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Presentation from Neutrino Platform Week 2019: Hot Topics in Neutrino Physics, CERN, 7-11 October 2019

The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is a NASA Astrophysics probe-class mission designed to observe ultra-high energy cosmic rays (UHECRs) and cosmic neutrinos from space. Astro2020 APC white paper: Medium-class Space Particle Astrophysics Project., Comment: Astro2020 APC white paper: Medium-class Space Particle Astrophysics Project

International audience; Neutrino astronomy has seen tremendous progress over recent years with the discovery of a diffuse flux of astrophysical neutrinos in the TeV–PeV energy range and the first compelling evidence of neutrino emission from gamma-ray blazars. Neutrinos are unique cosmic messengers that allow to discover and characterize the most energetic non-thermal sources in the Universe.We consider the possibility of observing transient neutrino sources in the GeV–TeV energy range, where neutrino telescopes are limited by atmospheric backgrounds. The production of these intermediate-energy neutrinos likely proceeds via proton interactions with ambient matter in the source and with the surrounding background gas. We study the production of GeV–TeV neutrinos based on GEANT4 simulations. We also investigate the impact of high-density environments on the development of particle cascades and secondary neutrino spectra.

The astrophysical neutrinos discovered by IceCube have the highest detected neutrino energies --- from TeV to PeV --- and likely travel the longest distances --- up to a few Gpc, the size of the observable Universe. These features make them naturally attractive probes of fundamental particle-physics properties, possibly tiny in size, at energy scales unreachable by any other means. The decades before the IceCube discovery saw many proposals of particle-physics studies in this direction. Today, those proposals have become a reality, in spite of astrophysical unknowns. We will showcase examples of doing fundamental neutrino physics at these scales, including some of the most stringent tests of physics beyond the Standard Model. In the future, larger neutrino energies --- up to tens of EeV --- could be observed with larger detectors and further our reach.

The flavor composition of high-energy astrophysical neutrinos is a rich observable. However, present analyses cannot effectively distinguish particle showers induced by $\nu_e$ versus $\nu_\tau$. We show that this can be accomplished by measuring the intensities of the delayed, collective light emission from muon decays and neutron captures, which are, on average, greater for $\nu_\tau$ than for $\nu_e$. This new technique would significantly improve tests of the nature of astrophysical sources and of neutrino properties. We discuss the promising prospects for implementing it in IceCube and other detectors., Comment: 13 pages, 9 figures. Matches published version

Astrophysical searches for new long-range interactions complement collider searches for new short-range interactions. Conveniently, neutrino flavor oscillations are keenly sensitive to the existence of long-ranged flavored interactions between neutrinos and electrons, motivated by lepton-number symmetries of the Standard Model. For the first time, we probe them using TeV-PeV astrophysical neutrinos and accounting for all large electron repositories in the local and distant Universe. The high energies and colossal number of electrons grant us unprecedented sensitivity to the new interaction, even if it is extraordinarily feeble. Based on IceCube results for the flavor composition of astrophysical neutrinos, we set the ultimate bounds on long-range neutrino flavored interactions., Comment: 5 pages main text, 10 figures, technical appendices. Matches published version. Selected as PRL Editors' Suggestion. APS Physics Synopsis: https://physics.aps.org/synopsis-for/10.1103/PhysRevLett.122.061103

We review open questions and prospects for progress in ultrahigh-energy cosmic ray (UHECR) research, based on a series of discussions that took place during the `The High-Energy Universe: Gamma-Ray, Neutrino, and Cosmic-ray Astronomy' MIAPP workshop in 2018. Specifically, we overview open questions on the origin of the bulk of UHECRs, the UHECR mass composition, the origin of the end of the cosmic-ray spectrum, the transition from Galactic to extragalactic cosmic rays, the effect of magnetic fields on the trajectories of UHECRs, anisotropy expectations for specific astrophysical scenarios, hadronic interactions, and prospects for discovering neutral particles as well as new physics at ultrahigh energies. We also briefly present upcoming and proposed UHECR experiments and discuss their projected science reach., 47 pages, 17 figures, Review to appear in "Frontiers in Astronomy and Space Science" special issue, "Multi-Messenger Astrophysics: New Windows to the Universe"

The sources and production mechanisms of high-energy astrophysical neutrinos are largely unknown. A promising opportunity for progress lies in the study of neutrino flavor composition, i.e., the proportion of each flavor in the flux of neutrinos, which reflects the physical conditions at the sources. To seize it, we introduce a Bayesian method that infers the flavor composition at the neutrino sources based on the flavor composition measured at Earth. We find that present data from the IceCube neutrino telescope favor neutrino production via the decay of high-energy pions and rule out production via the decay of neutrons. In the future, improved measurements of flavor composition and mixing parameters may single out the production mechanism with high significance., Comment: 5 pages, 3 figures, technical appendices. Matches published version

In neutrino oscillations, a neutrino created with one flavor can be later detected with a different flavor, with some probability. In general, the probability is computed exactly by diagonalizing the Hamiltonian operator that describes the physical system and that drives the oscillations. Here we use an alternative method developed by Ohlsson & Snellman to compute exact oscillation probabilities, that bypasses diagonalization, and that produces expressions for the probabilities that are straightforward to implement. The method employs expansions of quantum operators in terms of SU(2) and SU(3) matrices. We implement the method in the code NuOscProbExact, which we make publicly available. It can be applied to any closed system of two or three neutrino flavors described by an arbitrary time-independent Hamiltonian. This includes, but is not limited to, oscillations in vacuum, in matter of constant density, with non-standard matter interactions, and in a Lorentz-violating background., 8 pages, 1 figure, code examples, improved discussion, technical appendices. NuOscProbExact code: http://github.com/mbustama/NuOscProbExact

