Author: Edo Berger
Publisher: Universal-Publishers
ISBN: 1581122330
Category : Science
Languages : en
Pages : 206
Book Description
The diversity of stellar death is revealed in the energy, velocity and geometry of the explosion debris ("ejecta''). Using multi-wavelength observations of gamma-ray burst (GRB) afterglows I show that GRBs, arising from the death of massive stars, are marked by relativistic, collimated ejecta ("jets'') with a wide range of opening angles. These results suggest that various cosmic explosions are powered by a common energy source, an "engine'' (possibly an accreting stellar-mass black hole), with their diverse appearances determined solely by the variable high velocity output. On the other hand, using radio observations I show that local type Ibc core-collapse supernovae generally lack relativistic ejecta and are therefore not powered by engines. Instead, the highest velocity debris in these sources, typically with a velocity lower than 100,000 km/sec, are produced in the (effectively) spherical ejection of the stellar envelope. The relative rates of engine- and collapse-powered explosions suggest that the former account for only a small fraction of the stellar death rate. Using the first radio and submillimeter observations of GRB hosts, I show that some are extreme starburst galaxies with the bursts directly associated with the regions of most intense star formation. I suggest, by comparison to other well-studied samples, that GRBs preferentially occur in sub-luminous, low mass galaxies, undergoing the early stages of a starburst process. If confirmed with future observations, this trend will place GRBs in the forefront of star formation and galaxy evolution studies.
Cosmic Explosions
Author: Edo Berger
Publisher: Universal-Publishers
ISBN: 1581122330
Category : Science
Languages : en
Pages : 206
Book Description
The diversity of stellar death is revealed in the energy, velocity and geometry of the explosion debris ("ejecta''). Using multi-wavelength observations of gamma-ray burst (GRB) afterglows I show that GRBs, arising from the death of massive stars, are marked by relativistic, collimated ejecta ("jets'') with a wide range of opening angles. These results suggest that various cosmic explosions are powered by a common energy source, an "engine'' (possibly an accreting stellar-mass black hole), with their diverse appearances determined solely by the variable high velocity output. On the other hand, using radio observations I show that local type Ibc core-collapse supernovae generally lack relativistic ejecta and are therefore not powered by engines. Instead, the highest velocity debris in these sources, typically with a velocity lower than 100,000 km/sec, are produced in the (effectively) spherical ejection of the stellar envelope. The relative rates of engine- and collapse-powered explosions suggest that the former account for only a small fraction of the stellar death rate. Using the first radio and submillimeter observations of GRB hosts, I show that some are extreme starburst galaxies with the bursts directly associated with the regions of most intense star formation. I suggest, by comparison to other well-studied samples, that GRBs preferentially occur in sub-luminous, low mass galaxies, undergoing the early stages of a starburst process. If confirmed with future observations, this trend will place GRBs in the forefront of star formation and galaxy evolution studies.
Publisher: Universal-Publishers
ISBN: 1581122330
Category : Science
Languages : en
Pages : 206
Book Description
The diversity of stellar death is revealed in the energy, velocity and geometry of the explosion debris ("ejecta''). Using multi-wavelength observations of gamma-ray burst (GRB) afterglows I show that GRBs, arising from the death of massive stars, are marked by relativistic, collimated ejecta ("jets'') with a wide range of opening angles. These results suggest that various cosmic explosions are powered by a common energy source, an "engine'' (possibly an accreting stellar-mass black hole), with their diverse appearances determined solely by the variable high velocity output. On the other hand, using radio observations I show that local type Ibc core-collapse supernovae generally lack relativistic ejecta and are therefore not powered by engines. Instead, the highest velocity debris in these sources, typically with a velocity lower than 100,000 km/sec, are produced in the (effectively) spherical ejection of the stellar envelope. The relative rates of engine- and collapse-powered explosions suggest that the former account for only a small fraction of the stellar death rate. Using the first radio and submillimeter observations of GRB hosts, I show that some are extreme starburst galaxies with the bursts directly associated with the regions of most intense star formation. I suggest, by comparison to other well-studied samples, that GRBs preferentially occur in sub-luminous, low mass galaxies, undergoing the early stages of a starburst process. If confirmed with future observations, this trend will place GRBs in the forefront of star formation and galaxy evolution studies.
