All-sky search for short gravitational-wave bursts in the second Advanced LIGO and Advanced Virgo run

We present the results of a search for short-duration gravitational-wave transients in the data from the second observing run of Advanced LIGO and Advanced Virgo. We search for gravitational-wave transients with a duration of milliseconds to approximately one second in the 32-4096 Hz frequency band with minimal assumptions about the signal properties, thus targeting a wide variety of sources. We also perform a matched-filter search for gravitational-wave transients from cosmic string cusps for which the waveform is well modeled. The unmodeled search detected gravitational waves from several binary black hole mergers which have been identified by previous analyses. No other significant events have been found by either the unmodeled search or the cosmic string search. We thus present the search sensitivities for a variety of signal waveforms and report upper limits on the source rate density as a function of the characteristic frequency of the signal. These upper limits are a factor of 3 lower than the first observing run, with a 50% detection probability for gravitational-wave emissions with energies of ∼10-9 Mc2 at 153 Hz. For the search dedicated to cosmic string cusps we consider several loop distribution models, and present updated constraints from the same search done in the first observing run

Search for Eccentric Binary Black Hole Mergers with Advanced LIGO and Advanced Virgo during Their First and Second Observing Runs

When formed through dynamical interactions, stellar-mass binary black holes (BBHs) may retain eccentric orbits (e > 0.1 at 10 Hz) detectable by ground-based gravitational-wave detectors. Eccentricity can therefore be used to differentiate dynamically formed binaries from isolated BBH mergers. Current template-based gravitational-wave searches do not use waveform models associated with eccentric orbits, rendering the search less efficient for eccentric binary systems. Here we present the results of a search for BBH mergers that inspiral in eccentric orbits using data from the first and second observing runs (O1 and O2) of Advanced LIGO and Advanced Virgo. We carried out the search with the coherent WaveBurst algorithm, which uses minimal assumptions on the signal morphology and does not rely on binary waveform templates. We show that it is sensitive to binary mergers with a detection range that is weakly dependent on eccentricity for all bound systems. Our search did not identify any new binary merger candidates. We interpret these results in light of eccentric binary formation models. We rule out formation channels with rates ⪆100 Gpc-3 yr-1 for e > 0.1, assuming a black hole mass spectrum with a power-law index ≲2

Search for intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network

Gravitational-wave astronomy has been firmly established with the detection of gravitational waves from the merger of ten stellar-mass binary black holes and a neutron star binary. This paper reports on the all-sky search for gravitational waves from intermediate mass black hole binaries in the first and second observing runs of the Advanced LIGO and Virgo network. The search uses three independent algorithms: two based on matched filtering of the data with waveform templates of gravitational-wave signals from compact binaries, and a third, model-independent algorithm that employs no signal model for the incoming signal. No intermediate mass black hole binary event is detected in this search. Consequently, we place upper limits on the merger rate density for a family of intermediate mass black hole binaries. In particular, we choose sources with total masses M=m1+m2ϵ[120,800] M and mass ratios q=m2/m1ϵ[0.1,1.0]. For the first time, this calculation is done using numerical relativity waveforms (which include higher modes) as models of the real emitted signal. We place a most stringent upper limit of 0.20 Gpc-3 yr-1 (in comoving units at the 90% confidence level) for equal-mass binaries with individual masses m1,2=100 M and dimensionless spins χ1,2=0.8 aligned with the orbital angular momentum of the binary. This improves by a factor of ∼5 that reported after Advanced LIGO's first observing run

Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

We present results from a semicoherent search for continuous gravitational waves from the low-mass X-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the $\mathcal{J}$-statistic, and by analysing data from Advanced LIGO's second observing run. In the frequency range searched, from $60$ to $650\,\mathrm{Hz}$, we find no evidence of gravitational radiation. At $194.6\,\mathrm{Hz}$, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95\% confidence) of $h_0^{95\%} = 3.47 \times 10^{-25}$ when marginalising over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering

RD-NEA: Prototipo de Repositorio Digital del Nordeste : Una contribución a la articulación de las universidades con el nivel medio del sistema educativo regional

En este trabajo se presenta un proyecto interinstitucional orientado a contribuir al proceso de articulación de las universidades y el nivel medio mediante el desarrollo de un prototipo de repositorio digital de acceso abierto que permitirá la difusión, distribución y acceso a la producción científica, académica y de materiales educativos de las universidades y otros ámbitos del sistema educativo de la región del Nordeste del país (NEA), enfocadas en este propósito. Asimismo, se elaborará una conceptualización acerca del paradigma del acceso abierto como basamento para proponer políticas institucionales vinculadas con la implementación de RD-NEA en las universidades involucradas. Para alcanzar estos objetivos se propone el abordaje del tema desde una fuerte perspectiva tecnológica con la intervención de otras disciplinas de los investigadores que conforman el equipo, a fin de plasmar en el prototipo una oferta conjunta enriquecedora para sus destinatarios. La realización del proyecto aportará en la generación de un repositorio digital de recursos educativos que sean aplicables en el nivel medio y superior no universitario de la región con miras a aportar una estrategia adicional en pro de afianzar la articulación con el nivel de Educación Superior.Sociedad Argentina de Informática e Investigación Operativ

Vinculación de universidades del NEA orientada a la generación de un repositorio digital como aporte a la articulación entre instituciones del nivel medio y superior

Se describe un proyecto interinstitucional elaborado mediante el trabajo cooperativo de cuatro universidades nacionales del NEA, mediante el cual se propone diseñar y desarrollar un prototipo de repositorio digital de acceso abierto. Su implementación en esta región del país contribuirá al proceso de articulación de las universidades y el nivel medio permitiendo la difusión, distribución y acceso a la producción científica, académica y de materiales educativos. Asimismo, se elaborará una conceptualización acerca del paradigma del acceso abierto como basamento para proponer políticas institucionales vinculadas con la implementación de RD-NEA en las universidades involucradas. Para alcanzar estos objetivos se propone el abordaje del tema desde una fuerte perspectiva tecnológica con la intervención de otras disciplinas como las ciencias de la información y de la educación.Eje: Tecnología Informática aplicada en educaciónRed de Universidades con Carreras en Informática (RedUNCI