The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is designed to observe cosmic neutrinos (CNs) above 20 PeV and ultra-high energy cosmic rays (UHECRs) above 20 EeV over the full sky. The POEMMA mission calls for two identical satellites flying in loose formation, each comprised of a 4-meter wide field-of-view (45 degrees) Schmidt photometer. The hybrid focal surface includes a fast (1 ${\mu}$s) ultraviolet camera for fluorescence observations and an ultrafast (10 ns) optical camera for Cherenkov observations. POEMMA will provide new multi-messenger windows onto the most energetic events in the universe, enabling the study of new astrophysics and particle physics at these otherwise inaccessible energies., Comment: 8 pages, 6 figures, presented in 36th International Cosmic Ray Conference (Madison). arXiv admin note: substantial text overlap with arXiv:1907.06217

We prove that the space of complete, finite volume, pinched negatively curved Riemannian metrics on a smooth high-dimensional manifold is either empty or it is highly non-connected, provided their behavior at infinity is similar., Comment: 13 pages, 3 figures. Definition in Section 1 added. Revised arguments in Section 2

Microbial communities of anaerobic digestion have been intensively investigated in the past decades. Majority of these studies focused on correlating microbial diversity with biogas production. The relationship between microbial communities and compositional changes of the solid digestate (AD fiber) has not been comprehensively studied to date. Therefore, the objective of this study was to understand the responses of microbial communities to different operational conditions of anaerobic co-digestion and their influences on biogas production and solid digestate quality. Two temperatures and three manure-to-food waste ratios were investigated by a completely randomized design. Molecular analyses demonstrate that both temperature and manure-to-food waste ratio greatly influenced the bacterial communities, while archaeal communities were mainly influenced by temperature. The digestion performance showed that biogas productivity increased with the increase of supplemental food wastes, and there were no significant differences on carbohydrate contents among different digestions. The statistical analyses conclude that microbes changed their community configuration under different conditions to enhance digestion performance for biogas and homogenized solid digestate production. U.S. Department of State West Hemisphere Affairs/[S-LMAQM-11-GR-075]//Estados Unidos UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Estación Experimental Agrícola Fabio Baudrit Moreno (EEAFBM)

Rhizopus chinensis (CCTCC 2010021) is a filamentous fungus that demonstrates a good capability to produce mycelium-bound lipase (mb-RCL) for ester synthesis in non-aqueous solutions. It has been reported that the mycelial aggregation of the fungal growth promotes mb-RCL production compared to free cell growth. This study modified a stirred tank reactor (STR) to accommodate a perforated draft tube so that aggregated growth of the fungal mycelia in the reactor was achieved. The aggregated growth on the draft tube not only improves mb-RCL accumulation but also changes the broth’s rheological properties. Computational fluid dynamic (CFD) modeling and flow pattern verification conclude that the preferred fermentation condition was agitation at 600 rpm and aeration at 1 vvm (4 L/min). Under this condition, the aggregated R. chinensis in the modified STR can fully utilize olive oil to accumulate 19 g/L fungal biomass. The mb-RCL activity reached 325 U/g, which corresponds to a total enzyme activity of 6185 U/L fermentation broth. It was 6.5 times greater than the total enzyme activity in free cell fermentation. These results indicate that controlling the flow pattern of the broth by changing the agitation and aeration in the modified fermentor are able to improve mixing and mass transfer and lead to a better fermentation performance.

Perennial grasses are the promising source of bioenergy in South America which could provide several environmental benefits such as reduction in the greenhouse gasses emissions and reduction of nutrients and soil losses. Our objective was to determine the impact of N and P fertilization on biomass yield, N use efficiency (NUE), apparent N recovery (ANR), and nutrient removal (NR) on three perennial grasses: elephantgrass (Pennisetum purpureum Schum.), giant reed (Arundo donax L.), and switchgrass (Panicum virgatum L.). Four fertility treatments were evaluated in a 8-year field study in northwestern Uruguay: 1. control (No fertilizer), 2.100 kg N ha−1 year−1, 3.100 kg P2O5 ha−1 year−1, and 4.100 kg N + 100 kg P2O5 ha−1 year−1. Across years, elephantgrass had the highest biomass yield followed by giant reed and switchgrass (18.9, 16.3, and 14.1 Mg ha−1, respectively). Biomass yield increased 46% when N fertilizer was added, compared to the control. A low response was detected for P fertilization on all grasses, probably for initial P soil content (≥9 g kg−1). Elephantgrass had the highest NUE (70 kg kg−1 N), however, it had the highest total NR on these eight years (899, 226, and 2800 kg ha−1 for N–P–K, respectively) among the grasses, indicating a potential for increased fertilization input over time. Switchgrass had the lowest average ANR (19%) and NR (334, 45, and 166 kg ha−1, respectively). Therefore, even though switchgrass presented the lowest biomass yield, it is an excellent option as low-input bioenergies grass for temperate regions.

The flavor composition of astrophysical neutrinos observed at neutrino telescopes is related to the initial composition at their sources via oscillation-averaged flavor transitions. If the time evolution of the neutrino flavor states is unitary, the probability of neutrinos changing flavor is solely determined by the unitary mixing matrix that relates the neutrino flavor and propagation eigenstates. In this paper we derive general bounds on the flavor composition of TeV-PeV astrophysical neutrinos based on unitarity constraints. These bounds are useful for studying the flavor composition of high-energy neutrinos, where energy-dependent nonstandard flavor mixing can dominate over the standard mixing observed in accelerator, reactor, and atmospheric neutrino oscillations., revised manuscript published in Phys. Rev. D 98, 123023 (2018)

