3,918 research outputs found
Magnetic coupling to the Advanced Virgo payloads and its impact on the low frequency sensitivity
We study the electromagnetic coupling of the Advanced Virgo (AdV) Input
Mirror Payload (IMP) in response to a slowly time-varying magnetic field. As
the problem is not amenable to analytical solution, we employ and validate a
finite element (FE) analysis approach. The FE model is built to represent as
faithfully as possible the real object and it has been validated by comparison
with experimental measurements. The intent is to estimate the induced currents
and the magnetic field in the neighbourhood of the payload. The procedure found
21 equivalent electrical configurations that are compatible with the
measurements. These have been used to compute the magnetic noise contribution
to the total AdV strain noise. At the current stage of development AdV seems to
be unaffected by magnetic noise, but we foresee a non-negligible coupling once
AdV reaches the design sensitivity.Comment: 8 pages, 8 figures, 2 table
The Extreme Energy Events HECR array: status and perspectives
The Extreme Energy Events Project is a synchronous sparse array of 52
tracking detectors for studying High Energy Cosmic Rays (HECR) and Cosmic
Rays-related phenomena. The observatory is also meant to address Long Distance
Correlation (LDC) phenomena: the network is deployed over a broad area covering
10 degrees in latitude and 11 in longitude. An overview of a set of preliminary
results is given, extending from the study of local muon flux dependance on
solar activity to the investigation of the upward-going component of muon flux
traversing the EEE stations; from the search for anisotropies at the sub-TeV
scale to the hints for observations of km-scale Extensive Air Shower (EAS).Comment: XXV ECRS 2016 Proceedings - eConf C16-09-04.
Sensitivity Studies for Third-Generation Gravitational Wave Observatories
Advanced gravitational wave detectors, currently under construction, are
expected to directly observe gravitational wave signals of astrophysical
origin. The Einstein Telescope, a third-generation gravitational wave detector,
has been proposed in order to fully open up the emerging field of gravitational
wave astronomy. In this article we describe sensitivity models for the Einstein
Telescope and investigate potential limits imposed by fundamental noise
sources. A special focus is set on evaluating the frequency band below 10Hz
where a complex mixture of seismic, gravity gradient, suspension thermal and
radiation pressure noise dominates. We develop the most accurate sensitivity
model, referred to as ET-D, for a third-generation detector so far, including
the most relevant fundamental noise contributions.Comment: 13 pages, 7 picture
Measurement of the kinematic variables of beauty particles produced in 350 GeV/c -Cu interactions
Using a sample of b\=b events, produced in interactions in a copper target, which includes events where the decays of both and are well reconstructed, we measure the differential distributions with respect to and as well as some two-particle kinematic variables. We also compare our results with a previous experiment and with predictions based on perturbative QCD
Scientific Objectives of Einstein Telescope
The advanced interferometer network will herald a new era in observational
astronomy. There is a very strong science case to go beyond the advanced
detector network and build detectors that operate in a frequency range from 1
Hz-10 kHz, with sensitivity a factor ten better in amplitude. Such detectors
will be able to probe a range of topics in nuclear physics, astronomy,
cosmology and fundamental physics, providing insights into many unsolved
problems in these areas.Comment: 18 pages, 4 figures, Plenary talk given at Amaldi Meeting, July 201
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
Gravitational Waves From Known Pulsars: Results From The Initial Detector Era
We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom
Azimuthal correlation between beauty particles produced in 350 GeV/c -Cu interactions
Using a sample of triggered events, produced in interactions in a copper target, we have identified b\=b events. These include events where the decays of both and are well reconstructed. We measure the azimuthal \hbox{correlation} between beauty particles, and compare our result with predictions based on perturbative QCD
Sensitivity to Gravitational Waves from Compact Binary Coalescences Achieved during LIGO's Fifth and Virgo's First Science Run
We summarize the sensitivity achieved by the LIGO and Virgo gravitational
wave detectors for compact binary coalescence (CBC) searches during LIGO's
fifth science run and Virgo's first science run. We present noise spectral
density curves for each of the four detectors that operated during these
science runs which are representative of the typical performance achieved by
the detectors for CBC searches. These spectra are intended for release to the
public as a summary of detector performance for CBC searches during these
science runs.Comment: 12 pages, 5 figure
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