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50-701: FLASH originated from the TESLA Test Facility (TTF), which was built in 1997 to test the technology foreseen for the planned linear collider TESLA, a project that was replaced by the International Linear Collider (ILC). For this purpose, the TTF was enlarged from 100 m to 260 m. FLASH also served as a test facility for the technology for the European XFEL . The facility currently serves seven experimental stations. It

100-455: A positron , each with a mass of 0.511 MeV/ c , can annihilate to yield 1.022 MeV of energy. A proton has a mass of 0.938 GeV/ c . In general, the masses of all hadrons are of the order of 1 GeV/ c , which makes the GeV/ c a convenient unit of mass for particle physics: The atomic mass constant ( m u ), one twelfth of the mass a carbon-12 atom, is close to

150-473: A $ 20 billion total. Upon completion of the 2013 ILC Design Report, Barish said the cost of building the ILC was the equivalent of 7.78 billion 2012 U.S. dollars; it will require "22.6 million hours of labor and location-specific costs including site preparation, scientific detectors and facility operations." GeV In physics , an electronvolt (symbol eV ), also written electron-volt and electron volt ,

200-433: A 370-meter linac stage. Synchrotron radiation from high energy electrons will produce electron-positron pairs on a titanium-alloy target, with as much as 60% polarization; the positrons from these collisions will be collected and accelerated to 5 GeV in a separate linac. To compact the 5 GeV electron and positron bunches to a sufficiently small size to be usefully collided, they will circulate for 0.1–0.2 seconds in

250-534: A circular design, particles can be effectively accelerated over longer distances. Also, only a fraction of the particles brought onto a collision course actually collide. In a linear accelerator, the remaining particles are lost; in a ring accelerator, they keep circulating and are available for future collisions. The disadvantage of circular accelerators is that charged particles moving along bent paths will necessarily emit electromagnetic radiation known as synchrotron radiation . Energy loss through synchrotron radiation

300-542: A pair of damping rings, 3.24 km in circumference, in which they will be reduced in size to 6 mm in length and a vertical and horizontal emittance of 2 pm and 0.6 nm, respectively. From the damping rings the particle bunches will be sent to the superconducting radio frequency main linacs, each 11 km long, where they will be accelerated to 250 GeV. At this energy each beam will have an average power of about 5.3 megawatts . Five bunch trains will be produced and accelerated per second. To maintain

350-491: A photon are related by E = h ν = h c λ = 4.135   667   696 × 10 − 15 e V / H z × 299 792 458 m / s λ {\displaystyle E=h\nu ={\frac {hc}{\lambda }}={\frac {\mathrm {4.135\ 667\ 696\times 10^{-15}\;eV/Hz} \times \mathrm {299\,792\,458\;m/s} }{\lambda }}} where h

400-588: A proposed linear particle accelerator . It is planned to have a collision energy of 500  GeV initially, with the possibility for a later upgrade to 1000 GeV (1 TeV). Although early proposed locations for the ILC were Japan, Europe ( CERN ) and the USA ( Fermilab ), the Kitakami highland in the Iwate prefecture of northern Japan has been the focus of ILC design efforts since 2013. The Japanese government

450-631: A sufficient luminosity to produce results in a reasonable time frame after acceleration the bunches will be focused to a few nanometers in height and a few hundred nanometers in width. The focused bunches then will be collided inside one of two large particle detectors . Originally, three sites for the International Linear Collider were leading contenders at established High Energy Physics centers in Europe. At CERN in Geneva

500-413: A system of natural units in which the speed of light in vacuum c and the reduced Planck constant ħ are dimensionless and equal to unity is widely used: c = ħ = 1 . In these units, both distances and times are expressed in inverse energy units (while energy and mass are expressed in the same units, see mass–energy equivalence ). In particular, particle scattering lengths are often presented using

