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Topic Review
Jet Flavour Tagging
Jet Flavour Tagging briefly describes the main algorithms used to reconstruct heavy-flavour jets. Jet Substructure and Deep Tagging focuses on the identification of heavy-particle decay in boosted jets. These so-called tagger algorithms have a relevant role in physics studies since they allow researchers to successfully reconstruct and identify the particles that caused the jet and, in some cases, allow analyses that would otherwise be unfeasible.
  • 570
  • 09 Nov 2022
Topic Review
Channelling
Channelling is the process that constrains the path of a charged particle in a crystalline solid. Many physical phenomena can occur when a charged particle is incident upon a solid target, e.g., elastic scattering, inelastic energy-loss processes, secondary-electron emission, electromagnetic radiation, nuclear reactions, etc. All of these processes have cross sections which depend on the impact parameters involved in collisions with individual target atoms. When the target material is homogeneous and isotropic, the impact-parameter distribution is independent of the orientation of the momentum of the particle and interaction processes are also orientation-independent. When the target material is monocrystalline, the yields of physical processes are very strongly dependent on the orientation of the momentum of the particle relative to the crystalline axes or planes. Or in other words, the stopping power of the particle is much lower in certain directions than others. This effect is commonly called the "channelling" effect. It is related to other orientation-dependent effects, such as particle diffraction. These relationships will be discussed in detail later.
  • 570
  • 29 Nov 2022
Topic Review
Radiography of Cultural Objects
The radiography of cultural objects is the use of radiography to understand intrinsic details about objects. Most commonly this involves X-rays of paintings to reveal underdrawing, pentimenti alterations in the course of painting or by later restorers, and sometimes previous paintings on the support. Many pigments such as lead white show well in radiographs. X-ray spectromicroscopy has also been used to analyse the reactions of pigments in paintings. For example, in analysing colour degradation in the paintings of van Gogh. These processes can reveal various details about objects that are not visible to the naked eye. This information, which includes structural elements, aids conservators as they assess object condition and consider treatment plans. For three dimensional objects, the computed tomography (CT) has become a common tool, which when combined with analysis can, for example, "digitally unroll" or unfold and make possible the reading of fragile scrolls, books, or sealed correspondence.
  • 557
  • 10 Oct 2022
Topic Review
Virtual Breakdown Mechanism
The Virtual breakdown mechanism is a concept in the field of electrochemistry. In electrochemical reactions, when the cathode and the anode are close enough to each other (i.e., so-called "nanogap electrochemical cells"), the double layer the regions from the two electrodes is overlapped, forming a large electric field uniformly distributed inside the entire electrode gap. Such high electric fields can significantly enhance the ion migration inside bulk solutions and thus increase the entire reaction rate, akin to the "breakdown" of the reactant(s). However, it is fundamentally different from the traditional "breakdown". The Virtual breakdown mechanism was discovered in 2017 when researchers studied pure water electrolysis based on deep-sub-Debye-length nanogap electrochemical cells. Furthermore, researchers found the relation of the gap distance between cathodes and anodes to the performance of electrochemical reactions.
  • 534
  • 10 Nov 2022
Topic Review
Beyond Special Relativity
There are two different ways in which one can go beyond the kinematics of Special Relativity (SR). One can consider adding to the Standard Model (SM) Lagrangian new terms that violate Lorentz Invariance (LIV). In case one wants to preserve the relativistic invariance, one should modify the transformations between inertial frames and accordingly modify the special relativistic kinematics; this is what is called Doubly/Deformed Special Relativity (DSR). 
  • 529
  • 13 Jul 2022
Topic Review
Laboratory B in Sunguľ
Laboratory B in Sunguľ was one of the laboratories under the 9th Chief Directorate of the NKVD (MVD after 1946) that contributed to the Soviet atomic bomb project. It was created in 1946 and closed in 1955, when some of its personnel were merged with the second Soviet nuclear design and assembly facility. It was run as a sharashka – a secret scientific facility run as a prison. Laboratory B employed German scientists from 1947 to 1953. It had two scientific divisions, radiochemistry and radiobiophysics; the latter was headed by the world-renowned geneticist N. V. Timofeev-Resovskij. For two years, the renowned German chemist, Nikolaus Riehl was the scientific director.
  • 517
  • 25 Oct 2022
Topic Review
Bioelectromagnetics
Bioelectromagnetics, also known as bioelectromagnetism, is the study of the interaction between electromagnetic fields and biological entities. Areas of study include electrical or electromagnetic fields produced by living cells, tissues or organisms, including bioluminescent bacteria; for example, the cell membrane potential and the electric currents that flow in nerves and muscles, as a result of action potentials. Others include animal navigation utilizing the geomagnetic field; the effects of man-made sources of electromagnetic fields like mobile phones; and developing new therapies to treat various conditions. The term can also refer to the ability of living cells, tissues, and organisms to produce electrical fields and the response of cells to electromagnetic fields.
  • 517
  • 27 Oct 2022
Topic Review
Progress on Advanced Photocathodes for Superconducting RF Guns
The superconducting radio frequency photoinjector (SC RF gun or SRF gun) combines the principle of a photoelectron gun with the application of a superconducting (SC) accelerating cavity. The photocathode is located very close to the SC cavity or directly in contact with it. Since the first concept was proposed by H. Chaloupka in the 1988 EPAC, the SRF gun has been proved to be a successful technology producing high brightness and a high-current beam, which is required by continuous-wave (CW) free electron lasers (FELs) and energy recovery linac (ERL) facilities.
