PERDaix (Proton Electron Radiation Detector Aix-la-Chapelle) is a novel, small and light weight magnetic spectrometer to measure the charge and mass dependent solar modulation periodically for deeper understanding of cosmic rays. [1] For a better understanding of sources and acceleration of cosmic particles direct measurements of cosmic rays are necessary. Also for a better understanding of the solar modulation which is expected to follow the 22-year solar cycle, time dependent measurements are needed. [2] PERDaix is a newly designed detector which is constructed by the Department of Physics 1b, RWTH Aachen University. Being proposed to the German Space Agency in November 2009 for a participation in the BEXUS Program (Rocket and Balloon Experiments for University Students) after a first canceled flight attempt in October 2010 the actual flight took place as a post-BEXUS-campaign flight opportunity in November 2010.
The detector is able to measure charged particles in the energy range of 0.5 GeV to 5 GeV. PERDaix uses a time of flight system, a scintillating fiber tracker with silicon photomultiplier (SiPM) readout, and a transition radiation detector in combination with a permanent magnet to measure particle fluxes. [3] The BEXUS balloons are launched at Esrange Space Center near Kiruna, Sweden. In November 2010 PERDaix reached a top altitude of 33.3 km at which it kept floating for 1.5 hours.
The time of flight system (TOF) is the upper- and lowermost layer of the detector. It consists of scintillators with an SiPM readout. It is used as a trigger signal and to discriminate against particles entering the detector from below. With a design time resolution of approximately 300 picoseconds (ps) it can be used to distinguish between positrons and electrons in the momentum range below 1 GeV. Protons can be distinguished from positrons for momenta below 1 GeV if their velocity is lower than β = 1. [4]
Perdaix will make use of a scintillating fiber tracking detector made up from 250 μm thin scintillating polystyrene fibers that emit light when traversed by a charged particle. The scintillating fibers are read out by silicon photomultiplier (SiPM) arrays which are structured semi-conductor photon detectors that offer high photon efficiencies of 50%, a high gain of 10^6 electrons / photon and that are very compact in size. One silicon photomultiplier array is 1.1mm by 8.0mm in size and has 32 channels. Twenty 32mm wide and 300mm long fiber modules are arranged in four layers around a hollow cylindrical permanent magnet array.
The permanent magnet array is constructed as a Halbach-Ring and weighs 8 kg and produces a very high magnetic field of ~0.26 Tesla (T) inside an 80mm high and 213mm diameter magnet cylinder while producing only a negligible magnetic field outside the cylinder.
Underneath the lowest tracker layer a transition radiation detector (TRD) is installed. The TRD detects transition radiation of relativistic particles with a Lorentz factor γ exceeding ≈ 1000. Particles crossing the interface of two media with different dielectric constant produce transition radiation. The energy loss at a boundary is proportional to the relativistic gamma factor. A significant amount of TR is produced for a gamma greater than 1000. The gamma factor of protons is, up to a momentum of 5GeV, still in the order of 10, whereas the positron's gamma is greater than 1000, starting at 0.5GeV momentum.
The detector is made up of 256 6mm thick straw tubes out of a 72 um thin multilayer aluminium-kapton foil, filled with an 80/20 mixture of xenon (Xe) and carbon dioxide (CO2). It is used to measure the x-ray transition radiation produced by electrons in eight 20mm thick layers of an irregular fleece radiator. This leads to more than 100 material interfaces per radiator layer.
Due to strong winds the launch campaign in October 2010 had to be canceled without a BEXUS-11 flight at first. Thanks to the support of German Space Agency (DLR) and Esrange a second flight opportunity was provided in late November 2010. On 23 November a 100 000 m³ helium balloon was launched from Esrange carrying a payload of 334 kg containing the BEXUS student experiments including the PERDaix detector.
A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillating material, and detecting the resultant light pulses.
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.
A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate. Sometimes, the excited state is metastable, so the relaxation back down from the excited state to lower states is delayed. The process then corresponds to one of two phenomena: delayed fluorescence or phosphorescence. The correspondence depends on the type of transition and hence the wavelength of the emitted optical photon.
The Compton Gamma Ray Observatory (CGRO) was a space observatory detecting photons with energies from 20 keV to 30 GeV, in Earth orbit from 1991 to 2000. The observatory featured four main telescopes in one spacecraft, covering X-rays and gamma rays, including various specialized sub-instruments and detectors. Following 14 years of effort, the observatory was launched from Space Shuttle Atlantis during STS-37 on April 5, 1991, and operated until its deorbit on June 4, 2000. It was deployed in low Earth orbit at 450 km (280 mi) to avoid the Van Allen radiation belt. It was the heaviest astrophysical payload ever flown at that time at 16,300 kilograms (35,900 lb).
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 Cowan–Reines neutrino experiment was conducted by physicists Clyde Cowan and Frederick Reines in 1956. The experiment confirmed the existence of neutrinos. Neutrinos, subatomic particles with no electric charge and very small mass, had been conjectured to be an essential particle in beta decay processes in the 1930s. With neither mass nor charge, such particles appeared to be impossible to detect. The experiment exploited a huge flux of electron antineutrinos emanating from a nearby nuclear reactor and a detector consisting of large tanks of water. Neutrino interactions with the protons of the water were observed, verifying the existence and basic properties of this particle for the first time.
