The Swiss Light Source (SLS) is a

synchrotron A synchrotron is a particular type of cyclic particle accelerator, descended from the cyclotron, in which the accelerating particle beam travels around a fixed closed-loop path. The strength of the magnetic field which bends the particle beam i ...

located at the

Paul Scherrer Institute The Paul Scherrer Institute (PSI) is a multi-disciplinary research institute for natural and engineering sciences in Switzerland. It is located in the Canton of Aargau in the municipalities Villigen and Würenlingen on either side of the Ri ...

(PSI) in

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

for producing

electromagnetic radiation In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...

of high

brightness Brightness is an attribute of visual perception in which a source appears to be radiating/reflecting light. In other words, brightness is the perception dictated by the luminance of a visual target. The perception is not linear to luminance, and ...

. Planning started in 1991, the project was approved in 1997, and first light from the storage ring was seen at December 15, 2000. The experimental program started in June 2001 and it is used for research in materials science, biology and chemistry. Main component of the SLS is the 2.4

GeV In physics, an electronvolt (symbol eV), also written electron-volt and electron volt, 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 us ...

electron

storage ring A storage ring is a type of circular particle accelerator in which a continuous or pulsed particle beam may be kept circulating, typically for many hours. Storage of a particular particle depends upon the mass, momentum, and usually the charge o ...

of 288 m circumference: The ring is formed by 36

dipole magnet A dipole magnet is the simplest type of magnet. It has two poles, one north and one south. Its magnetic field lines form simple closed loops which emerge from the north pole, re-enter at the south pole, then pass through the body of the magnet. ...

s of 1.4

tesla Tesla most commonly refers to: * Nikola Tesla (1856–1943), a Serbian-American electrical engineer and inventor * Tesla, Inc., an American electric vehicle and clean energy company, formerly Tesla Motors, Inc. * Tesla (unit) (symbol: T), the SI-d ...

magnetic field, combined in 12 groups of three (triple bend achromat, TBA) for achromatic deflection of the electron beam. 12 straight sections between the TBAs of different lengths (3×11.5 m, 3×7 m, 6×4 m) accommodate the

undulator An undulator is an insertion device from high-energy physics and usually part of a larger installation, a synchrotron storage ring, or it may be a component of a free electron laser. It consists of a periodic structure of dipole magnets. These ca ...

magnets to generate ultraviolet and X-ray light of extreme

. 3 of the dipoles have an increased center field of 3

to produce hard X-rays. A total of 177

quadrupole magnet Quadrupole magnets, abbreviated as Q-magnets, consist of groups of four magnets laid out so that in the planar multipole expansion of the field, the dipole terms cancel and where the lowest significant terms in the field equations are quadrupole. ...

s (magnetic lenses) focuses the beam to provide a

beam emittance In accelerator physics, emittance is a property of a charged particle beam. It refers to the area occupied by the beam in a position-and-momentum phase space. Each particle in a beam can be described by its position and momentum along each of t ...

of 5.5 nm rad. 120

sextupole magnet file:Aust.-Synchrotron,-Sextupole-Focusing-Magnet,-14.06.2007.jpg, 250px, Sextupole electromagnet as used within the storage ring of the Australian Synchrotron to correct chromatic aberrations of the electron beam file:magnetic field of an idealiz ...

s correct the chromatic focusing errors of the quadrupoles. 73 horizontal and vertical beam steerers are used to continuously correct the position of the electron beam. Finally 24 skew quadrupole magnets are adjusted to correct any torsion of the beam and to minimize the vertical emittance: a world record low value of 3 pm rad has been achieved in 2008. The SLS has achieved a photon beam stability of 1 micrometre: the ring is operated in top-up mode, i.e. the stored current of 400 mA is kept constant to 2 mA by frequent (2–3 minutes) injections. This maintains a constant thermal load from synchrotron radiation. A fast orbit feedback system controlling the 73 beam position monitors and the 73 horizontal and vertical steerers corrects the position of the electron beam 4000 times per second to suppress any distortions from ground vibrations etc. Beam distortions from changing the undulator status as done during experiments are minimized by application of a set of feed forward corrections measured once for the undulators, the orbit feedback takes care of the rest. Finally X-ray beam position monitors measuring the location of the synchrotron radiation itself perform the final adjustment in front of the experiment. SLS has a booster

