The Nova V5584 Sgr: A Short Review

The nova V5584 Sgr was discovered during 2009 October. It has been monitored in different domains of the electromagnetic spectrum: optical, infrared and X-rays. The optical and infrared observations suggest that V5584 Sgr is a Fe II nova that formed dust. No X-ray emission was observed around the time of maximum

Inertial control of the mirror suspensions of the VIRGO interferometer for gravitational wave detection

In order to achieve full detection sensitivity at low frequencies, the mirrors of interferometric gravitational wave detectors must be isolated from seismic noise. The VIRGO vibration isolator, called 'superattenuator', is fully effective at frequencies above 4 Hz. Nevertheless, the residual motion of the mirror at the mechanical resonant frequencies of the system are too large for the interferometer locking system and must be damped. A multidimensional feedback system, using inertial sensors and digital processing, has been designed for this purpose. An experimental procedure for determining the feedback control of the system has been defined. In this paper a full description of the system is given and experimental results are presented.Comment: 17 pages, 11 figures, accepted for publication on Review of Scientific Instrument

Gravitational physics with antimatter

The production of low-energy antimatter provides unique opportunities to search for new physics in an unexplored regime. Testing gravitational interactions with antimatter is one such opportunity. Here a scenario based on Lorentz and CPT violation in the Standard- Model Extension is considered in which anomalous gravitational effects in antimatter could arise.Comment: 5 pages, presented at the International Conference on Exotic Atoms (EXA 2008) and the 9th International Conference on Low Energy Antiproton Physics (LEAP 2008), Vienna, Austria, September 200

Análise foliar em cinco espécies de eucaliptos

Two hundred recent mature leaves were collected, at april 1976, from each of the upper crown part of to years old plants (E. grandis, E. microcorys, E. resinifera, E.robusta, E. saligna), established on two Red Yellow Latossol site at Mogi Guaçu and Areia Branca, State of São Paulo, Brasil. Chemical analysis were run for N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn in order to detect nutritional differences between the species. The highest concentration of N, P, K and S were founded in E. grandis; while E. microcorys exhibited the lowest concentrations in nutrients. High eleveis in Mn were observed in all species due the acid soils. The yields in (m³/ha.) of wood have varied considerably within the species. The higher production of wood was of the species E. grandis and the lower was due E. microcorys. A positive correlation were observed between nutrient concentration (x) and yield of wood (y) for the elements and is expressed by the following equations: Ny = 261.45 x - 158.51 r = 0.60** Py = 4.476.80 x - 126.24 r = 0.60** Ky = 715.27 x- 1.76 r = 0.58** Sy = 1.431.74 x - 2.13 r = 0.51** Fe y = 2.773.2 x+ 48.63 r = 0.34*Foram coletadas 200 folhas recem maduras de meia altura (H = 11 m) da copa das espécies E. graandis, E. microcorys, E. saligna de sete anos de idade, localizadas em solo latossolo, na região de Mogi Guaçu e Areia Branca, SP. As folhas foram analisadas para N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn com os objetivos de detectar exigências nutricionais distintas para as espécies, assim como correlacionar o teor dos nutrientes com o volume cilíndrico de madeira (m³/ha). Constatou-se diferenças significativas na composição química entre as espécies. A espécie E. granais apresenta um teor mais elevado em N, P, K e S. As concentrações mais baixas dos nutrientes são encontradas no E. microcorys. Foram constatadas diferenças significativas entre os locais nas espécies com exceção de Mg, B, Cu, Fe e Zn. Teores elevados em Mn foram constatados nas folhas de todas as espécies. O eucalipto de maior produção é o E. grandis, sendo o E. microcorys o de menor produção. Foi constatada correlação positiva entre N, P, K, S e Fe nas folhas e produção cilíndrica de madeira

