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


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


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.




The Universe in Gamma Rays


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


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


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


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 2017


Book Description

The book describes the recent trends in space policy and the space sector overall. While maintaining a global scope with a European perspective, it links space policy with other policy areas, highlights major events, and provides insights on the latest data. The Yearbook includes the proceedings of ESPI's 12th Autumn Conference, which discussed the growing importance of Security in Outer Space and the stakes for civilian space programmes in the public and private sectors. Bringing together satellite operators, SMEs, European and American institutions, and think tanks, the Autumn Conference served as platform for fresh insights on security in outer space and the potential of transatlantic relations to address its challenges. The Yearbook also includes executive summaries of ESPI's work in 2017 as well as ESPI's 2017 Executive Briefs, covering topics such as suborbital spaceflight, super heavy lift launch vehicles, collaboration with China, and the delimitation of outer space. All in all, the book gives a detailed review of space policy developments worldwide, contextualised with information about national-level space industries and activity and broader political and economic conditions. The readership is expected to include the staff of space agencies, the space industry, and the space law and policy research community.




Multiple Messengers and Challenges in Astroparticle Physics


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.




Astrophysical Black Holes


Book Description

Based on graduate school lectures in contemporary relativity and gravitational physics, this book gives a complete and unified picture of the present status of theoretical and observational properties of astrophysical black holes. The chapters are written by internationally recognized specialists. They cover general theoretical aspects of black hole astrophysics, the theory of accretion and ejection of gas and jets, stellar-sized black holes observed in the Milky Way, the formation and evolution of supermassive black holes in galactic centers and quasars as well as their influence on the dynamics in galactic nuclei. The final chapter addresses analytical relativity of black holes supporting theoretical understanding of the coalescence of black holes as well as being of great relevance in identifying gravitational wave signals. With its introductory chapters the book is aimed at advanced graduate and post-graduate students, but it will also be useful for specialists.




High-Energy Emission from Pulsars and their Systems


Book Description

The aim of the inaugural meeting of the Sant Cugat Forum on Astrophysics was to address, in a global context, the current understanding of and challenges in high-energy emissions from isolated and non-isolated neutron stars, and to confront the theoretical picture with observations of both the Fermi satellite and the currently operating ground-based Cherenkov telescopes. Participants have also discussed the prospects for possible observations with planned instruments across the multi-wavelength spectrum (e.g. SKA, LOFAR, E-VLT, IXO, CTA) and how they will impact our theoretical understanding of these systems. In keeping with the goals of the Forum, this book not only represents the proceedings of the meeting, but also a reflection on the state-of-the-art in the topic.