2,560 research outputs found
Energetic Quantum Limit in Large-Scale Interferometers
For each optical topology of an interferometric gravitational wave detector,
quantum mechanics dictates a minimum optical power (the ``energetic quantum
limit'') to achieve a given sensitivity. For standard topologies, when one
seeks to beat the standard quantum limit by a substantial factor, the energetic
quantum limit becomes impossibly large. Intracavity readout schemes may do so
with manageable optical powers.Comment: Revised version; to be published in Proceedings of the 1999 Edoardo
Amaldi Conference on Gravitational Waves; 11 pages including figures;
manuscript is RevTex; figures are .eps; an AIP style file is include
QND measurements for future gravitational-wave detectors
Second-generation interferometric gravitational-wave detectors will be
operating at the Standard Quantum Limit, a sensitivity limitation set by the
trade off between measurement accuracy and quantum back action, which is
governed by the Heisenberg Uncertainty Principle. We review several schemes
that allows the quantum noise of interferometers to surpass the Standard
Quantum Limit significantly over a broad frequency band. Such schemes may be an
important component of the design of third-generation detectors.Comment: 22 pages, 6 figures, 1 table; In version 2, more tutorial information
on quantum noise in GW interferometer and several new items into Reference
list were adde
Trade-off between quantum and thermal fluctuations in mirror coatings yields improved sensitivity of gravitational-wave interferometers
We propose a simple way to improve the laser gravitational-wave detectors
sensitivity by means of reduction of the number of reflective coating layers of
the core optics mirrors. This effects in the proportional decrease of the
coating thermal noise, the most notorious among the interferometers technical
noise sources. The price for this is the increased quantum noise, as well as
high requirements for the pump laser power and power at the beamsplitter.
However, as far as these processes depend differently on the coating thickness,
we demonstrate that a certain trade-off is possible, yielding a 20-30% gain
(for diverse gravitational wave signal types and interferometer
configurations), providing that feasible values of laser power and power on the
beamsplitter are assumed.Comment: 11 pages, 4 figures, 4 table
The effect of Maneb on implantation, fecundity rate and the thyroid activity in the rabbit
The fungicide Maneb is a member of the family of dithiocarbamates that is used in the control of the fungal diseases of plants. The purpose of this work is to examine the effect of Maneb on implantation and thyroid activity at doses of 5, 10 and 50 mg/kg/day by gavage for 10 days in the domestic female rabbit, Oryctolagus cuniculus. The rabbits were sacrificed on the 11th day of pregnancy. The results indicate an increase in the body weight in the treated female. An increase is also observed in the weightof liver in the treated females with a darker color. There is 50% of inhibition of implantation in the group treated with the higher dose (50 mg/kg/day) when compared with control rabbit. The inhibition of implantation by Maneb may be to due to hormonal imbalance
Complete Semantics to empower Touristic Service Providers
The tourism industry has a significant impact on the world's economy,
contributes 10.2% of the world's gross domestic product in 2016. It becomes a
very competitive industry, where having a strong online presence is an
essential aspect for business success. To achieve this goal, the proper usage
of latest Web technologies, particularly schema.org annotations is crucial. In
this paper, we present our effort to improve the online visibility of touristic
service providers in the region of Tyrol, Austria, by creating and deploying a
substantial amount of semantic annotations according to schema.org, a widely
used vocabulary for structured data on the Web. We started our work from
Tourismusverband (TVB) Mayrhofen-Hippach and all touristic service providers in
the Mayrhofen-Hippach region and applied the same approach to other TVBs and
regions, as well as other use cases. The rationale for doing this is
straightforward. Having schema.org annotations enables search engines to
understand the content better, and provide better results for end users, as
well as enables various intelligent applications to utilize them. As a direct
consequence, the region of Tyrol and its touristic service increase their
online visibility and decrease the dependency on intermediaries, i.e. Online
Travel Agency (OTA).Comment: 18 pages, 6 figure
Advanced quantum techniques for future gravitational-wave detectors
Quantum fluctuation of light limits the sensitivity of advanced laser interferometric gravitational-wave detectors. It is one of the principal obstacles on the way towards the next-generation gravitational-wave observatories. The envisioned significant improvement of the detector sensitivity requires using quantum non-demolition measurement and back-action evasion techniques, which allow us to circumvent the sensitivity limit imposed by the Heisenberg uncertainty principle. In our previous review article (Danilishin and Khalili in Living Rev Relativ 15:5, 2012), we laid down the basic principles of quantum measurement theory and provided the framework for analysing the quantum noise of interferometers. The scope of this paper is to review novel techniques for quantum noise suppression proposed in the recent years and put them in the same framework. Our delineation of interferometry schemes and topologies is intended as an aid in the process of selecting the design for the next-generation gravitational-wave observatories. © 2019, The Author(s)
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Recommendations for Implementing Hepatitis C Virus Care in Homeless Shelters: The Stakeholder Perspective.
Compared with the general population, homeless individuals are at higher risk of hepatitis C infection (HCV) and may face unique barriers in receipt of HCV care. This study sought the perspectives of key stakeholders toward establishing a universal HCV screening, testing, and treatment protocol for individuals accessing homeless shelters. Four focus groups were conducted with homeless shelter staff, practice providers, and social service outreach workers (n = 27) in San Francisco, California, and Minneapolis, Minnesota. Focus groups evaluated key societal, system, and individual-level facilitators and barriers to HCV testing and management. Interviews were transcribed and analyzed thematically. The societal-level barriers identified were lack of insurance, high-out-of-pocket expenses, restriction of access to HCV treatment due to active drug and/or alcohol use, and excessive paperwork required for HCV treatment authorization from payers. System-level barriers included workforce constraints and limited health care infrastructure, HCV stigma, low knowledge of HCV treatment, and existing shelter policies. At the individual level, client barriers included competing priorities, behavioral health concerns, and health attitudes. Facilitators at the system level for HCV care service integration in the shelter setting included high acceptability and buy in, and linkage with social service providers. Conclusion: Despite societal, system, and individual-level barriers identified with respect to the scale-up of HCV services in homeless shelters, there was broad support from key stakeholders for increasing capacity for the provision of HCV services in shelter settings. Recommendations for the scale-up of HCV services in homeless shelter settings are discussed
A new type of quantum speed meter interferometer: measuring speed to search for intermediate mass black holes
The recent discovery of gravitational waves (GW) by LIGO has impressively
launched the novel field of gravitational astronomy and it allowed us to
glimpse at exciting objects we could so far only speculate about. Further
sensitivity improvements at the low frequency end of the detection band of
future GW observatories rely on quantum non-demolition (QND) methods to
suppress fundamental quantum fluctuations of the light fields used to readout
the GW signal. Here we invent a novel concept of how to turn a conventional
Michelson interferometer into a QND speed meter interferometer with coherently
suppressed quantum back-action noise by using two orthogonal polarisations of
light and an optical circulator to couple them. We carry out a detailed
analysis of how imperfections and optical loss influence the achievable
sensitivity and find that the configuration proposed here would significantly
enhance the low frequency sensitivity and increase the observable event rate of
binary black hole coalescences in the range of by a factor
of up to .Comment: 8 pages, 5 figures. Modified figures and text in v
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