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Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory
No full textWe show, for the first time, radio measurements of the depth of shower maximum (Xmax) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio Xmax resolution as a function of energy and demonstrate the ability to make competitive high-resolution Xmax measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments
Estimate of background baseline and upper limit on the chiral magnetic effect in isobar collisions at <math><mrow><msqrt><msub><mi>s</mi><mrow><mi>N</mi><mi>N</mi></mrow></msub></msqrt><mo>=</mo><mn>200</mn></mrow></math> GeV at the BNL Relativistic Heavy Ion Collider
No full textFor the search of the chiral magnetic effect (CME), STAR previously presented the results from isobar collisions (Ru4496+Ru4496, Zr4096+Zr4096) obtained through a blind analysis. The ratio of results in Ru+Ru to Zr+Zr collisions for the CME-sensitive charge-dependent azimuthal correlator (Δγ), normalized by elliptic anisotropy (v2), was observed to be close to but systematically larger than the inverse multiplicity ratio. The background baseline for the isobar ratio, Y=(Δγ/v2)Ru(Δγ/v2)Zr, is naively expected to be (1/N)Ru(1/N)Zr; however, genuine two- and three-particle correlations are expected to alter it. We estimate the contributions to Y from those correlations, utilizing both the isobar data and hijing simulations. After including those contributions, we arrive at a final background baseline for Y, which is consistent with the isobar data. We extract an upper limit for the CME fraction in the Δγ measurement of approximately 10% at a 95% confidence level on in isobar collisions at sNN=200GeV, with an expected 15% difference in their squared magnetic fields
Il diritto di ripubblicazione da PlanS ai giorni nostri: memorie e pensieri sparsi
Get PDF<p>Presentazione IX convegno AISA Pisa 2024</p>
Solar neutrino measurements using the full data period of Super-Kamiokande-IV
No full textAn analysis of solar neutrino data from the fourth phase of Super-Kamiokande (SK-IV) from October 2008 to May 2018 is performed and the results are presented. The observation time of the dataset of SK-IV corresponds to 2970 days and the total live time for all four phases is 5805 days. For more precise solar neutrino measurements, several improvements are applied in this analysis: lowering the data acquisition threshold in May 2015, further reduction of the spallation background using neutron clustering events, precise energy reconstruction considering the time variation of the PMT gain. The observed number of solar neutrino events in 3.49–19.49 MeV electron kinetic energy region during SK-IV is 65,443-388+390(stat.)±925(syst.) events. Corresponding B8 solar neutrino flux is (2.314±0.014(stat.)±0.040(syst.))×106 cm-2 s-1, assuming a pure electron-neutrino flavor component without neutrino oscillations. The flux combined with all SK phases up to SK-IV is (2.336±0.011(stat.)±0.043(syst.))×106 cm-2 s-1. Based on the neutrino oscillation analysis from all solar experiments, including the SK 5805 days dataset, the best-fit neutrino oscillation parameters are sin2θ12,solar=0.306±0.013 and Δm21,solar2=(6.10-0.81+0.95)×10-5 eV2, with a deviation of about 1.5σ from the Δm212 parameter obtained by KamLAND. The best-fit neutrino oscillation parameters obtained from all solar experiments and KamLAND are sin2θ12,global=0.307±0.012 and Δm21,global2=(7.50-0.18+0.19)×10-5 eV2
Study of decays
No full textA study of decays is reported using proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb. The decay is observed for the first time, with a significance exceeding seven standard deviations. The relative branching fraction with respect to the decay is measured to bewhere the first uncertainty is statistical, the second is systematic, and the third is due to the knowledge of the χ→ J/ψγ branching fraction. No significant signal is observed and an upper limit for the relative branching fraction for the and decays of \frac{{\mathcal{B}}_{B_c^{+}\to {\chi}_{c1}{\pi}^{+}}}{{\mathcal{B}}_{B_c^{+}\to {\chi}_{c2}{\pi}^{+}}}=<0.49 is set at the 90% confidence level.[graphic not available: see fulltext
Neural network time-series classifiers for gravitational-wave searches in single-detector periods
No full textThe search for gravitational-wave (GW) signals is limited by non-Gaussian transient noises that mimic astrophysical signals. Temporal coincidence between two or more detectors is used to mitigate contamination by these instrumental glitches. However, when a single detector is in operation, coincidence is impossible, and other strategies have to be used. We explore the possibility of using neural network classifiers and present the results obtained with three types of architectures: convolutional neural network, temporal convolutional network, and inception time. The last two architectures are specifically designed to process time-series data. The classifiers are trained on a month of data from the LIGO Livingston detector during the first observing run (O1) to identify data segments that include the signature of a binary black hole merger. Their performances are assessed and compared. We then apply trained classifiers to the remaining three months of O1 data, focusing specifically on single-detector times. The most promising candidate from our search is 4 January 2016 12:24:17 UTC. Although we are not able to constrain the significance of this event to the level conventionally followed in GW searches, we show that the signal is compatible with the merger of two black holes with masses and at the luminosity distance of
