Doubly-charged particles at the Large Hadron Collider

In this work we investigate the production and signatures of doubly-charged particles at the Large Hadron Collider. We start with the Standard Model particle content and representations and add generic doubly-charged exotic particles. We classify these doubly-charged states according to their spin, considering scalar, fermionic and vectorial fields, and according to their SU(2)L representation, being chosen to be either trivial, fundamental, or adjoint. We write the most general interactions between them and the Standard Model sector and study their production modes and possible decay channels. We then probe how they can most likely be observed and how particles with different spin and SU(2)L representations could be possibly distinguished.Comment: 18 pages, 8 figures, 1 table; version accepted by Phys.Rev.

Solitons in generalized galileon theories

We consider the existence and stability of solitons in generalized galileons, scalar field theories with higher-derivative interactions but second-order equations of motion. It has previously been proven that no stable, static solitons exist in a single galileon theory using an argument invoking the existence of zero modes for the perturbations. Here we analyze the applicability of this argument to generalized galileons and discuss how this may be avoided by having potential terms in the energy functional for the perturbations, or by including time dependence. Given the presence of potential terms in the Lagrangian for the perturbations, we find that stable, static solitons are not ruled out in conformal and (A)dS galileons. For the case of DBI and conformal galileons, we find that solitonic solutions moving at the speed of light exist, the former being stable and the latter unstable if the background soliton satisfies a certain condition.Comment: 28 page

RUST: A Retargetable Usability Testbed for Website Authentication Technologies

Website authentication technologies attempt to make the identity of a website clear to the user, by supplying information about the identity of the website. In practice however, usability issues can prevent users from correctly identifying the websites they are interacting with. To help identify usability issues we present RUST, a Retargetable USability Testbed for website authentication technologies. RUST is a testbed that consists of a test harness, which provides the ability to easily configure the environment for running usability study sessions, and a usability study design that evaluates usability based on spoofability, learnability, and acceptability. We present data collected by RUST and discuss preliminary results for two authentication technologies, Microsoft CardSpace and Verisign Secure Letterhead. Based on the data collected, we conclude that the testbed is useful for gathering data on a variety of technologies

Discordance in cathepsin B and cystatin C expressions in bronchoalveolar fluids between murine bleomycin-induced fibrosis and human idiopathic fibrosis

International audienceAbstractThe activity of cysteine cathepsin B increased markedly in lung homogenates and in bronchoalveolar lavage fluids (BALF) of the mouse model of bleomycin-induced lung fibrosis after 14 days of challenge. In contrast the level of the cysteine cathepsin inhibitor cystatin C was unaffected in BALF of wild-type and cathepsin B-deficient mice. Therefore, murine cystatin C is not a reliable marker of fibrosis during bleomycin-induced lung fibrosis. Current data are in sharp contrast to previous analysis carried on human BALF from patients with idiopathic pulmonary fibrosis, for which the level of cathepsin B remained unchanged while cystatin C was significantly increased

JRC Ispra EMEP - GAW Regional Station for Atmospheric Research 2008 Report

The aim of the JRC-Ispra station for atmospheric research (45°49'N, 8°38'E) is to monitor atmospheric parameters (pollutant concentrations and fluxes, atmospheric particle chemical composition, number size distribution and optical properties) to contribute in assessing the impact of European policies on air pollution and climate change. The station has been operated continuously since November 1985, with a gap in gas phase data due to a severe breakdown of the data acquisition system in 2003 though. The measurements performed in 2008 led to annual averages of ca. 34 µg m-3 O3, 0.7 µg m-3 SO2, 20 µg m-3 NO2 and 27 µg m-3 PM10. Carbonaceous species (organic matter plus elemental carbon) are the main constituents of PM2.5 (~57 %) followed by NH4NO3 (20-30 %) and (NH4)2SO4 (10-20 %). The data from 2008 confirmed the seasonal variations observed over the previous years, mainly driven by meteorology rather than by changes in emissions, as revealed by the lidar measurements. Aerosol physical and optical properties were also measured in 2008. The average particle number (from 10 nm to 10 µm) was about 8000 cm-3 in 2008. The mean (close to dry) aerosol single scattering albedo (0.75) was low compared to the values generally observed in Europe, which means that the cooling effect of aerosols is reduced in our region compared to others. Long-term trends (over 20 years) show consistent decreases in sulfur concentrations and deposition, PM mass concentration (-0.9 µg m-3 yr-1), and from 2003 in ozone concentrations too. The decreasing trends in oxidised and reduced nitrogen species are much less pronounced.JRC.H.2 - Climate chang

