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1.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38277596

ABSTRACT

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

2.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36827568

ABSTRACT

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

3.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Article in English | MEDLINE | ID: mdl-33929235

ABSTRACT

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

4.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Article in English | MEDLINE | ID: mdl-33016715

ABSTRACT

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

5.
Phys Rev Lett ; 117(19): 192001, 2016 Nov 04.
Article in English | MEDLINE | ID: mdl-27858429

ABSTRACT

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.

6.
Phys Rev Lett ; 116(24): 241101, 2016 Jun 17.
Article in English | MEDLINE | ID: mdl-27367377

ABSTRACT

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.

7.
Eur Phys J C Part Fields ; 75(6): 269, 2015.
Article in English | MEDLINE | ID: mdl-26120280

ABSTRACT

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

8.
Actas esp. psiquiatr ; 36(6): 323-330, nov.-dic. 2008. tab
Article in Es | IBECS | ID: ibc-69163

ABSTRACT

Introducción. El objetivo del estudio fue adaptar y validaren castellano la Insight Scale (IS) (Birch wood et al., 1994), escala auto aplicada que evalúa el insight multidimensionalmente. Método. Estudio observacional de una muestra clínica de pacientes con psicosis. Se realizó una traducción y una retrotraducción. Se calculó la factibilidad, la validez de criterio concurrente con el ítem 12 de la PANSS, la validez de constructo convergente con la DAI y divergente con la BPRS, la validez de constructo discriminante entre las puntuaciones de la IS de pacientes ingresados voluntaria e involuntariamente, la validez de contenido, la fiabilidad test retest y la consistencia interna. Resultados. La muestra constó de 61 pacientes. El coeficiente de correlación intraclase (CCI) entre el ítem 12 de la PANSS y la IS fue de 0,49. La correlación entre la IS y la DAI y la IS y la BPRS fue de 0,414 (p=0,01) y –0,14, respectivamente. Las puntuaciones medias de la IS de los pacientes ingresados voluntariamente (8,37) e involuntariamente (6,21) fueron significativamente diferentes (U de Mann-Whitney: 244,5; p=0,005). Tres factores explicaron el 68,32% de la varianza de las puntuaciones de la IS. El CCI test-retest fue 0,765. El α de Cronbach fue 0,717. Conclusiones. La versión española de la IS es un instrumento de evaluación del insight breve, sencillo, autoaplicado y multidimensional, con adecuadas propiedades psicométricas (AU)


Introduction. The aim of our study was to validate the Spanish version of the Insight Scale (IS) (Birchwood et al., 1994), a multidimensional self-report insight scale. Method. Observational study in a sample of patients with psychosis. A translation-back translation of the original scale was elaborated. Feasibility was calculated. Concurrent criteria validity with item 12 of PANSS, construct convergent and divergent validity with DAI and BPRS were calculated. IS scores between voluntary and involuntary inpatients were used for discriminant validity. Factor analysis, temporal reliability and internal consistency were also examinated. Results. The sample consisted of 61 patients. Interclass Correlation Coeficient (ICC) between item 12 of PANSS and IS was 0.49. Correlation between IS and DAI, and IS and BPRS was 0.414 (p=0.01) and –0.14 respectively. Difference between mean IS scores of voluntary (8.37) and involuntary inpatients (6.21) was signific (U test Mann-Whitney: 244.5; p=0.005). Three factors were extracted that accounted for 68.32% of variance. Cronbachα was 0,717. Conclusions. The Spanish version of IS is a quick, simple, self-report and multidimensional instrument of insight with satisfactory psychometric properties (AU)


Subject(s)
Humans , Male , Female , Adult , Psychometrics/methods , Affective Disorders, Psychotic/epidemiology , Affective Disorders, Psychotic/psychology , Signs and Symptoms , Awareness/physiology , Surveys and Questionnaires , Psychopathology/methods , Factor Analysis, Statistical , Psychometrics/trends , Spain/epidemiology , Psychotic Disorders/psychology , Diagnostic and Statistical Manual of Mental Disorders , Psychopathology/statistics & numerical data , Psychopathology/trends , Feasibility Studies , /instrumentation
9.
Actas Esp Psiquiatr ; 36(6): 323-30, 2008.
Article in English | MEDLINE | ID: mdl-18833495

ABSTRACT

INTRODUCTION: The aim of our study was to validate the Spanish version of the Insight Scale (IS) (Birchwood et al., 1994), a multidimensional self-report insight scale. METHOD: Observational study in a sample of patients with psychosis. A translation-backtranslation of the original scale was elaborated. Feasibility was calculated. Concurrent criteria validity with item 12 of PANSS, construct convergent and divergent validity with DAI and BPRS were calculated. IS scores between voluntary and involuntary inpatients were used for discriminant validity. Factor analysis, temporal reliability and internal consistency were also examinated. RESULTS: The sample consisted of 61 patients. Interclass Correlation Coeficient (ICC) between item 12 of PANSS and IS was 0.49. Correlation between IS and DAI, and IS and BPRS was 0.414 (p=0.01) and -0.14 respectively. Difference between mean IS scores of voluntary (8.37) and involuntary inpatients (6.21) was signific (U test Mann-Whitney: 244.5; p=0.005). Three factors were extracted that accounted for 68.32% of variance. Cronbach alpha was 0,717. CONCLUSIONS: The Spanish version of IS is a quick, simple, self-report and multidimensional instrument of insight with satisfactory psychometric properties.


Subject(s)
Attitude , Language , Psychometrics/standards , Surveys and Questionnaires , Feasibility Studies , Humans , Reproducibility of Results , Spain
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