  • 503
  • 29 Aug 2022
Topic Review
Raman Spectroelectrochemistry
Raman spectroelectrochemistry (Raman-SEC) is a technique that studies the inelastic scattering or Raman scattering of monochromatic light related to chemical compounds involved in an electrode process. This technique provides information about vibrational energy transitions of molecules, using a monochromatic light source, usually from a laser that belongs to the UV, Vis or NIR region. Raman spectroelectrochemistry provides specific information about structural changes, composition and orientation of the molecules on the electrode surface involved in an electrochemical reaction, being the Raman spectra registered a real fingerprint of the compounds. When a monochromatic light beam samples the electrode/solution interface, most of the photons are scattered elastically, with the same energy than the incident light. However, a small fraction is scattered inelastically, being the energy of the laser photons shifted up or down. When the scattering is elastic, the phenomenon is denoted as Rayleigh scattering, while when it is inelastic it is called Raman scattering. Raman spectroscopy combined with electrochemical techniques, makes Raman spectroelectrochemistry a powerful technique in the identification, characterization and quantification of molecules. The main advantage of Raman spectroelectrochemistry is that it is not limited to the selected solvent, and aqueous and organic solutions can be used. However, the main disadvantage is the intrinsic low Raman signal intensity. Different methods as well as new substrates were developed to improve the sensitivity and selectivity of this multirresponse technique.
  • 490
  • 14 Oct 2022
Topic Review
BatteryMAX (Idle Detection)
BatteryMAX is an idle detection system used for computer power management under operating system control developed at Digital Research, Inc.'s European Development Centre (EDC) in Hungerford, UK. It was created to address the new genre of portable personal computers (laptops) which ran from battery power. As such, it was also an integral part of Novell's PalmDOS 1.0 operating system tailored for early palmtops in 1992.
  • 483
  • 24 Nov 2022
Topic Review
Photoelectrochemistry
Photoelectrochemistry is a subfield of study within physical chemistry concerned with the interaction of light with electrochemical systems. It is an active domain of investigation. One of the pioneers of this field of electrochemistry was the German electrochemist Heinz Gerischer. The interest in this domain is high in the context of development of renewable energy conversion and storage technology.
  • 455
  • 09 Oct 2022
Topic Review
Geothrix Fermentans
Geothrix fermentans is a rod-shaped, anaerobic bacterium. It is about 0.1 µm in diameter and ranges from 2-3 µm in length. Cell arrangement occurs singly and in chains. Geothrix fermentans can normally be found in aquatic sediments such as in aquifers. As an anaerobic chemoorganotroph, this organism is best known for its ability to use electron acceptors Fe(III), as well as other high potential metals. It also uses a wide range of substrates as electron donors. Research on metal reduction by G. fermentans has contributed to understanding more about the geochemical cycling of metals in the environment.
  • 448
  • 25 Nov 2022
Topic Review
Laboratory B in Sungul’
Laboratory B in Sungul' was one of the laboratories under the 9th Chief Directorate of the NKVD (MVD after 1946) that contributed to the Soviet atomic bomb project. It was created in 1946 and closed in 1955, when some of its personnel were merged with the second Soviet nuclear design and assembly facility. It was run as a sharashka – a secret scientific facility run as a prison. Laboratory B employed German scientists from 1947 to 1953. It had two scientific divisions, radiochemistry and radiobiophysics; the latter was headed by the world-renowned geneticist N. V. Timofeev-Resovskij. For two years, the renowned German chemist, Nikolaus Riehl was the scientific director.
  • 437
  • 08 Nov 2022
Topic Review
First Multi-Cavity Haloscopes in RADES
The first multi-cavity haloscopes for detection of dark matter axion in the RADES collaboration.
  • 436
  • 18 Jan 2022
Topic Review
Wireless USB
Wireless USB (Universal Serial Bus) was a short-range, high-bandwidth wireless radio communication protocol created by the Wireless USB Promoter Group which intended to increase the availability of general USB-based technologies. It was unrelated to Wi-Fi, and different from the Cypress WirelessUSB offerings. It was maintained by the WiMedia Alliance which ceased operations in 2009. Wireless USB is sometimes abbreviated as "WUSB", although the USB Implementers Forum discouraged this practice and instead prefers to call the technology Certified Wireless USB to distinguish it from the competing UWB standard. Wireless USB was based on the (now defunct) WiMedia Alliance's Ultra-WideBand (UWB) common radio platform, which is capable of sending 480 Mbit/s at distances up to 3 metres (9.8 ft) and 110 Mbit/s at up to 10 metres (33 ft). It was designed to operate in the 3.1 to 10.6 GHz frequency range, although local regulatory policies may restrict the legal operating range in some countries. The standard is now obsolete, and no new hardware has been produced for many years. Support for the standard was deprecated in Linux 5.4 and removed in Linux 5.7
  • 436
  • 28 Oct 2022
Topic Review
Black Holes and Quantum Mechanics
Mass and spin distributions of stellar mass black holes (BH) are important sources of information on the formation mechanism and the evolution of galaxies. The birth of a stellar-mass BH, ranging in the interval ~5–150 M⊙, is due to the spectacular phase of a massive star’s core collapse, an event involving the emission of multi-messenger signals such as neutrinos, GW’s and electromagnetic radiation in several bands.
  • 435
  • 03 Nov 2022
Topic Review
Stellar Magnetic Field
A stellar magnetic field is a magnetic field generated by the motion of conductive plasma inside a star. This motion is created through convection, which is a form of energy transport involving the physical movement of material. A localized magnetic field exerts a force on the plasma, effectively increasing the pressure without a comparable gain in density. As a result, the magnetized region rises relative to the remainder of the plasma, until it reaches the star's photosphere. This creates starspots on the surface, and the related phenomenon of coronal loops.
  • 369
  • 08 Oct 2022
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