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We propose a method to overcome the usual limitation of current data processing techniques in optical and infrared long-baseline interferometry: most reduction pipelines assume uncorrelated statistical errors and ignore systematics. We use…

Instrumentation and Methods for Astrophysics · Physics 2019-01-23 Régis Lachaume , Markus Rabus , Andrés Jordán , Rafael Brahm , Tabetha Boyajian , Kaspar von Braun , Jean-Philippe Berger

We present new periodograms that are effective in distinguishing Doppler shift from spectral shape variability in astronomical spectra. These periodograms, building upon the concept of partial distance correlation, separate the periodic…

Instrumentation and Methods for Astrophysics · Physics 2022-04-06 Avraham Binnenfeld , Sahar Shahaf , Richard I. Anderson , Shay Zucker

Radio astronomical observations have very poor signal to noise ratios, unlike in other disciplines. On the other hand, it is possible to observe the object of interest for long time intervals as well as using a wider bandwidth.…

Astrophysics · Physics 2008-09-02 Sarod Yatawatta

The light curves observed from X-ray pulsars and magnetars reflect the radiation emission pattern, the geometry of the magnetic field, and the neutron star compactness. We study the statistics of X-ray pulse profiles in order to constrain…

High Energy Astrophysical Phenomena · Physics 2010-11-29 Marja Annala , Juri Poutanen

Timing techniques offer powerful tools to study dynamical astrophysical phenomena. In the X-ray band, they offer the potential of probing accretion physics down to the event horizon. Recent work has used frequency and energy-dependent time…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Abderahmen Zoghbi , Chris Reynolds , Ed Cackett

We report results from simultaneous radio and X-ray observations of PSR B0611+22 which is known to exhibit bursting in its single-pulse emission. The pulse phase of the bursts vary with radio frequency. The bursts are correlated in…

High Energy Astrophysical Phenomena · Physics 2016-08-31 Kaustubh Rajwade , Andrew Seymour , Duncan R Lorimer , Aris Karastergiou , Maciej Serylak , Maura A McLaughlin , Jean M Griessmeier

We compare the noise in interferometric measurements of the Vela pulsar from ground- and space-based antennas with theoretical predictions. The noise depends on both the flux density and the interferometric phase of the source. Because the…

Context. In asteroseismology the pulsation mode frequencies of a star are the fundamental data that are compared to theoretical predictions to determine a star's interior physics. Recent significant advances in the numerical, theoretical…

Solar and Stellar Astrophysics · Physics 2021-12-22 Dominic M. Bowman , Mathias Michielsen

We present the results obtained from a comprehensive timing and spectral study of two high-mass X-ray binary sources using NuSTAR observations. These two sources, IGR J16320-4751 and IGR J16479-4514, were discovered by INTEGRAL and have…

High Energy Astrophysical Phenomena · Physics 2023-06-05 Varun , Gayathri Raman

We present an analysis of quasar variability from data collected during a photometric monitoring of 50 objects carried out at CNPq/Laboratorio Nacional de Astrofisica, Brazil, between March 1993 and July 1996. A distinctive feature of this…

Astrophysics · Physics 2009-10-31 A. Garcia , L. Sodre , F. J. Jablonski , R. J. Terlevich

We consider a method for obtaining information on polarization of astronomical objects radiation at diffraction limited resolution - differential speckle polarimetry. As an observable we propose to use averaged cross spectrum of two…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Boris Safonov

Fluctuations of the soft X-ray background are investigated using harmonic analysis. A section of the ROSAT All-Sky Survey around the north galactic pole is used. The flux distribution is expanded into a set of harmonic functions and the…

Astrophysics · Physics 2009-11-07 W. Sliwa , A. M. Soltan , M. J. Freyberg

Conventional techniques that measure rapid time variations are inefficient or inadequate to discover and observe rapidly pulsating astronomical sources. It is therefore conceivable that there exist some classes of objects pulsating with…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Ermanno F Borra

Variations of the X-ray spectral slope have been found in many Active Galactic Nuclei (AGN) at moderate luminosities and redshifts, typically showing a "softer when brighter" behaviour. However, similar studies are not usually performed for…

Astrophysics of Galaxies · Physics 2017-06-28 Roberto Serafinelli , Fausto Vagnetti , Riccardo Middei

In many areas of astronomy, spectra of different objects are co-added or stacked to improve signal-to-noise and reveal population-level characteristics. As the number of exoplanets with measured transmission spectra grows, it becomes…

Earth and Planetary Astrophysics · Physics 2025-11-03 James Kirk , James E. Owen

Here we present a Bayesian method of including discrete measurements of dispersion measure due to the interstellar medium in the direction of a pulsar as prior information in the analysis of that pulsar. We use a simple simulation to show…

Instrumentation and Methods for Astrophysics · Physics 2013-12-10 Lindley Lentati , Paul Alexander , Michael P. Hobson

We propose a new test statistic based on a score process for determining the statistical significance of a putative signal that may be a small perturbation to a noisy experimental background. We derive the reference distribution for this…

Data Analysis, Statistics and Probability · Physics 2007-05-23 Ramani S. Pilla , Catherine Loader , Cyrus Taylor

We study statistical properties of stochastic variations in pulse arrival times, timing noise, in radio pulsars using a new analysis method applied in the time domain. The method proceeds in two steps. First, we subtract low-frequency…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Steve Price , Bennett Link , Steve Shore , David Nice

Power spectrum estimation is an important tool in many applications, such as the whitening of noise. The popular multitaper method enjoys significant success, but fails for short signals with few samples. We propose a statistical model…

Statistics Theory · Mathematics 2018-12-10 Joakim Andén , Amit Singer