Engineering topics

Ianni, Al.

Publications and source records attributed to Ianni, Al..

12 records

DOE OSTI2025

Review of Particle Physics - Scalar Mesons below 1 GeV

The summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,717 new measurements from 869 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Most of the 120 reviews are updated, including many that are heavily revised. The is divided into two volumes. Volume 1 includes the Summary Tables and 97 review articles. Volume 2 consists of the Particle Listings and contains also 23 reviews that address specific aspects of the data presented in the Listings. The complete (both volumes) is published online on the website of the Particle Data Group () and in a journal. Volume 1 is available in print as the . A with the Summary Tables and essential tables, figures, and equations from selected review articles is available in print, as a web version optimized for use on phones, and as an Android app. The 2024 edition of the Review of Particle Physics should be cited as: S. Navas et al. (Particle Data Group), Phys. Rev. D 110, 030001 (2024)© 20242024

Navas, S. [Universidad de Granada]↗

DOE OSTI2020

Effective field theory interactions for liquid argon target in DarkSide-50 experiment

We reanalize data collected with the DarkSide-50 experiment and recently used to set limits on the spin-independent interaction rate of weakly interacting massive particles (WIMPs) on argon nuclei with an effective field theory framework. The dataset corresponds to a total (16660 ± 270) kg d exposure using a target of low-radioactivity argon extracted from underground sources. We obtain upper limits on the effective couplings of the 12 leading operators in the nonrelativistic systematic expansion. For each effective coupling we set constraints on WIMP-nucleon cross sections, setting upper limits between 2.4×10-45 cm2 and 2.3×10-42 cm2 (8.9 ×10-45 cm2 and 6.0 ×10-42 cm2) for WIMPs of mass of 100 GeV/c2 (1000 GeV/c2) at 90% confidence level.

Agnes, P↗

DOE OSTI2019

Measurement of the ion fraction and mobility of 218Po produced in 222Rn decays in liquid argon

We report measurements of the charged daughter fraction of 218Po as a result of the 222Rn alpha decay, and the mobility of 218Po+ ions, using radon-polonium coincidences from the 238U chain identified in 532 live-days of DarkSide-50 WIMP-search data. The fraction of 218Po that is charged is found to be 0.37 ± 0.03 and the mobility of 218Po+ is (8.6 ± 0.1) × 10-4 cm2/Vs.

Agnes, P↗

DOE OSTI2018

Constraints on Sub-GeV Dark-Matter–Electron Scattering from the DarkSide-50 Experiment

Here, we present new constraints on sub-GeV dark matter particles scattering off electrons based on 6780.0 kg d of data collected with the DarkSide-50 dual-phase argon time projection chamber. This analysis uses electroluminescence signals due to ionized electrons extracted from the liquid argon target. The detector has a very high trigger probability for these signals, allowing for an analysis threshold of three extracted electrons, or approximately 0.05 keVee. We calculate the expected recoil spectra for dark matter-electron scattering in argon and, under the assumption of momentum-independent scattering, improve upon existing limits from XENON10 for dark-matter particles with masses between 30 and 100 MeV/c 2 .

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2018

Low-mass Dark Matter Search with the DarkSide-50 Experiment

We present the results of a search for dark matter WIMPs in the mass range below 20 GeV/c^2 using a target of low-radioactivity argon. The data were obtained using the DarkSide-50 apparatus at Laboratori Nazionali del Gran Sasso (LNGS). The analysis is based on the ionization signal, for which the DarkSide-50 time projection chamber is fully efficient at 0.1 keVee. The observed rate in the detector at 0.5 keVee is about 1.5 events/keVee/kg/day and is almost entirely accounted for by known background sources. We obtain a 90% C.L. exclusion limit above 1.8 GeV/c^2 for the spin-independent cross section of dark matter WIMPs on nucleons, extending the exclusion region for dark matter below previous limits in the range 1.8-6 GeV/c^2.