optimized for top-up operation: it provides a low

of 10 nm rad for efficient beam injection into the storage ring, and it has a low average power consumption of 30 kW. This is achieved by a large circumference of 270 m, a large number (93) of small

dipole In physics, a dipole () is an electromagnetic phenomenon which occurs in two ways: * An electric dipole moment, electric dipole deals with the separation of the positive and negative electric charges found in any electromagnetic system. A simple ...

magnets and a low aperture of only 30x20mm. The booster accelerates the beam from 100 MeV to 2.4 GeV (optional 2.7 GeV) at a repetition time of 320 ms. A 100 MeV

linear accelerator A linear particle accelerator (often shortened to linac) is a type of particle accelerator that accelerates charged subatomic particles or ions to a high speed by subjecting them to a series of oscillating electric potentials along a linear ...

as pre-injector completes the facility. In 2006 the SLS-FEMTO facility came into operation: By interaction of a high energy (4 mJ), short pulse (50 fs fwhm) laser pulse with the electron beam in a wiggler magnet, a thin ''slice'' of the electron beam is modulated in energy. A magnetic chicane bracketing the wiggler and creating dispersion translates this energy modulation into a horizontal separation of the slices from the core beam. So radiation from the slices in a subsequent undulator can be separated by a system of apertures. In this way X-ray pulses of 140 fs length (fwhm) and a tunable photon energy of 3-18 keV can be generated. (This installation caused a major change of the storage ring resulting in the odd numbers of 177 quadrupoles and 73 steerers.) FEMTO experiments were discontinued in 2017, since the manpower was transferred to an experimental station at the

SwissFEL SwissFEL is the X-ray free-electron laser at the Paul Scherrer Institute (PSI), which was inaugurated in December 2016. The SwissFEL design is optimised to generate X-ray pulses in the wavelength range of 1 Å to 70 Å. With an overall length of j ...

. As of June 2009 SLS has eighteen experimental stations (

s and bending magnets) and seventeen operational

beamlines In accelerator physics, a beamline refers to the trajectory of the beam of particles, including the overall construction of the path segment (guide tubes, diagnostic devices) along a specific path of an accelerator facility. This part is either ...

. There are three

protein crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract in specific directions. By measuring the angles and ...

beam-lines, two of which are partially funded by associations of Swiss

pharmaceutical companies The pharmaceutical industry is a Medicine, medical industry that discovers, develops, produces, and markets pharmaceutical goods such as medications and medical devices. Medications are then administered to (or Self-medicate, self-administered b ...

including

Novartis Novartis AG is a Swiss multinational corporation, multinational pharmaceutical company, pharmaceutical corporation based in Basel, Switzerland. Novartis is one of the largest pharmaceutical companies in the world and was the eighth largest by re ...

Roche F. Hoffmann-La Roche AG, commonly known as Roche (), is a Switzerland, Swiss multinational corporation, multinational holding healthcare company that operates worldwide under two divisions: Pharmaceuticals and Diagnostics. Its holding company, ...

Actelion Actelion Pharmaceuticals Ltd. is a pharmaceuticals and biotechnology company established in December 1997, headquartered in Allschwil near Basel, Switzerland. The company is part of Johnson & Johnson Innovative Medicine business segment. Actel ...

Boehringer Ingelheim C.H. Boehringer Sohn AG & Co. is the parent company of the Boehringer Ingelheim group, which was founded in 1885 by Albert Boehringer (1861–1939) in Ingelheim am Rhein, Germany. As of 2018, Boehringer Ingelheim is one of the world's List of la ...

and Proteros.

References

External links

* {{authority control Synchrotron radiation facilities

See also

References

External links