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1.
Phys Rev Lett ; 132(6): 061001, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38394588

RESUMO

We show that ATLAS, a collider detector, can measure the flux of high-energy supernova neutrinos, which can be produced from days to months after the explosion. Using Monte Carlo simulations for predicted fluxes, we find at most O(0.1-1) starting events and O(10-100) throughgoing events from a supernova 10 kpc away. Possible Galactic supernovae from Betelgeuse and Eta Carinae are further analyzed as demonstrative examples. We argue that, even with limited statistics, ATLAS has the ability to discriminate among flavors and between neutrinos and antineutrinos, making it a unique neutrino observatory so far unmatched in this capability.

2.
Phys Rev Lett ; 123(26): 261801, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31951430

RESUMO

Heavy neutrinos with additional interactions have recently been proposed as an explanation to the MiniBooNE excess. These scenarios often rely on marginally boosted particles to explain the excess angular spectrum, thus predicting large rates at higher-energy neutrino-electron scattering experiments. We place new constraints on this class of models based on neutrino-electron scattering sideband measurements performed at MINERνA and CHARM-II. A simultaneous explanation of the angular and energy distributions of the MiniBooNE excess in terms of heavy neutrinos with light mediators is severely constrained by our analysis. In general, high-energy neutrino-electron scattering experiments provide strong constraints on explanations of the MiniBooNE observation involving light mediators.

3.
Phys Rev Lett ; 119(20): 201801, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29219351

RESUMO

We show that the high-energy cosmic neutrinos seen by the IceCube Neutrino Observatory can be used to probe interactions between neutrinos and the dark sector that cannot be reached by current cosmological methods. The origin of the observed neutrinos is still unknown, and their arrival directions are compatible with an isotropic distribution. This observation, together with dedicated studies of Galactic plane correlations, suggests a predominantly extragalactic origin. Interactions between this isotropic extragalactic flux and the dense dark matter (DM) bulge of the Milky Way would thus lead to an observable imprint on the distribution, which would be seen by IceCube as (i) slightly suppressed fluxes at energies below a PeV and (ii) a deficit of events in the direction of the Galactic center. We perform an extended unbinned likelihood analysis using the four-year high-energy starting event data set to constrain the strength of DM-neutrino interactions for two model classes. We find that, in spite of low statistics, IceCube can probe regions of the parameter space inaccessible to current cosmological methods.

4.
Phys Rev Lett ; 115(16): 161303, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26550862

RESUMO

Astrophysical neutrinos are powerful tools for investigating the fundamental properties of particle physics through their flavor content. In this Letter, we perform the first general new physics study on ultrahigh energy neutrino flavor content by introducing effective operators. We find that, at the current limits on these operators, new physics terms cause maximal effects on the flavor content; however, the flavor content on the Earth is confined to a region related to the assumed initial flavor content. Furthermore, we conclude that a precise measure of the flavor content on the Earth will provide orders of magnitude improvement on new physics bounds. Finally, we discuss the current best fits of flavor content of the IceCube data and their interplay with new physics scenarios.

5.
Acad Emerg Med ; 9(6): 646-9, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12045084

RESUMO

UNLABELLED: Recent studies suggest that women with acute urethral syndrome or abdominal pain, presenting to emergency departments (EDs), have a high prevalence of Chlamydia trachomatis. OBJECTIVES: To estimate the prevalence of C. trachomatis in women presenting to an ED and to see whether those with dysuria or abdominal pain have a higher prevalence of C. trachomatis. METHODS: The authors conducted a prospective cross-sectional study of C. trachomatis in the urine of women aged 18 to 50 years who had a urinalysis performed at a university/county ED from February through May 1998. Urine specimens were labeled for the presence of symptoms and analyzed for C. trachomatis by ligase chain reaction (LCR). Polymerase chain reaction (PCR) testing of cervical swabs for C. trachomatis was done for usual clinical indications. Difference in proportions of positive LCR tests among patients was tested with Fisher's exact test. Agreement between PCR and LCR was measured using Cohen's kappa statistic. RESULTS: Of 397 women whose urine was tested, 280 had symptoms of dysuria, abdominal pain, or both, and 117 had no symptoms. The overall prevalence of C. trachomatis by LCR was 3.8% (95% CI = 2.1% to 6.2%); and the combined PCR-LCR prevalence was 4.3% (95% CI = 2.5% to 6.8%). The presence of symptoms was not associated with a positive LCR test for C. trachomatis (p = 0.26, power = 0.8, alpha = 0.05, difference 3% vs. 12%). In the 172 patients who had both a PCR cervical swab and urine LCR, agreement was excellent (kappa = 0.67, 95% CI = 0.45 to 0.90). CONCLUSIONS: This ED had a surprisingly low prevalence of C. trachomatis. Women with symptoms were not more likely to test positive than those without.


Assuntos
Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Chlamydia trachomatis/isolamento & purificação , Serviço Hospitalar de Emergência/estatística & dados numéricos , Programas de Rastreamento/métodos , Dor Abdominal/microbiologia , Adolescente , Adulto , Colo do Útero/microbiologia , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/urina , Estudos Transversais , Feminino , Humanos , Reação em Cadeia da Ligase , Pessoa de Meia-Idade , New Mexico/epidemiologia , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Urina/microbiologia
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