This paper reports a brief introduction to Deep Underground Laboratories (DULs) and the connection they have with research on biology in extreme environments and the effect of radiation in life. ...Presently, there are 14 DULs in operation worldwide. Although the main research activity in these infrastructures concerns the search for rare events in astroparticle physics and neutrino physics, DULs offer a unique opportunity to undertake experiments in astrobiology and biology in extreme environments. This is the main motivation of Deep Underground Laboratory Integrated Activity in biology (DULIA-bio) 2019 Workshop, which was held at the Gran Sasso (Italy) underground laboratory. This paper aims to give an introduction to the subject of the Workshop by reviewing the main features of DULs.
Ongoing social restrictions, including social distancing and lockdown, adopted by many countries to inhibit spread of the the COVID-19 epidemic, must attempt to find a trade-off between induced ...economic damage, healthcare system collapse, and the costs in terms of human lives. Applying and removing restrictions on a system with a given latency as represented by an epidemic outbreak (and formally comparable with mechanical inertia), may create critical instabilities, overshoots, and strong oscillations in the number of infected people around the desirable set-point, defined in a practical way as the maximum number of hospitalizations acceptable by a given healthcare system. A good understanding of the system reaction to any change of the input control variable can be reasonably achieved using a proportional–integral–derivative controller (PID), which is a widely used technique in various physics and technological applications. In this paper, this control theory to is proposed to be applied epidemiology, to understand the reaction of COVID-19 propagation to social restrictions and to reduce epidemic damages through the correct tuning of the containment policy. Regarding the synthesis of this interdisciplinary approach, the extended to the susceptible–infectious–recovered (SIR) model name “SIR-PID” is suggested.
Modern cosmology successfully deals with the origin and the evolution of the Universe at large scales, but it is unable to completely answer the question about the nature of the fundamental objects ...that it is describing. As a matter of fact, about 95% of the constituents of the Universe is indeed completely unknown: it cannot be described in terms of known particles. Despite intense efforts to shed light on this “literal” darkness by dark matter and dark energy direct and indirect searches, not much progress has been made so far. In this work, we take a different perspective by reviewing and elaborating an old idea of studying the mass–radius distribution of structures in the Universe in relationship with the fundamental forces acting on them. As we will describe in detail, the distribution of the observed structures in the Universe is not completely random, but it reflects the intimate features of the involved particles and the nature of the fundamental interactions at play. The observed structures cluster in restricted regions of the mass–radius diagram linked to known particles, with the remarkable exception of very large structures that seem to be linked to an unknown particle in the sub-eV mass range. We conjecture that this new particle is a self-interacting dark matter candidate.
Cosmic-ray muon flux at Canfranc Underground Laboratory Trzaska, Wladyslaw Henryk; Slupecki, Maciej; Bandac, Iulian ...
European physical journal. C, Particles and fields,
08/2019, Letnik:
79, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Residual flux and angular distribution of high-energy cosmic muons have been measured in two underground locations at the Canfranc Underground Laboratory (LSC) using a dedicated Muon Monitor. The ...instrument consists of three layers of fast scintillation detector modules operating as 352 independent pixels. The monitor has a flux-defining area of
1
m
2
and covers all azimuth angles, and zenith angles up to
80
∘
. The measured integrated muon flux is
(
5.26
±
0.21
)
×
10
-
3
m
-
2
s
-
1
in the Hall A of the LAB2400 and
(
4.29
±
0.17
)
×
10
-
3
m
-
2
s
-
1
in LAB2500. The angular dependence is consistent with the known profile and rock density of the surrounding mountains. In particular, there is a clear maximum in the flux coming from the direction of the Rioseta valley.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Deep Underground Laboratories are multidisciplinary infrastructures to carry out research on rare events, such as neutrino interactions, proton decay, and dark matter, on geophysics, general ...relativity, and biology. There are 12 such infrastructures deployed in the north hemisphere. Three new Laboratories are underway, two in the south hemisphere. In the paper some characteristics of the Underground Laboratories are discussed. Synergy between Laboratories is reviewed.
Solar neutrinos Ianni, Aldo
Progress in particle and nuclear physics,
20/May , Letnik:
94
Journal Article
Recenzirano
In this paper we describe solar neutrino detectors and solar neutrino observations. Seven detectors have searched for solar neutrinos since 1967. In 2007 Borexino, the last one put into operation, ...started data taking. At present, only two detectors, namely Super-Kamiokande and Borexino, are taking data. In a timescale of one year SNO+ will be operational at SNOlab, replacing the SNO detector. Fundamental accomplishments have been obtained through the study of solar neutrinos. Solar neutrino data have contributed in the understanding of neutrino mixing and the MSW mechanism. Between 1991 and 1997 data from the gallium experiments made stronger the idea of new physics for neutrinos, which was initially suggested by the chlorine experiment data. In 2001 SNO and Super-Kamiokande have shown evidence of solar neutrino flavor conversion in the matter of the Sun. In 2002 SNO made this evidence more robust with the observation of neutral current interactions. The recent measurement in real-time of pp solar neutrinos from Borexino in 2014 together with previous observations provides a fundamental test of the energy source in the Sun at the level of 8%, as it is calculated in the present work. In 2005 a significant discrepancy between helioseismology and the solar models was recognized. This discrepancy replaces the previous solar neutrino problem, solved in the framework of neutrino mixing and MSW mechanism, with the solar abundance problem. Future solar neutrino measurements of CNO neutrinos could shed light on this disagreement. We review the accomplishments obtained on solar neutrino observations, discuss implications and future perspectives.