The Cosmic Explosion
Author: Jayant Vishnu Narlikar
Publisher:
ISBN:
Category : Marathi fiction
Languages : en
Pages : 104
Book Description
The Story Begins In The Seventh Century During The Region Of The King Harshavardhna. Bhikku Sariputta, The Head Of The Buddhist Vihar At Sthanvishwar Is A Keen Observer Of The Star-Studded Heavens. His Pet Student Rohit Witnesses A Remarkable Sight In The Sky And Rushes To His Teacher For Guidance. Sariputta Suspects That The Event Is Of Such Great Significance That He Immediately Reports It To The King. At The KingýS Behest With RohitýS Help Sariputta Prepares Meticulous Records Of The Event Which The Buried Underground For Posterity. It Is In The Twentieth Century That The Records In The Form Of Brass Plates Are Accidentally Unearthed. Tatyasaheb Bhagvat, A Scholar On Ancient Indian Studies And The Astrophysicist Avinash Nene Together Find Might Have Momentus Implications For The Earth And Its Inhabitants. Did The Event Records By Sariputta Spell Doom? The Final Part Of The Novel Tells Us What Happened Several More Centuries Later...
Publisher:
ISBN:
Category : Marathi fiction
Languages : en
Pages : 104
Book Description
The Story Begins In The Seventh Century During The Region Of The King Harshavardhna. Bhikku Sariputta, The Head Of The Buddhist Vihar At Sthanvishwar Is A Keen Observer Of The Star-Studded Heavens. His Pet Student Rohit Witnesses A Remarkable Sight In The Sky And Rushes To His Teacher For Guidance. Sariputta Suspects That The Event Is Of Such Great Significance That He Immediately Reports It To The King. At The KingýS Behest With RohitýS Help Sariputta Prepares Meticulous Records Of The Event Which The Buried Underground For Posterity. It Is In The Twentieth Century That The Records In The Form Of Brass Plates Are Accidentally Unearthed. Tatyasaheb Bhagvat, A Scholar On Ancient Indian Studies And The Astrophysicist Avinash Nene Together Find Might Have Momentus Implications For The Earth And Its Inhabitants. Did The Event Records By Sariputta Spell Doom? The Final Part Of The Novel Tells Us What Happened Several More Centuries Later...
Supernova Explosions
Author: David Branch
Publisher: Springer
ISBN: 3662550547
Category : Science
Languages : en
Pages : 719
Book Description
Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpretations of such data, and an overview of the evolution of stars that brings them to an explosive endpoint. Part 2 goes into more detail on core-collapse and superluminous events: which kinds of stars produce them, and how do they do it? Part 3 is concerned with the stellar progenitors and explosion mechanisms of thermonuclear (Type Ia) supernovae. Part 4 is about consequences of supernovae and some applications to astrophysics and cosmology. References are provided in sufficient number to help the reader enter the literature.
