The First Galaxies: Assembly under Radiative Feedback from the
... 2007b; Greif et al. 2008; Regan & Haehnelt 2009). On the other hand, simulations of galaxies inside halos with larger masses & 109 M⊙ and at lower redshifts z . 6 − 10 often find the halo gas organized in rotationally supported disks (e.g., Mashchenko et al. 2008; Pawlik et al. 2011; Romano-Dı́az et ...
... 2007b; Greif et al. 2008; Regan & Haehnelt 2009). On the other hand, simulations of galaxies inside halos with larger masses & 109 M⊙ and at lower redshifts z . 6 − 10 often find the halo gas organized in rotationally supported disks (e.g., Mashchenko et al. 2008; Pawlik et al. 2011; Romano-Dı́az et ...
Exospheres and Atmospheric Escape
... a simpler model for Mars atmosphere, but took into account the dependence of the recombination rate on the solar zenith angle and self-consistently coupled the atmosphere simulation to a 3D hybrid simulation of the interaction with the solar wind (Modolo et al. 2005). Monte Carlo simulations have ra ...
... a simpler model for Mars atmosphere, but took into account the dependence of the recombination rate on the solar zenith angle and self-consistently coupled the atmosphere simulation to a 3D hybrid simulation of the interaction with the solar wind (Modolo et al. 2005). Monte Carlo simulations have ra ...
Correlation of the highest-energy cosmic rays with the positions of
... Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest-energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) [Pierre Auger Collaboration, Science 318 (2007) 938]. The c ...
... Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest-energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) [Pierre Auger Collaboration, Science 318 (2007) 938]. The c ...
This presentation
... Computer-generated image illustrates the excess high-energy gamma-ray emission surrounding the Milky Way, found by scientists at the University of California, Riverside, Clemson University and the University of Chicago. Violet and blue portions represent the halo of gamma rays far off the galactic p ...
... Computer-generated image illustrates the excess high-energy gamma-ray emission surrounding the Milky Way, found by scientists at the University of California, Riverside, Clemson University and the University of Chicago. Violet and blue portions represent the halo of gamma rays far off the galactic p ...
Cosmic Rays
... Secondary Isotopes with lifetime ~esc can be used to directly measure the age of CR ...
... Secondary Isotopes with lifetime ~esc can be used to directly measure the age of CR ...
cosmic-ray neon, wolf-rayet stars, and the superbubble origin of
... Dessart et al. 2000). This is consistent with a large 22 Ne excess and gives support to the idea of Cassé & Paul (1982). The highvelocity winds that are characteristic of W-R stars can inject the surface material into regions where standing shocks, formed by those winds and the winds of the hot, yo ...
... Dessart et al. 2000). This is consistent with a large 22 Ne excess and gives support to the idea of Cassé & Paul (1982). The highvelocity winds that are characteristic of W-R stars can inject the surface material into regions where standing shocks, formed by those winds and the winds of the hot, yo ...
Thermal history of the universe with dark energy
... universe is highly homogeneous, isotropic and flat, composed by approximately 72% of dark energy, 23% of dark matter and 5% of baryonic matter [11], which is known as the ΛCDM model. Other hypotheses consider the dark components as a missing part of gravitation and thus base themselves on modified g ...
... universe is highly homogeneous, isotropic and flat, composed by approximately 72% of dark energy, 23% of dark matter and 5% of baryonic matter [11], which is known as the ΛCDM model. Other hypotheses consider the dark components as a missing part of gravitation and thus base themselves on modified g ...
STELLAR SPECTRA A. Basic Line Formation
... development of more general line-formation theory, especially radiation transport through resonance scattering; – Avrett, Auer, Mihalas, Hummer, Rybicki and many others, from 1965: application of computers to model non-LTE line formation numerically. ...
... development of more general line-formation theory, especially radiation transport through resonance scattering; – Avrett, Auer, Mihalas, Hummer, Rybicki and many others, from 1965: application of computers to model non-LTE line formation numerically. ...
Spin light of neutrino in matter and electromagnetic fields
... discover a mechanism for electromagnetic radiation generated by the neutrino magnetic (and/or electric) moment rotation which occurs due to electroweak interaction with the background environment. It should be noted that generalization to the case of a photon emission by neutrino due to the neutrino ...
... discover a mechanism for electromagnetic radiation generated by the neutrino magnetic (and/or electric) moment rotation which occurs due to electroweak interaction with the background environment. It should be noted that generalization to the case of a photon emission by neutrino due to the neutrino ...
Matter and antimatter in the same universe?
... There are still several problems in the inflationary model related to the exact definition of the energy density function (Coleman-Weinberg) describing the Higgs fields in order to obtain a proper phase transition; moreover, it is probably in the framework of a new class of superunification theories ...
