Antiproton




CPT-symmetry puts strong constraints on the relative properties of particles and antiparticles and, therefore, is open to stringent tests. For example, the charges of a proton and antiproton must sum to exactly zero. This equality has been tested to one part in 108. The equality of their masses has also been tested to better than one part in 108. By holding antiprotons in a Penning trap, the equality of the charge-to-mass ratio of protons and antiprotons has been tested to one part in 6×109. The magnetic moment of antiprotons has been measured with error of 8×10−3 nuclear Bohr magnetons, and is found to be equal and opposite to that of a proton.

Comments

Post a Comment

Popular posts from this blog

What Is Whiteboard Animation Video

Whiteboard animation video is the perfect choice for many businesses and marketing campaigns. Whiteboard animation has become hugely popular as companies realise it provides an engaging way of delivering messages and ideas that stand out from other promotional materials. Whiteboard animation is also an excellent way of advertising during festivals, conferences and events, helping build brand recognition with a limited budget. It's no longer just a novelty: Whiteboard animation can be described as: Hand drawing (or hand drawing and animation) on a whiteboard. Whiteboard animation video includes everything from: presentation slide shows, storyboards and demonstrations - all featuring animated video and/or text. This enables you to present information in a more engaging way, with less effort and less time. Whiteboard animation provides a highly interactive way of sharing your information with viewers. Whiteboard animation videos assist in presenting ideas, concepts and goals in a mor
Read more

Stability

Image
Unsolved problem in physics : Are protons fundamentally stable? Or do they decay with a finite lifetime as predicted by some extensions to the standard model? (more unsolved problems in physics) The free proton (a proton not bound to nucleons or electrons) is a stable particle that has not been observed to break down spontaneously to other particles. Free protons are found naturally in a number of situations in which energies or temperatures are high enough to separate them from electrons, for which they have some affinity. Free protons exist in plasmas in which temperatures are too high to allow them to combine with electrons. Free protons of high energy and velocity make up 90% of cosmic rays, which propagate in vacuum for interstellar distances. Free protons are emitted directly from atomic nuclei in some rare types of radioactive decay. Protons also result (along with electrons and antineutrinos) from the radioactive decay of free neutrons, which are unstable. The spontaneous d
Read more

Quarks and the mass of a proton

Image
In quantum chromodynamics, the modern theory of the nuclear force, most of the mass of protons and neutrons is explained by special relativity. The mass of a proton is about 80–100 times greater than the sum of the rest masses of the quarks that make it up, while the gluons have zero rest mass. The extra energy of the quarks and gluons in a region within a proton, as compared to the rest energy of the quarks alone in the QCD vacuum, accounts for almost 99% of the mass. The rest mass of a proton is, thus, the invariant mass of the system of moving quarks and gluons that make up the particle, and, in such systems, even the energy of massless particles is still measured as part of the rest mass of the system. Two terms are used in referring to the mass of the quarks that make up protons: current quark mass refers to the mass of a quark by itself, while constituent quark mass refers to the current quark mass plus the mass of the gluon particle field surrounding the quark.: 285–286 : 150
Read more