Recipe for muon pair creation, in theory

January 19, 2016, Springer
Recipe for muon pair creation, in theory

A true-muonium only lives for two microseconds. These atoms are made up one positively and one negatively charged elementary particle, also known as muons. Although they have yet to be observed experimentally, a Japanese theoretical physicist has come up with new ways of creating them, in principle, via particle collisions. The first method involves colliding a negatively charged muon and a muonium atom made up of a positive muon and an electron. The second involves colliding a positively charged muon and a muonic hydrogen atom made up of a proton and a negative muon. The author found that the second option offers the most promising advances for muonium detection. These findings have been published in EPJ D by Kazuhiro Sakimoto from the Japan Aerospace Exploration Agency in Kanagawa.

In this study, Sakimoto performs theoretical calculations using the semi-classical method for describing the dynamics dominated by the first process. In such cases, the distance between the negative and positive muons is treated as a classical variable and the remaining degrees of freedom are described by quantum mechanics.

Subsequently, the muon exchange dynamics in the second approach involving a positively charged muon colliding with a muonic hydrogen rely on simulations relying on the so-called classical-trajectory Monte-Carlo(CTMC) method. The degrees of freedom in such instances are described using classical mechanics.

This theoretical study is relevant for experiments with low-energy muon beams as part of the Ultra Slow Muon project at J-PARC MUSE. Furthermore, analysing muoniums via spectroscopic methods can be useful to perform high-precision tests related to a theory called Quantum ElectroDynamics (QED). The precision of previous measurements based on was limited by uncertainties related to the internal structure of the inside its nucleus. This matters for a particular type of measurement of the proton size, called 'proton radius puzzle', that has remained unsolved over the past five years. So far, two different measuring techniques have yielded two different measures for the proton size.

Explore further: Proton radius puzzle may be solved by quantum gravity

More information: Kazuhiro Sakimoto. Theoretical study of true-muonium μ + μ − formation in muon collision processes μ − + μ +e− and μ + + pμ −, The European Physical Journal D (2015). DOI: 10.1140/epjd/e2015-60427-6

Related Stories

Proton radius puzzle may be solved by quantum gravity

November 26, 2013

(Phys.org) —Officially, the radius of a proton is 0.88 ± 0.01 femtometers (fm, or 10-15 m). Researchers attained that value using two methods: first, by measuring the proton's energy levels using hydrogen spectroscopy, ...

Physicists confirm surprisingly small proton radius

January 24, 2013

International team of physicists confirms surprisingly small proton radius with laser spectroscopy of exotic hydrogen. The initial results puzzled the world three years ago: the size of the proton (to be precise, its charge ...

Muons help understand mechanism behind hydrogen storage

November 18, 2014

It is ever more necessary to find alternative ways to store energy. Energy storage is required when energy is supplied intermittently, as for instance for wind power, or for mobile applications like cars. Hydrogen is a promising ...

Anti-hydrogen origin revealed by collision simulation

January 18, 2016

Antihydrogen is a particular kind of atom, made up of the antiparticle of an electron—a positron—and the antiparticle of a proton—an antiproton. Scientists hope that studying the formation of anti hydrogen will ultimately ...

Particle physics: 'Honey, I shrunk the proton'

July 7, 2010

Scientists lobbed a bombshell into the world of sub-atomic theory on Wednesday by reporting that a primary building block of the visible Universe, the proton, is smaller than previously thought.

Recommended for you

New quantum memory stores information for hours

February 22, 2018

Storing information in a quantum memory system is a difficult challenge, as the data is usually quickly lost. At TU Wien, ultra-long storage times have now been achieved using tiny diamonds.

MEMS chips get metatlenses

February 20, 2018

Lens technologies have advanced across all scales, from digital cameras and high bandwidth in fiber optics to the LIGO lab instruments. Now, a new lens technology that could be produced using standard computer-chip technology ...

Reaching new heights in laser-accelerated ion energy

February 20, 2018

A laser-driven ion acceleration scheme, developed in research led at the University of Strathclyde, could lead to compact ion sources for established and innovative applications in science, medicine and industry.

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

axemaster
not rated yet Jan 19, 2016
I guess it's a mark of having done way too much science, but it's funny that when I hear "this exotic particle only lives for 2µs", I think "Wow that's a really long time!".
Jeffhans1
not rated yet Jan 19, 2016
I'm just trying to imagine what the universe would look like if this was a valid alternate path for matter to create complex structures and perhaps even lifeforms. I know that it all eventually returns to a neutral energy state, but the moments in between literally mean everything to us.
phxmarker
not rated yet Feb 08, 2016
Here's a solution to the proton radius puzzle: https://drive.goo...mp;pli=1

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.