JUNO Conceptual Design Report

The Jiangmen Underground Neutrino Observatory (JUNO) is proposed to determine the neutrino mass hierarchy using an underground liquid scintillator detector. It is located 53 km away from both Yangjiang and Taishan Nuclear Power Plants in Guangdong, China. The experimental hall, spanning more than 50 meters, is under a granite mountain of over 700 m overburden. Within six years of running, the detection of reactor antineutrinos can resolve the neutrino mass hierarchy at a confidence level of 3-4$\sigma$, and determine neutrino oscillation parameters $\sin^2\theta_{12}$, $\Delta m^2_{21}$, and $|\Delta m^2_{ee}|$ to an accuracy of better than 1%. The JUNO detector can be also used to study terrestrial and extra-terrestrial neutrinos and new physics beyond the Standard Model. The central detector contains 20,000 tons liquid scintillator with an acrylic sphere of 35 m in diameter. $\sim$17,000 508-mm diameter PMTs with high quantum efficiency provide $\sim$75% optical coverage. The current choice of the liquid scintillator is: linear alkyl benzene (LAB) as the solvent, plus PPO as the scintillation fluor and a wavelength-shifter (Bis-MSB). The number of detected photoelectrons per MeV is larger than 1,100 and the energy resolution is expected to be 3% at 1 MeV. The calibration system is designed to deploy multiple sources to cover the entire energy range of reactor antineutrinos, and to achieve a full-volume position coverage inside the detector. The veto system is used for muon detection, muon induced background study and reduction. It consists of a Water Cherenkov detector and a Top Tracker system. The readout system, the detector control system and the offline system insure efficient and stable data acquisition and processing.Comment: 328 pages, 211 figure

Search for supersymmetry via associated production of charginos and neutralinos in final states with three leptons

A search for associated production of charginos and neutralinos is performed using data recorded with the D0 detector at a p (p) over bar center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. This analysis considers final states with missing transverse energy and three charged leptons, of which at least two are electrons or muons. No evidence for supersymmetry is found in a data set corresponding to an integrated luminosity of 320 pb(-1). Limits on the product of the production cross section and leptonic branching fraction are set. For the minimal supergravity model, a chargino lower mass limit of 117 GeV at the 95% C.L. is derived in regions of parameter space with enhanced leptonic branching fractions

Caballero Bonald : 'José Agustín Goytisolo ansiaba ser seductor'

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Measurement of sigma(p(p)over-bar -> Z)center dot Br(Z ->tau tau) at root s=1.96 TeV (vol 71, art no. 072004, 2005)

A change in estimated integrated luminosity (from 226 pb$^{-1} to 257 pb$^{-1}$leads to a corrected value for${\sigma (p \bar p \to Z) \cdot}$Br${(Z \to \tau \tau)}$of$209\pm13(stat.)\pm16(syst.)\pm13(lum) pb

European Venus Explorer: An in-situ mission to Venus using a balloon platform

International audiencePlanetary balloons have a long history already. A small super-pressure balloon was flown in the atmosphere of Venus in the eighties by the Russian-French VEGA mission. For this mission, CNES developed and fully tested a 9 m diameter super-pressure balloon, but finally replaced it by a smaller one due to mass constraints (when it was decided to send Vega to Halley’s Comet). Furthermore, several kinds of balloons have been proposed for planetary exploration [Blamont, J., in: Maran, S.P. (Ed.), The Astronomy and Astrophysics Encyclopedia. Cambridge University Press, p. 494, 1991]. A Mars balloon has been studied for the Mars-94 Russian-French mission, which was finally cancelled. Mars and Venus balloons have also been studied and ground tested at JPL, and a low atmosphere Venus balloon is presently under development at JAXA (the Japanese Space Agency). Balloons have been identified as a key element in an ongoing Flagship class mission study at NASA, with an assumed launch date between 2020 and 2025.Recently, it was proposed by a group of scientists, under European leadership, to use a balloon to characterize – by in-situ measurements – the evolution, composition and dynamics of the Venus atmosphere. This balloon is part of a mission called EVE (European Venus Explorer), which has been proposed in response to the ESA AO for the first slice of the Cosmic Vision program by a wide international consortium including Europe, Russia, Japan and USA. The EVE architecture consists of one balloon platform floating at an altitude of 50–60 km, one short lived probe provided by Russia, and an orbiter with a polar orbit to relay data from the balloon and probe, and to perform remote sensing science observations. The balloon type preferred for scientific goals is one, which would oscillate in altitude through the cloud deck. To achieve this flight profile, the balloon envelope would contain a phase change fluid. While this proposal was not selected for the first slice of Cosmic Vision missions, it was ranked first among the remaining concepts within the field of solar system science

European Venus Explorer (EVE): an in-situ mission to Venus

The European Venus Explorer (EVE) mission was proposed to the European Space Agency in 2007, as an M-class mission under the Cosmic Vision Programme. Although it has not been chosen in the 2007 selection round for programmatic reasons, the EVE mission may serve as a useful reference point for future missions, so it is described here. It consists of one balloon platform floating at an altitude of 50-60 km, one descent probe provided by Russia, and an orbiter with a polar orbit which will relay data from the balloon and descent probe, and perform science observations. The balloon type preferred for scientific goals is one which oscillates in altitude through the cloud deck. To achieve this flight profile, the balloon envelope contains a phase change fluid, which results in a flight profile which oscillates in height. The nominal balloon lifetime is 7 days-enough for one full circumnavigation of the planet. The descent probe's fall through the atmosphere takes 60 min, followed by 30 min of operation on the surface. The key measurement objectives of EVE are: (1) in situ measurement from the balloon of noble gas abundances and stable isotope ratios, to study the record of the evolution of Venus; (2) in situ balloon-borne measurement of cloud particle and gas composition, and their spatial variation, to understand the complex cloud-level chemistry; (3) in situ measurements of environmental parameters and winds (from tracking of the balloon) for one rotation around the planet, to understand atmospheric dynamics and radiative balance in this crucial region. The portfolio of key measurements is complemented by the Russian descent probe, which enables the investigation of the deep atmosphere and surface. © Springer Science+Business Media B.V. 2008

Search for particles decaying into a Z boson and a photon in p(p)over-bar collisions at root s=1.96 TeV

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Temperature, Clouds, and Aerosols in the Terrestrial Bodies of the Solar System

International audienceThis chapter is intended to provide a concise overview of the state of knowledge regarding the temperature, clouds, and aerosols of the terrestrial bodies of our Solar System, namely Mars, Venus, and Titan. These bodies are the planetary objects that most resemble the Earth. The atmosphere of each body is described in terms of composition and vertical structure. We distinguish and compare the extent of the various atmospheric compartments that form the atmospheric column, from the troposphere up to the thermosphere. The temperature structure is then presented, and the main causes known for explaining its variations on each body are listed. The specific roles of waves, radiation, as well as convection in shaping temperature profiles are then discussed. In a second part, the particulate components of these atmospheres, clouds and aerosols, are described in terms of their physical properties (composition, optical properties) and of their variability in both space and time. Mars , Venus, and Titan exhibit a remarkable variety of clouds and aerosols. Our knowledge about them has made considerable progress thanks to the success of space missions during the last two decades, while in parallel theoretical models have improved to the point that three-dimensional Global Climate Models now include the detailed physics of clouds and aerosols. As a result, it is now widely recognized that particulates play a key role in forcing the climate and the evolution of these bodies