {\rm \,(syst.)} $. This measurement complements previous determinations of single-muon and multiple-muon charge ratios at underground sites and serves to constrain models of cosmic ray interactions at TeV energies.
Efficiency-corrected charge ratios as a function of measured muon multiplicity, $M$.
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