National Synchrotron Light Source
Encyclopedia
The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory
(BNL) in Upton, New York
is a national user research facility funded by the U.S. Department of Energy (DOE). The NSLS, is considered a second generation synchrotron
, and was built beginning in 1978 and finished in 1984.
The NSLS experimental floor consists of two electron storage rings: an X-Ray
ring and a VUV (Vacuum Ultra Violet) Ring which provide intense focused light spanning the electromagnetic spectrum from the infrared through x-rays. The properties of this light and the specially designed experimental stations, called beamline
s, allow scientists in many fields of research to perform experiments not otherwise possible at their own laboratories.
During the construction of the NSLS, two scientists, Renate Chasman
and G. Kenneth Green, invented a special periodic arrangement of magnetic elements, a so-called magnetic lattice, to provide optimized bending and focusing of electrons. The design called the Chasman–Green lattice, and it is the basis of design for every synchrotron
storage ring. It is common to refer to storage rings by the number of straight sections and bend sections. The bend sections, produced more light than the straight sections due to the change in angular momentum
of the electrons. Yet, Chaseman and Green accounted for this in their design by adding wigglers
and undulator
s in the straight sections of the storage ring, this resulted in very bright light also being produced by these sections. In fact these insertion devices, wigglers
and undulator
s, produce the brightest light. Beamline
s that are downstream from these insertion devices receive the brightest light.
The VUV Ring at the National Synchrotron Light Source was one of the first of the 2nd generation light sources to operate in the world. It was initially designed in 1976 and commissioned in 1983. During the Phase II upgrade in 1986, two insertion wigglers/undulators were added to the VUV ring providing the highest brightness source in the vacuum ultra-violet region until the advent of 3rd generation sources.
. The final lattice design was completed in 1978 and the first stored beam was obtained in September 1982. By 1985 the experimental program was in a rapid state of development, and by the end of 1990 the Phase II beamlines and insertion devices were being brought into operation.
triode electron gun. These electrons then procceed through a linac, linear accelerator, which gets them up to 120MeV
. Next, the electrons enter a booster ring, where they are increased to 750MeV
, and are then injected into either the VUV ring or the X-ray ring. If they enter the VUV ring they are ramped up further to about 825MeV
and if they enter the X-ray ring they are ramped to 2.800GeV
.
Once in the ring, VUV or X-ray, the electrons orbit and lose energy as a result of changes in angular momentum
which cause the expulsion of photons. These photons are deemed white light, i.e. polychromatic
, and are the source of synchrotron radiation. To get a single and fixed wavelength at the end station, a monochromator
is used. Yet prior to entering the monochromator the light is collimated
.
As mentioned above, during normal operations the electrons in the storage rings lose energy and as such every 12 (X-ray ring) and 4 (VUV ring) hours the rings must be re-injected. The difference in time arises from the fact that VUV light has a bigger wavelength and thus has lower energy which leads to faster decay, while the X-rays have a very small wavelength and are high energy.
Each X-ray beamline
has an end station called, a hutch
, these are large enclosures made of lead to protect the users from the ionizing radiation
of the beam. On the X-ray floor, many of the experiment conducted use techniques such as XRD
, XAFS
, DAFS (X-ray diffraction anomalous fine structure), WAXS
, and SAXS
.
On the UV-ring, the end stations are usually UHV (ultra high vacuum
) chambers that are used to conduct experiments like XPS
, UPS
, LEEM
and NEXAFS.
Usually in every beamline
there are other analytical tools such as, a MS
or a GC-MS
. These techniques help supplement and better quantify the experiments carried out at the end station.
won the Nobel Prize in Chemistry
for deciphering the structure of neuronal ion channel
, his work was in part conducted at the NSLS.
Brookhaven National Laboratory
Brookhaven National Laboratory , is a United States national laboratory located in Upton, New York on Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base...
(BNL) in Upton, New York
Upton, New York
Upton, New York is a hamlet on Long Island in the town of Brookhaven. It is the home of Brookhaven National Laboratory, and a National Weather Service station.Upton is located in Suffolk County, New York in the USA....
is a national user research facility funded by the U.S. Department of Energy (DOE). The NSLS, is considered a second generation synchrotron
Synchrotron
A synchrotron is a particular type of cyclic particle accelerator in which the magnetic field and the electric field are carefully synchronised with the travelling particle beam. The proton synchrotron was originally conceived by Sir Marcus Oliphant...
