Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission

Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission PDF Author: Daniel V. Engovatov
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 126

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Book Description
Much work has been done on trying to gain insight into the dynamics of accreting systems, such as black hole and neutron star binaries, by analyzing timing measurements from X-ray telescopes. In this thesis we present a novel approach to this problem using a kurtosis measure of the wavelet distribution obtained from the light curve to quantify the presence of intermittent activity. This method is applied to large RXTE data sets for GRS 1915+105, and Cygnus X-1. We demonstrate a new approach to reveal bursting modes. Negative correlation between the presence of a low frequency QPO in the Cygnus X-1 Fourier power spectrum and a wavelet kurtosis indicator of temporal intermittency is observed. A possible interpretation of this anti-correlation is developed using a "dripping handrail" transient chaos model.

Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission

Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission PDF Author: Daniel V. Engovatov
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 126

Get Book Here

Book Description
Much work has been done on trying to gain insight into the dynamics of accreting systems, such as black hole and neutron star binaries, by analyzing timing measurements from X-ray telescopes. In this thesis we present a novel approach to this problem using a kurtosis measure of the wavelet distribution obtained from the light curve to quantify the presence of intermittent activity. This method is applied to large RXTE data sets for GRS 1915+105, and Cygnus X-1. We demonstrate a new approach to reveal bursting modes. Negative correlation between the presence of a low frequency QPO in the Cygnus X-1 Fourier power spectrum and a wavelet kurtosis indicator of temporal intermittency is observed. A possible interpretation of this anti-correlation is developed using a "dripping handrail" transient chaos model.

Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission

Intermittent and Transient Behavior in Cygnus X-1 and GRS 1915+105 X-ray Emission PDF Author: Daniel V. Engovatov
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Much work has been done on trying to gain insight into the dynamics of accreting systems, such as black hole and neutron star binaries, by analyzing timing measurements from X-ray telescopes. In this thesis we present a novel approach to this problem using a kurtosis measure of the wavelet distribution obtained from the light curve to quantify the presence of intermittent activity. This method is applied to large RXTE data sets for GRS 1915+105, and Cygnus X-1. We demonstrate a new approach to reveal bursting modes. Negative correlation between the presence of a low frequency QPO in the Cygnus X-1 Fourier power spectrum and a wavelet kurtosis indicator of temporal intermittency is observed. A possible interpretation of this anti-correlation is developed using a "dripping handrail" transient chaos model.

Spectral-temporal Correlations in the X-ray Emission of Cygnus X-1

Spectral-temporal Correlations in the X-ray Emission of Cygnus X-1 PDF Author: Moritz Böck
Publisher:
ISBN:
Category :
Languages : en
Pages : 89

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Book Description


Timing Neutron Stars: Pulsations, Oscillations and Explosions

Timing Neutron Stars: Pulsations, Oscillations and Explosions PDF Author: Tomaso M. Belloni
Publisher: Springer Nature
ISBN: 366262110X
Category : Science
Languages : en
Pages : 335

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Book Description
Neutron stars, whether isolated or in a binary system, display a varied and complex phenomenology, often accompanied by extreme variability of many time scales, which takes the form of pulsations due to the object rotation, quasi-periodicities associated to accretion of matter, and explosions due to matter accreted on the surface or to starquakes of highly magnetized objects. This book gives an overview of the current observational and theoretical standpoint in the research on the physics under the extreme conditions that neutron stars naturally provide. The six chapters explore three physical regions of a neutron star: the space around it, where accretion and pulsar companions allow testing of general relativity its surface, where millisecond pulsation and X-ray burts provide clues about general relativistic effects and the equation of state of neutron matter its interior, of course, inaccessible to direct observations, can nevertheless, be probed with all observational parameters related to neutron star variability.

The Universe in Gamma Rays

The Universe in Gamma Rays PDF Author: Volker Schönfelder
Publisher: Springer Science & Business Media
ISBN: 3662045931
Category : Science
Languages : en
Pages : 418

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Book Description
After describing cosmic gamma-ray production and absorption, the instrumentation used in gamma-ray astronomy is explained. The main part of the book deals with astronomical results, including the somewhat surprising result that the gamma-ray sky is continuously changing.