Publisher: Springer
ISBN: 3662550547
Category : Science
Languages : en
Pages : 719
Book Description
Targeting advanced students of astronomy and physics, as well as astronomers and physicists contemplating research on supernovae or related fields, David Branch and J. Craig Wheeler offer a modern account of the nature, causes and consequences of supernovae, as well as of issues that remain to be resolved. Owing especially to (1) the appearance of supernova 1987A in the nearby Large Magellanic Cloud, (2) the spectacularly successful use of supernovae as distance indicators for cosmology, (3) the association of some supernovae with the enigmatic cosmic gamma-ray bursts, and (4) the discovery of a class of superluminous supernovae, the pace of supernova research has been increasing sharply. This monograph serves as a broad survey of modern supernova research and a guide to the current literature. The book’s emphasis is on the explosive phases of supernovae. Part 1 is devoted to a survey of the kinds of observations that inform us about supernovae, some basic interpretations of such data, and an overview of the evolution of stars that brings them to an explosive endpoint. Part 2 goes into more detail on core-collapse and superluminous events: which kinds of stars produce them, and how do they do it? Part 3 is concerned with the stellar progenitors and explosion mechanisms of thermonuclear (Type Ia) supernovae. Part 4 is about consequences of supernovae and some applications to astrophysics and cosmology. References are provided in sufficient number to help the reader enter the literature.
Cosmic Explosions
Author: J.M. Marcaide
Publisher: Springer Science & Business Media
ISBN: 354026633X
Category : Science
Languages : en
Pages : 575
Book Description
Supernovae are among the most energetic phenomena in the Universe and - lated to almost all aspects of modern astrophysics including starburst gal- ies, cosmic ray acceleration, neutron star and black hole formation, nuc- osynthesis and ISM chemical enrichment, energy input to the ISM, cosmic distance scale determination, dark energy related cosmological acceleration, gamma-ray bursts, extra-solar system neutrino burst detection, gravity wave generation, and many more. Additionally, the past 15 years have been p- ticularly productive with many new results and new understanding due in particular to the closest SN in 400 years in SN 1987A in the Large M- ellanic Cloud, and the unusually bright and close SN 1993J and SN 1994I in the nearby galaxies M81 and M51, respectively. In addition, the disc- ery of the ?-ray burst GRB 980425 and its related supernova SN 1998bw, and the con?rmation of GRB 030329/SN 2003dh, tied the study of SNe and GRBs inextricably together. With the many developments since the last - jor supernova meeting in La Serena, Chile in 1997, we felt that it was an appropriate time to bring together experts and students interested in the subject for a meeting where SN and GRB properties and interrelationships could be discussed. The tenth anniversary of SN 1993J provided such an - portunity and, appropriately, the meeting was held in Spain where SN 1993J was discovered on the early morning of 28 March 1993 by a Spanish amateur astronomer, Francisco Garc ́ ?a.
Publisher: Springer Science & Business Media
ISBN: 354026633X
Category : Science
Languages : en
Pages : 575
Book Description
Supernovae are among the most energetic phenomena in the Universe and - lated to almost all aspects of modern astrophysics including starburst gal- ies, cosmic ray acceleration, neutron star and black hole formation, nuc- osynthesis and ISM chemical enrichment, energy input to the ISM, cosmic distance scale determination, dark energy related cosmological acceleration, gamma-ray bursts, extra-solar system neutrino burst detection, gravity wave generation, and many more. Additionally, the past 15 years have been p- ticularly productive with many new results and new understanding due in particular to the closest SN in 400 years in SN 1987A in the Large M- ellanic Cloud, and the unusually bright and close SN 1993J and SN 1994I in the nearby galaxies M81 and M51, respectively. In addition, the disc- ery of the ?-ray burst GRB 980425 and its related supernova SN 1998bw, and the con?rmation of GRB 030329/SN 2003dh, tied the study of SNe and GRBs inextricably together. With the many developments since the last - jor supernova meeting in La Serena, Chile in 1997, we felt that it was an appropriate time to bring together experts and students interested in the subject for a meeting where SN and GRB properties and interrelationships could be discussed. The tenth anniversary of SN 1993J provided such an - portunity and, appropriately, the meeting was held in Spain where SN 1993J was discovered on the early morning of 28 March 1993 by a Spanish amateur astronomer, Francisco Garc ́ ?a.
