Abstract
The Outreach Cosmic Ray Activities (OCRA) project was created in 2018 within the Italian Istituto Nazionale di Fisica Nucleare (INFN) to offer a platform for all outreach activities focusing ...on cosmic rays within the institute. OCRA now counts 22 of the institute’s divisions all over Italy as members. The project offers activities both for students and teachers. The one activity common to all local groups is the participation in the yearly International Cosmic Day, organized by DESY, inviting high school students to carry out hands-on measurements of the cosmic ray flux and learn about the related physics background. Two students from each division are then selected to participate in the annual OCRA science camp, a three-day full immersion into the life of a physicist. For both teachers and students, the OCRA website https://web.infn.it/OCRA/, offers a series of online laboratories designed both to be used by students individually but also to be offered in the classroom by teachers. A section dedicated to teachers provides ample material to help bring these laboratories to the classroom. The online materials were presented in a course for teachers in spring 2021. In addition to the national efforts, there are also local initiatives of the OCRA member groups: workshops and secondments, science competitions and the development of new detectors for outreach activities offer a multitude of possibilities for students to engage with our researchers and to explore the world of cosmic rays. This article provides an overview on all activities offered by OCRA with a particular focus on the 2022 science camp.
In the direct searches for Weakly Interacting Massive Particles (WIMPs) as Dark Matter candidates, the sensitivity of the detector to the incom- ing particle direction could provide a smoking gun ...signature for an interesting event. The SCENE collaboration firstly suggested the possible directional de- pendence of a dual-phase argon Time Projection Chamber through the columnar recombination effect. The Recoil Directionality project (ReD) within the Global Argon Dark Matter Collaboration aims to characterize the light and charge re- sponse of a liquid Argon dual-phase TPC to neutron-induced nuclear recoils to probe for the hint by SCENE. In this work, the directional sensitivity of the de- tector in the energy range of interest for WIMPs (20-100 keV) is investigated with a data-driven analysis involving a Machine Learning algorithm.
Abstract
Directional sensitivity to nuclear recoils would provide a smoking gun for a possible discovery of dark matter in the form of WIMPs (Weakly Interacting Massive Particles). A hint of ...directional dependence of the response of a dual-phase argon Time Projection Chamber (TPC) was found in the SCENE experiment. Given the potential importance of such a capability in the framework of dark matter searches, a new dedicated experiment, ReD (Recoil Directionality), was designed by the Global Argon Dark Matter Collaboration, in order to scrutinise this hint. A small dual-phase argon TPC was irradiated with neutrons produced by the p(
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Li,
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Be)n reaction using the 15 MV TANDEM accelerator of the INFN - Laboratori Nazionali del Sud, Catania, Italy, so as to produce argon nuclear recoils in the range (20 - 100) keV of interest for dark matter searches. Energy and direction of nuclear recoils are inferred by the detection of the elastically-scattered neutron by a set of scintillation detectors. Events were selected by gating of the associated
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Be, which is detected by a telescope of Si detectors.
The Recoil Directionality (ReD) Experiment Sanfilippo, S; Agnes, P; Albergo, S ...
Journal of physics. Conference series,
11/2022, Letnik:
2374, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Directional sensitivity to nuclear recoils would provide a smoking gun for a possible discovery of dark matter in the form of WIMPs (Weakly Interacting Massive Particles). A hint of directional ...dependence of the response of a dual-phase argon Time Projection Chamber (TPC) was found in the SCENE experiment. Given the potential importance of such a capability in the framework of dark matter searches, a new dedicated experiment, ReD (Recoil Directionality), was designed by the Global Argon Dark Matter Collaboration, in order to scrutinize this hint. Prior to the irradiation with a neutron beam, the ReD TPC underwent a long campaign of characterization and optimization: some selected results are presented in this contribution.
Recoil Directionality Experiment Sanfilippo, S.; Agnes, P.; Arba, M. ...
