CANGAROO and VHE γ-ray Astronomy: Past, present and future
... absolute flux of extended emission ? spectral shape ------ emission map of sources Max Acc energy: Emax to compare with ~1015eV (knee of CRs) Approach from Σ(point-like sources) from diffuse emission corresponding to CR spectrum ...
... absolute flux of extended emission ? spectral shape ------ emission map of sources Max Acc energy: Emax to compare with ~1015eV (knee of CRs) Approach from Σ(point-like sources) from diffuse emission corresponding to CR spectrum ...
Astrophysics
... information important for understanding how particles are accelerated to high energies in astrophysical shock waves, and how pulsars produce their relativistic winds of material. Cosmic Rays are the highest energy particles observed from space. Prof. Ellison studies the production of energetic parti ...
... information important for understanding how particles are accelerated to high energies in astrophysical shock waves, and how pulsars produce their relativistic winds of material. Cosmic Rays are the highest energy particles observed from space. Prof. Ellison studies the production of energetic parti ...
Conception of Generations
... on the ground level. One of them was identified as a decay of a neutral particle and the other as that of a charged one. It was just the time when pions started to be identified and the time was not yet ripe to identify them. They were first called V particles from the shape of the fork tracks and late ...
... on the ground level. One of them was identified as a decay of a neutral particle and the other as that of a charged one. It was just the time when pions started to be identified and the time was not yet ripe to identify them. They were first called V particles from the shape of the fork tracks and late ...
V. Sahakian
... The six sources from these eights there are counterparts at other wavelengths. However, for the two sources, HESS J1813-178 and HESS J1614-518, no counterparts have been found at other wavelengths. HESS J1813-178 resembles the unidentified TeV source discovered by HEGRA, TeV J2032+4130, and the firs ...
... The six sources from these eights there are counterparts at other wavelengths. However, for the two sources, HESS J1813-178 and HESS J1614-518, no counterparts have been found at other wavelengths. HESS J1813-178 resembles the unidentified TeV source discovered by HEGRA, TeV J2032+4130, and the firs ...
On the Properties and Topology of the Cosmic Web Environments
... • 3 Milky Way (MW) satellites with maximum velocity > 30 km/s ...
... • 3 Milky Way (MW) satellites with maximum velocity > 30 km/s ...
The Physical Nature of Cosmic Accretion of Baryons and Dark Matter
... our assumed mass profile inside the halo. For example, using an isothermal profile instead of NFW gives results that are consistent at the ∼ 10% level. Figure 2 shows the predicted values of the enclosed overdensity. Throughout this paper, we define overdensities relative to the mean matter density, ...
... our assumed mass profile inside the halo. For example, using an isothermal profile instead of NFW gives results that are consistent at the ∼ 10% level. Figure 2 shows the predicted values of the enclosed overdensity. Throughout this paper, we define overdensities relative to the mean matter density, ...
Correlation of the highest-energy cosmic rays with the positions of
... the observed flux above 6 1019 eV. Protons with higher energies interact with cosmic microwave background photons to produce pions [3,4], which leads to a significant attenuation of their flux from more distant sources. The energy of light nuclei is damped over an even shorter length scale due to pho ...
... the observed flux above 6 1019 eV. Protons with higher energies interact with cosmic microwave background photons to produce pions [3,4], which leads to a significant attenuation of their flux from more distant sources. The energy of light nuclei is damped over an even shorter length scale due to pho ...
Constraints on the Production of Ultra–High
... UHECRs, the particles originate from within the light cylinder, and rotation is the source of power. We next examine whether these models can give the observed composition of cosmic rays and accelerate particles to the requisite energies, and if microphysical energy loss processes produce strong cut ...
... UHECRs, the particles originate from within the light cylinder, and rotation is the source of power. We next examine whether these models can give the observed composition of cosmic rays and accelerate particles to the requisite energies, and if microphysical energy loss processes produce strong cut ...
The Search for the Source of the Highest Energy Cosmic Rays
... Although imaginative arguments actually do exist to avoid this conclusion, it is generally believed that our galaxy is too small and its magnetic field too weak to accelerate the highest energy cosmic rays. Those with energy ...
... Although imaginative arguments actually do exist to avoid this conclusion, it is generally believed that our galaxy is too small and its magnetic field too weak to accelerate the highest energy cosmic rays. Those with energy ...
Jupiter
... the axis of the shower — is not completely attenuated as it escapes the atmosphere. These conditions constrain detectable cosmic rays to trajectories that skim the atmosphere of Jupiter, as described by Rimmer et al. (2014) and illustrated in Figure 5. The detection region is an annulus around Jupi ...
... the axis of the shower — is not completely attenuated as it escapes the atmosphere. These conditions constrain detectable cosmic rays to trajectories that skim the atmosphere of Jupiter, as described by Rimmer et al. (2014) and illustrated in Figure 5. The detection region is an annulus around Jupi ...
Lesson 1-0 Slides The Cosmic Landscape
... What makes up our solar system? How can we measure distances? What is the Milky Way? What is your universal address? ...
... What makes up our solar system? How can we measure distances? What is the Milky Way? What is your universal address? ...
Particle Physics and Cosmology
... What is Dark Matter? • Must be neutral, very long-lived, heavy. • All known particles are easily eliminated. • Dark matter is the best evidence that the standard model of particle physics is incomplete, and motivates many extensions. • Some candidates: – WIMPs (e.g., neutralinos) – Axions 21 August ...
... What is Dark Matter? • Must be neutral, very long-lived, heavy. • All known particles are easily eliminated. • Dark matter is the best evidence that the standard model of particle physics is incomplete, and motivates many extensions. • Some candidates: – WIMPs (e.g., neutralinos) – Axions 21 August ...
∫ Formation of a Local Atmospheric Electric Field
... at the maximum reaches 30 cm–3 s–1, and the altitude range of the maximum ionization region is 16–10, i.e., about 7 km, which indicates the significant effect of cosmic rays on the integral conductivity. The high sta bility of cosmic ray intensity, except for the Forbush decrease, causes relatively ...
... at the maximum reaches 30 cm–3 s–1, and the altitude range of the maximum ionization region is 16–10, i.e., about 7 km, which indicates the significant effect of cosmic rays on the integral conductivity. The high sta bility of cosmic ray intensity, except for the Forbush decrease, causes relatively ...
Magnetic Monopoles
... Experiments are conducted to measure a flux of magnetic monopoles that hit the earth as cosmic rays ...
... Experiments are conducted to measure a flux of magnetic monopoles that hit the earth as cosmic rays ...
Non-variable cosmologically distant gamma
... to the acceleration site of UHE protons. Note that the considerable contribution to the high-energy electrons is provided by the gamma rays produced in decay of mesons. The interaction of these gamma rays with cosmic radio background radiation occurs in the regime when most of the energy goes to one ...
... to the acceleration site of UHE protons. Note that the considerable contribution to the high-energy electrons is provided by the gamma rays produced in decay of mesons. The interaction of these gamma rays with cosmic radio background radiation occurs in the regime when most of the energy goes to one ...
Results from the AMANDA Neutrino Telescope
... AMANDA has been operating for almost one decade. No extraterrestrial neutrino has been observed above the atmospheric background, YET… Increasingly stringent limits have been set in but sometimes point-like sources, diffuse fluxes, neutralinos… success comes A bigger detector is needed IceCube aft ...
... AMANDA has been operating for almost one decade. No extraterrestrial neutrino has been observed above the atmospheric background, YET… Increasingly stringent limits have been set in but sometimes point-like sources, diffuse fluxes, neutralinos… success comes A bigger detector is needed IceCube aft ...
Project Gamma - World of Teaching
... gamma ray burst for over an hour, with some gamma rays having energies over a GeV and two having energies over 10 GeV. The observation of an increased fraction of pulsar electromagnetic radiation going into gamma rays as the age of the pulsar increases to a million years The determination with high ...
... gamma ray burst for over an hour, with some gamma rays having energies over a GeV and two having energies over 10 GeV. The observation of an increased fraction of pulsar electromagnetic radiation going into gamma rays as the age of the pulsar increases to a million years The determination with high ...
This presentation
... explosion. The image at the right is taken from the BATSE instrument on NASA’s Compton Gamma Ray Observatory. Spot size=peak flux during gamma ray bursts. Spot color= average energy, blue is of highest energy. It is clear that they don’t come from our galaxy, so in order for us to see them they must ...
... explosion. The image at the right is taken from the BATSE instrument on NASA’s Compton Gamma Ray Observatory. Spot size=peak flux during gamma ray bursts. Spot color= average energy, blue is of highest energy. It is clear that they don’t come from our galaxy, so in order for us to see them they must ...