Cosmic Horizons
Author: Steven Soter
Publisher:
ISBN: 9781565846029
Category : Science
Languages : en
Pages : 253
Book Description
Leading scientists offer a collection of essays that furnish illuminating explanations of recent discoveries in modern astrophysics--from the Big Bang to black holes--the possibility of life on other worlds, and the emerging technologies that make such research possible, accompanied by incisive profiles of such key figures as Carl Sagan and Georges Lemaetre. Original.
Publisher:
ISBN: 9781565846029
Category : Science
Languages : en
Pages : 253
Book Description
Leading scientists offer a collection of essays that furnish illuminating explanations of recent discoveries in modern astrophysics--from the Big Bang to black holes--the possibility of life on other worlds, and the emerging technologies that make such research possible, accompanied by incisive profiles of such key figures as Carl Sagan and Georges Lemaetre. Original.
The Physics of Gamma-Ray Bursts
Author: Bing Zhang
Publisher: Cambridge University Press
ISBN: 1107027616
Category : History
Languages : en
Pages : 617
Book Description
A complete text on the physics of gamma-ray bursts, the most brilliant explosions since the Big Bang.
Publisher: Cambridge University Press
ISBN: 1107027616
Category : History
Languages : en
Pages : 617
Book Description
A complete text on the physics of gamma-ray bursts, the most brilliant explosions since the Big Bang.
The Universe Is a Green Dragon
Author: Brian Swimme
Publisher: Simon and Schuster
ISBN: 1591435544
Category : Body, Mind & Spirit
Languages : en
Pages : 136
Book Description
Communicating his ideas in the form of a classical dialogue between a youth and a wise elder, cosmologist Brian Swimme crafts a fascinating exploration into the creativity suffusing the universe. His explication of the fundamental powers of the cosmos is mystical and ecstatic and points directly to the need to activate one’s own creative powers.
Publisher: Simon and Schuster
ISBN: 1591435544
Category : Body, Mind & Spirit
Languages : en
Pages : 136
Book Description
Communicating his ideas in the form of a classical dialogue between a youth and a wise elder, cosmologist Brian Swimme crafts a fascinating exploration into the creativity suffusing the universe. His explication of the fundamental powers of the cosmos is mystical and ecstatic and points directly to the need to activate one’s own creative powers.
The Little Book of the Big Bang
Author: Craig J. Hogan
Publisher: Springer Science & Business Media
ISBN: 1461216605
Category : Science
Languages : en
Pages : 188
Book Description
"Hogan compresses the fifteen-billion-year history of the Universe into a pleasurable evening. In a very direct way, he answers the questions everyone asks." -MARGARET GELLER, HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS "This delightful little primer brings you right up to the cutting edge of modern cosmology." -GEORGE SMOOT, PRINCIPAL INVESTIGATOR, COBE AND AUTHOR OF WRINKLES IN TIME "An excellent bridge by which the layperson can enter the domain of the Cosmos with understanding." -ROBERT WILLIAMS, DIRECTOR, SPACE TELESCOPE SCIENCE INSTITUTE
Publisher: Springer Science & Business Media
ISBN: 1461216605
Category : Science
Languages : en
Pages : 188
Book Description
"Hogan compresses the fifteen-billion-year history of the Universe into a pleasurable evening. In a very direct way, he answers the questions everyone asks." -MARGARET GELLER, HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS "This delightful little primer brings you right up to the cutting edge of modern cosmology." -GEORGE SMOOT, PRINCIPAL INVESTIGATOR, COBE AND AUTHOR OF WRINKLES IN TIME "An excellent bridge by which the layperson can enter the domain of the Cosmos with understanding." -ROBERT WILLIAMS, DIRECTOR, SPACE TELESCOPE SCIENCE INSTITUTE
The Many Facets of Cosmic Explosions
Author: Alicia Soderberg
Publisher: Universal-Publishers
ISBN: 1581123779
Category : Mathematics
Languages : en
Pages : 265
Book Description