Fifty Years of Quasars

Fifty Years of Quasars PDF Author: Mauro D'Onofrio
Publisher: Springer
ISBN: 9783642443848
Category : Science
Languages : en
Pages : 0

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Book Description
The 50th anniversary of the discovery of quasars in 1963 presents an interesting opportunity to ask questions about the current state of quasar research. Formatted as a series of interviews with noted researchers in the field, each of them asked to address a specific set of questions covering topics selected by the editors, this book deals with the historical development of quasar research and discusses how advances in instrumentation and computational capabilities have benefitted quasar astronomy and have changed our basic understanding of quasars. In the last part of the book the interviews address the current topic of the role of quasars in galaxy evolution. They summarise open issues in understanding active galactic nuclei and quasars and present an outlook regarding what future observational facilities both on the ground and in space might reveal. Its interview format, the fascinating topic of quasars and black holes, and the lively recollections and at times controversial views of the contributors make this book both rewarding and a pleasure to read!

Pulsar Astronomy

Pulsar Astronomy PDF Author: Andrew Lyne
Publisher: Cambridge University Press
ISBN: 1107010144
Category : Science
Languages : en
Pages : 375

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Book Description
Now in its fourth edition, Pulsar Astronomy provides a thoroughly revised and updated introduction to the field of pulsar astronomy.

Physics of Relativistic Objects in Compact Binaries: from Birth to Coalescence

Physics of Relativistic Objects in Compact Binaries: from Birth to Coalescence PDF Author: Monica Colpi
Publisher: Springer Science & Business Media
ISBN: 1402092644
Category : Science
Languages : en
Pages : 386

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Book Description
A very attractive feature of the theory of general relativity is that it is a perfectexampleofa“falsi?able”theory:notunableparameterispresentinthe theory and therefore even a single experiment incompatible with a prediction of the theory would immediately lead to its inevitable rejection, at least in the physical regime of application of the aforementioned experiment. This fact provides additional scienti?c value to one of the boldest and most fascinating achievements of the human intellect ever, and motivates a wealth of e?orts in designing and implementing tests aimed at the falsi?cation of the theory. The ?rst historical test on the theory has been the de?ection of light gr- ing the solar surface (Eddington 1919): the compatibility of the theory with this ?rst experiment together with its ability to explain the magnitude of the perihelion advance of Mercury contributed strongly to boost acceptance and worldwideknowledge.However,technologicallimitations preventedphysicists from setting up more constraining tests for several decades after the formu- tion of the theory. In fact, a relevant problem with experimental general r- ativity is that the predicted deviations from the Newtonian theory of gravity areverysmallwhentheexperimentsarecarriedoutinterrestriallaboratories.

Yearbook on Space Policy 2016

Yearbook on Space Policy 2016 PDF Author: Cenan Al-Ekabi
Publisher: Springer
ISBN: 3319724657
Category : Technology & Engineering
Languages : en
Pages : 342

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Book Description
The Yearbook on Space Policy, edited by the European Space Policy Institute (ESPI), is the reference publication analysing space policy developments. Each year it presents issues and trends in space policy and the space sector as a whole. Its scope is global and its perspective is European. The Yearbook also links space policy with other policy areas. It highlights specific events and issues, and provides useful insights, data and information on space activities. The first part of the Yearbook sets out a comprehensive overview of the economic, political, technological and institutional trends that have affected space activities. The second part of the Yearbook offers a more analytical perspective on the yearly ESPI theme and consists of external contributions written by professionals with diverse backgrounds and areas of expertise. The third part of the Yearbook carries forward the character of the Yearbook as an archive of space activities. The Yearbook is designed for government decision-makers and agencies, industry professionals, as well as the service sectors, researchers and scientists and the interested public.

Multiple Messengers and Challenges in Astroparticle Physics

Multiple Messengers and Challenges in Astroparticle Physics PDF Author: Roberto Aloisio
Publisher: Springer
ISBN: 331965425X
Category : Science
Languages : en
Pages : 554

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Book Description
This book, designed as a tool for young researchers and graduate students, reviews the main open problems and research lines in various fields of astroparticle physics: cosmic rays, gamma rays, neutrinos, cosmology, and gravitational physics. The opening section discusses cosmic rays of both galactic and extragalactic origin, examining experimental results, theoretical models, and possible future developments. The basics of gamma-ray astronomy are then described, including the detection methods and techniques. Galactic and extragalactic aspects of the field are addressed in the light of recent discoveries with space-borne and ground-based detectors. The review of neutrinos outlines the status of the investigations of neutrino radiation and brings together relevant formulae, estimations, and background information. Three complementary issues in cosmology are examined: observable predictions of inflation in the early universe, effects of dark energy/modified gravity in the large-scale structure of the universe, and neutrinos in cosmology and large-scale structures. The closing section on gravitational physics reviews issues relating to quantum gravity, atomic precision tests, space-based experiments, the strong field regime, gravitational waves, multi-messengers, and alternative theories of gravity.