550-686: A unit of inverse particle mass. Outside this system of units, the conversion factors between electronvolt, second, and nanometer are the following: ℏ = 1.054   571   817   646 × 10 − 34   J ⋅ s = 6.582   119   569   509 × 10 − 16   e V ⋅ s . {\displaystyle \hbar =1.054\ 571\ 817\ 646\times 10^{-34}\ \mathrm {J{\cdot }s} =6.582\ 119\ 569\ 509\times 10^{-16}\ \mathrm {eV{\cdot }s} .} The above relations also allow expressing

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600-443: A value of one volt , which is 1 J/C , multiplied by the elementary charge e  =  1.602 176 634 × 10  C . Therefore, one electronvolt is equal to 1.602 176 634 × 10  J . The electronvolt (eV) is a unit of energy, but is not an SI unit . It is a commonly used unit of energy within physics, widely used in solid state , atomic , nuclear and particle physics, and high-energy astrophysics . It

650-403: A wavelength of 532 nm (green light) would have an energy of approximately 2.33 eV . Similarly, 1 eV would correspond to an infrared photon of wavelength 1240 nm or frequency 241.8 THz . In a low-energy nuclear scattering experiment, it is conventional to refer to the nuclear recoil energy in units of eVr, keVr, etc. This distinguishes the nuclear recoil energy from

700-399: Is a Pythagorean equation . When a relatively high energy is applied to a particle with relatively low rest mass , it can be approximated as E ≃ p {\displaystyle E\simeq p} in high-energy physics such that an applied energy with expressed in the unit eV conveniently results in a numerically approximately equivalent change of momentum when expressed with

750-462: Is also used as a test facility for plasma wakefield acceleration at the FLASHForward experiment. Since 2020, it has been expanded to further optimise the properties of the radiation (FLASH2020+ project). This accelerator physics -related article is a stub . You can help Misplaced Pages by expanding it . International Linear Collider The International Linear Collider ( ILC ) is

800-461: Is an SI unit. In the fields of physics in which the electronvolt is used, other quantities are typically measured using units derived from the electronvolt as a product with fundamental constants of importance in the theory are often used. By mass–energy equivalence , the electronvolt corresponds to a unit of mass . It is common in particle physics , where units of mass and energy are often interchanged, to express mass in units of eV/ c , where c

850-436: Is commonly used with SI prefixes milli- (10 ), kilo- (10 ), mega- (10 ), giga- (10 ), tera- (10 ), peta- (10 ) or exa- (10 ), the respective symbols being meV, keV, MeV, GeV, TeV, PeV and EeV. The SI unit of energy is the joule (J). In some older documents, and in the name Bevatron , the symbol BeV is used, where the B stands for billion . The symbol BeV is therefore equivalent to GeV , though neither

900-794: Is convenient to use the electronvolt to express temperature. The electronvolt is divided by the Boltzmann constant to convert to the Kelvin scale : 1 e V / k B = 1.602   176   634 × 10 − 19  J 1.380   649 × 10 − 23  J/K = 11   604.518   12  K , {\displaystyle {1\,\mathrm {eV} /k_{\text{B}}}={1.602\ 176\ 634\times 10^{-19}{\text{ J}} \over 1.380\ 649\times 10^{-23}{\text{ J/K}}}=11\ 604.518\ 12{\text{ K}},} where k B

950-509: Is inversely proportional to the fourth power of the mass of the particles in question. That is why it makes sense to build circular accelerators for heavy particles—hadron colliders such as the LHC for protons or, alternatively, for lead nuclei . An electron–positron collider of the same size would never be able to achieve the same collision energies. In fact, energies at the LEP which used to occupy

1000-441: Is the Boltzmann constant . The k B is assumed when using the electronvolt to express temperature, for example, a typical magnetic confinement fusion plasma is 15 keV (kiloelectronvolt), which is equal to 174 MK (megakelvin). As an approximation: k B T is about 0.025 eV (≈ ⁠ 290 K / 11604 K/eV ⁠ ) at a temperature of 20 °C . The energy E , frequency ν , and wavelength λ of

