Implementation of an F-statistic all-sky search for continuous gravitational waves in Virgo VSR1 data

We present an implementation of the F-statistic to carry out the first search in data from the Virgo laser interferometric gravitational wave detector for periodic gravitational waves from a priori unknown, isolated rotating neutron stars. We searched a frequency f(0) range from 100 Hz to 1 kHz and the frequency dependent spindown f(1) range from -1.6(f(0)/100 Hz) x 10(-9) Hz s(-1) to zero. A large part of this frequency-spindown space was unexplored by any of the all-sky searches published so far. Our method consisted of a coherent search over two-day periods using the F-statistic, followed by a search for coincidences among the candidates from the two-day segments. We have introduced a number of novel techniques and algorithms that allow the use of the fast Fourier transform (FFT) algorithm in the coherent part of the search resulting in a fifty-fold speed-up in computation of the F-statistic with respect to the algorithm used in the other pipelines. No significant gravitational wave signal was found. The sensitivity of the search was estimated by injecting signals into the data. In the most sensitive parts of the detector band more than 90% of signals would have been detected with dimensionless gravitational-wave amplitude greater than 5 x 10(-24).

Alignment of the CMS tracker with LHC and cosmic ray data

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Description and performance of track and primary-vertex reconstruction with the CMS tracker

A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For t (t) over bar events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p(T) > 0.9GeV is 94% for pseudorapidities of vertical bar eta vertical bar < 0.9 and 85% for 0.9 < vertical bar eta vertical bar < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p(T) = 100GeV emitted at vertical bar eta vertical bar < 1.4, the resolutions are approximately 2.8% in p(T), and respectively, 10 m m and 30 mu m in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10-12 mu m in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

Search for gravitational radiation from intermediate mass black hole binaries in data from the second LIGO-Virgo joint science run

This paper reports on an unmodeled, all-sky search for gravitational waves from merging intermediate mass black hole binaries (IMBHB). The search was performed on data from the second joint science run of the LIGO and Virgo detectors (July 2009-October 2010) and was sensitive to IMBHBs with a range up to similar to 200 Mpc, averaged over the possible sky positions and inclinations of the binaries with respect to the line of sight. No significant candidate was found. Upper limits on the coalescence-rate density of nonspinning IMBHBs with total masses between 100 and 450 M-circle dot and mass ratios between 0.25 and 1 were placed by combining this analysis with an analogous search performed on data from the first LIGO-Virgo joint science run (November 2005-October 2007). The most stringent limit was set for systems consisting of two 88 M-circle dot black holes and is equal to 0.12 Mpc(-3) Myr(-1) at the 90% confidence level. This paper also presents the first estimate, for the case of an unmodeled analysis, of the impact on the search range of IMBHB spin configurations: the visible volume for IMBHBs with nonspinning components is roughly doubled for a population of IMBHBs with spins aligned with the binary's orbital angular momentum and uniformly distributed in the dimensionless spin parameter up to 0.8, whereas an analogous population with antialigned spins decreases the visible volume by similar to 20%.

First all-sky search for continuous gravitational waves from unknown sources in binary systems

We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to similar to 2,254 h and a frequency-and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of projected semimajor axes of the orbit from similar to 0.6 x 10(-3) ls to similar to 6,500 ls assuming the orbit of the binary is circular. While no plausible candidate gravitational wave events survive the pipeline, upper limits are set on the analyzed data. The most sensitive 95% confidence upper limit obtained on gravitational wave strain is 2.3 x 10(-24) at 217 Hz, assuming the source waves are circularly polarized. Although this search has been optimized for circular binary orbits, the upper limits obtained remain valid for orbital eccentricities as large as 0.9. In addition, upper limits are placed on continuous gravitational wave emission from the low-mass x-ray binary Scorpius X-1 between 20 Hz and 57.25 Hz.

Multimessenger search for sources of gravitational waves and high-energy neutrinos: Initial results for LIGO-Virgo and IceCube

We report the results of a multimessenger search for coincident signals from the LIGO and Virgo gravitational-wave observatories and the partially completed IceCube high-energy neutrino detector, including periods of joint operation between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010 run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79 strings. We find no significant coincident events, and use the search results to derive upper limits on the rate of joint sources for a range of source emission parameters. For the optimistic assumption of gravitational-wave emission energy of 10(-2) M(circle dot)c(2) at similar to 150 Hz with similar to 60 ms duration, and high-energy neutrino emission of 1051 erg comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the source rate below 1.6 x 10(-2) Mpc(-3) yr(-1). We also examine how combining information from gravitational waves and neutrinos will aid discovery in the advanced gravitational-wave detector era.

