New Experiments with Antiprotons

Fermilab operates the world's most intense antiproton source. Newly proposed experiments can use those antiprotons either parasitically during Tevatron Collider running or after the Tevatron Collider finishes in about 2011. For example, the annihilation of 8 GeV antiprotons might make the world's most intense source of tagged D^0 mesons, and thus the best near-term opportunity to study charm mixing and, via CP violation, to search for new physics. Other potential measurements include sensitive studies of hyperons and of the mysterious X, Y, and Z states. Production of antihydrogen in flight can be used for first searches for antihydrogen CPT violation. With antiproton deceleration to low energy, an experiment using a Penning trap and an atom interferometer could make the world's first measurement of the gravitational force on antimatter.Comment: Prepared for the Proceedings of the 4th International Symposium on Symmetries in Subatomic Physics (SSP2009), June 2-5, 2009, Department of Physics, National Taiwan University, Taipei, Taiwa

Patentable Subject [Anti]matter

The statements, The laws of nature, the principles of nature, the fundamental truths, etc., are not patentable, have been oft repeated but seldom understandingly used. They have led to misunderstanding and much confusion, not limited to members of the bar. In fact, the words... are all words of broad and also elastic meaning and are frequently used carelessly and without any attempt at refined distinctions

Future Prospects for Hadron Physics at PANDA

The PANDA experiment at the new FAIR facility will be the major hadron physics experiment at the end of this decade. It has an ambitious far-reaching physics program that spans the most fascinating topics that are emerging in contemporary hadron physics. The universality of the antiproton annihilation process, with either protons or nuclei as targets, allows physicists to address questions like the structure of glueballs and hybrids; to clarify the nature of the X, Y and Z states; to investigate electromagnetic channels in order to measure form factors of the nucleon; and to provide theory with input with respect to non-perturbative aspects of QCD. The possibility to use different nuclear targets opens the window for charm physics with nuclei or for color transparency studies, as well as for an intensive hypernuclear physics program. Previous experimental experience has clearly demonstrated that the key to success lies in high levels of precision complemented with sophisticated analysis methods, only possible with high statistics in the data set. However, since this puts many critical demands on the detector, PANDA's design has incorporated cutting-edge detector technologies that in some cases have surpassed even the requirements for LHC experiments.Comment: 70 pages, 54 figures, review articl

Measurement of interaction between antiprotons

One of the primary goals of nuclear physics is to understand the force between nucleons, which is a necessary step for understanding the structure of nuclei and how nuclei interact with each other. Rutherford discovered the atomic nucleus in 1911, and the large body of knowledge about the nuclear force since acquired was derived from studies made on nucleons or nuclei. Although antinuclei up to antihelium-4 have been discovered and their masses measured, we have no direct knowledge of the nuclear force between antinucleons. Here, we study antiproton pair correlations among data taken by the STAR experiment at the Relativistic Heavy Ion Collider and show that the force between two antiprotons is attractive. In addition, we report two key parameters that characterize the corresponding strong interaction: namely, the scattering length (f0) and effective range (d0). As direct information on the interaction between two antiprotons, one of the simplest systems of antinucleons, our result provides a fundamental ingredient for understanding the structure of more complex antinuclei and their properties.Comment: 25 pages, 4 figures. Submitted to Nature. Under media embarg

Anitproton-matter interactions in antiproton applications

By virtue of the highly energetic particles released when they annihilate in matter, antiprotons have a variety of potentially important applications. Among others, these include remote 3-D density and composition imaging of the human body and also of thick, dense materials, cancer therapy, and spacecraft propulsion. Except for spacecraft propulsion, the required numbers of low energy antiprotons can be produced, stored, and transported through reliance on current or near term technology. Paramount to these applications and to fundamental research involving antiprotons is knowledge of how antiprotons interact with matter. The basic annihilation process is fairly well understood, but the antiproton annihilation and energy loss rates in matter depend in complex ways on a number of atomic processes. The rates, and the corresponding cross sections, were measured or are accurately predictable only for limited combinations of antiproton kinetic energy and material species

Indirect Dark Matter Signals from EGRET and PAMELA compared

Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. The excess of diffuse Galactic Gamma Rays from EGRET shows all the features expected from DMA. The new precise measurements of the antiproton and positron fractions from PAMELA are compared with the EGRET excess. It is shown that the charged particles are strongly dependent on the propagation model used. The usual propagation models with isotropic propagation models are incompatible with the recently observed convection in our Galaxy. Convection leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space. It is shown that such anisotropic propagation models including convection prefer a contribution from DMA for the antiprotons, but the rise in the positron fraction, as observed by PAMELA, is incompatible with DMA, if compared with the EGRET excess. A rise in the positron/electron ratio is expected, if the observed rise in the proton/electron ratio is carefully fitted in a propagation model, although the rise is slightly larger than expected, so additional local sources may contribute as well within the limited accuracy of the data.Comment: 10 pages, 4 figures, Contributed paper to the Eighth UCLA Symposium: Sources and Detection of Dark Matter and Dark Energy in the Univers

On Phenomenology of Complex Scientific Systems

Performance evolution of a number of complex scientific and technical systems demonstrate exponential progress with time exp(+t/C) . The speed of progress C - a measure of difficulty and complexity - is analyzed for high energy elementary particle colliders, astrophysical searches for galaxies and exoplanets, protein structure determination and compared with computers and thermonuclear fusion reactors. An explanation of the characteristic exponential progress is offered.Comment: 14 pages, 11 Figs, 2 Tables v2 - Fig.10 and one reference added (on peak laser power