, and was built beginning in 1978 and finished in 1984.
The NSLS experimental floor consists of two electron storage rings: an X-Ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
ring and a VUV (Vacuum Ultra Violet) Ring which provide intense focused light spanning the electromagnetic spectrum from the infrared through x-rays. The properties of this light and the specially designed experimental stations, called beamline
Beamline
In particle physics, a beamline is the line in a linear accelerator along which a beam of particles travels. It may also refer to the line of travel within a bending section such as a storage ring or cyclotron, or an external beam extracted from a cyclic accelerator.In materials science, physics,...
s, allow scientists in many fields of research to perform experiments not otherwise possible at their own laboratories.
History
Ground was broken for the NSLS on September 28, 1978. The vacuum ultraviolet (VUV) ring began operations in late 1982 and the x-ray ring was commissioned in 1984. In 1986, a second phase of construction expanded the NSLS by 52000 square feet (4,831 m²). This added offices, laboratories and room for new experimental equipment.During the construction of the NSLS, two scientists, Renate Chasman
Renate Chasman
Renate Wiener Chasman was a physicist.She was born Renate Wiener to German Jewish parents in Berlin. Her father, Hans Wiener, was a founder of the Social Democratic Party of Germany...
and G. Kenneth Green, invented a special periodic arrangement of magnetic elements, a so-called magnetic lattice, to provide optimized bending and focusing of electrons. The design called the Chasman–Green lattice, and it is the basis of design for every synchrotron
Synchrotron
A synchrotron is a particular type of cyclic particle accelerator in which the magnetic field and the electric field are carefully synchronised with the travelling particle beam. The proton synchrotron was originally conceived by Sir Marcus Oliphant...
storage ring. It is common to refer to storage rings by the number of straight sections and bend sections. The bend sections, produced more light than the straight sections due to the change in angular momentum
Angular momentum
In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system...
of the electrons. Yet, Chaseman and Green accounted for this in their design by adding wigglers
Wiggler (synchrotron)
A wiggler is an insertion device in a synchrotron. It is a series of magnets designed to periodically laterally deflect a beam of charged particles inside a storage ring of a synchrotron...
and undulator
Undulator
An undulator is an insertion device from high-energy physics and usually part of a largerinstallation, a synchrotron storage ring. It consists of a periodic structure of dipole magnets . The static magnetic field is alternating along the length of the undulator with a wavelength \lambda_u...
s in the straight sections of the storage ring, this resulted in very bright light also being produced by these sections. In fact these insertion devices, wigglers
Wiggler (synchrotron)
A wiggler is an insertion device in a synchrotron. It is a series of magnets designed to periodically laterally deflect a beam of charged particles inside a storage ring of a synchrotron...
and undulator
Undulator
An undulator is an insertion device from high-energy physics and usually part of a largerinstallation, a synchrotron storage ring. It consists of a periodic structure of dipole magnets . The static magnetic field is alternating along the length of the undulator with a wavelength \lambda_u...
s, produce the brightest light. Beamline
Beamline
In particle physics, a beamline is the line in a linear accelerator along which a beam of particles travels. It may also refer to the line of travel within a bending section such as a storage ring or cyclotron, or an external beam extracted from a cyclic accelerator.In materials science, physics,...
s that are downstream from these insertion devices receive the brightest light.
VUV ring
X-ray ring
The X-ray ring at the National Synchrotron Light Source was one of the first storage rings designed as a dedicated source of synchrotron radiationSynchrotron radiation
The electromagnetic radiation emitted when charged particles are accelerated radially is called synchrotron radiation. It is produced in synchrotrons using bending magnets, undulators and/or wigglers...
. The final lattice design was completed in 1978 and the first stored beam was obtained in September 1982. By 1985 the experimental program was in a rapid state of development, and by the end of 1990 the Phase II beamlines and insertion devices were being brought into operation.
Design
Electrons are the generators of the synchrotron radiation that is used at the end stations of beamlines. The electrons are first produced by a 100KeVElectronvolt
In physics, the electron volt is a unit of energy equal to approximately joule . By definition, it is equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electric potential difference of one volt...
triode electron gun. These electrons then procceed through a linac, linear accelerator, which gets them up to 120MeV
Electronvolt
In physics, the electron volt is a unit of energy equal to approximately joule . By definition, it is equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electric potential difference of one volt...
