Results
The first phase of data using the LHCf detectors was recorded in 2009-2013, as part of the LHC's Run 1. [15] The LHCf results at 7 TeV centre-of-mass energy showed good agreement with theoretical models for forward photon and neutral pion production. However, the results did not agree for the forward neutron production. [16] [17]
LHCf was able to measure how the number of forward photons and neutrons varies with energy at new high energies. The results of the experiment agree with some theoretical models but disagree with other. [18] [19] [20]
The current focus of the LHCf is to look out for neutral kaons and neutral eta mesons, particles that include a strange quark. The theoretical models describing this interaction predict secondary muons, but the predicted numbers disagree with experimental data. The LHCf experiment hopes to resolve the "muon puzzle". [21] [22]
The European Organization for Nuclear Research, known as CERN, is an intergovernmental organization that operates the largest particle physics laboratory in the world. Established in 1954, it is based in Meyrin, western suburb of Geneva, on the France–Switzerland border. It comprises 24 member states. Israel, admitted in 2013, is the only non-European full member. CERN is an official United Nations General Assembly observer.
The Compact Muon Solenoid (CMS) experiment is one of two large general-purpose particle physics detectors built on the Large Hadron Collider (LHC) at CERN in Switzerland and France. The goal of the CMS experiment is to investigate a wide range of physics, including the search for the Higgs boson, extra dimensions, and particles that could make up dark matter.
The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator. It was built by the European Organization for Nuclear Research (CERN) between 1998 and 2008 in collaboration with over 10,000 scientists and hundreds of universities and laboratories across more than 100 countries. It lies in a tunnel 27 kilometres (17 mi) in circumference and as deep as 175 metres (574 ft) beneath the France–Switzerland border near Geneva.
ATLAS is the largest general-purpose particle detector experiment at the Large Hadron Collider (LHC), a particle accelerator at CERN in Switzerland. The experiment is designed to take advantage of the unprecedented energy available at the LHC and observe phenomena that involve highly massive particles which were not observable using earlier lower-energy accelerators. ATLAS was one of the two LHC experiments involved in the discovery of the Higgs boson in July 2012. It was also designed to search for evidence of theories of particle physics beyond the Standard Model.
The Large Electron–Positron Collider (LEP) was one of the largest particle accelerators ever constructed. It was built at CERN, a multi-national centre for research in nuclear and particle physics near Geneva, Switzerland.
The LHCb experiment is a particle physics detector experiment collecting data at the Large Hadron Collider at CERN. LHCb is a specialized b-physics experiment, designed primarily to measure the parameters of CP violation in the interactions of b-hadrons. Such studies can help to explain the matter-antimatter asymmetry of the Universe. The detector is also able to perform measurements of production cross sections, exotic hadron spectroscopy, charm physics and electroweak physics in the forward region. The LHCb collaborators, who built, operate and analyse data from the experiment, are composed of approximately 1650 people from 98 scientific institutes, representing 22 countries. Vincenzo Vagnoni succeeded on July 1, 2023 as spokesperson for the collaboration from Chris Parkes. The experiment is located at point 8 on the LHC tunnel close to Ferney-Voltaire, France just over the border from Geneva. The (small) MoEDAL experiment shares the same cavern.
The ring-imaging Cherenkov, or RICH, detector is a device for identifying the type of an electrically charged subatomic particle of known momentum, that traverses a transparent refractive medium, by measurement of the presence and characteristics of the Cherenkov radiation emitted during that traversal. RICH detectors were first developed in the 1980s and are used in high energy elementary particle-, nuclear- and astro-physics experiments.
ALICE is one of nine detector experiments at the Large Hadron Collider at CERN. The experiment is designed to study the conditions that are thought to have existed immediately after the Big Bang by measuring the properties of quark-gluon plasma.