JRC Ispra EMEP - GAW Regional Station for Atmospheric Research, 2009 Report

The aim of the JRC-Ispra station for atmospheric research (45°49¿N, 8°38¿E) is to monitor atmospheric parameters (pollutant concentrations and fluxes, atmospheric particle chemical composition, number size distribution and optical properties) to contribute in assessing the impact of European policies on air pollution and climate change. The station has been operated continuously since November 1985, with a gap in gas phase data in 2003 and 2009 due to a breakdown of the data acquisition system and lack of man-power, respectively. The measurements performed in 2009 led to annual average of 26.8 µg m-3 for PM10, well below the European annual limit value of 40 µg/m³ (the European directive 1999/30/EC for the year 2005 and onwards). In addition, the measurements performed in 2009 led to annual average of 19.0 µg m-3 for PM2.5, well below the future European annual limit value of 25 µg/m³ (European directive 2008/50/EC for the year 2015 and onwards). Carbonaceous species (organic matter plus elemental carbon) are the main constituents of PM2.5 (~57 %) followed by (NH4)2SO4 (24 %) and NH4NO3 (12 %). The data from 2009 confirmed the seasonal variations observed over the previous years, mainly driven by meteorology rather than by changes in emissions, as revealed by the lidar measurements. Aerosol physical and optical properties were also measured in 2009. The average particle number (from 10 nm to 10 µm) was about 7400 cm-3 and the mean geometric diameter was 70 nm. Their hygroscopic growth at 90% RH varies from <1.2 in December to 1.25 ¿ 1.35 (size dependent) in June. The mean (close to dry) aerosol single scattering albedo at ¿ = 550 nm was 0.76, and it was low compared to the values generally observed in Europe, which means that the cooling effect of aerosols is reduced in our region compared to others. Long-term trends (over 20 years) show consistent decreases in sulfur concentrations and deposition, PM mass concentration (about -0.9 µg m-3 yr-1), and from 2003 onwards also a slight decease in ozone concentrations too. The decreasing trends in oxidised and reduced nitrogen species are much less pronounced.JRC.DDG.H.2-Climate change and air qualit

Submillimeter Array Observations of the RX J1633.9-2442 Transition Disk: Evidence for Multiple Planets in the Making

We present continuum high resolution Submillimeter Array (SMA) observations of the transition disk object RX J1633.9-2442, which is located in the Ophiuchus molecular cloud and has recently been identified as a likely site of ongoing giant planet formation. The observations were taken at 340 GHz (880 micron) with the SMA in its most extended configuration, resulting in an angular resolution of 0.3" (35 AU at the distance of the target). We find that the disk is highly inclined (i ~50 deg) and has an inner cavity ~25 AU in radius, which is clearly resolved by our observations. We simultaneously model the entire optical to millimeter wavelength spectral energy distribution (SED) and SMA visibilities of RX J1633.9-2442 in order to constrain the structure of its disk. We find that an empty cavity ~25 AU in radius is inconsistent with the excess emission observed at 12, 22, and 24 micron. Instead, the mid-IR excess can be modeled by either a narrow, optically thick ring at ~10 AU or an optically thin region extending from ~7 AU to ~25 AU. The inner disk (r < 5 AU) is mostly depleted of small dust grains as attested by the lack of detectable near-IR excess. We also present deep Keck aperture masking observations in the near-IR, which rule out the presence of a companion up to 500 times fainter than the primary star (in K-band) for projected separations in the 5-20 AU range. We argue that the complex structure of the RX J1633.9-2442 disk is best explained by multiple planets embedded within the disk. We also suggest that the properties and incidence of objects such as RX J1633.9-2442, T Cha, and LkCa 15 (and those of the companions recently identified to these two latter objects) are most consistent with the runaway gas accretion phase of the core accretion model, when giant planets gain their envelopes and suddenly become massive enough to open wide gaps in the disk.Comment: Accepted for publication in Ap

Coalescent-based species delimitation in the sand lizards of the Liolaemus wiegmannii complex (Squamata: Liolaemidae)

Coalescent-based algorithms coupled with the access to genome-wide data have become powerful tools forassessing questions on recent or rapid diversification, as well as delineating species boundaries in the absence of reciprocal monophyly. In southern South America, the diversification of Liolaemus lizards during the Pleistocene is well documented and has been attributed to the climatic changes that characterized this recent period of time. Past climatic changes had harsh effects at extreme latitudes, including Patagonia, but habitat changes at intermediate latitudes of South America have also been recorded, including expansion of sand fields over northern Patagonia and Pampas). In this work, we apply a coalescent-based approach to study the diversification of the Liolaemus wiegmannii species complex, a morphologically conservative clade that inhabits sandy soils across northwest and south-central Argentina, and the south shores of Uruguay. Using four standard sequence markers (mitochondrial DNA and three nuclear loci) along with ddRADseq data we inferred species limits and a time calibrated species tree for the L. wiegmannii complex in order to evaluate the influence of Quaternary sand expansion/retraction cycles on diversification. We also evaluated the evolutionary independence of the recently described L. gardeli and inferred its phylogenetic position relative to L. wiegmannii. We find strong evidence for six allopatric candidate species within L. wiegmannii, which diversified during the Pleistocene. The Great Patagonian Glaciation (∼1 million years before present) likely split the species complex into two main groups: one composed of lineages associated with sub-Andean sedimentary formations, and the other mostly related to sand fields in the Pampas and northern Patagonia. We hypothesize that early speciation within L. wiegmannii was influenced by the expansion of sand dunes throughout central Argentina and Pampas. Finally, L. gardeli is supported as a distinct lineage nested within the L. wiegmannii complex.Fil: Villamil, Joaquín. Universidad de la República. Facultad de Ciencias; UruguayFil: Avila, Luciano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Morando, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Sites, Jack W.. University Brigham Young; Estados UnidosFil: Leaché, Adam D.. University of Washington; Estados UnidosFil: Maneyro, Raúl. Universidad de la República. Facultad de Ciencias; UruguayFil: Camargo Bentaberry, Arley. Universidad de la República; Urugua