OBJECTIVE Multi-channel electrical recordings of physiologically generated signals are common to a wide range of biomedical fields. The aim of this work was to develop, validate, and demonstrate the practical utility of a high-quality, low-cost 32/64-channel bioamplifier system with real-time wireless data streaming capability. APPROACH The new 'Intsy' system integrates three main off-the-shelf hardware components: (1) Intan RHD2132 bioamplifier; (2) Teensy 3.2 microcontroller; and (3) RN-42 Bluetooth 2.1 module with a custom LabView interface for real-time data streaming and visualization. Practical utility was validated by measuring serosal gastric slow waves and surface EMG on the forearm with various contraction force levels. Quantitative comparisons were made to a gold-standard commercial system (Biosemi ActiveTwo). MAIN RESULTS Intsy signal quality was quantitatively comparable to that of the ActiveTwo. Recorded slow wave signals had high SNR (24 ± 2.7 dB) and wavefront propagation was accurately mapped. EMG spike bursts were characterized by high SNR (⩾10 dB) and activation timing was readily identified. Stable data streaming rates achieved were 3.5 kS s-1 for wireless and 64 kS s-1 for USB-wired transmission. SIGNIFICANCE Intsy has the highest channel count of any existing open-source, wireless-enabled module. The flexibility, portability and low cost ($1300 for the 32-channel version, or $2500 for 64 channels) of this new hardware module reduce the entry barrier for a range of electrophysiological experiments, as are typical in the gastrointestinal (EGG), cardiac (ECG), neural (EEG), and neuromuscular (EMG) domains.

François Dubet es sociólogo e investigador de la prestigiosa École des hautes études en sciences sociales (EHESS). Conocido por sus investigaciones sobre educación, movimientos sociales y desigualdades, es uno de los herederos de la sociología de Alain Touraine. En un corto ensayo publicado en Francia en el 2014 y traducido rápidamente al castellano por Siglo XXI Editores, Dubet se interesa en dar respuesta a la pregunta: ¿Por qué preferimos la desigualdad? Este interrogante es de hecho el título del libro, en el cual Dubet desarrolla la idea de que “la crisis de las solidaridades” se explicaría en gran medida porque las sociedades eligen la desigualdad; es decir, “la intensificación de las desigualdades procede de una crisis de las solidaridades” (p. 11).

We prove that the Teichm��ller space $\mathcal{T}^{ \dim M$. Moreover, some elements of infinite order in $��_i B\mbox{Diff}(M)$ can be represented by bundles over $S^i$ with fiberwise negatively curved metrics., Referrences added;other minor changes

Background: Given the level of technological pro- gress made today is that civic and government institutions seek to replicate the success of systems like the financial sector and banking in electronic voting systems. Objective: To make an analysis for the developed systems to conduct electronic voting from the Requirements Engineering perspective. Method: We use the methodology of systematic mapping study. Initially, we collect 240 publications and finally selecting 60 works. The Non Functional Requirements selected were Security, Performance efficiency, Reliability and Operability, which were chosen from several publications suggesting that this group was critical to the successful adoption of electronic voting systems. Results: The results show that 49 % of the proposals considered Security feature the most relevant, which is consistent with the literature. The 23% of publications addressing Performance Efficiency, revealing that the main problem today is to build a model of electronic voting that is safe and can be widely implemented dedicating a reasonable amount of resources. Conclusions: A set of recommendations was generated. Given the complexity of e- vote systems, these must be addressed holistically.

Solar energy is the most abundant energy resource with the potential to become a major component of a sustainable global energy solution. However, unsteady energy flow and low energy density make it difficult to collect, convert, and store solar energy, which is why current solar power generation technologies have limited applications. This paper comprehensively studied the integration of solar thermal collection with different anaerobic digestion operations to form solar-bioreactor systems in order to realize biological storage of solar energy and solve the issues that solar energy generation encounters. The experimental comparison of manure digestion and co-digestion concluded that co-digestion had a better methane yields with a minimum difference between mesophilic and thermophilic conditions. The energy analysis of solar-bioreactor systems with both manure digestion and co-digestion at different bioreactor sizes further concluded that solar-bioreactor systems with mesophilic co-digestion was the preferred system to store solar energy into methane biogas. The optimal solar-storage efficiencies for the three systems of 10, 100, 1000 m3 were 67%, 68% and 70%, respectively. The corresponding solar-bioreactor system efficiencies were 82%, 88%, and 89%.

We reconsider the possibility that gamma-ray bursts (GRBs) are the sources of the ultra-high energy cosmic rays (UHECRs) within the internal shock model, assuming a pure proton composition of the UHECRs. For the first time, we combine the information from gamma-rays, cosmic rays, prompt neutrinos, and cosmogenic neutrinos quantitatively in a joint cosmic ray production and propagation model, and we show that the information on the cosmic energy budget can be obtained as a consequence. In addition to the neutron model, we consider alternative scenarios for the cosmic ray escape from the GRBs, i.e., that cosmic rays can leak from the sources. We find that the dip model, which describes the ankle in UHECR observations by the pair production dip, is strongly disfavored in combination with the internal shock model because a) unrealistically high baryonic loadings (energy in protons versus energy in electrons/gamma-rays) are needed for the individual GRBs and b) the prompt neutrino flux easily overshoots the corresponding neutrino bound. On the other hand, GRBs may account for the UHECRs in the ankle transition model if cosmic rays leak out from the source at the highest energies. In that case, we demonstrate that future neutrino observations can efficiently test most of the parameter space -- unless the baryonic loading is much larger than previously anticipated., 55 pages, 23 figures, 1 table. Version accepted for publication in Astroparticle Physics. Main analysis performed with TA data; for plots with HiRes data, see v1

