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Related papers: A Wavelet Exploration of the Q0957+561 A,B brightn…

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From optical R band data of the double quasar QSO 0957+561A,B, we made two new difference light curves (about 330 days of overlap between the time-shifted light curve for the A image and the magnitude-shifted light curve for the B image).…

We have continued our effort to re-reduce archival Q0957+561 brightness monitoring data and present results for 1629 R-band images using the methods for galaxy subtraction and seeing correction reported previously. The new dataset comes…

Astrophysics · Physics 2009-10-31 Wesley N. Colley , Rudolph E. Schild

Wavelet analysis, in addition to power density spectra, is another method to study the quasi-periodic signals in the light curves, but has been rarely used in black hole X-ray transients. We performed wavelet analysis of X-ray timing…

High Energy Astrophysical Phenomena · Physics 2024-02-20 X. Chen , W. Wang

We re-analyze brightness data sampled intensively over 5 nights at two epochs separated by the quasar lens time delay, to examine the nature of the observed microlensing. We find strong evidence for a microlensing event with an amplitude of…

Astrophysics · Physics 2009-11-07 Wesley N. Colley , Rudolph E. Schild

We present a detailed structure function analysis of the UV variability of Q0957+561. From new optical observations, we constructed normalized structure functions of the quasar luminosity at restframe wavelengths of 2100 and 2600 \AA. Old…

Astrophysics · Physics 2009-11-13 L. J. Goicoechea , V. N. Shalyapin , R. Gil-Merino , A. Ullán

We report an increase of more than 0.2 mag in the optical brightness of the leading image (A) of the gravitational lens Q0957+561, detected during the 09/2000 -- 06/2001 monitoring campaign (2001 observing season). The brightening is…

Astrophysics · Physics 2009-11-07 A. Oscoz , D. Alcalde , M. Serra-Ricart , E. Mediavilla , J. A. Munoz

We report on 15 years of VLA monitoring of the gravitational lens B0957+561 at 6 cm. Since our last report in 1992, there have been 32 additional observations, in which both images have returned to their quiescent flux density levels and…

Astrophysics · Physics 2009-10-28 Deborah B. Haarsma , Jacqueline N. Hewitt , Joseph Lehár , Bernard F. Burke

In quantum computing, characterizing the full noise profile of qubits can aid in increasing coherence times and fidelities by developing error-mitigating techniques specific to the noise present. This characterization also supports efforts…

We study the scaling behavior of the fluctuations, as extracted through wavelet coefficients based on discrete wavelets. The analysis is carried out on a variety of physical data sets, as well as Gaussian white noise and binomial…

Data Analysis, Statistics and Probability · Physics 2008-04-16 P. Manimaran , Prasanta K. Panigrahi , Jitendra C. Parikh

Wavelet basis functions are a natural tool for analyzing turbulent flows containing localized coherent structures of different spatial scales. Here, wavelets are used to study the onset and subsequent transition to fully developed…

Plasma Physics · Physics 2022-04-13 Ari Le , Vadim Roytershteyn , Homa Karimabadi , Adam Stanier , Luis Chacon , Kai Schneider

The long-term variability of a sample of 486 optically selected QSOs in the fields of the SA94, SA57 and SGP has been studied. The relations of variability with luminosity and redshift have been investigated by means of statistical…

Astrophysics · Physics 2007-05-23 S. Cristiani , S. Trentini , F. La Franca , I. Aretxaga , P. Andreani , R. Vio , A. Gemmo

Studies of the lensed quasar ${\rm Q}0957+561 {\rm A,B}$ have shown evidence for microlensing in the brightness history of the quasar images. It had been suggested that a frequency offset between the brightness fluctuations in each of the…

Astrophysics · Physics 2007-05-23 Shane L. Larson , Rudolph Schild

We present the first results from a pilot programme to monitor the short term optical variability in Broad Absorption Line system QSOs. Intra-night optical variations of ~5% were detected on time scales of ~ one hour in QSOs 0846+156 and…

Astrophysics · Physics 2009-10-30 G. C. Anupama , Arati Chokshi

The nature of the magnetic field fluctuations in the solar wind between the ion and electron scales is still under debate. Using the Cluster/STAFF instrument, we make a survey of the power spectral density and of the polarization of these…

The influence of higher-order wavelet properties on the analytic wavelet transform behavior is investigated, and wavelet functions offering advantageous performance are identified. This is accomplished through detailed investigation of the…

Methodology · Statistics 2011-10-18 J. M. Lilly , S. C. Olhede

The analysis of gravitational-wave (GW) signals is one of the most challenging application areas of signal processing. Wavelet transforms are specially helpful in detecting and analyzing GW transients and several analysis pipelines are…

General Relativity and Quantum Cosmology · Physics 2024-05-27 Andrea Virtuoso , Edoardo Milotti

We extend the gr-band time coverage of the gravitationally lensed double quasar Q0957+561. New gr light curves permit us to detect significant intrinsic fluctuations, to determine new time delays, and thus to gain perspective on the…

Astrophysics · Physics 2009-11-13 V. N. Shalyapin , L. J. Goicoechea , E. Koptelova , A. Ullan , R. Gil-Merino

This work brings a wavelet analysis for 14 Kepler white dwarf stars, in order to confirm their photometric variability behavior and to search for periodicities in these targets. From the observed Kepler light curves we obtained the wavelet…

Solar and Stellar Astrophysics · Physics 2019-01-17 S. R. de Lira , J. P. Bravo , I. C. Leao , A. D. da Costa , B. L. Canto Martins , D. B. de Freitas , J. R. De Medeiros

Since the persuasive determination of the time-delay in Q0957+561, much interest has centered around shifting and subtracting the A and B light-curves to look for residuals due to microlensing. Solar mass objects in the lens galaxy produce…

Astrophysics · Physics 2009-10-30 Wesley N. Colley , Rudolph E. Schild
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