EPJ Web of Conferences,
2019, Letnik:
209
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Directional sensitivity to nuclear recoils could provide a smoking gun for a possible discovery of dark matter in the form of WIMPs. A hint of directional dependence of the response of a dual-phase ...liquid argon Time Projection Chamber was found in the SCENE experiment. Given the potential importance of such a capability in the frame work of dark matter searches, a new dedicated experiment, ReD (Recoil Directionality), was designed in the framework of the DarkSide Collaboration, in order to scrutinize this hint. This contribution will describe the performance of the detectors achieved during the first test-beam, the current status of ReD and the perspectives for physics measurements during the forthcoming beam-time.
We report on the search for dark matter weakly interacting massive particles (WIMPs) in the mass range below 10 GeV=c2 from the analysis of the entire dataset acquired with a low-radioactivity argon ...target by the DarkSide-50 experiment at Laboratori Nazionali del Gran Sasso. The new analysis benefits from more accurate calibration of the detector response, improved background model, and better determination of systematic uncertainties, allowing us to accurately model the background rate and spectra down to 0.06 keVer. A 90% C.L. exclusion limit for the spin-independent cross section of 3 GeV=c2 mass WIMP on nucleons is set at 6 × 10-43 cm2, about a factor 10 better than the previous DarkSide-50 limit. This analysis extends the exclusion region for spin-independent dark matter interactions below the current experimental constraints in the 1.2, 3.6 GeV=c2 WIMP mass range.
Front-end electronic system for large area photomultipliers readout Bottino, B.; Caminata, A.; Cariello, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2019, Letnik:
936
Journal Article
Recenzirano
We developed a front-end electronic system for large area photomultipliers. Connection to the PMT can be made by a single cable, useful to minimize cabling in a underwater detector. The cabling is ...done in the rear part of the crate to permit easy access to the electronic boards. A front-end board houses 8 channels each one is composed by a preamplifier and a leading edge discriminator. Up to 8 front-end boards can be housed in a crate, giving a modularity of 64 channels. A controller board is needed to setup and monitor the front-end parameters. This board implements also scalers and time to digital converters with time over threshold capability. A standard gigabit ethernet line is used for communication with the outside world. Details on the design and specification of the system is reported together some preliminary measurements done with the prototypes now under test in laboratory.
•Underwater detectors with large number of channels need dedicated data acquisition system.•Compact and modular systems are mandatory to build up the system.•FPGA are always used to have the maximum flexibility in implementing user logic.
Finding unequivocal evidence of dark matter interactions in a particle detector is a major goal of research in physics. Liquid argon time projection chambers offer a path to probe Weakly Interacting ...Massive Particles scattering cross sections on nuclei down to the so-called neutrino floor, in a mass range from a few GeV to hundreds of TeV. Based on the successful operation of the DarkSide-50 detector at LNGS, a new and more sensitive experiment, DarkSide-20k, has been designed and is now under construction. A thorough understanding of the DarkSide-50 detector response and, therefore, of all types of events observed in the detector, is essential for the optimal design of the new experiment. In this article, we report on a specific set of events, namely, standard two-pulse scintillation–ionization signals with a third small amplitude pulse, occurring within the 440μs data acquisition window of standard events. Some of these events are due to the photoionization of the TPC cathode. We compare our results with those published by collaborations using liquid xenon time projection chambers, which observed a similar phenomenon, and, in particular, with a recent paper by the LUX Collaboration (D.S. Akerib et al. Phys.Rev.D 102, 092004 (2020)) From the measured rate of these events, we estimate for the first time the quantum efficiency of the tetraphenyl butadiene deposited on the DarkSide-50 cathode at wavelengths of around 128 nm, in liquid argon. Also, both experiments observe events likely related to the photoionization of impurities in the liquid. The probability of photoelectron emission per unit length turns out to be an order of magnitude lower in DarkSide-50 than in LUX.
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