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Bandac I.,Laboratorio Subterraneo Of Canfranc | Borjabad S.,Laboratorio Subterraneo Of Canfranc | Ianni A.,Laboratorio Subterraneo Of Canfranc | Nunez-Lagos R.,University of Zaragoza | And 3 more authors.
Applied Radiation and Isotopes | Year: 2017

To support the construction of experiments at the Laboratorio Subterráneo de Canfranc (LSC) in Spain, an Ultra-Low Background Service (ULBS) and a Copper Electroforming Service (CES) were created. The measurement technique employed at the ULBS is gamma spectroscopy with high purity germanium (HPGe) detectors. A new anti-radon system is being implemented. The main goal of CES is to obtain high-purity copper pieces. A new electroforming set-up inside LSC underground clean room is planned. Radon and environmental measurements at the LSC are presented. The ULBS and CES are reviewed. © 2017 Elsevier Ltd.


Vinyoles N.,Institute Of Ciencies Of Lespai Csic Ieec | Serenelli A.M.,Institute Of Ciencies Of Lespai Csic Ieec | Villante F.L.,University of L'Aquila | Villante F.L.,National Institute of Nuclear Physics, Italy | And 9 more authors.
Astrophysical Journal | Year: 2017

We compute a new generation of standard solar models (SSMs) that includes recent updates on some important nuclear reaction rates and a more consistent treatment of the equation of state. Models also include a novel and flexible treatment of opacity uncertainties based on opacity kernels, required in light of recent theoretical and experimental works on radiative opacity. Two large sets of SSMs, each based on a different canonical set of solar abundances with high and low metallicity (Z), are computed to determine model uncertainties and correlations among different observables. We present detailed comparisons of high- and low-Z models against different ensembles of solar observables, including solar neutrinos, surface helium abundance, depth of the convective envelope, and sound speed profile. A global comparison, including all observables, yields a p-value of 2.7σ for the high-Z model and 4.7σ for the low-Z one. When the sound speed differences in the narrow region of 0.65 < r R&M < 0.70 are excluded from the analysis, results are 0.9σ and 3.0σ for high- and low-Z models respectively. These results show that high-Z models agree well with solar data but have a systematic problem right below the bottom of the convective envelope linked to steepness of molecular weight and temperature gradients, and that low-Z models lead to a much more general disagreement with solar data. We also show that, while simple parametrizations of opacity uncertainties can strongly alleviate the solar abundance problem, they are insufficient to substantially improve the agreement of SSMs with helioseismic data beyond that obtained for high-Z models due to the intrinsic correlations of theoretical predictions. © 2017. The American Astronomical Society. All rights reserved..


Bellomo N.,University of Barcelona | Bellini E.,University of Barcelona | Bellini E.,University of Oxford | Hu B.,University of Barcelona | And 7 more authors.
Journal of Cosmology and Astroparticle Physics | Year: 2017

Cosmological observables show a dependence with the neutrino mass, which is partially degenerate with parameters of extended models of gravity. We study and explore this degeneracy in Horndeski generalized scalar-tensor theories of gravity. Using forecasted cosmic microwave background and galaxy power spectrum datasets, we find that a single parameter in the linear regime of the effective theory dominates the correlation with the total neutrino mass. For any given mass, a particular value of this parameter approximately cancels the power suppression due to the neutrino mass at a given redshift. The extent of the cancellation of this degeneracy depends on the cosmological large-scale structure data used at different redshifts. We constrain the parameters and functions of the effective gravity theory and determine the influence of gravity on the determination of the neutrino mass from present and future surveys. © 2017 IOP Publishing Ltd and Sissa Medialab srl .


Cerdeno D.G.,Autonomous University of Madrid | Marcos C.,Autonomous University of Madrid | Peiro M.,Autonomous University of Madrid | Fornasa M.,University of Nottingham | And 15 more authors.
International Journal of Modern Physics A | Year: 2014

In the last decade direct detection Dark Matter (DM) experiments have increased enormously their sensitivity and ton-scale setups have been proposed, especially using germanium and xenon targets with double readout and background discrimination capabilities. In light of this situation, we study the prospects for determining the parameters of Weakly Interacting Massive Particle (WIMP) DM (mass, spin-dependent (SD) and spin-independent (SI) cross-section off nucleons) by combining the results of such experiments in the case of a hypothetical detection. In general, the degeneracy between the SD and SI components of the scattering cross-section can only be removed using targets with different sensitivities to these components. Scintillating bolometers, with particle discrimination capability, very good energy resolution and threshold and a wide choice of target materials, are an excellent tool for a multitarget complementary DM search. We investigate how the simultaneous use of scintillating targets with different SD-SI sensitivities and/or light isotopes (as the case of CaF2 and NaI) significantly improves the determination of the WIMP parameters. In order to make the analysis more realistic we include the effect of uncertainties in the halo model and in the spin-dependent nuclear structure functions, as well as the effect of a thermal quenching different from 1. © 2014 World Scientific Publishing Company.