The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) mission is being designed to establish charged-particle astronomy with ultra-high energy cosmic rays (UHECRs) and to observe cosmogenic tau neutrinos (CTNs). The study of UHECRs and CTNs from space will yield orders-of-magnitude increase in statistics of observed UHECRs at the highest energies, and the observation of the cosmogenic flux of neutrinos for a range of UHECR models. These observations should solve the long-standing puzzle of the origin of the highest energy particles ever observed, providing a new window onto the most energetic environments and events in the Universe, while studying particle interactions well beyond accelerator energies. The discovery of CTNs will help solve the puzzle of the origin of UHECRs and begin a new field of Astroparticle Physics with the study of neutrino properties at ultra-high energies., 8 pages, in the Proceedings of the 35th International Cosmic Ray Conference, ICRC217, Busan, Korea

International audience; The very low flux of ultra-high-energy cosmic-rays (UHECRs) requires detectors with a large effective area and high duty cycle to obtain a statistically relevant sample. Radio detection of extensive air showers (EAS) presents attractive aspects for future giant detectors of high energy cosmic particles, with very low cost per detection unit, easiness of deployment over large areas, and a duty cycle close to 100%. However autonomous detection of EAS -a necessary step towards the realization of this type of ambitious detectors- remains a challenge.GRANDproto35 aims at demonstrating that radio-detection of air showers can be performed with very good background rejection, high efficiency, and an almost 100% duty cycle. The 35 GRANDproto antennas will perform a full measurement of the detected wave polarization. This makes GRANDproto35 uniquely qualified for the investigation of polarization characteristics of the radio emission from EAS, which may contribute to discriminate them from background signals. In addition, an array of 24 scintillators will allow offline cross-checks of the nature of the selected radio-candidates. We detail here the principle, progress and prospects of GRANDproto35, which serves as a step towards the Giant Radio Array for Neutrino Detection (GRAND) project. GRAND will consist of an array of ∼ 10^5 radio antennas deployed over ∼ 200, 000 km^2 in mountainous sites.

We prove that certain involutions defined by Vogell and Burghelea-Fiedorowicz on the rational algebraic $K$-theory of spaces coincide. This gives a way to compute the positive and negative eigenspaces of the involution on rational homotopy groups of pseudoisotopy spaces from the involution on rational $S^{1}$-equivariant homology group of the free loop space of a simply-connected manifold. As an application, we give explicit dimensions of the open manifolds $V$ that appear in Belegradek-Farrell-Kapovitch's work for which the spaces of complete nonnegatively curved metrics on $V$ have nontrivial rational homotopy groups., 23 pages, to appear in Transactions of the AMS

La presente guía recoge más de cuarenta años de experiencia en la enseñanza de la física dentro del contexto experimental universitario, cuyos propósitos y tendencias pedagógicas han evolucionado a la par con los avances tecnológicos en la medición y la computación. Por tal razón, las metas generales del texto son aproximar al estudiante a la praxis experimental en el ámbito de la física y reproducir dentro del proceso mismo de la mediación educativa una actitud similar a la manera rigurosa y exhaustiva con la cual un investigador profesional, ya en el campo de la ciencia, ejecuta su labor de indagación y generación de conocimiento, por supuesto, en su justa proporción.

Neutrinos are key to probing the deep structure of matter and the high-energy Universe. Yet, until recently, their interactions had only been measured at laboratory energies up to about 350 GeV. An opportunity to measure their interactions at higher energies opened up with the detection of high-energy neutrinos in IceCube, partially of astrophysical origin. Scattering off matter inside the Earth affects the distribution of their arrival directions --- from this, we extract the neutrino-nucleon cross section at energies from 18 TeV to 2 PeV, in four energy bins, in spite of uncertainties in the neutrino flux. Using six years of public IceCube High-Energy Starting Events, we explicitly show for the first time that the energy dependence of the cross section above 18 TeV agrees with the predicted softer-than-linear dependence, and reaffirm the absence of new physics that would make the cross section rise sharply, up to a center-of-mass energy of ~1 TeV., Comment: 5 pages main text, 5 figures, technical appendices. Matches published version

El objetivo de este artículo fue analizar datos meteorológicos para identificar el comportamiento de variables físicas de relevancia y definir el clima de la región y el microclima de Yopal, Casanare. Se estudiaron los registros de las variables climáticas en una serie de tiempo de treinta años en la estación meteorológica del aeropuerto de Yopal, los cuales fueron suministrados por el Instituto de Estudios Ambientales y Meteorológicos (Ideam). Luego se llevó a cabo una tipificación climática basada en las clasificaciones más utilizadas por la comunidad científica, como son Thornthwaite, De Martone y Koppen, con el propósito de situar climáticamente la región de estudio. Por último, se analizaron las dos variables físicas más importantes en cuanto al comportamiento del microclima del lugar respecto al crecimiento de la vegetación, por sus procesos de evapotranspiración y uso del recurso hídrico.

This article (1) examines the social distribution of cultural practices in Australia, and (2) compares this with similar data for the UK in order to identify where and in what respects the social articulations of Australian cultural practices are distinctive. The article draws on the statistical data produced by the Australian Research Council-funded inquiry into Australian Everyday Cultures in the late 1990s and the data produced by the UK’s 2003–6 Economic and Social Research Council inquiry into the relations between cultural capital and social exclusion in Britain. It reports the findings of a comparison of multiple correspondence analyses of the survey data for these two projects. The two spaces of lifestyle produced by these procedures show strong similarities with regard to their relations to class, age and gender as the three most significant axes of differentiation. There are, however, differences in the roles that specific cultural fields (the music, literary and media fields, for example) play relative to one another in the two national contexts. Class culture divisions also appear more attenuated in the Australian than in the British case, with a significant clustering of classes in the middle of the space of lifestyles. However, working-class tastes and those of professionals appear strongly polarised in Australia while managers and professionals are more distinctive in their cultural practices than are their British counterparts.

