English
Related papers

Related papers: On time dilation in quasar light curves

200 papers

Longtime monitoring of gravitational lens systems is often done using telescopes and recording equipment with modest resolution. Still, it would be interesting to get as much information as possible from the measured lightcurves. From high…

Astrophysics · Physics 2015-06-24 A. Hirv , T. Eenmäe , T. Liimets , L. J. Liivamägi , J. Pelt

In this paper, we investigate the fully relativistic time delay of pulsar signals propagating in the vicinity of a rotating black hole and its potential mimickers, including a deformed Kerr black hole and the Janis-Newman-Winicour naked…

In order to investigate the dependence of quasar optical-UV variability on fundamental physical parameters like black hole mass, we have matched quasars from the QUEST1 variability survey with broad-lined objects from the SDSS. Black hole…

Astrophysics · Physics 2007-09-19 M. Wold , M. S. Brotherton , Z. Shang

The quadruple quasar H1413+117 (z_s = 2.56) has been monitored with the 2.0 m Liverpool Telescope in the r Sloan band from 2008 February to July. This optical follow-up leads to accurate light curves of the four quasar images (A-D), which…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Luis J. Goicoechea , Vyacheslav N. Shalyapin

A method for determining the time delays in gravitationally lensed quasars is proposed, which offers a simple and transparent procedure to mitigate the effects of microlensing. The method is based on fundamental properties of representation…

Instrumentation and Methods for Astrophysics · Physics 2018-02-09 V. S. Tsvetkova , V. M. Shulga , L. A. Berdina

A technique for timescale analysis of spectral lags performed directly in the time domain is developed. Simulation studies are made to compare the time domain technique with the Fourier frequency analysis for spectral time lags. The time…

Astrophysics · Physics 2014-10-13 T. P. Li , J. L. Qu , H. Feng , L. M. Song , G. Q. Ding , L. Chen

The phase of matter waves depends on proper time and is therefore susceptible to special-relativistic (kinematic) and gravitational (redshift) time dilation. Hence, it is conceivable that atom interferometers measure general-relativistic…

We present new light curves for the four bright images of the five image cluster-lensed quasar gravitational lens system SDSS~J1004+4112. The light curves span 14.5 yr and allow measurement of the time delay between the trailing bright…

Astrophysics of Galaxies · Physics 2022-09-28 J. A. Muñoz , C. S. Kochanek , J. Fohlmeister , J. Wambsganss , E. Falco , R. Forés-Toribio

The cosmic time dilation observed in Type Ia supernova light curves suggests that the passage of cosmic time varies throughout the evolution of the Universe. This observation implies that the rate of proper time is not constant, as assumed…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-25 Vaclav Vavrycuk

The dark matter halo has non-negligible effects on the gravitational lensing of supermassive black hole in the galaxy center. Our work presents a study on the time-delay of light in gravitational lensing of black holes enclosed by dark…

General Relativity and Quantum Cosmology · Physics 2024-10-14 Chen-Kai Qiao , Ping Su

Recent quasar microlensing observations have constrained the sizes of X-ray emission regions to be within about 10 gravitational radii of the central supermassive black hole. Therefore, the X-ray emission from lensed quasars is first…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Bin Chen , Xinyu Dai , Eddie Baron , Ronald Kantowski

We compile and analyse long term (~10 year) submillimetre (1.3, 0.87, 0.43 mm, submm) wavelength light curves of the Galactic centre black hole, Sagittarius A*. The 0.87 and 0.43 mm data are taken from the literature, while the majority of…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Jason Dexter , Brandon Kelly , Geoffrey C. Bower , Daniel P. Marrone , Jordan Stone , Richard Plambeck , Sheperd S. Doeleman

We test the robustness of published time delays for 11 lensed quasars by using two techniques to measure time shifts in their light curves. We chose to use two fundamentally different techniques to determine time delays in gravitationally…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-26 Eva Eulaers , Pierre Magain

We study the effect of light-bending on the signal of a pulsar in binaries with rotating black hole companions, focusing on stellar mass black holes. We show that the impacts of various parameters on the bending delays visually match with…

General Relativity and Quantum Cosmology · Physics 2025-06-09 Jyotijwal Debnath , Manjari Bagchi

It is shown that the energy dependence of the time lags in Cygnus X-1 excludes any significant contribution of the standard reflected component to the observed lags. The conclusion is valid in the 0.1--10 Hz frequency range where time lags…

Astrophysics · Physics 2009-11-06 O. Kotov , E. Churazov , M. Gilfanov

We study quasar proximity zones in a simulation that includes a self-consistent quasar formation model and realistic IGM environments. The quasar host halo is $10^{13}\ M_{\mathrm{\odot}}$ at $z=6$, more massive than typical halos studied…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-22 Yihao Zhou , Huanqing Chen , Tiziana Di Matteo , Yueying Ni , Rupert A. C. Croft , Simeon Bird

Strong gravitational lensing of time variable sources such as quasars and supernovae creates observable time delays between the multiple images. Time delays can provide a powerful cosmographic probe through the "time delay distance"…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-18 Alireza Hojjati , Alex G. Kim , Eric V. Linder

Gamma-Ray Bursts have been observed out to very high redshifts and provide time measures that are directly related to intrinsic time scales of the burst. Einstein's theory of relativity is quite definite that if the universe is expanding…

General Physics · Physics 2010-09-12 David F. Crawford

We have performed an optical observation campaign on PKS 2155-304, whose aim was to determine the variability properties of this object on very short time scales in several photometric bands. We detected variability on time scales as short…

Astrophysics · Physics 2007-05-23 S. Paltani , T. J. -L. Courvoisier , A. Blecha , P. Bratschi
‹ Prev 1 3 4 5 6 7 10 Next ›