1050-663: Is the Planck constant , c is the speed of light . This reduces to E = 4.135   667   696 × 10 − 15 e V / H z × ν = 1   239.841   98 e V ⋅ n m λ . {\displaystyle {\begin{aligned}E&=4.135\ 667\ 696\times 10^{-15}\;\mathrm {eV/Hz} \times \nu \\[4pt]&={\frac {1\ 239.841\ 98\;\mathrm {eV{\cdot }nm} }{\lambda }}.\end{aligned}}} A photon with

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1100-901: Is the speed of light in vacuum (from E = mc ). It is common to informally express mass in terms of eV as a unit of mass , effectively using a system of natural units with c set to 1. The kilogram equivalent of 1 eV/ c is: 1 eV / c 2 = ( 1.602   176   634 × 10 − 19 C ) × 1 V ( 299   792   458 m / s ) 2 = 1.782   661   92 × 10 − 36 kg . {\displaystyle 1\;{\text{eV}}/c^{2}={\frac {(1.602\ 176\ 634\times 10^{-19}\,{\text{C}})\times 1\,{\text{V}}}{(299\ 792\ 458\;\mathrm {m/s} )^{2}}}=1.782\ 661\ 92\times 10^{-36}\;{\text{kg}}.} For example, an electron and

1150-447: Is the measure of an amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in vacuum . When used as a unit of energy , the numerical value of 1 eV in joules (symbol J) is equal to the numerical value of the charge of an electron in coulombs (symbol C). Under the 2019 revision of the SI , this sets 1 eV equal to

1200-416: Is willing to contribute half of the costs, according to the coordinator of study for detectors at the ILC. The ILC would collide electrons with positrons . It will be between 30 km and 50 km (19–31 mi) long, more than 10 times as long as the 50 GeV Stanford Linear Accelerator , the longest existing linear particle accelerator. The proposal is based on previous similar proposals from Europe,

1250-498: The Future Circular Collider , which has overlapping physics goals with the ILC. In March 2024, the "Federation of Diet Members for the ILC" met to receive "Reports on the ILC project's progress and initiatives by relevant organizations". Fifty participants, including Diet members and other government agencies, as well as researchers and businesses, received reports on the project's progress. Participants discussed

1300-674: The T2K experiment , a factor not in its favor, although 20 huge caverns with access tunnels have already been constructed in Japan for hydroelectric power plants (e.g. the Kannagawa Hydropower Plant ). Following the closure of the Tevatron some groups within the USA had expressed interest, with Fermilab being a favored site because of the facilities and experts already present. Much of the speculated interest from other countries

1350-410: The mean lifetime τ of an unstable particle (in seconds) in terms of its decay width Γ (in eV) via Γ = ħ / τ . For example, the B meson has a lifetime of 1.530(9)  picoseconds , mean decay length is cτ = 459.7 μm , or a decay width of 4.302(25) × 10  eV . Conversely, the tiny meson mass differences responsible for meson oscillations are often expressed in

1400-483: The "electron equivalent" recoil energy (eVee, keVee, etc.) measured by scintillation light. For example, the yield of a phototube is measured in phe/keVee ( photoelectrons per keV electron-equivalent energy). The relationship between eV, eVr, and eVee depends on the medium the scattering takes place in, and must be established empirically for each material. One mole of particles given 1 eV of energy each has approximately 96.5 kJ of energy – this corresponds to

1450-477: The ILC's future. The meeting resulted in three recommendations: 1. The ILC project will be further promoted by the research community, industry, organizations promoting the candidate sites, relevant ministries and agencies, the Diet members and other political organizations within an all-Japan framework. 2. For the ILC project, international collaboration will be further strengthened as a global initiative involving

1500-638: The ILC, have been unified under the Linear Collider Collaboration . There are two basic shapes of accelerators. Linear accelerators ("linacs") accelerate elementary particles along a straight path. Circular accelerators ("synchrotrons"), such as the Tevatron , the LEP , and the Large Hadron Collider (LHC), use circular paths. Circular geometry has significant advantages at energies up to and including tens of GeV : With