Agnes, P↗

DOE OSTI2017

CALIS—A CALibration Insertion System for the DarkSide-50 dark matter search experiment

This paper describes the design, fabrication, commissioning and use of a CALibration source Insertion System (CALIS) in the DarkSide-50 direct dark matter search experiment. CALIS deploys radioactive sources into the liquid scintillator veto to characterize the detector response and detection efficiency of the DarkSide-50 Liquid Argon Time Projection Chamber, and the surrounding 30 t organic liquid scintillator neutron veto. It was commissioned in September 2014 and has been used successfully in several gamma and neutron source campaigns since then. A description of the hardware and an excerpt of calibration analysis results are given below.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2017

The DarkSide experiment: Present status and future

Here, DarkSide is a multi-stage program devoted to direct searches of Dark Matter particles with detectors based on double phase liquid Argon Time Projection Chamber. The DarkSide-50 setup is running underground at the Laboratori Nazionali del Gran Sasso. First it was operated with Atmospheric Argon and during that run (1422 ± 67) kg×d of truly background-free exposure has been accumulated. Obtained data made it possible to set a 90% C.L. upper limit on the WIMP-nucleon cross section of 6.1 × 10 –44 cm 2 (for a WIMP mass of 100 GeV/c 2 ). Presently the detector is filled with Underground Argon, which is depleted in 39 Ar by a factor of (1.4 ± 0.2)×10 3 with respect to Atmospheric Argon. Acquired so far (2616 ± 43) kg×d (71 live days) in combination with the data from the Atmospheric Argon run give us the 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section of 2.0×10 –44 cm 2 for a WIMP mass of 100 GeV/c 2 . Up to date this is the best limit obtained with an argon target.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2017

The DarkSide-50 Experiment: a Liquid Argon Target for Dark Matter Particles

The DarkSide-50 experiment, located at the “Laboratori Nazionali del Gran Sasso (INFN)”, is based on low-radioactivity argon double phase time projection chamber, surrounded by an active liquid scintillator veto, designed for the zero background achievement. The liquid argon features sufficient self shielding and easy scalability to multi-tons scale. The impressive reduction of the 39 Ar isotope (compared to the atmospheric argon), along with the excellent pulse shape discrimination, make this technology a possible candidate for the forthcoming generation of multi-ton Dark Matter experiments.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2016

Current Status of the dark matter experiment DarkSide-50

DarkSide-50 is a dark matter direct search experiment at LNGS, searching for rare nuclear recoils possibly induced by WIMPs. It has two nested vetoes and a dual phase liquid argon TPC as dark matter detector. Key features of this experiment are the use of underground argon as radio-pure target and of muon and neutron active vetoes to suppress the background. The first data-taking campaign was running from November 2013 to April 2015 with an atmospheric argon target and a reduced efficiency neutron veto due to internal contamination. However, an upper limit on the WIMP-nucleon cross section of 6.1×10 -44 cm 2 at 90% CL was obtained for a WIMP mass of 100 GeV/c 2 and an exposure of (1422 ± 67) kg·d. At present DarkSide-50 started a 3 years run, intended to be background-free because the neutron veto was successfully recovered and underground argon replaced the atmospheric one. Additionally calibration campaigns for both the TPC and the neutron veto were completed. Thanks to the good performance of the background rejection, the results obtained so far suggest the scalability of DarkSide-50 to a ton-scale detector, which will play a key role into the dark matter search scenario.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2016

A first walk on the DarkSide

DarkSide-50 (DS-50) at Gran Sasso underground laboratory (LNGS), Italy, is a direct dark matter search experiment based on a TPC with liquid argon. DS-50 has completed its first dark matter run using atmospheric argon as target. Here, the DS-50 detector performances and the results of the first physics run are reviewed in this proceeding.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

DOE OSTI2016

Results From the First Use of Low Radioactivity Argon in a Dark Matter Search

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using a two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar39 at a level reduced by a factor (1.4±0.2)×103 relative to atmospheric argon. We report a background-free null result from (2616±43) kg d of data, accumulated over 70.9 live days. When combined with our previous search using an atmospheric argon, the 90% C.L. upper limit on the WIMP-nucleon spin-independent cross section, based on zero events found in the WIMP search regions, is 2.0×10-44 cm2 (8.6×10-44 cm2, 8.0×10-43 cm2) for a WIMP mass of 100 GeV/c2 (1 TeV/c2, 10 TeV/c2).

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2016

The DarkSide project

DarkSide is a graded experimental project based on radiopure argon, and is now, and will be, used in direct dark matter searches. The present DarkSide-50 detector, operating at the Gran Sasso National Laboratory, is a dual-phase, 50 kg, liquid argon time-projection-chamber surrounded by an active liquid scintillator veto. It is designed to be background free in 3 years of operation. DS-50 performances, when filled with atmospheric argon, are reported. However DS-50 filled with underground argon, shows impressive reduction of the 39Ar isotope. The application of this powerful technology in a future generation of the DarkSide program is discussed.

Agnes, P.↗