A gamma camera (γ-camera), also called a scintillation camera or Anger camera, is a device used to image gamma radiation emitting radioisotopes, a technique known as scintigraphy. The applications of scintigraphy include early drug development and nuclear medical imaging to view and analyse images of the human body or the distribution of medically injected, inhaled, or ingested radionuclides emitting gamma rays.
Explorer 11 was a NASA satellite that carried the first space-borne gamma-ray telescope. This marked the beginning of space gamma-ray astronomy. Launched on 27 April 1961 by a Juno II, the satellite returned data until 17 November 1961, when power supply problems ended the science mission. During the spacecraft's seven-month lifespan it detected twenty-two events from gamma-rays and approximately 22,000 events from cosmic radiation.
HERA was a particle accelerator at DESY in Hamburg. It was operated from 1992 to 30 June 2007. At HERA, electrons or positrons were brought to collision with protons at a center-of-mass energy of 320 GeV. HERA was used mainly to study the structure of protons and the properties of quarks, laying the foundation for much of the science done at the Large Hadron Collider (LHC) at the CERN particle physics laboratory today. HERA is the only lepton–proton collider in the world to date and was on the energy frontier in certain regions of the kinematic range.
Air showers are extensive cascades of subatomic particles and ionized nuclei, produced in the atmosphere when a primary cosmic ray enters the atmosphere. Particles of cosmic radiation can be protons, nuclei, electrons, photons, or (rarely) positrons. Upon entering the atmosphere, they interact with molecules and initiate a particle cascade that lasts for several generations, until the energy of the primary particle is fully converted. If the primary particle is a hadron, mostly light mesons like pions and kaons are produced in the first interactions, which then fuel a hadronic shower component that produces shower particles mostly through pion decay. Primary photons and electrons, on the other hand, produce mainly electromagnetic showers. Depending on the energy of the primary particle, the detectable size of the shower can reach several kilometers in diameter.
Gamma-ray spectroscopy is the qualitative study of the energy spectra of gamma-ray sources, such as in the nuclear industry, geochemical investigation, and astrophysics. Gamma-ray spectrometry, on the other hand, is the method used to acquire a quantitative spectrum measurement.
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 DØ experiment was a worldwide collaboration of scientists conducting research on the fundamental nature of matter. DØ was one of two major experiments located at the Tevatron Collider at Fermilab in Batavia, Illinois. The Tevatron was the world's highest-energy accelerator from 1983 until 2009, when its energy was surpassed by the Large Hadron Collider. The DØ experiment stopped taking data in 2011, when the Tevatron shut down, but data analysis is still ongoing. The DØ detector is preserved in Fermilab's DØ Assembly Building as part of a historical exhibit for public tours.
IACT is a device or method to detect very-high-energy gamma ray photons in the photon energy range of 50 GeV to 50 TeV.
Neutron detection is the effective detection of neutrons entering a well-positioned detector. There are two key aspects to effective neutron detection: hardware and software. Detection hardware refers to the kind of neutron detector used and to the electronics used in the detection setup. Further, the hardware setup also defines key experimental parameters, such as source-detector distance, solid angle and detector shielding. Detection software consists of analysis tools that perform tasks such as graphical analysis to measure the number and energies of neutrons striking the detector.
A neutrino detector is a physics apparatus which is designed to study neutrinos. Because neutrinos only weakly interact with other particles of matter, neutrino detectors must be very large to detect a significant number of neutrinos. Neutrino detectors are often built underground, to isolate the detector from cosmic rays and other background radiation. The field of neutrino astronomy is still very much in its infancy – the only confirmed extraterrestrial sources as of 2018 are the Sun and the supernova 1987A in the nearby Large Magellanic Cloud. Another likely source is the blazar TXS 0506+056 about 3.7 billion light years away. Neutrino observatories will "give astronomers fresh eyes with which to study the universe".
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.
The ZEPLIN-III dark matter experiment attempted to detect galactic WIMPs using a 12 kg liquid xenon target. It operated from 2006 to 2011 at the Boulby Underground Laboratory in Loftus, North Yorkshire. This was the last in a series of xenon-based experiments in the ZEPLIN programme pursued originally by the UK Dark Matter Collaboration (UKDMC). The ZEPLIN-III project was led by Imperial College London and also included the Rutherford Appleton Laboratory and the University of Edinburgh in the UK, as well as LIP-Coimbra in Portugal and ITEP-Moscow in Russia. It ruled out cross-sections for elastic scattering of WIMPs off nucleons above 3.9 × 10−8 pb from the two science runs conducted at Boulby.
The High Altitude Water Cherenkov Experiment or High Altitude Water Cherenkov Observatory is a gamma-ray and cosmic ray observatory located on the flanks of the Sierra Negra volcano in the Mexican state of Puebla at an altitude of 4100 meters, at 18°59′41″N97°18′30.6″W. HAWC is the successor to the Milagro gamma-ray observatory in New Mexico, which was also a gamma-ray observatory based around the principle of detecting gamma-rays indirectly using the water Cherenkov method.
The Beijing Spectrometer III is a particle physics experiment at the Beijing Electron–Positron Collider II at the Institute of High Energy Physics (IHEP). It is designed to study the physics of charm, charmonium, and light hadron decays. It also performs studies of the tau lepton, tests of QCD, and searches for physics beyond the Standard Model. The experiment started collecting data in the summer of 2008.