The TOTEM experiment is one of the nine detector experiments at CERN's Large Hadron Collider. The other eight are: ATLAS, ALICE, CMS, LHCb, LHCf, MoEDAL, FASER and SND@LHC. It shares an interaction point with CMS. The detector aims at measurement of total cross section, elastic scattering, and diffraction processes. The primary instrument of the detector is referred to as a Roman pot. In December 2020, the D0 and TOTEM Collaborations made public the odderon discovery based on a purely data driven approach in a CERN and Fermilab approved preprint that was later published in Physical Review Letters. In this experimental observation, the TOTEM proton-proton data in the region of the diffractive minimum and maximum was extrapolated from 13, 8, 7 and 2.76 TeV to 1.96 TeV and compared this to D0 data at 1.96 TeV in the same t-range giving an odderon significance of 3.4 σ. When combined with TOTEM experimental data at 13 TeV at small scattering angles providing an odderon significance of 3.4 - 4.6 σ, the combination resulted in an odderon significance of at least 5.2 σ.
ZEUS was a particle detector at the HERA particle accelerator at the German national laboratory DESY in Hamburg. It began taking data in 1992 and was operated until HERA was decommissioned in June 2007. The scientific collaboration behind ZEUS consisted of about 400 physicists and technicians from 56 institutes in 17 countries.
The High Luminosity Large Hadron Collider is an upgrade to the Large Hadron Collider, operated by the European Organization for Nuclear Research (CERN), located at the French-Swiss border near Geneva. From 2011 to 2020, the project was led by Lucio Rossi. In 2020, the lead role was taken up by Oliver Brüning.
The NA62 experiment is a fixed-target particle physics experiment in the North Area of the SPS accelerator at CERN. The experiment was approved in February 2007. Data taking began in 2015, and the experiment is expected to become the first in the world to probe the decays of the charged kaon with probabilities down to 10−12. The experiment's spokesperson is Giuseppe Ruggiero. The collaboration involves 308 participants from 33 institutions and 16 countries around the world.
Sir Tejinder Singh Virdee,, is a Kenyan-born British experimental particle physicist and Professor of Physics at Imperial College London. He is best known for originating the concept of the Compact Muon Solenoid (CMS) with a few other colleagues and has been referred to as one of the 'founding fathers' of the project. CMS is a world-wide collaboration which started in 1991 and now has over 3500 participants from 50 countries.
FASER is one of the nine particle physics experiments in 2022 at the Large Hadron Collider at CERN. It is designed to both search for new light and weakly coupled elementary particles, and to detect and study the interactions of high-energy collider neutrinos. In 2023, FASER and SND@LHC reported the first observation of collider neutrinos.
Teresa Rodrigo Anoro was a Spanish scientist who worked in particle physics. She worked at CERN, Fermilab and the Instituto de Física de Cantabria and was professor at the University of Cantabria. Whilst at CERN, Rodrigo worked on the Compact Muon Solenoid and research for the Higgs boson.
Bradley Cox is an American physicist, academic and researcher. He is a Professor of Physics and the founder of the High Energy Physics Group at the University of Virginia.
A fixed-target experiment in particle physics is an experiment in which a beam of accelerated particles is collided with a stationary target. The moving beam consists of charged particles such as electrons or protons and is accelerated to relativistic speed. The fixed target can be a solid block or a liquid or a gaseous medium. These experiments are distinct from the collider-type experiments in which two moving particle beams are accelerated and collided. The famous Rutherford gold foil experiment, performed between 1908 and 1913, was one of the first fixed-target experiments, in which the alpha particles were targeted at a thin gold foil.
James Lewis Pinfold is a British-Canadian physicist, specializing in particle physics.
The Underground Area 7 (UA7) experiment was a high-energy physics experiment at the Proton-Antiproton Collider, a modification of the Super Proton Synchrotron (SPS), at CERN. The purpose of the experiment was to measure the invariant cross section of photons and neutral pions (π0) emitted close to zero degrees, by using silicon shower detectors. The experiment data taking ran from 1985 to 1986, and the final analysis was completed in 1996.
The Underground Area 9 (UA9) experiment is a high-energy physics experiment using particle beams from the Super Proton Synchrotron (SPS), at CERN. The purpose of the experiment is to investigate how using tiny bent crystals could allow the collimation of beams in modern hadron colliders to improve. UA9 was approved in 2008, and is in-progress as of 2013.
