Related Experiment Video
Updated: May 7, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 16, 2013
Rho(0) meson production in the pp-->pppi(+)pi(-) reaction at 3.67 GeV/c
F Balestra1, Y Bedfer, R Bertini
1Dipartimento di Fisica A. Avogadro and INFN, Torino I-10125, Italy.
Physical Review Letters
|August 23, 2002
Summary
Measurements of exclusive proton-proton to proton-proton rho meson production at 3.67 GeV/c reveal a low cross section and anisotropic production. These findings offer insights into meson dynamics in particle collisions.
Area of Science:
- High-energy particle physics
- Nuclear physics
- Quantum chromodynamics
Background:
- Understanding meson production mechanisms is crucial for interpreting particle and heavy-ion collisions.
- Previous models often used higher cross sections for meson production, necessitating experimental validation.
Purpose of the Study:
- To measure total and differential cross sections for the exclusive reaction pp-->pp rho.
- To compare experimental cross sections with theoretical models used in heavy-ion collisions.
- To investigate the production mechanism and angular distribution of rho(0) mesons.
Main Methods:
- The experiment utilized a proton beam at 3.67 GeV/c.
- The exclusive reaction pp-->pp rho was observed through the pi(+)pi(-) decay channel.
- Total and differential cross sections were meticulously measured.
Main Results:
- The total meson production cross section was determined to be (23.4+/-0.8+/-8) mu b.
- This measured cross section is significantly lower than values typically used in heavy-ion collision models.
- Differential cross sections showed a strong anisotropy in rho(0) meson production, approximated by cos(theta(CM)(rho)).
Conclusions:
- The study provides crucial experimental data on exclusive meson production in proton-proton interactions.
- The low measured cross section suggests that current models may overestimate meson production in certain collision scenarios.
- The observed anisotropy offers insights into the dynamics and underlying physics of rho(0) meson production.
Related Concept Videos
03:23Types of Radioactivity
The most common types of radioactivity are α decay, β decay, γ decay, neutron emission, and electron capture.
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
Alpha (α) decay is the emission of an α particle from the nucleus. For example, polonium-210 undergoes α decay:
03:20Nuclear Transmutation
Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with another particle. The first manmade nucleus was produced in Ernest Rutherford’s laboratory in 1919 by a transmutation reaction, the bombardment of one type of nuclei with other nuclei or with neutrons. Rutherford bombarded nitrogen-14 atoms with high-speed α particles from a natural radioactive isotope of radium and observed protons being...
01:13¹H NMR: Complex Splitting
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
01:21Chemical Ionization (CI) Mass Spectrometry
The molecular ion peak of a molecule in the mass spectrum provides vital information for molecular identification. However, conventional electron impact ionization can lead to the rapid dissociation of some molecular ions before they reach the detector. A milder ionization method is required to increase the lifetime of such ionized analyte molecules. Chemical ionization (CI) is a gas-phase protonation reaction useful for mass-analyzing analyte molecules that are easily protonated to yield the...
01:14Atomic Nuclei: Nuclear Spin State Population Distribution
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
01:19Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
In inductively coupled plasma–mass spectrometry (ICP–MS), an inductively coupled plasma (ICP) torch is used as an atomizer and ionizer. Solid samples are dissolved and volatilized before being introduced into the high-temperature argon plasma, while solution samples are nebulized and passed through the high-temperature argon plasma. Plasma dissociates the analytes and ionizes their component atoms to form a mixture of positive ions and molecular species. The positive ions are then passed on to...