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Galaxy Clusters Discovered via the Thermal Sunyaev-Zel'dovich Effect in the 500-square-degree SPTpol Survey
No full textWe present a catalog of 689 galaxy cluster candidates detected at significance \xi>4 via their thermal Sunyaev-Zel'dovich (SZ) effect signature in 95 and 150 GHz data from the 500-square-degree SPTpol survey. We use optical and infrared data from the Dark Energy Camera and the Wide-field Infrared Survey Explorer (WISE) and \spitzer satellites, to confirm 544 of these candidates as clusters with purity. The sample has an approximately redshift-independent mass threshold at redshift z>0.25 and spans 1.5 \times 10^{14} < M_{500c} < 9.1 \times 10^{14}M_\odot/h_{70} and . We use external radio data from the Sydney University Molonglo Sky Survey (SUMSS) to estimate contamination to the SZ signal from synchrotron sources. The contamination reduces the recovered by a median value of 0.032, or of the threshold value, and of candidates have a predicted contamination greater than . With the exception of a small number of systems (<1\%), an analysis of clusters detected in single-frequency 95 and 150 GHz data shows no significant contamination of the SZ signal by emission from dusty or synchrotron sources. This cluster sample will be a key component in upcoming astrophysical and cosmological analyses of clusters. The SPTpol millimeter-wave maps and associated data products used to produce this sample are available at https://pole.uchicago.edu/public/data/sptpol_500d_clusters/index.html, and the NASA LAMBDA website. An interactive sky server with the SPTpol maps and Dark Energy Survey data release 2 images is also available at NCSA https://skyviewer.ncsa.illinois.edu
Helium identification with LHCb
No full textThe identification of helium nuclei at LHCb is achieved using a method based onmeasurements of ionisation losses in the silicon sensors and timing measurements in the OuterTracker drift tubes. The background from photon conversions is reduced using the RICH detectorsand an isolation requirement. The method is developed using pp collision data at√(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, correspondingto an integrated luminosity of 5.5 fb. A total of around 10 helium and antiheliumcandidates are identified with negligible background contamination. The helium identificationefficiency is estimated to be approximately 50% with a corresponding background rejectionrate of up to (10). These results demonstrate the feasibility of a richprogramme of measurements of QCD and astrophysics interest involving light nuclei
Probing bad theories with the dualization algorithm. Part I
No full textRecently an algorithm to build SL(2, ℤ) duals, including mirror duals, of 3d = 4 quiver theories and their 4d = 1 uplift has been introduced. In this work we use this new tool to study the so-called bad theories. Our approach allows us to determine exactly indices/partition functions for generic values of fugacities/real mass and FI parameters revealing their surprising feature: the 4d index/3d partition function of a bad theory behaves as a sum of distributions rather than an ordinary function of the deformation parameters. We focus on the bad SQCD, with U(N) gauge group in 3d and USp(2N) in 4d, while in an upcoming paper we will consider linear quivers which, in the 3d case, have both unitary and special unitary bad nodes
The q moments in inclusive semileptonic B decays
No full textWe compute the first moments of the q distribution in inclusive semileptonic B decays as functions of the lower cut on q, confirming a number of results given in the literature and adding the BLM contributions. We then include the q-moments recently measured by Belle and Belle II in a global fit to the moments. The new data are compatible with the other measurements and slightly decrease the uncertainty on the nonperturbative parameters and on |V|. Our updated value is |V| = (41.97 ± 0.48) × 10
Comparing Recent Pulsar Timing Array Results on the Nanohertz Stochastic Gravitational-wave Background
No full textThe Australian, Chinese, European, Indian, and North American pulsar timing array (PTA) collaborations recently reported, at varying levels, evidence for the presence of a nanohertz gravitational-wave background (GWB). Given that each PTA made different choices in modeling their data, we perform a comparison of the GWB and individual pulsar noise parameters across the results reported from the PTAs that constitute the International Pulsar Timing Array (IPTA). We show that despite making different modeling choices, there is no significant difference in the GWB parameters that are measured by the different PTAs, agreeing within 1σ. The pulsar noise parameters are also consistent between different PTAs for the majority of the pulsars included in these analyses. We bridge the differences in modeling choices by adopting a standardized noise model for all pulsars and PTAs, finding that under this model there is a reduction in the tension in the pulsar noise parameters. As part of this reanalysis, we "extended" each PTA's data set by adding extra pulsars that were not timed by that PTA. Under these extensions, we find better constraints on the GWB amplitude and a higher signal-to-noise ratio for the Hellings–Downs correlations. These extensions serve as a prelude to the benefits offered by a full combination of data across all pulsars in the IPTA, i.e., the IPTA's Data Release 3, which will involve not just adding in additional pulsars but also including data from all three PTAs where any given pulsar is timed by more than a single PTA