In this paper, we analyse the COVID-19 outbreak data with simple modifications of the SIR compartmental model, in order to understand the time evolution of the cases in Italy and Germany, during the ...first half of 2020. Even if the complexity of the pandemic cannot be easily described, we show that our models are suitable for understanding the data during the application of the social distancing and the lockdown. We compare and contrast different modifications of the SIR model showing the strengths and the weaknesses of each approach. Finally, we discuss the reliability of the model predictions for estimating the near- and far-future evolution of the outbreak.
The fundamental solar energy paradigm establishes that the energy in the Sun is due to a series of nuclear reactions which turn hydrogen into helium. In particular, for the Sun the fundamental ...reaction corresponds to p + p → d + e+ + υe + 0.42 MeV. This is a very slow process which drives the evolution of the Sun over a timescale of 109 years. Electron neutrinos produced in the core interact only weakly and travel almost undisturbed from the core to the surface. They are a unique probe to explore the interior of stars. Observations of solar neutrinos are discussed in the paper. The solar energy paradigm proposed in 1938 by H. Bethe has been measured in realtime by Borexino at 10% level in 2014. This observation allows to probe the solar stability over a 105 years timescale. At present, solar neutrinos offer the opportunity to understand the new Solar Abundance Problem, that is our lack of knowledge of the chemical composition of the Sun. Therefore, improving solar neutrino measurements is of great interest for astrophysics. At the same time, a better determination of some astrophysical factors will reduce uncertainties on predictions to better identify a possible inadequate assumption in the solar model.
Scientific community and institutions (e. g., ICRP) consider that the Linear No-Threshold (LNT) model, which extrapolates stochastic risk at low dose/low dose rate from the risk at moderate/high ...doses, provides a prudent basis for practical purposes of radiological protection. However, biological low dose/dose rate responses that challenge the LNT model have been highlighted and important dowels came from radiobiology studies conducted in Deep Underground Laboratories (DULs). These extreme ultra-low radiation environments are ideal locations to conduct below-background radiobiology experiments, interesting from basic and applied science. The INFN Gran Sasso National Laboratory (LNGS) (Italy) is the site where most of the underground radiobiological data has been collected so far and where the first
underground experiment was carried out using
as model organism. Presently, many DULs around the world have implemented dedicated programs, meetings and proposals. The general message coming from studies conducted in DULs using protozoan, bacteria, mammalian cells and organisms (flies, worms, fishes) is that environmental radiation may trigger biological mechanisms that can increase the capability to cope against stress. However, several issues are still open, among them: the role of the quality of the radiation spectrum in modulating the biological response, the dependence on the biological endpoint and on the model system considered, the overall effect at organism level (detrimental or beneficial). At LNGS, we recently launched the RENOIR experiment aimed at improving knowledge on the environmental radiation spectrum and to investigate the specific role of the gamma component on the biological response of
.
The study of very low energy neutrinos requires a suppression of the natural radioactivity up to ultra-traces level. This is what the Borexino experiment succeeded to achieve with the development of ...technologies for liquid purification and non-standard approaches in constructing and assembling the detector, allowing a threshold down to 50 keV. Thanks to these measures, the entire solar neutrino spectrum has been detected, neglecting the hep neutrinos which account for less than 10−5 of the total flux, together with a small, but clean and robust geoneutrino signal; they represent new achievements in the physics of the Sun, the stars and neutrinos, and they open new horizons in the study of the Earth’s interior too. This report describes the technology employed to achieve these goals and the results obtained throughout more than 10 years of data collection. Among the results, actual breakthroughs can be counted: the identification of the nuclear reactions which produce 99% of solar energy and consequently solar luminosity, combined with the demonstration of the solar stability on a 105 years scale; the confirmation of the Standard Solar Model predictions through the measured neutrino fluxes, leading the way for a significant indication in favor of the high metallicity composition of the Sun; the independent demonstration of the validity of the MSW neutrino oscillation solution, through the determination in a single experiment of the distinctive transition of the electron neutrino survival probability from the matter to the vacuum regime; and finally the achievement of the first experimental evidence of the CNO cycle, which dominates in the stars. To this date BOREXINO is a unique experiment with its unprecedented radiopurity level, achieved by means of innovative techniques, which have now become a standard reference for the whole physics field of rare events search.
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