Engineering and Accelerator Division
The Engineering and Accelerator Division is responsible for the operation, maintenance and for the improvements and upgrades of the LNLS synchrotron light source and support facilities. It plays an important role in the project and construction of beamlines and experimental stations for the light source. The Division is also responsible for the infrastructure projects of the LNLS facilities.
Since its inception in 1987 it has been one of the main missions of the LNLS to develop in Brazil the technical expertise to project and construct particle accelerators for the production of synchrotron light for scientific research. In 1997 the first synchrotron light facility to operate in the southern hemisphere was delivered to the scientific community. In this ten year period the LNLS was able to train a technical team that not only designed and built most of the systems that comprise the light source but that has also been continuously improving the facility since then.
As the experiments performed by the users in the beamlines become more and more complex and challenging it is essential to keep the light source in line with the new demands. Upgrades and improvements have been part of the LNLS synchrotron light source’s operational scenario since it started operating as an open facility. These upgrades have improved the range of applicability of the source considerably, either by extending the range of photon energies made available for users or by improving the quality of the photon beam delivered to the beamlines.
The most comprehensive upgrade of the storage ring was undoubtedly the installation of the booster synchrotron in 2002. In order to improve beam orbit stability an overall replacement of the storage ring beam position monitors was carried out in 2008 and 2009. The installation of insertion devices – special magnets designed to extend the photon flux in certain energy ranges – required modifying the machine’s magnetic optics to keep beam lifetime at the same level and simplify operating procedures. Several other small scale improvements have been implemented along these years, the last one being the replacement of the entire klystron-based RF amplification chain by a set of new solid-state amplifiers built in the lab and put into operation in 2010.
The LNLS light source is a second generation machine, meaning that most of its beamlines use the synchrotron light emitted in the dipoles. However, in the few free straight sections between dipoles it is possible to install special magnetic devices called insertion devices. By producing a wiggle in the orbit of electrons, these devices induce the emission of light with different features from those produced in the dipoles, allowing to extend the energy range of the photons and to increase the photon flux in the energy of interest. In this context another major achievement was the construction of the PGM beamline, a challenging undertaking that involved several groups of the Accelerator and Engineering Division and highlighted the importance of tight resource management to carry out complex projects. For this beamline a special insertion device, an EPU Undulator, was thoroughly projected and built at the LNLS workshops and it is now installed in the storage ring. Two other insertion devices are installed in the storage ring, enabling a new class of experiments that were impossible or difficult to perform in the dipole beamlines.
Despite the high reliability and beam stability, the current source has several limiting factors that prevent its use in a large number of applications of extreme importance for future developments in science and technology. Among these limitations are the low energy and the very large size and divergence (emittance) of the electron beam. These limitations have large impact on the brightness of the source, limitations that are impossible to overcome for the current storage ring. The state of the art light sources have very small emittance and operate at higher electron energy and current. These third generation machines use preferentially insertion devices as photon sources and are much brighter photon sources.
To overcome these limitations, the technical groups of the Division are now involved in the design and project of the LNLS next light source SIRIUS, a very low emittance third generation machine. The new project presents several technological challenges and will open up a whole range of new research possibilities for the user community.