Jordan D.,University of Valencia | Tain J.L.,University of Valencia | Algora A.,University of Valencia | Agramunt J.,University of Valencia | And 11 more authors.
Astroparticle Physics | Year: 2013

The energy distribution of the neutron background was measured for the first time at Hall A of the Canfranc Underground Laboratory. For this purpose we used a novel approach based on the combination of the information obtained with six large high-pressure 3He proportional counters embedded in individual polyethylene blocks of different size. In this way not only the integral value but also the flux distribution as a function of neutron energy was determined in the range from 1 eV to 10 MeV. This information is of importance because different underground experiments show different neutron background energy dependence. The high sensitivity of the setup allowed to measure a neutron flux level which is about four orders of magnitude smaller that the neutron background at sea level. The integral value obtained is ΦHall A=(3.44±0.35)×10-6 cm-2 s-1. © 2012 Elsevier B.V. All rights reserved.


Cebrian S.,University of Zaragoza | Cebrian S.,Laboratorio Subterraneo Of Canfranc
AIP Conference Proceedings | Year: 2013

The production of radioactive isotopes in materials due to exposure to cosmic rays can become an hazard for experiments demanding ultra-low background conditions. Generation of long-lived products by cosmic nucleons at sea level has been studied for detector materials like germanium and tellurium and for other materials commonly used like copper; the main results will be summarized, considering both measurements and calculations. The isotope production cross sections and the cosmic ray spectrum are the two main ingredients when calculating this cosmogenic activation; the different alternatives for implementing them will be discussed. But cosmogenic activation can take place also deep underground due to cosmic muons, being relevant in this case the short-lived products. Studies carried out to evaluate the underground activation mainly for liquid scintillator materials will be commented too. © 2013 AIP Publishing LLC.


Cebrian S.,University of Zaragoza | Cebrian S.,Laboratorio Subterraneo Of Canfranc | Cuesta C.,University of Zaragoza | Cuesta C.,Laboratorio Subterraneo Of Canfranc | And 26 more authors.
Astroparticle Physics | Year: 2012

NaI (Tl) is a well known high light yield scintillator. Very large crystals can be grown to be used in a wide range of applications. In particular, such large crystals are very good-performing detectors in the search for dark matter, where they have been used for a long time and reported first evidence of the presence of an annual modulation in the detection rate, compatible with that expected for a dark matter signal. In the frame of the ANAIS (Annual modulation with NaI Scintillators) dark matter search project, a large and long effort has been carried out in order to characterize the background of sodium iodide crystals. In this paper we present in detail our background model for a 9.6 kg NaI (Tl) detector taking data at the Canfranc Underground Laboratory (LSC): most of the contaminations contributing to the background have been precisely identified and quantified by different complementary techniques such as HPGe spectrometry, discrimination of alpha particles vs. beta/gamma background by Pulse Shape Analysis (PSA) and coincidence techniques; then, Monte Carlo (MC) simulations using Geant4 package have been carried out for the different contributions. Only a few assumptions are required in order to explain most of the measured background at high energy, supporting the goodness of the proposed model for the present ANAIS prototype whose background is dominated by 40K bulk contamination. At low energy, some non-explained background components are still present and additional work is required to improve background understanding, but some plausible background sources contributing in this range have been studied in this work. Prospects of achievable backgrounds, at low and high energy, for the ANAIS-upgraded detectors, relying on the proposed background model conveniently scaled, are also presented. © 2012 Elsevier B.V. All rights reserved.


Bettini A.,Laboratorio Subterraneo Of Canfranc | Bettini A.,University of Padua | Bettini A.,National Institute of Nuclear Physics, Italy
Physics of the Dark Universe | Year: 2014

Deep underground laboratories provide the low radioactive background environment necessary to explore the highest energy scales that cannot be reached with accelerators, by searching for extremely rare phenomena. In addition, these laboratories provide unique opportunities to sectors of other fields: geodynamics, rock mechanics, hydrology and the study of life under extreme conditions. Underground laboratories of different size and depth exist in all the regions. This article is focussed on future perspectives, reviewing the newer facilities, those still under project and the space becoming available at the older laboratories. We shall not discuss the existing or proposed facilities dedicated to detectors of long base line experiment with reactor or accelerator beams. © 2014.


Bettini A.,Laboratorio Subterraneo Of Canfranc | Bettini A.,University of Padua
European Physical Journal Plus | Year: 2012

The Canfranc Underground Laboratory, presently the second largest in Europe, is located under the Mount Tobazo in the central Spanish Pyrenees, in the province of Huesca in Aragón. After recalling a few historical elements, I shall describe the LSC infrastructures and services both underground and the support ones on the surface. I shall then report the characterisation measurements done so far. A summary of the approved experiments and projects for the future will complete the article. © 2012, Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg.


Bettini A.,University of Padua | Bettini A.,Laboratorio Subterraneo Of Canfranc
European Physical Journal Plus | Year: 2012

This paper is an introduction to a series of coordinated articles of an EPJ Plus Focus Point on underground physics laboratories, written by the directors of the larger ones and by the coordinators of the principal new projects. The paper is largely based on the text of my lecture Perspectives of underground physics, given at the Enrico Fermi Varenna International School, Course CLXXXII (2011), Neutrino physics and astrophysics, reproduced here by permission of the Italian Physical Society. Underground laboratories provide the low radioactive background environment necessary to explore the highest energy scales that cannot be reached with accelerators, by searching for extremely rare phenomena. Experiments range from the direct search of the dark-matter particles that constitute the largest fraction of matter in the Universe, to the exploration of the properties of the neutrinos, the most elusive of the known particles and which might be particle and antiparticle at the same time, to the investigation on why our universe contains only matter and almost no antimatter, and much more. © 2012, Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg.

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