The Giant Radio Array for Neutrino Detection (GRAND) is a planned array of ~200 000 radio antennas deployed over ~200 000 km2 in a mountainous site. It aims primarly at detecting high-energy neutrinos via the observation of extensive air showers induced by the decay in the atmosphere of taus produced by the interaction of cosmic neutrinos under the Earth surface. GRAND aims at reaching a neutrino sensitivity of 5.10$^{11}$ E$^{-2}$ GeV$^{-1}$cm$^{-2}$s$^{-1}$sr$^{-1}$ above 3.10$^{16}$ eV. This ensures the detection of cosmogenic neutrinos in the most pessimistic source models, and ~50 events per year are expected for the standard models. The instrument will also detect UHECRs and possibly FRBs. Here we show how our preliminary design should enable us to reach our sensitivity goals, and discuss the steps to be taken to achieve GRAND., Comment: 4 pages, 2 figures, proceedings of the ARENA2016 conference

We prove vanishing results for the generalized Miller-Morita-Mumford classes of some smooth bundles whose fiber is a closed manifold that supports a nonpositively curved Riemannian metric. We also find, under some extra conditions, that the vertical tangent bundle is topologically rigid., Comment: 26 pages. We fix a mistake in the proof of Thm G. We thank Oscar Randal-Williams for pointing it out. Changes in some proofs, mainly in Sections 2 and 4. Theorems G an H in older versions are now labeled Lemma 4.4 and Theorem G respectively. Theorem F is stated in more generality. Examples, remarks and references added. We thank the referee for their suggestions

La presente Guía recoge más de cuarenta años de experiencia en la enseñanza de la física dentro del contexto experimental universitario, cuyos propósitos y tendencias pedagógicas han evolucionado a la par con los avances tecnológicos en la medición y la computación. Por tal razón, las metas generales del texto son aproximar al estudiante a la praxis experimental en el ámbito de la física y reproducir dentro del proceso mismo de la mediación educativa una actitud similar a la manera rigurosa y exhaustiva con la cual un investigador profesional, ya en el campo de la ciencia, ejecuta su labor de indagación y generación de conocimiento, por supuesto, en su justa proporción.

Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration and emission. Motivated by present experimental constraints and sensitivities, we improve the predictions of particle emission by investigating time-dependent effects from multiple shocks. We produce synthetic light curves with different variability timescales that stem from properties of the central engine. For individual GRBs, qualitative conclusions about model parameters, neutrino production efficiency, and delays in high-energy gamma rays can be deduced from inspection of the gamma-ray light curves. GRBs with fast time variability without additional prominent pulse structure tend to be efficient neutrino emitters, whereas GRBs with fast variability modulated by a broad pulse structure can be inefficient neutrino emitters and produce delayed high-energy gamma-ray signals. Our results can be applied to quantitative tests of the GRB origin of ultra-high-energy cosmic rays, and have the potential to impact current and future multi-messenger searches., Comment: 24 pages, 15 figures. Improved treatment of shell collisions; minor changes to plots; new plots added. Matches version accepted in ApJ

The origin and composition of ultra-high-energy cosmic rays (UHECRs) remain a mystery. The proton dip model describes their spectral shape in the energy range above $10^9$ GeV by pair production and photohadronic interactions with the cosmic microwave background. The photohadronic interactions also produce cosmogenic neutrinos peaking around $10^9$ GeV. We test whether this model is still viable in light of recent UHECR spectrum measurements from the Telescope Array experiment, and upper limits on the cosmogenic neutrino flux from IceCube. While two-parameter fits have been already presented, we perform a full scan of the three main physical model parameters: source redshift evolution, injected proton maximal energy, and spectral index. We find qualitatively different conclusions compared to earlier two-parameter fits in the literature: a mild preference for a maximal energy cutoff at the sources instead of the Greisen--Zatsepin--Kuzmin (GZK) cutoff, hard injection spectra, and strong source evolution. The predicted cosmogenic neutrino flux exceeds the IceCube limit for any parameter combination. As a result, the proton dip model is challenged at more than 95\% C.L. This is strong evidence against this model independent of mass composition measurements., published in Apj; 15 pages, 12 figures

This review provides a summary of the research conducted on the use of crude glycerol, the major byproduct of the biodiesel industry, as substrate for anaerobic co-digestion and production of biogas. In general, for every 100 kg biodiesel produced, approximately 10 kg crude glycerol is generated. Because this glycerol is expensive to purify for use in food, pharmaceutical, or cosmetic industries, biodiesel producers must seek alternative methods for its disposal. Several studies have demonstrated that the use of crude glycerol as a C source for fermentation and biogas generation is a promising alternative use for this waste material. The high C content of glycerol increases the C:N ratio in the mixture, avoiding the inhibition of the process by the excess of N increasing methane production of digesters by 50 to 200%. Anaerobic co-digestion of glycerol and a variety of residual biomasses may be a good integrated solution for managing these wastes and simultaneously producing a source of bioenergy in an environmentally friendly way. On the other hand, after anaerobic treatment of glycerol, an organic matter-rich solid waste is generated (digestate). The incorporation of digestates from glycerol co-digestion to soils constitutes an important source of organic matter and nutrients for plants. However, the potential of digestates as an organic soil amendment has not been sufficiently studied. The utilization of glycerol as a potential source of energy, rather than as a waste, seems to be a convenient way of lowering the costs of biodiesel production and making this emerging industry more competitive.Esta revisión proporciona un resumen de la investigación realizada sobre el uso de glicerol crudo, principal subproducto de la industria del biodiesel, como sustrato para la co-digestión anaerobia y producción de biogas. En general, por cada 100 kg de biodiesel producido, se generan aproximadamente 10 kg de glicerol. Debido al alto costo de purificación del glicerol para ser utilizado en la industria de alimentos, farmacéutica o cosmética, los productores de biodiesel deben encontrar métodos alternativos de disposición. Varios estudios han demostrado que el uso de glicerol como fuente de C para la fermentación y generación de biogas es una alternativa prometedora para este residuo. El alto contenido de C del glicerol aumenta la relación C:N en la mezcla, evitando la inhibición del proceso por exceso de N, incrementando la producción de metano en los digestores entre 50 a 200%. La co-digestión anaeróbica del glicerol y una variedad de biomasa residual puede ser una solución integrada para gestionar estos residuos y producir una fuente de bioenergía amigable con el medioambiente. Por otra parte, el tratamiento anaeróbico del glicerol genera un residuo sólido rico en materia orgánica (bioabono). La incorporación del bioabono al suelo constituye una importante fuente de nutrientes y materia orgánica para las plantas. Sin embargo, el potencial de estos bioabonos como acondicionadores de suelos no ha sido suficientemente estudiado. La utilización del glicerol como potencial fuente de energía se presenta como una forma adecuada para bajar los costos de producción del biodiesel y hacer más competitiva a esta industria emergente.

