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 magnetic field which bends the particle beam into its closed p ...

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 River A ...

(PSI) in

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

for producing

electromagnetic radiation In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic field, electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, inf ...

of high

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

. 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 GEV may refer to: * ''G.E.V.'' (board game), a tabletop game by Steve Jackson Games * Ashe County Airport, in North Carolina, United States * Gällivare Lapland Airport, in Sweden * Generalized extreme value distribution * Gev Sella, Israeli-Sou ...

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 of th ...

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. T ...

s of 1.4 tesla 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 tesla 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 A sextupole magnet (also known as a hexapole magnet) consist of six magnetic poles set out in an arrangement of alternating north and south poles arranged around an axis. They are used in particle accelerators for the control of chromatic aberra ...

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 deals with the separation of the positive and negative electric charges found in any electromagnetic system. A simple example of this system i ...

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 beam ...

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 A magnetic chicane also called a bunch compressor helps form dense bunches of electrons in a free-electron laser. A magnetic chicane makes electrons detour slightly from their otherwise straight bath, and in that way is similar to a chicane on a ...

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 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. T ...

s) 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 determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

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

pharmaceutical companies The pharmaceutical industry discovers, develops, produces, and markets drugs or pharmaceutical drugs for use as medications to be administered to patients (or self-administered), with the aim to cure them, vaccinate them, or alleviate symptoms. ...

including

Novartis Novartis AG is a Swiss-American multinational pharmaceutical corporation based in Basel, Switzerland and Cambridge, Massachusetts, United States (global research).name="novartis.com">https://www.novartis.com/research-development/research-loc ...

Roche F. Hoffmann-La Roche AG, commonly known as Roche, is a Swiss multinational healthcare company that operates worldwide under two divisions: Pharmaceuticals and Diagnostics. Its holding company, Roche Holding AG, has shares listed on the SIX S ...

Actelion Actelion is a pharmaceuticals and biotechnology company established in December 1997, headquartered in Allschwil near Basel, Switzerland. Actelion focuses on the manufacture of drugs that treat rare diseases and orphan diseases. Some of the dru ...

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 in Ingelheim am Rhein, Germany. As of 2018, Boehringer Ingelheim is one of the world's largest pharmaceutical ...

and Proteros.

References

External links

* {{authority control Synchrotron radiation facilities

See also

References

External links