Design and performance of the field cage for the XENONnT experiment
No full textThe precision in reconstructing events detected in a dual-phase time projection chamber depends on an homogeneous and well understood electric field within the liquid target. In the XENONnT TPC the field homogeneity is achieved through a double-array field cage, consisting of two nested arrays of field shaping rings connected by an easily accessible resistor chain. Rather than being connected to the gate electrode, the topmost field shaping ring is independently biased, adding a degree of freedom to tune the electric field during operation. Two-dimensional finite element simulations were used to optimize the field cage, as well as its operation. Simulation results were compared to calibration data. This comparison indicates an accumulation of charge on the panels of the TPC which is constant over time, as no evolution of the reconstructed position distribution of events is observed. The simulated electric field was then used to correct the charge signal for the field dependence of the charge yield. This correction resolves the inconsistent measurement of the drift electron lifetime when using different calibrations sources and different field cage tuning voltages
Gestione e operatività dei database per le nuove applicazioni della Direzione Sistemi Informativi
Get PDF<p>La modernizzazione dei database, necessaria all’evoluzione di alcuni applicativi verso l’architettura a microservizi, è stata un momento di svolta per il servizio Database dell'Ufficio Sviluppo e Gestione Strategica dell’Infrastruttura. Una svolta tecnologica, organizzativa e di sostenibilità economica basata sulla possibilità di esplorare soluzioni Open Source con cui superare alcuni limiti del modello commerciale, come ad esempio l'indipendenza da una soluzione Oracle, e allo stesso tempo validare l’inclusione nella piattaforma, alla base di sviluppo e gestione dell’Infrastruttura della Direzione Sistemi Informativi (con i suoi servizi e le buone pratiche), di un ulteriore tassello con cui gestire i dati strutturati e non strutturati generati all’interno dell’ecosistema degli applicativi.</p>\n\n<p>In questa nota interna viene descritto, evidenziandone architettura e operatività, come le due tecnologie di database pensate rispettivamente per gestire dati di tipo SQL e NoSQL siano state introdotte all’interno della piattaforma e integrate nel contesto di efficienza operativa della piattaforma stessa.</p>
Radioisotope production using lasers: From basic science to applications
No full textThe discovery of chirped pulse amplification has led to great improvements in laser technology, enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometers. Protons with energies of tens of MeV can be accelerated using, for instance, target normal sheath acceleration and focused on secondary targets. Under such conditions, nuclear reactions can occur, with the production of radioisotopes suitable for medical application. The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators. In this paper, we study the production of 67Cu, 63Zn, 18F, and 11C, which are currently used in positron emission tomography and other applications. At the same time, we study the reactions 10B(p,α)7Be and 70Zn(p,4n)67Ga to put further constraints on the proton distributions at different angles, as well as the reaction 11B(p,α)8Be relevant for energy production. The experiment was performed at the 1 PW laser facility at Vega III in Salamanca, Spain. Angular distributions of radioisotopes in the forward (with respect to the laser direction) and backward directions were measured using a high purity germanium detector. Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera [Nucl. Instrum. Methods Phys. Res., Sect. A 637, 164–170 (2011)]
A measurement of ∆Γ
No full textUsing a dataset corresponding to 9 fb of integrated luminosity collected with the LHCb detector between 2011 and 2018 in proton-proton collisions, the decay-time distributions of the decay modes and are studied. The decay-width difference between the light and heavy mass eigenstates of the meson is measured to be ∆Γ = 0.087 ± 0.012 ± 0.009 ps, where the first uncertainty is statistical and the second systematic.[graphic not available: see fulltext
Workshop summary: Kaons@CERN 2023
No full textKaon physics is at a turning point – while the rare-kaon experiments NA62 and KOTO are in full swing, the end of their lifetime is approaching and the future experimental landscape needs to be defined. With HIKE, KOTO-II and LHCb-Phase-II on the table and under scrutiny, it is a very good moment in time to take stock and contemplate about the opportunities these experiments and theoretical developments provide for particle physics in the coming decade and beyond. This paper provides a compact summary of talks and discussions from the Kaons@CERN 2023 workshop, held in September 2023 at CERN