. Next, the electrons enter a booster ring, where they are increased to 750MeV
Electronvolt
In physics, the electron volt is a unit of energy equal to approximately joule . By definition, it is equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electric potential difference of one volt...
, and are then injected into either the VUV ring or the X-ray ring. If they enter the VUV ring they are ramped up further to about 825MeV
Electronvolt
In physics, the electron volt is a unit of energy equal to approximately joule . By definition, it is equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electric potential difference of one volt...
and if they enter the X-ray ring they are ramped to 2.800GeV
Electronvolt
In physics, the electron volt is a unit of energy equal to approximately joule . By definition, it is equal to the amount of kinetic energy gained by a single unbound electron when it accelerates through an electric potential difference of one volt...
.
Once in the ring, VUV or X-ray, the electrons orbit and lose energy as a result of changes in angular momentum
Angular momentum
In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system...
which cause the expulsion of photons. These photons are deemed white light, i.e. polychromatic
Polychromatic
The term polychromatic means having several colours.It is used to describe light that exhibits more than one color. In a technical respect, this can also mean that it contains radiation of more than one wavelength. The study of polychromatics is particularly useful in the production of diffraction...
, and are the source of synchrotron radiation. To get a single and fixed wavelength at the end station, a monochromator
Monochromator
A monochromator is an optical device that transmits a mechanically selectable narrow band of wavelengths of light or other radiation chosen from a wider range of wavelengths available at the input...
is used. Yet prior to entering the monochromator the light is collimated
Collimator
A collimator is a device that narrows a beam of particles or waves. To "narrow" can mean either to cause the directions of motion to become more aligned in a specific direction or to cause the spatial cross section of the beam to become smaller.- Optical collimators :In optics, a collimator may...
.
As mentioned above, during normal operations the electrons in the storage rings lose energy and as such every 12 (X-ray ring) and 4 (VUV ring) hours the rings must be re-injected. The difference in time arises from the fact that VUV light has a bigger wavelength and thus has lower energy which leads to faster decay, while the X-rays have a very small wavelength and are high energy.
Facilities
There is a UV ring and a X-ray ring. The UV ring has 19 beamlines (13 are operational) and the X-ray ring has 58 beamlines (51 are operational). The beamlines are operated and funded in numerous ways, yet the NSLS is a user facility and as such any scientist that submits a proposal can be granted beam time. There are two types of beamlines at the NSLS: Facility Beamlines (FBs), of which there are 18; and Participating Research Team (PRT) beamlines, currently totaling 46. FBs are operated by the NSLS staff and reserve a minimum of 50 percent of their beam time for users and PRT beamlines reserve 25 percent of their beam time for users.Each X-ray beamline
Beamline
In particle physics, a beamline is the line in a linear accelerator along which a beam of particles travels. It may also refer to the line of travel within a bending section such as a storage ring or cyclotron, or an external beam extracted from a cyclic accelerator.In materials science, physics,...
has an end station called, a hutch
Hutch
-People:* Ken Hutcherson, former National Football League linebacker, pastor of Antioch Bible Church in Kirkland, Washington* Leslie Hutchinson, a popular singer of the 1930s known as 'Hutch'* Jesse Hutch, actor...
, these are large enclosures made of lead to protect the users from the ionizing radiation
Ionizing radiation
Ionizing radiation is radiation composed of particles that individually have sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, which are atoms or molecules containing unpaired electrons...
of the beam. On the X-ray floor, many of the experiment conducted use techniques such as XRD
X-ray crystallography
X-ray crystallography is a method of determining the arrangement of atoms within a crystal, in which a beam of X-rays strikes a crystal and causes the beam of light to spread into many specific directions. From the angles and intensities of these diffracted beams, a crystallographer can produce a...
, XAFS
X-ray absorption fine structure
X-ray absorption fine structure is a specific structure observed in X-ray absorption spectroscopy . By analyzing the XAFS, information can be acquired on the local structure and on the unoccupied electronic states.-Spectra:...
