Pedro J. Costa’s scientific contributions

... The first is the electron-to-muon ratio, where one combines the muon content estimation from the WCD [7] and the electromagnetic energy from radio. Recent results of this method are shown in [8]. The second mass-sensitive observable is the depth of shower maximum max . ...

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Highlights from the Auger Engineering Radio Array

... However, the muon content of hadronic showers is scarce at sub-TeV energies. Alternatively, one may analyze the shower footprint patterns on the ground to infer features of the shower development [12][13][14][15]. Hadron-induced showers, unlike pure electromagnetic showers, generate particles with high transverse momentum, causing the shower to spread more laterally and form clusters. ...

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Discriminating sub-TeV gamma and hadron-induced showers through their footprints

... Some level of correlation has been observed between the highest energy cosmic rays and a catalogue of nearby sources [83,84]. Furthermore, at large angular scales, evidence for dipole asymmetry in the arrival direction has been observed at energies above 8×10 18 eV [85]. Based on the data collected by the observatory, related studies of UHE photons [86][87][88][89], UHE neutrinos [90][91][92], UHE neutrons [93,94] and proton-air/proton-proton cross-section [95,96] have been published in the last few years. ...

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Study of cosmic rays by Auger and LHAASO : R&D and Data Analysis of AugerPrime and simulations for LHAASO

... In particular, the composition, made by mostly protons at E ∼ 3 · 10 18 eV, becomes increasingly heavier at larger energies, but the contribution of elements as heavier as Fe remains small. On the other hand, (FD+SD) combined data on N µ correspond to a systematically heavier composition [6]. This is called "muon puzzle" and was already observed in earlier measurements (see e.g. ...

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UHECR measurements and physics at man-made accelerators: mutual constraints

... В частности, в [3] отмечается, что суперпозиция грозового фронта и солнечной бури может вызывать проявление малоизученных быстропротекающих процессов. Можно отметить ряд работ, в которых рассматривается излучение, происходящее во время молний [4][5][6][7][8][9]. Имеется еще рад публикаций, в которых данный вопрос упоминается, в частности в работах Тарасенко [10][11][12][13][14]. Но тут надо отметить, что излучение, зарегистрированное в [10][11][12][13][14], относится к рентгеновскому диапазону. ...

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Спектры радиоактивных изотопологов водяного пара

... The Unified Readout Board (UUB) processes Cherenkov signals from PMTs for efficient data acquisition [9], [10]. A hierarchical trigger system, employing "Threshold" (TH) and "Time-over-Threshold" (ToT) triggers, filters significant muonic events while reducing background noise [11] [12]. ...

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Neural network identification of highly inclined muons in water-Cherenkov particle detectors

... To extend the sensitivity of max to higher zenith angles, where the shower maximum is very far away, radio interferometry [12] can provide the required extra sensitivity. By coherently summing the signals from the radio stations, we reduce the background noise significantly. ...

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Highlights from the Auger Engineering Radio Array

... In this work, we update previous searches for point sources of neutrons using data from the Pierre Auger Observatory [7] by including nine more years of data-taking and extending the zenith range to 0 • < < 80 • , hence covering the declination band −90 • < < 45 • . This corresponds to an increase in exposure from 36,000 km 2 sr yr to 110,000 km 2 sr yr [8]. Additionally, we lowered the energy threshold of the search to th = 0.1 EeV, for particular data sets. ...

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Search for neutrons from Galactic sources with the Pierre Auger Observatory

... For energies above 2 × 10 16 eV, the muon densities measured by the UMD stations of the 433 m array are combined into a single event-wise observable [5]. The relative background contamination ranges between 10 −4 to 10 −7 under the assumption of a pure-proton background, conservative in light of the deficit of muons identified in the air-shower simulations. ...

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The latest result on UHE-photons at the Pierre Auger Observatory

... This yields absolutely calibrated time traces for each antenna and polarisation direction. The calibration chain is illustrated in Fig. 4. A study with an engineering array (AERA) demonstrates the long-term stability of the radio detection technique [39]. Only marginal deviations, compatible with zero have been found over a period of nearly 10 years. ...

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The Radio Detector of the Pierre Auger Observatory