We address the problem of noise regression in the output of gravitational-wave (GW) interferometers, using data from the physical environmental monitors (PEM). The objective of the regression ...analysis is to predict environmental noise in the GW channel from the PEM measurements. One of the most promising regression methods is based on the construction of Wiener-Kolmogorov (WK) filters. Using this method, the seismic noise cancellation from the LIGO GW channel has already been performed. In the presented approach the WK method has been extended, incorporating banks of Wiener filters in the time-frequency domain, multi-channel analysis and regulation schemes, which greatly enhance the versatility of the regression analysis. Also we present the first results on regression of the bi-coherent noise in the LIGO data.
Prospects for using metal hydride power sources are discussed, and experimental material on improving their performance is summarized. Achievements in the modification of electrode materials and ...electrolytes are surveyed. Using the example of the work of the Complex of Laboratories for Hydrogen Materials Science at the Federal Research Center for Chemical Physics and Medicinal Chemistry, Russian Academy of Sciences (FRC PCP&MC RAS), the prospects for using composite materials to create next-generation metal hydride power sources are shown.
The meat of fin-footed mammals contains complete protein with high biological value, as well as vitamins and minerals that are so necessary for the vital functions of the human body in the Far North. ...Nowadays fin-footed mammals are hunted only to provide food for indigenous people. In accordance with this, it was found that the procedure of the determination of the quality and safety of products obtained from marine mammals is outdated and requires changes. It is necessary to include in the regulatory and technical framework (GOST, SanPin) this type of meat and by-products of marine mammals, since this type of product is specific and the norms suitable for meat of all other slaughtered animals do not quite fit this category of meat because they do not contain indicators characterizing the quality and first of all, the safety of this type of product. The article considers the organization of the development of quota allocations for the fishing of marine mammals in the Chukotka Autonomous Region and the organization of veterinary and sanitary inspection of the products of slaughter of commercial animals.
We estimated the sensitivity of the upcoming advanced ground-based gravitational-wave observatories (the LIGO, Virgo, and KAGRA interferometers) to coalescing intermediate mass black hole binaries ...(IMBHB). We added waveforms modeling the gravitational radiation emitted by IMBHBs to simulated data from detectors and searched for the injected signals with the coherent WaveBurst algorithm. The tested parameter space of the binaries covers nonspinning IMBHBs with source-frame total masses between 50 and 1050M sub(odot) and mass ratios between and 1/6 and 1. We found that advanced detectors could be sensitive to these systems up to a range of a few Gpc. A theoretical model was adopted to estimate the expected observation rates, yielding up to a few tens of events per year. Thus, our results indicate that advanced detectors will have a reasonable chance to collect the first direct evidence for intermediate mass black holes and to open a new, intriguing channel for probing the Universe over cosmological scales.
Compact binary coalescence (CBC) is one of the most promising sources of gravitational waves. These sources are usually searched for with matched filters which require accurate calculation of the GW ...waveforms and generation of large template banks. We present a complementary search technique based on algorithms used in un-modeled searches. Initially designed for detection of un-modeled bursts, which can span a very large set of waveform morphologies, the search algorithm presented here is constrained for targeted detection of the smaller subset of CBC signals. The constraint is based on the assumption of elliptical polarization for signals received at the detector. We expect that the algorithm is sensitive to CBC signals in a wide range of masses, mass ratios and spin parameters. In preparation for the analysis of data from the fifth LIGO-Virgo science run (S5), we performed preliminary studies of the algorithm on test data. We present the sensitivity of the search to different types of simulated binary black hole waveforms. Also, we discuss how to extend the results of the test run into a search over all of the current LIGO-Virgo data set.
Presented in this paper is a detailed and direct comparison of the LIGO and Virgo binary neutron star detection pipelines. In order to test the search programs, numerous inspiral signals were added ...to 24 hours of simulated detector data. The efficiencies of the different pipelines were tested, and found to be comparable. Parameter estimation routines were also tested. We demonstrate that there are definite benefits to be had if LIGO and Virgo conduct a joint coincident analysis; these advantages include increased detection efficiency and the providing of source sky location information.
The search procedure for burst gravitational waves has been studied using 24 hours of simulated data in a network of three interferometers (Hanford 4-km, Livingston 4-km and Virgo 3-km are the ...example interferometers). Several methods to detect burst events developed in the LIGO Scientific Collaboration (LSC) and Virgo collaboration have been studied and compared. We have performed coincidence analysis of the triggers obtained in the different interferometers with and without simulated signals added to the data. The benefits of having multiple interferometers of similar sensitivity are demonstrated by comparing the detection performance of the joint coincidence analysis with LSC and Virgo only burst searches. Adding Virgo to the LIGO detector network can increase by 50% the detection efficiency for this search. Another advantage of a joint LIGO-Virgo network is the ability to reconstruct the source sky position. The reconstruction accuracy depends on the timing measurement accuracy of the events in each interferometer, and is displayed in this paper with a fixed source position example.
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