Over the past few years, long-duration gamma-ray bursts (GRBs), including the subclass of X-ray flashes (XRFs), have been revealed to be a rare variety of Type Ibc supernova (SN Ibc). While all these events result from the death of massive stars, the electromagnetic luminosities of GRBs and XRFs exceed those of ordinary Type Ibc SNe by many orders of magnitude. The observed diversity of stellar death corresponds to large variations in the energy, velocity, and geometry of the explosion ejecta. Using multi-wavelength (radio, optical, X-ray) observations of the nearest GRBs, XRFs, and SNe Ibc, I show that GRBs and XRFs couple at least 1048 erg to relativistic material while SNe Ibc typically couple less than 1048 erg to their fastest (albeit non-relativistic) outflows. Specifically, I find that less than 3 percent of local SNe Ibc show any evidence for association with a GRB or XRF. Interestingly, this dichotomy is not echoed by the properties of their optical SN emission, dominated by the radioactive decay of Nickel-56; I find that GRBs, XRFs, and SNe Ibc show significant overlap in their optical peak luminosity and photospheric velocities. Recently, I identified a new class of GRBs and XRFs that are under-luminous in comparison with the statistical sample of GRBs. Owing to their faint high-energy emission, these sub-energetic bursts are only detectable nearby (z
Publisher: Universal-Publishers
ISBN: 1581123779
Category : Mathematics
Languages : en
Pages : 265
Book Description
Over the past few years, long-duration gamma-ray bursts (GRBs), including the subclass of X-ray flashes (XRFs), have been revealed to be a rare variety of Type Ibc supernova (SN Ibc). While all these events result from the death of massive stars, the electromagnetic luminosities of GRBs and XRFs exceed those of ordinary Type Ibc SNe by many orders of magnitude. The observed diversity of stellar death corresponds to large variations in the energy, velocity, and geometry of the explosion ejecta. Using multi-wavelength (radio, optical, X-ray) observations of the nearest GRBs, XRFs, and SNe Ibc, I show that GRBs and XRFs couple at least 1048 erg to relativistic material while SNe Ibc typically couple less than 1048 erg to their fastest (albeit non-relativistic) outflows. Specifically, I find that less than 3 percent of local SNe Ibc show any evidence for association with a GRB or XRF. Interestingly, this dichotomy is not echoed by the properties of their optical SN emission, dominated by the radioactive decay of Nickel-56; I find that GRBs, XRFs, and SNe Ibc show significant overlap in their optical peak luminosity and photospheric velocities. Recently, I identified a new class of GRBs and XRFs that are under-luminous in comparison with the statistical sample of GRBs. Owing to their faint high-energy emission, these sub-energetic bursts are only detectable nearby (z
On the Cosmic Horizon
Author: Jeffrey O. Bennett
Publisher: Benjamin-Cummings Publishing Company
ISBN:
Category : Science
Languages : en
Pages : 248
Book Description
"On the Cosmic Horizon reaches wide across the cosmos to provide lucid explanations for many of the most compelling cosmic questions. Following a Top Ten countdown, the book explores with wit and clarity each mystery and how it may be resolved. Each enigma is made accessible through a story which draws upon history and everyday human experience. Along the way, we learn about our state-of-the-art understanding of the universe, future missions, and the potential impact of unravelling these cosmic conundrums. On the Cosmic Horizon is the perfect book for anyone who wants to understand astronomical headlines and why they are important."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved
Publisher: Benjamin-Cummings Publishing Company
ISBN:
Category : Science
Languages : en
Pages : 248
Book Description
"On the Cosmic Horizon reaches wide across the cosmos to provide lucid explanations for many of the most compelling cosmic questions. Following a Top Ten countdown, the book explores with wit and clarity each mystery and how it may be resolved. Each enigma is made accessible through a story which draws upon history and everyday human experience. Along the way, we learn about our state-of-the-art understanding of the universe, future missions, and the potential impact of unravelling these cosmic conundrums. On the Cosmic Horizon is the perfect book for anyone who wants to understand astronomical headlines and why they are important."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved