
Belanger
... In early universe WIMPs are present in large number and they are in thermal equilibrium As the universe expanded and cooled their density is reduced through pair annihilation Eventually density is too low for annihilation process to keep up with expansion rate • Freeze-out temperature LSP decouples ...
... In early universe WIMPs are present in large number and they are in thermal equilibrium As the universe expanded and cooled their density is reduced through pair annihilation Eventually density is too low for annihilation process to keep up with expansion rate • Freeze-out temperature LSP decouples ...
Notes for course on Physics of Particles and Fields, CMI, Autumn
... physics, we may often treat pions, protons and neutrons as elementary, since the available energies of order MeV are too small to excite them (that would require about a 100 MeV). In fact, even an alpha particle (He−4 nucleus consisting of 2 protons and 2 neutrons) can be regarded as an elementary p ...
... physics, we may often treat pions, protons and neutrons as elementary, since the available energies of order MeV are too small to excite them (that would require about a 100 MeV). In fact, even an alpha particle (He−4 nucleus consisting of 2 protons and 2 neutrons) can be regarded as an elementary p ...
The Salpeter plasma correction for solar fusion reactions
... formula to compare with the Salpeter result, or with the various results of the rest of the heterodox “screening” literature. We can comment on some of their qualitative statements, with the caveat that we are not always sure how they have been implemented. The statements that we discuss below come ...
... formula to compare with the Salpeter result, or with the various results of the rest of the heterodox “screening” literature. We can comment on some of their qualitative statements, with the caveat that we are not always sure how they have been implemented. The statements that we discuss below come ...
Report - Jefferson Lab
... the first exclusive measurements of Deeply Virtual Compton Scattering, strongly suggestive of the manifestation of scattering at the quark level; high energy deuteron photodisintegration, illustrating for the first time the scales at which the meson-baryon description of a nucleus appears to be brea ...
... the first exclusive measurements of Deeply Virtual Compton Scattering, strongly suggestive of the manifestation of scattering at the quark level; high energy deuteron photodisintegration, illustrating for the first time the scales at which the meson-baryon description of a nucleus appears to be brea ...
Maximum Mass Restraint of Neutron Stars
... since it was determined that nucleons could no longer can support themselves at those densities. Finally, in 1959, Cameron used newly introduced nucleon-nucleon interaction to help evaluate superdense levels of neutron stars to obtain a mass of 2 solar masses. Cameron also discussed muons and hypero ...
... since it was determined that nucleons could no longer can support themselves at those densities. Finally, in 1959, Cameron used newly introduced nucleon-nucleon interaction to help evaluate superdense levels of neutron stars to obtain a mass of 2 solar masses. Cameron also discussed muons and hypero ...
F From Vibrating Strings to a Unified Theory of All Interactions
... Building blocks of the Standard Model There are four known forces in nature. The Standard Model of particle physics summarizes the present-day understanding of three of them. It describes the electromagnetic force, the weak force and the strong force, but leaves out the gravitational force. The Stan ...
... Building blocks of the Standard Model There are four known forces in nature. The Standard Model of particle physics summarizes the present-day understanding of three of them. It describes the electromagnetic force, the weak force and the strong force, but leaves out the gravitational force. The Stan ...
the standard model - Public < RHUL Physics Department TWiki
... In this case one needs a set of massless vector fields (three in the case of SU(2)), which were formally called “Yang-Mills” fields, but are now known as “gauge bosons”. • In order to apply such gauge theories to the weak interaction, considers particle transforming into each other under the weak in ...
... In this case one needs a set of massless vector fields (three in the case of SU(2)), which were formally called “Yang-Mills” fields, but are now known as “gauge bosons”. • In order to apply such gauge theories to the weak interaction, considers particle transforming into each other under the weak in ...
Event-by-Event Fluctuations of Net-Baryon distribution and higher
... in all cases the quadratic(2nd order) fluctuations rise rapidly in the transition region and approach to SB limit where the quartic(4th order) fluctuations show a maximum. This maximum is most pronounced for the baryon number fluctuations. the value 4 / 2 for net-baryon is about 1.0 when T< 200M ...
... in all cases the quadratic(2nd order) fluctuations rise rapidly in the transition region and approach to SB limit where the quartic(4th order) fluctuations show a maximum. This maximum is most pronounced for the baryon number fluctuations. the value 4 / 2 for net-baryon is about 1.0 when T< 200M ...
La Jolla 2006
... However, transport models w/o QGP produce to few pressure in the early stage above 30 GeV Marcus Bleicher, La Jolla 2006 ...
... However, transport models w/o QGP produce to few pressure in the early stage above 30 GeV Marcus Bleicher, La Jolla 2006 ...
Probing the stability of superheavy dark matter particles with high
... Universe from various astronomical and cosmological observations [1]. However, very fundamental properties of the dark matter particle such as the mass or the lifetime are still fairly unconstrained. An important restriction on dark matter models arises from large-scale N -body simulations [2, 3] wh ...
... Universe from various astronomical and cosmological observations [1]. However, very fundamental properties of the dark matter particle such as the mass or the lifetime are still fairly unconstrained. An important restriction on dark matter models arises from large-scale N -body simulations [2, 3] wh ...
What does a spark chamber detect?
... Positrons These are identical particles to electrons, having the same characteristics. The only difference being that they are positively charged. This is an example of antimatter, and releases gamma radiation when it collides with matter. Quarks One of the fundamental constituents which make up mat ...
... Positrons These are identical particles to electrons, having the same characteristics. The only difference being that they are positively charged. This is an example of antimatter, and releases gamma radiation when it collides with matter. Quarks One of the fundamental constituents which make up mat ...
local - Physics
... he world we live in is a strange and wonderful place. The vast majority of our interactions with objects around us can be described and predicted by relatively simple equations and relations, which have been fully understood for centuries now. The concept of this tactile world is however, a result o ...
... he world we live in is a strange and wonderful place. The vast majority of our interactions with objects around us can be described and predicted by relatively simple equations and relations, which have been fully understood for centuries now. The concept of this tactile world is however, a result o ...
Strangeness production
Strangeness production is a signature and a diagnostic tool of quark–gluon plasma (or QGP) formation and properties. Unlike up and down quarks, from which everyday matter is made, strange quarks are formed in pair-production processes in collisions between constituents of the plasma. The dominant mechanism of production involves gluons only present when matter has become a quark–gluon plasma. When quark–gluon plasma disassembles into hadrons in a breakup process, the high availability of strange antiquarks helps to produce antimatter containing multiple strange quarks, which is otherwise rarely made. Similar considerations are at present made for the heavier charm flavor, which is made at the beginning of the collision process in the first interactions and is only abundant in the high-energy environments of CERN's Large Hadron Collider.