1550-602: The International Linear Collider. On August 23, 2013, the Japanese high-energy physics community's site evaluation committee proposed it should be located in the Kitakami Mountains of the Iwate and Miyagi Prefectures . As of March 7, 2019, the Japanese government has stated that it is not ready to support the construction of the Collider due to its high proposed cost of approximately $ 7 billion. This decision

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1600-897: The Next Linear Collider (NLC), the Global Linear Collider (GLC) and Teraelectronvolt Energy Superconducting Linear Accelerator (TESLA) – joined their efforts into one single project (the ILC). In March 2005, the International Committee for Future Accelerators (ICFA) announced Prof. Barry Barish , director of the LIGO Laboratory at Caltech from 1997 to 2005, as the Director of the Global Design Effort (GDE). In August 2007,

1650-575: The Reference Design Report for the ILC was released. Physicists working on the GDE completed a detailed ILC design report, publishing it in June 2013. The electron source for the ILC will use 2-nanosecond laser light pulses to eject electrons from a photocathode , a technique allowing for up to 80% of the electrons to be polarized; the electrons then will be accelerated to 5 GeV in

1700-570: The Standard Model are expected to be discovered and measured. At the ILC physicists hope to be able to: To achieve these goals, new generation particle detectors are necessary. In August 2004, the International Technology Recommendation Panel (ITRP) recommended a superconducting radio frequency technology for the accelerator. After this decision the three existing linear collider projects –

1750-480: The U.S., and Japan. In a staged approach, the ILC could initially be constructed at 250 GeV, for use as a Higgs factory . Such a design would be approximately 20 km in length. Studies for an alternative project, the Compact Linear Collider (CLIC) are also underway, which would operate at higher energies (up to 3 TeV) in a machine of length similar to the ILC. These two projects, CLIC and

1800-432: The accelerator complex and detectors is expected to require seven years. The host country would be required to pay $ 1.8 billion for site-specific costs like digging tunnels and shafts and supplying water and electricity. Former U.S. Secretary of Energy Steven Chu estimated the total cost to be US$ 25 billion. ILC Director Barish said this is likely to be an overestimate. Other Department of Energy officials have estimated

1850-876: The conversion to MKS system of units can be achieved by: p = 1 GeV / c = ( 1 × 10 9 ) × ( 1.602   176   634 × 10 − 19 C ) × ( 1 V ) 2.99   792   458 × 10 8 m / s = 5.344   286 × 10 − 19 kg ⋅ m / s . {\displaystyle p=1\;{\text{GeV}}/c={\frac {(1\times 10^{9})\times (1.602\ 176\ 634\times 10^{-19}\;{\text{C}})\times (1\;{\text{V}})}{2.99\ 792\ 458\times 10^{8}\;{\text{m}}/{\text{s}}}}=5.344\ 286\times 10^{-19}\;{\text{kg}}{\cdot }{\text{m}}/{\text{s}}.} In particle physics ,

1900-447: The energy is distributed among the constituent quarks , antiquarks and gluons of baryonic particles. As such, one of the roles of the ILC would be making precision measurements of the properties of particles discovered at the LHC. It is widely expected that effects of physics beyond that described in the current Standard Model will be detected by experiments at the proposed ILC. In addition, particles and interactions described by

1950-479: The exact value 1.602 176 634 × 10  J . Historically, the electronvolt was devised as a standard unit of measure through its usefulness in electrostatic particle accelerator sciences, because a particle with electric charge q gains an energy E = qV after passing through a voltage of V . An electronvolt is the amount of energy gained or lost by a single electron when it moves through an electric potential difference of one volt . Hence, it has

2000-641: The global accelerator program. This collaboration should utilize the framework of the Liaison Committee on Future High-Performance Accelerators, in partnership with the Cabinet Office, as well as other relevant ministries and agencies. The Reference Design Report estimated the cost of building the ILC, excluding R&D, prototyping, land acquisition, underground easement costs, detectors, contingencies, and inflation, at US$ 6.75 billion (in 2007 prices). From formal project approval, completion of