We give formulas for the Whitehead groups and the rational $K$-theory groups of the (integer group ring of the) Hilbert modular group in terms of its maximal finite subgroups., 15 pages

La presente guía recoge más de cuarenta años de experiencia en la enseñanza de la física dentro del contexto experimental universitario, cuyos propósitos y tendencias pedagógicas han evolucionado a la par con los avances tecnológicos en la medición y la computación. Por tal razón, las metas generales del texto son aproximar al estudiante a la praxis experimental en el ámbito de la física y reproducir dentro del proceso mismo de la mediación educativa una actitud similar a la manera rigurosa y exhaustiva con la cual un investigador profesional, ya en el campo de la ciencia, ejecuta su labor de indagación y generación de conocimiento, por supuesto, en su justa proporción.

Introduction: From Distinction to distinction studies Part 1: The genesis and career of Distinction 1. Elements for the history of a research: Constructing social space, from "anatomie du gout" to "Distinction" by Monique de Saint-Martin 2. The international career of "Distinction" 3. The intellectual reception of Bourdieu in Australian social sciences and humanities Part 2: The legacy of Distinction in France 4. From " petit-bourgeois " to " petits-moyens ", an invitation to explore short-range upward social mobility 5. Cultural intermediaries: reproduction strategies, resistance to social downgrading and self-fulfilment 6. Continuity and change: Cinematographic tastes in France 7. Culture at the individual level: Questioning the transferability of the habitus dispositions 8. Cultural distinction and material consumption Part 3: Variations on Distinction 9. The Swedish social space of 1990: Investigating its structure and history 10. Constructing social spaces: Scandinavian experiences 11. Cultural Distinctions in an Egalitarian Society 12. Bourdieu's space revisited: The social structuring of lifestyles in Flanders (Belgium) 13. A carnal critique of the judgment of taste: Corpulence, class bodies and symbolic violence 14. The Australian space of lifestyles in comparative perspective 15. The space of cultural practices in Mexico 16. Emerging forms of cultural capital

Gamma-ray bursts are short-lived, luminous explosions at cosmological distances, thought to originate from relativistic jets launched at the deaths of massive stars. They are among the prime candidates to produce the observed cosmic rays at the highest energies. Recent neutrino data have, however, started to constrain this possibility in the simplest models with only one emission zone. In the classical theory of gamma-ray bursts, it is expected that particles are accelerated at mildly relativistic shocks generated by the collisions of material ejected from a central engine. We consider neutrino and cosmic-ray emission from multiple emission regions since these internal collisions must occur at very different radii, from below the photosphere all the way out to the circumburst medium, as a consequence of the efficient dissipation of kinetic energy. We demonstrate that the different messengers originate from different collision radii, which means that multi-messenger observations open windows for revealing the evolving GRB outflows., 12 pages, 7 figures. Matches published version

Gamma-ray bursts (GRBs) have long been held as one of the most promising sources of ultra-high energy (UHE) neutrinos. The internal shock model of GRB emission posits the joint production of UHE cosmic ray (UHECRs, above 10^8 GeV), photons, and neutrinos, through photohadronic interactions between source photons and magnetically-confined energetic protons, that occur when relativistically-expanding matter shells loaded with baryons collide with one another. While neutrino observations by IceCube have now ruled out the simplest version of the internal shock model, we show that a revised calculation of the emission, together with the consideration of the full photohadronic cross section and other particle physics effects, results in a prediction of the prompt GRB neutrino flux that still lies one order of magnitude below the current upper bounds, as recently exemplified by the results from ANTARES. In addition, we show that by allowing protons to directly escape their magnetic confinement without interacting at the source, we are able to partially decouple the cosmic ray and prompt neutrino emission, which grants the freedom to fit the UHECR observations while respecting the neutrino upper bounds. Finally, we briefly present advances towards pinning down the precise relation between UHECRs and UHE neutrinos, including the baryonic loading required to fit UHECR observations, and we will assess the role that very large volume neutrino telescopes play in this., Comment: 4 pages, 2 figures. To be published in Proceedings of the 6th Very Large Volume Neutrino Telescope Workshop (VLVnT13), Stockholm, Sweden, 5-7 August, 2013

Este libro llena un vacío didáctico que se ha percibido en los procesos de formación de estudiantes en los campos de las ciencias aplicadas e ingeniería, y que está estrechamente relacionado con los métodos de análisis básico de datos experimentales, que lo ubican como un libro de referencia y consulta apropiada para los primeros años de estudios universitarios dentro de estos ámbitos del conocimiento. Los cinco capítulos que constituyen el libro abordan las nociones fundamentales básicas del proceso de medición, las cantidades, los sistemas de unidades y equivalencias, para luego ahondar en el tratamiento de los errores e incertidumbres propios de la medición experimental. Asimismo, tiende un puente entre los procesos estadísticos y la actividad experimental en física. Ello busca conducir al estudiante a la construcción de un modelo resultante de los datos obtenidos experimentalmente.