Booking: un software per la prenotazione delle risorse dell'ente
Get PDF<p>Progettazione e sviluppo di un software per la prenotazione delle risorse dell’ente che richiedono un workflow approvativo (semplice o complesso) come la prenotazione di fa- cility per esperimenti e aule per conferenze. Lo scopo del software consiste nell’informa- tizzare tutti i processi di business1 applicati alla prenotazione di una determinata risorsa e nell’eliminazione dei processi cartacei non tracciati, garantendo i principi di autentica- zione e autorizzazione in base ai ruoli che l’INFN assegna ai singoli utenti. Attraverso la definizione del workflow e` possibile configurare, oltre al normale flusso procedurale, timer, sotto workflow, invio di email scadenzate e attivare procedure custom come l’in- vio di comandi ad apparecchiature elettroniche. Il core del progetto e` basato sull’utilizzo della notazione BPMN per descrivere i workflow legati alle prenotazioni delle risorse e all’implementazione di un orchestratore per gestirne il ciclo di vita. A differenza di altri strumenti, la notazione BPMN permette di definire un workflow senza la scrittura di co- dice con un linguaggio di programmazione ma con una definizione grafica che facilita la gestione di tutto il processo di prenotazione. E’ stata anche sviluppata un’applicazione web che attraverso una GUI guida l’utente e gli amministratori nel processo di creazione e prenotazione delle risorse. Al momento il software e` in uso per la prenotazione della Beam Test Facility dei LNF e della Labec Facility della sezione di Firenze.</p>
Inferring Fundamental Spacetime Symmetries with Gravitational-Wave Memory: From LISA to the Einstein Telescope
No full textWe revisit gravitational wave (GW) memory as the key to measuring spacetime symmetries, extending beyond its traditional role in GW searches. In particular, we show how these symmetries may be probed via displacement and spin memory observations, respectively. We further find that the Einstein Telescope's (ET) sensitivity enables constraining the strain amplitude of a displacement memory to 2% and that of spin memory to 22%. Finally, we point out that neglecting memory could lead to an overestimation of measurement uncertainties for parameters of binary black hole (BBH) mergers by about 10% in ET
Exact approaches on the string worldsheet
No full textWe review different exact approaches to string theory. In the context of the Green–Schwarz superstring, we discuss the action in curved backgrounds and its supercoset formulation, with particular attention to superstring backgrounds of the AdS type supported by both Ramond–Ramond and Neveu–Schwarz–Neveu–Schwarz fluxes. This is the basis for the discussion of classical integrability, of worldsheet-scattering factorisation in the uniform lightcone gauge, and eventually of the string spectrum through the mirror thermodynamic Bethe ansatz, which for AdS backgrounds was only derived and analysed very recently. We then illustrate some aspects of the Ramond–Neveu–Schwarz string, and introduce the formalism of Berkovits–Vafa–Witten, which has seen very recent applications to AdS physics, which we also briefly review. Finally, we present the relation between M-theory in the discrete lightcone quantisation and decoupling limits of string theory that exhibit non-relativistic behaviors, highlighting the connection with integrable deformations, as well as the relation between spin-matrix theory and Landau–Lifshitz models.This review is based on lectures given at the Young Researchers Integrability School and Workshop 2022 'Taming the string worldsheet' at NORDITA, Stockholm
Cosmological constraints from the tomography of DES-Y3 galaxies with CMB lensing from ACT DR4
No full textWe present a measurement of the cross-correlation between the MagLim galaxies selected from the Dark Energy Survey (DES) first three years of observations (Y3) and cosmic microwave background (CMB) lensing from the Atacama Cosmology Telescope (ACT) Data Release 4 (DR4), reconstructed over ∼ 436 deg of the sky. Our galaxy sample, which covers ∼ 4143 deg, is divided into six redshift bins spanning the redshift range of 0.20<z<1.05. We adopt a blinding procedure until passing all consistency and systematics tests. After imposing scale cuts for the cross-power spectrum measurement, we reject the null hypothesis of no correlation at 9.1σ. We constrain cosmological parameters from a joint analysis of galaxy and CMB lensing-galaxy power spectra considering a flat ΛCDM model, marginalized over 23 astrophysical and systematic nuisance parameters. We find the clustering amplitude S ≡ σ(Ωm/0.3) = 0.75. In addition, we constrain the linear growth of cosmic structure as a function of redshift. Our results are consistent with recent DES Y3 analyses and suggest a preference for a lower S compared to results from measurements of CMB anisotropies by the Planck satellite, although at a mild level (< 2σ) of statistical significance