Multivacuum states in a fermionic gap equation with massive gluons and confinement

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Massive spin-2 theories in arbitrary D>= 3 dimensions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dual descriptions of massive spin-3 particles in D=2+1 via Noether gauge embedment

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Massive spin-2 particles via embedment of the Fierz-Pauli equations of motion

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Planet formation in a triple stellar system: implications of the third star's orbital inclination

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Celestial mechanics: from the errant stars to guidance of spacecrafts

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pseudoaneurysm of the internal carotid artery presenting with massive (recurrent) epistaxes: a life-threatening complication of craniofacial trauma

Vascular lesions can be serious complications resulting of blunt or penetrating trauma(1,2). Internal carotid artery lesion is one of most serious and relatively frequent in all mechanisms of craniofacial trauma. Several clinical manifestations can occur as central neurologic and cranial nerves deficits as well as several degrees of bleeding (from mild symptomatic to fatal). Recurrent and massive epistaxis can occur after trauma due to pseudaoneurysms of the external and internal carotid artery (ICA)(3,4). Considering its life-threatening course, the assisting physician has a relatively narrow time to detect and treat these lesions.We present two cases of recurrent and massive epistaxis secondary to ICA pseudoaneurysm following blunt and perforating trauma. Evolution was fatal in the first case with delayed treatment and uneventfully in the second which was treated by occlusion of the pseudoaneurysm and ICA via endovascular intervention.

Acute kidney injury after massive attack of Africanised bees

Acute kidney injury (AKI) is a well-documented complication of massive attack by Africanised bees and can be observed 48-72 h after the accident. We report a case of Africanised bees attack followed by severe and lethal AKI. A 56-year-old man was admitted to emergency department after a massive attack of Africanised bees (>1000 bee stings). He was unconscious, presenting with hypotension and tachycardia. Mechanical ventilation, volume expansion and care for anaphylaxis were instituted. The patient was transferred to the intensive care unit (ICU) and after 48 h he developed rhabdomyolysis, oliguria, increased creatinine levels, hyperkalaemia and refractory acidosis. A diagnosis of AKI secondary to rhabdomyolysis and shock was made. The patient was treated with a prolonged course of haemodialysis. However, he progressed to refractory shock and died 5 days after admission.

Medium effects in the pion-pole mechanism [gamma gamma ->pi(0)->nu(R)(nu)over-bar(L)(nu(L)(nu)over-bar(R))] of neutron star cooling

Nuclear medium effects in the neutrino cooling of neutron stars through the reaction channel γγ→π0 →ν Rν̄L(νLν̄R) are incorporated. Throughout the paper we discuss different possibilities of right-handed neutrinos, massive left-handed neutrinos, and standard massless left-handed neutrinos (reaction is then allowed only with medium modified vertices). It is demonstrated that multiparticle effects suppress the rate of this reaction channel in the dense hadron matter by 6-7 orders of magnitude that does not allow to decrease existing experimental upper limit on the corresponding π0νν̄ coupling. Other possibilities of the manifestation of the given reaction channel in different physical situations, e.g., in the quark color superconducting cores of the most massive neutron stars, are also discussed. We demonstrate that in the color-flavor-locked superconducting phase for temperatures T≲ 0.1-10 MeV (depending on the effective pion mass and the decay width) the process is feasibly the most efficient neutrino cooling process, although the absolute value of the reaction rate is rather small.

Imaginary irishness: the feminine in dramatisations of the Paster Rising in Sean O’Casey’s the plough and the stars and Tom Murphy’s The Patriot Game

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A cyclic bipolar wind in the interacting binary V 393 Scorpii