Correction for ‘A sustainable lignocellulosic biodiesel production integrating solar- and bio-power generation’ by Michael Zanotti, et al., Green Chem., 2016, 18, 5059–5068.

We discuss decays of ultra-relativistic neutrinos over cosmological distances by solving the decay equation in terms of its redshift dependence. We demonstrate that there are significant conceptual differences compared to more simplified treatments of neutrino decay. For instance, the maximum distance the neutrinos have traveled is limited by the Hubble length, which means that the common belief that longer neutrino lifetimes can be probed by longer distances does not apply. As a consequence, the neutrino lifetime limit from supernova 1987A cannot be exceeded by high-energy astrophysical neutrinos. We discuss the implications for neutrino spectra and flavor ratios from gamma-ray bursts as one example of extragalactic sources, using up-to-date neutrino flux predictions. If the observation of SN 1987A implies that \nu_1 is stable and the other mass eigenstates decay with rates much smaller than their current bounds, the muon track rate can be substantially suppressed compared to the cascade rate in the region IceCube is most sensitive to. In this scenario, no gamma-ray burst neutrinos may be found using muon tracks even with the full scale experiment, whereas reliable information on high-energy astrophysical sources can only be obtained from cascade measurements. As another consequence, the recently observed two cascade event candidates at PeV energies will not be accompanied by corresponding muon tracks., Comment: 20 pages, 6 figures, 1 table. Matches published version

Water availability is the main limiting factor in arid soils; however, few studies have examined the effects of drying and rewetting on nitrifiers from these environments. The effect of water availability on the diversity of ammonia-oxidizing bacteria (AOB) and archaea (AOA) from a semiarid soil of the Chilean sclerophyllous matorral was determined by microcosm assays. The addition of water every 14 days to reach 60% of the WHC significantly increased nitrate content in rewetted soil microcosms (p < 0.001). This stimulation of net nitrification by water addition was inhibited by acetylene addition at 100 Pa. The composition of AOA and AOB assemblages from the soils microcosms was determined by clone sequencing of amoA genes (A-amoA and B-amoA, respectively), and the 16S rRNA genes specific for β-proteobacteria (beta-amo). Sequencing of beta-amo genes has revealed representatives of Nitrosomonas and Nitrosospira while B-amoA clones consisted only of Nitrosospira sequences. Furthermore, all clones from the archaeal amoA gene library (A-amoA) were related to “mesophilic Crenarchaeota” sequences (actually, reclassified as the phylum Thaumarchaeota). The effect of water availability on both microbial assemblages structure was determined by T-RFLP profiles using the genetic markers amoA for archaea, and beta-amo for bacteria. While AOA showed fluctuations in some T-RFs, AOB structure remained unchanged by water pulses. The relative abundance of AOA and AOB was estimated by the Most Probable Number coupled to Polymerase Chain Reaction (MPN-PCR) assay. AOB was the predominant guild in this soil and higher soil water content did not affect their abundance, in contrast to AOA, which slightly increased under these conditions. Therefore, these results suggest that water addition to these semiarid soil microcosms could favor archaeal contribution to ammonium oxidation.

We have studied the consequences of breaking the CPT symmetry in the neutrino sector, using the expected high-energy neutrino flux from distant cosmological sources such as active galaxies. For this purpose we have assumed three different hypotheses for the neutrino production model, characterised by the flavour fluxes at production phi(0)(e) : phi(0)(mu) : phi(0)(tau) = 1 : 2 : 0, 0 : 1 : 0, and 1 : 0 : 0, and studied the theoretical and experimental expectations for the muon-neutrino flux at Earth, phi(mu), and for the flavour ratios at Earth, R = phi(mu)/phi(e) and S = phi(tau)/phi(mu). CPT violation (CPTV) has been implemented by adding an energy-independent term to the standard neutrino oscillation Hamiltonian. This introduces three new mixing angles, two new eigenvalues and three new phases, all of which have currently unknown values. We have varied the new mixing angles and eigenvalues within certain bounds, together with the parameters associated to pure standard oscillations. Our results indicate that, for the models 1 : 2 : 0 and 0 : 1 : 0, it might be possible to find large deviations of phi(mu), R, and S between the cases without and with CPTV, provided the CPTV eigenvalues lie within 10(-29) - 10(-27) GeV, or above. Moreover, if CPTV exists, there are certain values of R and S that can be accounted for by up to three production models. If no CPTV were observed, we could set limits on the CPTV eigenvalues of the same order. Detection prospects calculated using IceCube suggest that for the models 1 : 2 : 0 and 0 : 1 : 0, the modifications due to CPTV are larger and more clearly separable from the standard-oscillations predictions. We conclude that IceCube is potentially able to detect CPTV but that, depending on the values of the CPTV parameters, there could be a mis-determination of the neutrino production model., This work was supported by grants from the Dirección Académica de Investigación of the Pontificia Universidad Católica del Perú (projects DAI-4075 and DAI-L009 [LUCET]) and by a High Energy Latinamerican-European Network (HELEN) STT grant. MB acknowledges the hospitality of IFIC during the development of this work.

