Sunday, November 20, 2011

Energy Boost From Shock Front

Main Components of CNGS
A 400 GeV/c proton beam is extracted from the SPS in 10.5 microsecond short pulses of 2.4x1013 protons per pulse. The proton beam is transported through the transfer line TT41 to the CNGS target T40. The target consists of a series of graphite rods, which are cooled by a recirculated helium flow. Secondary pions and kaons of positive charge produced in the target are focused into a parallel beam by a system of two pulsed magnetic lenses, called horn and reflector. A 1 km long evacuated decay pipe allows the pions and kaons to decay into their daughter particles - of interest here is mainly the decay into muon-neutrinos and muons. The remaining hadrons (protons, pions, kaons) are absorbed in an iron beam dump with a graphite core. The muons are monitored in two sets of detectors downstream of the dump. Further downstream, the muons are absorbed in the rock while the neutrinos continue their travel towards Gran Sasso.microsecond short pulses of 2.4x1013 protons per
 For me it has been an interesting journey in trying to understand the full context of a event in space sending information through out the cosmos in ways that are not limited to the matter configurations that would affect signals of those events.

In astrophysics, the most widely discussed mechanism of particle acceleration is the first-order Fermi process operating at collisionless shocks. It is based on the idea that particles undergo stochastic elastic scatterings both upstream and downstream of the shock front. This causes particles to wander across the shock repeatedly. On each crossing, they receive an energy boost as a result of the relative motion of the upstream and downstream plasmas. At non-relativistic shocks, scattering causes particles to diffuse in space, and the mechanism, termed "diffusive shock acceleration," is widely thought to be responsible for the acceleration of cosmic rays in supernova remnants. At relativistic shocks, the transport process is not spatial diffusion, but the first-order Fermi mechanism operates nevertheless (for reviews, see Kirk & Duffy 1999; Hillas 2005). In fact, the first ab initio demonstrations of this process using particle-in-cell (PIC) simulations have recently been presented for the relativistic case (Spitkovsky 2008b; Martins et al. 2009; Sironi & Spitkovsky 2009).
Several factors, such as the lifetime of the shock front or its spatial extent, can limit the energy to which particles can be accelerated in this process. However, even in the absence of these, acceleration will ultimately cease when the radiative energy losses that are inevitably associated with the scattering process overwhelm the energy gains obtained upon crossing the shock. Exactly when this happens depends on the details of the scattering process. See: RADIATIVE SIGNATURES OF RELATIVISTIC SHOCKS

So in soliton expressions while trying to find such an example here in the blog does not seem to be offering itself in the animations of the boat traveling down the channel we are so familiar with that for me this was the idea of the experimental processes unfolding at LHC. The collision point creates shock waves\particle sprays as Jets?


Soliton


Solitary wave in a laboratory wave channel.
In mathematics and physics, a soliton is a self-reinforcing solitary wave (a wave packet or pulse) that maintains its shape while it travels at constant speed. Solitons are caused by a cancellation of nonlinear and dispersive effects in the medium. (The term "dispersive effects" refers to a property of certain systems where the speed of the waves varies according to frequency.) Solitons arise as the solutions of a widespread class of weakly nonlinear dispersive partial differential equations describing physical systems. The soliton phenomenon was first described by John Scott Russell (1808–1882) who observed a solitary wave in the Union Canal in Scotland. He reproduced the phenomenon in a wave tank and named it the "Wave of Translation".

So in a sense the shock front\horn for me in respect of Gran Sasso is the idea that such a front becomes a dispersive element in medium expression of earth to know that such densities in earth have a means by which we can measure relativist interpretations as assign toward density determinations in the earth.  Yet,  there are things not held to this distinction so know that they move on past such targets so as to show cosmological considerations are just as relevant today as they are while we set up the experimental avenues toward identifying this relationship here on earth.

 For more than a decade, scientists have seen evidence that the three known types of neutrinos can morph into each other. Experiments have found that muon neutrinos disappear, with some of the best measurements provided by the MINOS experiment. Scientists think that a large fraction of these muon neutrinos transform into tau neutrinos, which so far have been very hard to detect, and they suspect that a tiny fraction transform into electron neutrinos. See: Fermilab experiment weighs in on neutrino mystery

When looking out at the universe such perspective do not hold relevant for those not looking past the real toward the abstract? To understand the distance measure of binary star of Taylor and Hulse,  such signals need to be understood in relation to what is transmitted out into the cosmos? How are we measuring that distance? For some who are even more abstractedly gifted they may see the waves generated in gravitational expression. So this becomes a means which which to ask if the binary stars are getting closer then how is this distance measured? You see?


Measurement of the neutrino velocity with the OPERA detectorin the CNGS beam 





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