V393 Scorpii is a double periodic variable characterized by a relatively stable non-orbital photometric cycle of 253 d. Mennickent et al. argue for the presence of a massive optically thick disc around the more massive B-type component and describe the evolutionary stage of the system. In this paper, we analyse the behaviour of the main spectroscopic optical lines during the long non-orbital photometric cycle. We study the radial velocity of the donor determining its orbital elements and find a small but significant orbital eccentricity (e = 0.04). The donor spectral features are modelled and removed from the spectrum at every observing epoch using the light-curve model given by Mennickent et al. We find that the line emission is larger during eclipses and mostly comes from a bipolar wind. We also find that the long cycle is explained in terms of a modulation of the wind strength; the wind has a larger line and continuum emissivity at the high state. We report the discovery of highly variable chromospheric emission in the donor, as revealed by the Doppler maps of the emission lines Mg II 4481 and C I 6588. We discuss notable and some novel spectroscopic features like discrete absorption components, especially visible at blue depressed O I 7773 absorption wings during the second half-cycle, Balmer double emission with V/R curves showing 'Z-type' and 'S-type' excursions around secondary and main eclipses, respectively, and H beta emission wings extending up to +/- 2000 km s(-1). We also discuss possible causes for these phenomena and for their modulations with the long cycle.

Particle creation due to tachyonic instability in relativistic stars

Dense enough compact objects were recently shown to lead to an exponentially fast increase of the vacuum energy density for some free scalar fields properly coupled to the spacetime curvature as a consequence of a tachyonic-like instability. Once the effect is triggered, the star energy density would be overwhelmed by the vacuum energy density in a few milliseconds. This demands that eventually geometry and field evolve to a new configuration to bring the vacuum back to a stationary regime. Here, we show that the vacuum fluctuations built up during the unstable epoch lead to particle creation in the final stationary state when the tachyonic instability ceases. The amount of created particles depends mostly on the duration of the unstable epoch and final stationary configuration, which are open issues at this point. We emphasize that the particle creation coming from the tachyonic instability will occur even in the adiabatic limit, where the spacetime geometry changes arbitrarily slowly, and therefore is quite distinct from the usual particle creation due to the change in the background geometry.

NGC 2782: a merger remnant with young stars in its gaseous tidal tail

We have searched for young star-forming regions around the merger remnant NGC 2782. By using Galaxy Evolution Explorer far-ultraviolet and near-ultraviolet imaging and H i data we found seven ultraviolet sources, located at distances greater than 26 kpc from the centre of NGC 2782, and coinciding with its western H i tidal tail. These regions were resolved in several smaller systems when Gemini/Gemini multi-object spectrograph (GMOS) r-band images were used. We compared the observed colours to stellar population synthesis models and found that these objects have ages of similar to 1 to 11 Myr and masses ranging from 103.9 to 104.6 M circle dot. By using Gemini/GMOS spectroscopic data we confirm memberships and derive high metallicities for three of the young regions in the tail (12+log(O/H) = 8.74 +/- 0.20, 8.81 +/- 0.20 and 8.78 +/- 0.20). These metallicities are similar to the value presented by the nuclear region of NGC 2782 and also similar to the value presented for an object located close to the main body of NGC 2782. The high metallicities measured for the star-forming regions in the gaseous tidal tail of NGC 2782 could be explained if they were formed out of highly enriched gas which was once expelled from the centre of the merging galaxies when the system collided. An additional possibility is that the tail has been a nursery of a few generations of young stellar systems which ultimately polluted this medium with metals, further enriching the already pre-enriched gas ejected to the tail when the galaxies collided.

CENTAURUS A: THE EXTRAGALACTIC SOURCE OF COSMIC RAYS WITH ENERGIES ABOVE THE KNEE

The origin of cosmic rays at all energies is still uncertain. In this paper, we present and explore an astrophysical scenario to produce cosmic rays with energy ranging from below 10(15) to 3 x 10(20) eV. We show here that just our Galaxy and the radio galaxy Cen A, each with their own galactic cosmic-ray particles but with those from the radio galaxy pushed up in energy by a relativistic shock in the jet emanating from the active black hole, are sufficient to describe the most recent data in the PeV to near ZeV energy range. Data are available over this entire energy range from the KASCADE, KASCADE-Grande, and Pierre Auger Observatory experiments. The energy spectrum calculated here correctly reproduces the measured spectrum beyond the knee and, contrary to widely held expectations, no other extragalactic source population is required to explain the data even at energies far below the general cutoff expected at 6 x 10(19) eV, the Greisen-Zatsepin-Kuz'min turnoff due to interaction with the cosmological microwave background. We present several predictions for the source population, the cosmic-ray composition, and the propagation to Earth which can be tested in the near future.