scholarly journals Constraints on cosmic curvature with lensing time delays and gravitational waves

2019 ◽  
Vol 99 (8) ◽  
Author(s):  
Kai Liao
Keyword(s):  
Gravitational Waves ◽  
Time Delays

scholarly journals Gravitational lens time delays and gravitational waves

1994 ◽  
Vol 50 (8) ◽  
pp. 4895-4902 ◽  
Author(s):  
Joshua A. Frieman ◽  
Diego D. Harari ◽  
Gabriela C. Surpi
Keyword(s):  
Gravitational Waves ◽  
Time Delays ◽  
Gravitational Lens

scholarly journals Observational signatures of microlensing in gravitational waves at LIGO/Virgo frequencies

2019 ◽  
Vol 627 ◽  
pp. A130 ◽  
Author(s):  
J. M. Diego ◽  
O. A. Hannuksela ◽  
P. L. Kelly ◽  
G. Pagano ◽  
T. Broadhurst ◽  
...  
Keyword(s):  
Gravitational Waves ◽  
Gravitational Lensing ◽  
Time Delays ◽  
Saddle Points ◽  
Negative Parity ◽  
Interference Effects ◽  
Critical Curves ◽  
Magnification Factors ◽  
Interference Distortions ◽  
Stellar Masses

Microlenses with typical stellar masses (a few M⊙) have traditionally been disregarded as potential sources of gravitational lensing effects at LIGO/Virgo frequencies, since the time delays are often much smaller than the inverse of the frequencies probed by LIGO/Virgo, resulting in negligible interference effects at LIGO/Virgo frequencies. While this is true for isolated microlenses in this mass regime, we show how, under certain circumstances and for realistic scenarios, a population of microlenses (for instance stars and remnants from a galaxy halo or from the intracluster medium) embedded in a macromodel potential (galaxy or cluster) can conspire together to produce time delays of order one millisecond, which would produce significant interference distortions in the observed strains. At sufficiently large magnification factors (of several hundred), microlensing effects should be common in gravitationally lensed gravitational waves. We explored the regime where the predicted signal falls in the frequency range probed by LIGO/Virgo. We find that stellar mass microlenses, permeating the lens plane, and near critical curves, can introduce interference distortions in strongly lensed gravitational waves. Lensed events with negative parity, or saddle points (which have never before been studied in the context of gravitational waves), and that take place near caustics of macromodels, are more likely to produce measurable interference effects at LIGO/Virgo frequencies. This is the first study that explores the effect of a realistic population of microlenses, including a macromodel, on strongly lensed gravitational waves.

scholarly journals Anomalies in Time Delays of Lensed Gravitational Waves and Dark Matter Substructures

2018 ◽  
Vol 867 (1) ◽  
pp. 69 ◽  
Author(s):  
Kai Liao ◽  
Xuheng Ding ◽  
Marek Biesiada ◽  
Xi-Long Fan ◽  
Zong-Hong Zhu
Keyword(s):  
Dark Matter ◽  
Gravitational Waves ◽  
Time Delays

scholarly journals LENSINGGW: a PYTHON package for lensing of gravitational waves

2020 ◽  
Vol 643 ◽  
pp. A167
Author(s):  
G. Pagano ◽  
O. A. Hannuksela ◽  
T. G. F. Li
Keyword(s):  
Gravitational Wave ◽  
Gravitational Waves ◽  
Time Delays ◽  
Arrival Time ◽  
Working Mechanism ◽  
Compact Binaries ◽  
Strong Lensing ◽  
Typical Time ◽  
Compact Sources ◽  
Python Package

Advanced LIGO and Advanced Virgo might be able to observe the first lensed gravitational waves in the coming years. With the addition of the KAGRA and LIGO India detectors to the detector network and with the future construction of the Einstein Telescope we might be able to observe hundreds of lensed events. Ground-based gravitational-wave detectors can resolve arrival-time differences on the order of the inverse of the observed frequencies. The LIGO and Virgo frequency band spans from a few Hz to a few kHz, therefore the typical time resolution of current interferometers is on the order of milliseconds. When microlenses are embedded in galaxies or galaxy clusters, lensing can become more prominent and result in observable time delays at LIGO and Virgo frequencies. Therefore, gravitational waves might offer an exciting alternative probe of microlensing. However, only a few lensing configurations have currently been worked out in the context of gravitational-wave lensing. In this paper, we present LENSINGGW, a PYTHON package designed to handle both strong lensing and microlensing of compact binaries and the related gravitational-wave signals in the geometrical optics limit. This synergy paves the way for systematic parameter space investigations and for the detection of arbitrary lens configurations and compact sources. Here we focus on the LIGO and Virgo frequencies. We demonstrate the working mechanism of LENSINGGW and its use in studying microlenses that are embedded in galaxies.

The Search for Gravitational Waves

2008 ◽  
Vol 30 ◽  
pp. 15-25
Author(s):  
A.M. Sintes
Keyword(s):  
Gravitational Waves

Penjadwalan Mesin dengan Metode Integer Linear Programming pada PT. XYZ

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Fransiskus Lauson Matondang ◽  
Rosnani Ginting
Keyword(s):  
Integer Programming ◽  
Time Delays ◽  
Parallel Machines ◽  
Research Concept ◽  
Total Settlement ◽  
Approach Method ◽  
Additional Costs ◽  
Maximum Completion Time ◽  
Completion Times ◽  
Better Than

PT XYZ sering mengalami keterlambatan waktu karena dalam setiap keterlambatan yang dilakukan selalu ada penalty yang diberikan kepada perusahaan dan hal ini mengakibatkan tambahan biaya , oleh karena itu hal ini harus dihindari dengan membuat penjadwalan yang efisien, dalam hal ini dilakukanlah perbaikan dengan meminimisasi waktu penyelesaian maksimum Cmax pada mesin paralel yang berpola aliran flowshop (dan tidak boleh dilakukan interupsi yang dilakukan pada pekerjaan yang sedang diproses, untuk melakukan pekerjaan lainnya, satu lintasan hanya memproduksi satu produk dan hanya satu produk juga yang dikerjakan secara langsung. Waktu penyelesaian yang berbeda dari setiap mesin dengan pengerjaannya juga adalah masalah yang dihadapi untuk menjadikan mesin mesin ini sesuai menjadi satu penjadwalan yang terintegrasi dengan metode integer programming yang membuat penjadwalan dengan konsep riset operasi dengan metode pendekatan 0-1 utuk menjadi lebih efisien lagi , dihasilkan minimisasi keterlambatan total penyelesaian order dengan 42,28 menit lebih baik dari sebelumnya.   PT XYZ often experiences time delays because in every delay made there is always a penalty given to the company and this results in additional costs, therefore this must be avoided by making efficient scheduling, in this case repairs are carried out by minimizing the maximum completion time of Cmax on parallel machines that are patterned with flowshop flow (and no interruptions should be carried out on the work being processed, to do other work, one track only produces one product and only one product is directly worked. Different completion times of each machine with the workmanship is also the problem faced to make this machine suitable to be one scheduling integrated with integer programming methods that makes scheduling with the operational research concept with the 0-1 approach method to be more efficient, resulting in minimization of the delay in the total settlement of orders with 42.28 minutes was better than before.

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