Improved Upper Limits on the Stochastic Gravitational-Wave Background from 2009-2010 LIGO and Virgo Data

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Omega(GW)(f) = Omega(alpha)(f/f(ref))(alpha), we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of alpha = 0, we constrain the energy density of the stochastic background to be Omega(GW)(f) < 5.6 x 10(-6). For the 600-1000 Hz band, Omega(GW)(f) < 0.14(f/900 Hz)(3), a factor of 2.5 lower than the best previously reported upper limits. We find Omega(GW)(f) < 1.8 x 10(-4) using a spectral index of zero for 170-600 Hz and Omega(GW)(f) < 1.0(f/1300 Hz)(3) for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

A imagem poética na poesia concreta de Augusto de Campos

A presente monografia tem a finalidade de refletir como a imagem poética é construída na poesia concreta de Augusto de Campos. Para isso, será utilizada a teoria de alguns estudiosos, como Alfredo Bosi, Octavio Paz, Philadelpho Menezes, Aguillar, entre outros, para embasar a reflexão sobre a imagem poética que se desenha a partir da leitura da poesia por meio das palavras que compõem a produção artística. Há uma ênfase, durante a análise das poesias, nas palavras que as constituem, pois elas formam um elemento fundamental para a criação da imagem poética na produção da poesia concretista. O trabalho também reflete sobre a repercussão do movimento Concretista em décadas distintas (50,70 e 90) e em diferentes vertentes, como na música, nos âmbitos nacional e internacional, ressaltando a importância do Concretista para o enriquecimento da poesia, especialmente as compostas por Augusto de Campos. Também será mencionada a diferença entre a poesia visual e a poesia concreta. Para isso, serão explicitadas as suas peculiaridades e as suas propostas

Personagens e espaço em romances de Aluísio Azevedo

The characters of O mulato, Casa de pensão and O cortiço, well written books by the writer Aluísio Azevedo, may be considered predominantly flat, for they were built with a single or few features. This kind of character can be even defined by the type, which represents certain dominant features (professional, psychological, cultural, economic, religious, etc.) from the diegetic universe in which the action takes place. This character subcategory is present in certain artistic periods such as Realism and Naturalism, and can be understood as the main character between the individual and the collective, between the concrete and the abstract. Yet, the social space, in the novels of the above mentioned literary movements configures itself, especially in terms of the presence and types of extras: it is about describing environments that illustrate, almost always, in a historical period context of critical intent, vices and deformations of the society, as we can see depicted in the three novels of the author. In turn, the narrative categories that most decisively influence the space representation are the instance (the narrator) and the narrative perspective (focusing). In the case of O mulato, Casa de pensão and O cortiço, the dominance is in choosing the omniscient narrator, who prefers a panoramic view, limited to an exterior and strictly objective description. The survey was developed through readings, literary cataloging and corpus discussions, with a theoretical basis determined by three dimensions: a) critical essays about the author and his works, such as those by Jean-Yves Mérian, Aluísio Azevedo, vida e obra: (1857-1913) and parts of the literature histories which deal with Naturalism, such as those by Alfredo Bosi, História concisa da literatura brasileira, b) theoretical studies about the novel character, such as those by Antonio Candido, A personagem do romance, and the romantic space ...

Mito, história e memória em Órfãos do Eldorado de Milton Hatoum

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Os labirintos da memória em Orfãos do Eldorado de Milton Hatoum

This article aims to analyze aspects of Orfãos do Eldorado (2008), by Milton Hatoum, to elucidate the plot construction by the use of memory, which articulates three narrative perspectives: the mythic, the social-historic and the mythic-social-personal. This process presents as a result a textual configuration marked by a contemporary diction, by the creative work and by a certain lyricism that allows us to say, as Tania Pellegrini and Alfredo Bosi, that there is a ‘revisitated’ regionalism in this author work.

São Bernardo: construção do romance pela memória

This paper concentrates on demonstrating that the novel called São Bernardo ,written by Graciliano Ramos, utilizes some literary strategies that cause the effect of being built by rememorizations, which is a vital aspect of several of the author’s titles. Such objective is reached via the analyses of how the following narrative categories: focalization, narrator, characters, story and time converge toward the elaboration of the memory and the comparison between this construction on São Bernardo and Angústia. In order to be successful on this task, three groups of study constitute our theoretical basis: a) critical essays concerning Graciliano Ramos; b) theoretical propositions about the narrative categories; c) academic articles on the constitution of memory. Papers composed by Antonio Candido, Alfredo Bosi, Sonia Brayner, Luís Costa Lima and others are part of the first group. The second one is constituted by propositions of Gérard Genette, Benedito Nunes etc. Finally, on the last one, we find Paul Ricouer and Henri Bergson

As memórias de crónica de una muerte anunciada

Pós-graduação em Estudos Literários - FCLAR

O poema em música e a música além do poema: estudo sobre a relação entre música e poesia em obras de Almeida Prado, Eduardo Guimarães Álvares e Harry Crowl

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)