X Rays and Gamma Rays: Crookes Tubes and Nuclear Light
... light with longer wavelength. While microwave light can be used to image through certain materials such as dry dirt or sand quite well, it cannot penetrate effectively through conductive materials such as water or metal. X rays and gamma rays, however, can penetrate all known materials. While visibl ...
... light with longer wavelength. While microwave light can be used to image through certain materials such as dry dirt or sand quite well, it cannot penetrate effectively through conductive materials such as water or metal. X rays and gamma rays, however, can penetrate all known materials. While visibl ...
Gamma Ray Bursts
... neutron stars in a binary. Also, some think, they could be from the same process as the long GRB but were not directly along the axis of the emission, i.e. not seeing it face on. ...
... neutron stars in a binary. Also, some think, they could be from the same process as the long GRB but were not directly along the axis of the emission, i.e. not seeing it face on. ...
Cosmic Rays near Proxima Centauri b
... and references within). Cosmic rays as a factor of space weather were considered only by one group, possibly, their first and most cited work in this regard is Grießmeier et al. (2005). The dependence of the Galactic cosmic rays (GCR) induced radiation dose on the strength of the planetary magnetic ...
... and references within). Cosmic rays as a factor of space weather were considered only by one group, possibly, their first and most cited work in this regard is Grießmeier et al. (2005). The dependence of the Galactic cosmic rays (GCR) induced radiation dose on the strength of the planetary magnetic ...
The Case for a Kilometer-Scale High Energy Neutrino Detector
... hole which powers the galaxy) which are a characteristic feature of these radio-loud active galaxies. Many arguments have been given for the acceleration of protons as well as electrons. Inevitably beams of gamma rays and neutrinos from the decay of pions appear along the jets. The pions are photopr ...
... hole which powers the galaxy) which are a characteristic feature of these radio-loud active galaxies. Many arguments have been given for the acceleration of protons as well as electrons. Inevitably beams of gamma rays and neutrinos from the decay of pions appear along the jets. The pions are photopr ...
Cosmic ray
Cosmic rays are immensely high-energy radiation, mainly originating outside the Solar System. They may produce showers of secondary particles that penetrate and impact the Earth's atmosphere and sometimes even reach the surface. Composed primarily of high-energy protons and atomic nuclei, they are of mysterious origin. Data from the Fermi space telescope (2013) has been interpreted as evidence that a significant fraction of primary cosmic rays originate from the supernovae of massive stars. However, this is not thought to be their only source. Active galactic nuclei probably also produce cosmic rays.The term ray is a historical accident, as cosmic rays were at first, and wrongly, thought to be mostly electromagnetic radiation. In common scientific usage high-energy particles with intrinsic mass are known as ""cosmic"" rays, and photons, which are quanta of electromagnetic radiation (and so have no intrinsic mass) are known by their common names, such as ""gamma rays"" or ""X-rays"", depending on their origin.Cosmic rays attract great interest practically, due to the damage they inflict on microelectronics and life outside the protection of an atmosphere and magnetic field, and scientifically, because the energies of the most energetic ultra-high-energy cosmic rays (UHECRs) have been observed to approach 3 × 1020 eV, about 40 million times the energy of particles accelerated by the Large Hadron Collider. One can show that such enormous energies might be achieved by means of the Centrifugal mechanism of acceleration in Active galactic nuclei. At 50 J, the highest-energy ultra-high-energy cosmic rays have energies comparable to the kinetic energy of a 90-kilometre-per-hour (56 mph) baseball. As a result of these discoveries, there has been interest in investigating cosmic rays of even greater energies. Most cosmic rays, however, do not have such extreme energies; the energy distribution of cosmic rays peaks at 0.3 gigaelectronvolts (4.8×10−11 J).Of primary cosmic rays, which originate outside of Earth's atmosphere, about 99% are the nuclei (stripped of their electron shells) of well-known atoms, and about 1% are solitary electrons (similar to beta particles). Of the nuclei, about 90% are simple protons, i. e. hydrogen nuclei; 9% are alpha particles, and 1% are the nuclei of heavier elements, called HZE ions. A very small fraction are stable particles of antimatter, such as positrons or antiprotons. The precise nature of this remaining fraction is an area of active research. An active search from Earth orbit for anti-alpha particles has failed to detect them.