, DAFS (X-ray diffraction anomalous fine structure), WAXS
Wide angle X-ray scattering
Wide angle X-ray scattering or Wide angle X-ray diffraction is an X-ray diffraction technique that is often used to determine the crystalline structure of polymers...
, and SAXS
Small-angle X-ray scattering
Small-angle X-ray scattering is a small-angle scattering technique where the elastic scattering of X-rays by a sample which has inhomogeneities in the nm-range, is recorded at very low angles...
.
On the UV-ring, the end stations are usually UHV (ultra high vacuum
Ultra high vacuum
Ultra-high vacuum is the vacuum regime characterised by pressures lower than about 10−7 pascal or 100 nanopascals . UHV requires the use of unusual materials in construction and by heating the entire system to 180°C for several hours to remove water and other trace gases which adsorb on the...
) chambers that are used to conduct experiments like XPS
X-ray photoelectron spectroscopy
X-ray photoelectron spectroscopy is a quantitative spectroscopic technique that measures the elemental composition, empirical formula, chemical state and electronic state of the elements that exist within a material...
, UPS
Ultraviolet photoelectron spectroscopy
Ultraviolet photoelectron spectroscopy refers to the measurement of kinetic energy spectra of photoelectrons emitted by molecules which have absorbed ultraviolet photons, in order to determine molecular energy levels in the valence region.-Basic Theory:...
, LEEM
Low-energy electron microscopy
Low-energy electron microscopy, or LEEM, is an analytical surface science technique invented by Ernst Bauer in 1962, however, not fully developed until 1985. LEEM is a technique used by surface scientists to image atomically clean surfaces, atom-surface interactions, and thin films...
and NEXAFS.
Usually in every beamline
Beamline
In particle physics, a beamline is the line in a linear accelerator along which a beam of particles travels. It may also refer to the line of travel within a bending section such as a storage ring or cyclotron, or an external beam extracted from a cyclic accelerator.In materials science, physics,...
there are other analytical tools such as, a MS
Mass spectrometry
Mass spectrometry is an analytical technique that measures the mass-to-charge ratio of charged particles.It is used for determining masses of particles, for determining the elemental composition of a sample or molecule, and for elucidating the chemical structures of molecules, such as peptides and...
or a GC-MS
Gas chromatography-mass spectrometry
Gas chromatography–mass spectrometry is a method that combines the features of gas-liquid chromatography and mass spectrometry to identify different substances within a test sample. Applications of GC-MS include drug detection, fire investigation, environmental analysis, explosives investigation,...
. These techniques help supplement and better quantify the experiments carried out at the end station.
Nobel prize
In 2003, Roderick MacKinnonRoderick MacKinnon
Roderick MacKinnon is a professor of Molecular Neurobiology and Biophysics at Rockefeller University who won the Nobel Prize in Chemistry together with Peter Agre in 2003 for his work on the structure and operation of ion channels....
won the Nobel Prize in Chemistry
Nobel Prize in Chemistry
The Nobel Prize in Chemistry is awarded annually by the Royal Swedish Academy of Sciences to scientists in the various fields of chemistry. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895, awarded for outstanding contributions in chemistry, physics, literature,...
for deciphering the structure of neuronal ion channel
Ion channel
Ion channels are pore-forming proteins that help establish and control the small voltage gradient across the plasma membrane of cells by allowing the flow of ions down their electrochemical gradient. They are present in the membranes that surround all biological cells...
, his work was in part conducted at the NSLS.
User statistics
The National Synchrotron Light Source hosts more than 2,200 users from 41 U.S. states and 30 other countries every year. Just in 2009, there were 658 journal publications and 764 total publications including; journal publication, books, patents, thesis, and reports.NSLS-II
Between 2013 and 2015, the NSLS will be phased out of operation after more than 30 years of service. It will be replaced by the NSLS-II, which is designed to be 10,000 times brighter.See also
- SynchrotronSynchrotronA synchrotron is a particular type of cyclic particle accelerator in which the magnetic field and the electric field are carefully synchronised with the travelling particle beam. The proton synchrotron was originally conceived by Sir Marcus Oliphant...
- Synchrotron radiationSynchrotron radiationThe electromagnetic radiation emitted when charged particles are accelerated radially is called synchrotron radiation. It is produced in synchrotrons using bending magnets, undulators and/or wigglers...
- List of synchrotron radiation facilities