Motivated by the interest in searches for violation of CPT invariance, we study its possible effects in the flavour ratios of high-energy neutrinos coming from cosmic accelerators. In particular, we focus on the effect of an energy independent new physics contribution to the neutrino flavour oscillation phase and explore whether it is observable in future detectors. Such a contribution could be related not only to CPT violation but also to a nonuniversal coupling of neutrinos to a torsion field. We conclude that this extra phase contribution only becomes observable, in the best case, at energies greater than 10^{16.5} GeV, which is about five orders of magnitude higher than the most energetic cosmological neutrinos to be detected in the near future. Therefore, if these effects are present only in the oscillation phase, they are going to be unobservable, unless a new mechanism or source capable to produce neutrinos of such energy were detected., Accepted for publication in the Int. J. Mod. Phys. A -- Typo in online version of abstract corrected

We add an energy-independent Hamiltonian to the standard flavour oscillation one. This kind of physics might appear in theories where neutrinos couple differently to a plausible non-zero torsion of the gravitational field or more dramatically in the presence of CPT-violating physics in the flavour oscillations. If this contribution exists, experiments at higher energies are more sensitive to their free parameters, and flavour conversion could be severely modified. We show that this new physics modifies the neutrino mixing angles and find expressions that relate the new, effective, angles to the standard oscillation parameters \Delta_m_{ij}^2, \theta_{ij} and \delta_{CP}, and to the parameters in the new-physics Hamiltonian, within a three-neutrino formalism. We consider scenarios where the new parameters allow for extreme deviations of the expected neutrino flavour ratios at Earth from their standard values. We show that large departures of the standard flavour scenario are plausible, which would be a strong hint of the violation of a conserved symmetry., Comment: 10 pages, To appear in the proceedings of DISCRETE'08: Symposium on Prospects in the Physics of Discrete Symmetries, Valencia, Spain, 11-16 Dec 2008

We propose searching for deep underground cavities of different densities in the Earth’s crust using a long-baseline [Formula: see text] disappearance experiment, realized through a low-energy [Formula: see text]-beam with highly-enhanced luminosity. We focus on four cases: cavities with densities close to that of water, iron-banded formations, heavier mineral deposits, and regions of abnormal charge accumulation that have been posited to appear prior to the occurrence of an intense earthquake. The sensitivity to identify cavities attains confidence levels (C.L.s) higher than [Formula: see text] and [Formula: see text] for exposure times of three months and 1.5 years, respectively, and cavity densities below [Formula: see text] or above [Formula: see text], with widths greater than 200 km. We reconstruct the cavity density, width, and position, assuming one of them known while keeping the other two free. We obtain large allowed regions that improve as the cavity density differs more from the Earth’s mean density. Furthermore, we demonstrate that the knowledge of the cavity density is important to obtain O(10%) error on the width. Finally, we introduce an observable to quantify the presence of a cavity by changing the orientation of the [Formula: see text] beam, with which we are able to identify the presence of a cavity at the [Formula: see text] to [Formula: see text] C.L.

Des les annees 1960, l’Unesco a joue un role tres actif dans la constitution d’espaces de discussion sur les politiques culturelles au niveau international. En realisant a l’epoque un etat des lieux international de ces politiques, l’Unesco a contribue a la formation d’un espace de debats, de references partagees, d’echange de savoirs et savoir-faire, qui ont favorise la consolidation et la legitimation de la politique culturelle nationale comme norme largement admise. Cet article compare les actions culturelles d’une centaine de pays, en les confrontant aux enjeux socio-economiques, geopolitiques et culturels des annees 1980, ce qui permet de ne pas apprehender les politiques culturelles seulement comme un domaine confine aux rapports de force des champs de pouvoir nationaux. Les poles d’opposition qui se degagent refractent bien souvent des antagonismes preexistants et exterieurs a la seule dimension culturelle de l’action publique.

The paradigm that gamma-ray burst fireballs are the sources of the ultra-high energy cosmic rays (UHECRs) is being probed by neutrino observations. Very stringent bounds can be obtained from the cosmic-ray (proton)-neutrino connection, assuming that the UHECRs escape as neutrons. In this study, we identify three different regimes as a function of the fireball parameters: the standard one neutrino per cosmic ray case, the optically thick (to neutron escape) case, and the case where leakage of protons from the boundaries of the shells (direct escape) dominates. In the optically thick regime, the photomeson production is very efficient, and more neutrinos will be emitted per cosmic ray than in the standard case, whereas in the direct escape-dominated regime, more cosmic rays than neutrinos will be emitted. We demonstrate that, for efficient proton acceleration, which is required to describe the observed UHECR spectrum, the standard case only applies to a very narrow region of the fireball parameter space. We illustrate with several observed examples that conclusions on the cosmic-ray-neutrino connection will depend on the actual burst parameters. We also show that the definition of the pion production efficiency currently used by the IceCube collaboration underestimates the neutrino production in the optically thick case. Finally, we point out that the direct escape component leads to a spectral break in the cosmic-ray spectrum emitted from a single source. The resulting two-component model can be used to even more strongly pronounce the spectral features of the observed UHECR spectrum than the dip model.

El objetivo fue comparar, en cuanto a productividad en materia seca y captura de carbono, entre un sistema silvopastoril y un sistema tradicional en cinco fincas ganaderas de piedemonte del departamento de Casanare. En el lote experimental de cada finca se sembró una mezcla de cuatro especies de pastos, de los cuales Brachiaria brizantha fue la especie que tuvo un desarrollo exitoso en las cinco fincas, y con la cual se analizó su productividad en materia seca y captura de carbono. A los cinco meses después de la renovación de pastos en los lotes experimentales se obtuvo una productividad en materia seca entre 6,3 y 14,9 tMS/ha, y en captura de carbono entre 2,7 y 6,4 tCOT/ha; mientras que en los lotes tradicionales estuvo entre 4 y 5 tMS/ha, y en captura de carbono entre 1,7 y 2,9 tCOT/ha. A los 20 meses en los lotes experimentales se obtuvo una productividad en materia seca entre 12 y 13,7 tMS/ha, y en captura de carbono entre 4,1 y 4,5 tCOT/ha; mientras que en los lotes tradicionales estuvo entre 4,4 y 6,5 tMS/ha, y en captura de carbono entre 1,4 y 2,1 tCOT/ha. Esto indica que la renovación de praderas con pastos adecuados y el pastoreo de rotación favorecen la producción en materia seca y la captura de carbono.