Chandra High Energy Transmission Gratings Spectra of V3890 Sgr

The recurrent nova (RN) V3890 Sgr was observed during the 7th day after the onset of its most recent outburst, with the Chandra ACIS-S camera and High Energy Transmission Gratings (HETG). A rich emission line spectrum was detected, due to transitions of Fe-L and K-shell ions ranging from neon to iron. The measured absorbed flux is $\approx 10^{-10}$ erg cm$^{-2}$ s$^{-1}$ in the 1.4-15 Angstrom range (0.77-8.86 keV). The line profiles are asymmetric, blue-shifted and skewed towards the blue side, as if the ejecta moving towards us are less absorbed than the receding ones. The full width at half maximum of most emission lines is 1000-1200 km s$^{-1}$, with some extended blue wings. The spectrum is thermal and consistent with a plasma in collisional ionization equilibrium with column density 1.3 $\times 10^{22}$ cm$^{-2}$ and at least two components at temperatures of about 1 keV and 4 keV, possibly a forward and a reverse shock, or regions with differently mixed ejecta and red giant wind. The spectrum is remarkably similar to the symbiotic RNe V745 Sco and RS Oph, but we cannot distinguish whether the shocks occurred at a distance of few AU from the red giant, or near the giant's photosphere, in a high density medium containing only a small mass. The ratios of the flux in lines of aluminum, magnesium and neon relative to the flux in lines of silicon and iron probably indicate a carbon-oxygen white dwarf (CO WD)

The nature of the intra-night optical variability in blazars

In this paper we present results of a short-term optical monitoring of 13 blazars. The objects were monitored mostly in the R-band for a total of ~ 160 hours between 2006 and 2011. We study the nature of the short-term variations and show that most of them could be described as slow, smooth, and (almost) linear changes of up to ~ 0.1 mag/hour, but many objects show no short-term variations at all. In fact, we found only ~ 2 per cent chance to observe variability of more than 0.1 mag/hour for the sample we observed. Hints for quasi-periodic oscillations at very low amplitude levels are also found for some objects. We briefly discuss some of the possible mechanisms to generate the intra-night variability and the quasi-periodic oscillations.Comment: 10 pages, 13 figures, 1 table, Accepted for Publication in MNRA

Virgo calibration and reconstruction of the gravitational wave strain during VSR1

Virgo is a kilometer-length interferometer for gravitational waves detection located near Pisa. Its first science run, VSR1, occured from May to October 2007. The aims of the calibration are to measure the detector sensitivity and to reconstruct the time series of the gravitational wave strain h(t). The absolute length calibration is based on an original non-linear reconstruction of the differential arm length variations in free swinging Michelson configurations. It uses the laser wavelength as length standard. This method is used to calibrate the frequency dependent response of the Virgo mirror actuators and derive the detector in-loop response and sensitivity within ~5%. The principle of the strain reconstruction is highlighted and the h(t) systematic errors are estimated. A photon calibrator is used to check the sign of h(t). The reconstructed h(t) during VSR1 is valid from 10 Hz up to 10 kHz with systematic errors estimated to 6% in amplitude. The phase error is estimated to be 70 mrad below 1.9 kHz and 6 micro-seconds above.Comment: 8 pages, 8 figures, proceedings of Amaldi 8 conference, to be published in Journal of Physics Conference Series (JPCS). Second release: correct typo

Biopsia tendínea em equinos com tendões hígidos e com tendinite agura induzida pela colagenase: estudo preliminar

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Scientific Potential of Einstein Telescope

Einstein gravitational-wave Telescope (ET) is a design study funded by the European Commission to explore the technological challenges of and scientific benefits from building a third generation gravitational wave detector. The three-year study, which concluded earlier this year, has formulated the conceptual design of an observatory that can support the implementation of new technology for the next two to three decades. The goal of this talk is to introduce the audience to the overall aims and objectives of the project and to enumerate ET's potential to influence our understanding of fundamental physics, astrophysics and cosmology.Comment: Conforms to conference proceedings, several author names correcte