... There are still several problems in the inflationary model related to the exact definition of the energy density function (Coleman-Weinberg) describing the Higgs fields in order to obtain a proper phase transition; moreover, it is probably in the framework of a new class of superunification theories ...
Radiatively driven Rayleigh-Taylor instability candidates around a
... Rayleigh-Taylor instabilities (RTI) in the outflow bubble where radiation itself behaves like a lighter fluid penetrating into the denser gaseous matter (heavy fluid) surrounding the star. The optically thin gaps in between the RTI allowed radiation to escape, and the overdense material falls back t ...
... Rayleigh-Taylor instabilities (RTI) in the outflow bubble where radiation itself behaves like a lighter fluid penetrating into the denser gaseous matter (heavy fluid) surrounding the star. The optically thin gaps in between the RTI allowed radiation to escape, and the overdense material falls back t ...
Cosmological solutions of the Einstein
... This does not mean, however, that at later times when the other energy density components come in to play and even dominate the scene we have to expect a flat space one. In fact the observed energy density at present is close to the critical one. This we will discuss later. Even if one counts the no ...
... This does not mean, however, that at later times when the other energy density components come in to play and even dominate the scene we have to expect a flat space one. In fact the observed energy density at present is close to the critical one. This we will discuss later. Even if one counts the no ...
Physical Processes of Gamma Ray Emission in Astrophysics
... See prof. B.S.Acharya talk on WAPP 2012 Radiation ,3rd Ed., (1954), p.386. ...
... See prof. B.S.Acharya talk on WAPP 2012 Radiation ,3rd Ed., (1954), p.386. ...
The destruction and survival of polycyclic aromatic hydrocarbons in
... PAH destruction process unimolecular dissociation and present a simplified scheme to estimate the location from the star at which the molecules become photo-stable. We find that soft photons with energies below ∼20 eV dissociate PAHs only up to short distances from the star (r < 1 AU); whereas disso ...
... PAH destruction process unimolecular dissociation and present a simplified scheme to estimate the location from the star at which the molecules become photo-stable. We find that soft photons with energies below ∼20 eV dissociate PAHs only up to short distances from the star (r < 1 AU); whereas disso ...
Dissipation and heating in solar wind turbulence: from the macro to
... Plasmas exhibit diverse physical phenomena which range from macroscopic scales on the size of planetary and galactic systems where the plasma is behaving as a turbulent fluid with random intermittent magnetic field fluctuations, the so-called ‘magneto-hydrodynamics’ (MHD); to micro-scale kinetic phy ...
... Plasmas exhibit diverse physical phenomena which range from macroscopic scales on the size of planetary and galactic systems where the plasma is behaving as a turbulent fluid with random intermittent magnetic field fluctuations, the so-called ‘magneto-hydrodynamics’ (MHD); to micro-scale kinetic phy ...
Lecture 01 - BITS Pilani
... Blackbody Radiation: Explanation I. Rayleigh-Jeans Explanation (1900-1905) The Rayleigh-Jeans Radiation Law was a useful but not completely successful attempt at establishing the functional form of the spectra of thermal radiation through classical arguments. This attempt was based on certain assum ...
... Blackbody Radiation: Explanation I. Rayleigh-Jeans Explanation (1900-1905) The Rayleigh-Jeans Radiation Law was a useful but not completely successful attempt at establishing the functional form of the spectra of thermal radiation through classical arguments. This attempt was based on certain assum ...
DEPT OF PHYSICS AND ASTRONOMY M.Sc
... analysis and interpretation, conclusions. Study of various research designs, Historical, Case studies, Surveys, Experimental, etc Analysis, Surveys and synthesis of conceptual and philosophical foundationDescriptive, Cross sectional, foundations of different disciplines. Identification of research p ...
... analysis and interpretation, conclusions. Study of various research designs, Historical, Case studies, Surveys, Experimental, etc Analysis, Surveys and synthesis of conceptual and philosophical foundationDescriptive, Cross sectional, foundations of different disciplines. Identification of research p ...
The role of the sun in climate forcing
... The Sun is by far the most important driving force of the climate system. However, only little is known how variable this force is acting on di!erent time scales ranging from minutes to millennia and how the climate system reacts to changes in this forcing. Changes of the global insolation can be re ...
... The Sun is by far the most important driving force of the climate system. However, only little is known how variable this force is acting on di!erent time scales ranging from minutes to millennia and how the climate system reacts to changes in this forcing. Changes of the global insolation can be re ...
Health threat from cosmic rays
The health threat from cosmic rays is the danger posed by galactic cosmic rays and solar energetic particles to astronauts on interplanetary missions. Galactic cosmic rays (GCRs) consist of high energy protons (85%), helium (14%) and other high energy nuclei (HZE ions). Solar energetic particles consist primarily of protons accelerated by the Sun to high energies via proximity to solar flares and coronal mass ejections. They are one of the most important barriers standing in the way of plans for interplanetary travel by crewed spacecraft.