2050-404: The mass of a proton. To convert to electronvolt mass-equivalent, use the formula: By dividing a particle's kinetic energy in electronvolts by the fundamental constant c (the speed of light), one can describe the particle's momentum in units of eV/ c . In natural units in which the fundamental velocity constant c is numerically 1, the c may be informally be omitted to express momentum using

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2100-985: The more convenient inverse picoseconds. Energy in electronvolts is sometimes expressed through the wavelength of light with photons of the same energy: 1 eV h c = 1.602   176   634 × 10 − 19 J ( 2.99   792   458 × 10 11 mm / s ) × ( 6.62   607   015 × 10 − 34 J ⋅ s ) ≈ 806.55439 mm − 1 . {\displaystyle {\frac {1\;{\text{eV}}}{hc}}={\frac {1.602\ 176\ 634\times 10^{-19}\;{\text{J}}}{(2.99\ 792\ 458\times 10^{11}\;{\text{mm}}/{\text{s}})\times (6.62\ 607\ 015\times 10^{-34}\;{\text{J}}{\cdot }{\text{s}})}}\thickapprox 806.55439\;{\text{mm}}^{-1}.} In certain fields, such as plasma physics , it

2150-495: The research community. This will be achieved through close cooperation between the ILC International Development Team (IDT), an international promotion organization established under ICFA, and the domestic research community. 3. The Ministry of Education, Culture, Sports, Science and Technology (MEXT) should play an active role in collaborating with the international research community to achieve

2200-409: The surface in non-permeable soil. Dubna has a pre-accelerator complex which could have been easily adapted for the needs for the ILC. But all three were more or less well suited for housing a Linear Collider and one had ample choice for a site selection process in Europe. Outside Europe a number of countries expressed interest. Japan receives a large amount of funding for neutrino activities, such as

2250-561: The tunnel is located deep underground in non-permeable bedrock. This site was considered favorable for a number of practical reasons but due to the LHC the site was disfavored. At DESY in Hamburg the tunnel is close to the surface in water saturated soil. Germany leads Europe for scientific funding and was therefore considered reliable in terms of funding. At JINR in Dubna the tunnel is close to

2300-417: The tunnel now given over to the LHC, were limited to 209 GeV by energy loss via synchrotron radiation. Even though the nominal collision energy at the LHC will be higher than the ILC collision energy (14,000  GeV for the LHC vs. ~500 GeV for the ILC), measurements could be made more accurately at the ILC. Collisions between electrons and positrons are much simpler to analyze than collisions in which

2350-441: The unit electronvolt. The energy–momentum relation E 2 = p 2 c 2 + m 0 2 c 4 {\displaystyle E^{2}=p^{2}c^{2}+m_{0}^{2}c^{4}} in natural units (with c = 1 {\displaystyle c=1} ) E 2 = p 2 + m 0 2 {\displaystyle E^{2}=p^{2}+m_{0}^{2}}

2400-404: The unit eV/ c . The dimension of momentum is T L M . The dimension of energy is T L M . Dividing a unit of energy (such as eV) by a fundamental constant (such as the speed of light) that has the dimension of velocity ( T L ) facilitates the required conversion for using a unit of energy to quantify momentum. For example, if the momentum p of an electron is 1 GeV/ c , then

2450-554: Was hearsay from within the scientific community, and very few facts were published officially. The information presented above is a summary of that contained in the International Workshop on Linear Colliders 2010 (ECFA-CLIC-ILC Joint Meeting) at CERN. The 2008 economic crisis led the United States and United Kingdom to cut funds to the collider project, leading to Japan's position as the most likely host for

2500-527: Was informed partly by the Science Council of Japan . The Japanese government sought monetary support from other countries to help fund this project. In 2022, the Japanese plan for the ILC was "shelved" by a panel for Japan’s Ministry of Education, Culture, Sports, Science and Technology (MEXT) Several reasons were given, including potentially insufficient international support and the CERN proposal for

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