The Brazilian Center for Research in Energy and Materials (CNPEM), an organization supervised by the Ministry of Science, Technology and Innovation (MCTI), announces the opening of the seventh regular call for research proposals at Sirius, the fourth-generation synchrotron light source operated by the National Synchrotron Light Laboratory (LNLS).

Sapoti (Scanning Analysis by PtychO for Tomographic Imaging) is one of the two experimental stations of the Carnaúba beamline at Sirius. The facility is one of the most sophisticated and challenging stations ever developed at the Brazilian accelerator. Its goal is to achieve resolutions on the order of 1 nanometer in coherent X-ray imaging and tomography, a performance that places it among the world's most precise instruments in synchrotron light-based microscopy.  

The experimental stations of the Carnaúba beamline

The Carnaúba beamline operates in the 2.05 to 15 keV energy range, and was designed to perform simultaneous measurements with multiple X-ray analytical techniques, including diffraction, spectroscopy, fluorescence, and luminescence, as well as two- and three-dimensional imaging. It is the longest line at Sirius and uses a highly bright beam from an undulator, exploring the full potential for coherence and intensity that a fourth-generation synchrotron light source can provide.

[caption id="attachment_72828" align="aligncenter" width="800"] Part of the Carnaúba beamline’s infrastructure at Sirius. The beamline features two experimental stations located 136 and 142 m from the X-ray source, a vertically polarized undulator.[/caption]

Its infrastructure houses two complementary experimental stations. The Tarumã station was designed for in situ, in vivo (with plants), and cryogenic experiments, operating in an open environment with high flexibility for different types of samples. Sapoti operates in ultra-high vacuum and cryogenic conditions, which ensures even greater thermal and mechanical stability, leading to better spatial resolutions, as well as better conditions for experiments at the lower energy limit.

[caption id="attachment_72829" align="aligncenter" width="800"] The Sapoti experimental station is part of Sirius' Carnaúba beamline and will be capable of achieving resolutions of up to 1 nanometer in X-ray imaging experiments.[/caption]

Since its inception in 2018, the Sapoti station has been designed to surpass traditional resolution limits in nanoprobes — systems that focus X-rays onto nanometric points to map material properties with extremely high precision — of synchrotron light sources. To achieve this, advanced solutions in optics and highly complex mechatronics were combined. The X-ray beam, with energies from 2.05 to 15 keV, is focused by an array of Kirkpatrick–Baez (KB) mirrors capable of producing fully coherent X-ray beams with sizes between 30 and 140 nanometers.  

Unlike other systems that use refractive elements, KB mirrors offer greater efficiency and insensitivity to changes in beam energy, which is critical for spectroscopy experiments. However, they also have higher mechanical requirements — a challenge overcome through solutions developed at LNLS itself, applying advanced principles of precision engineering. 

According to Renan Geraldes, physical engineer and leader of the Mechatronics and Precision Engineering group at LNLS/CNPEM, the development of Sapoti was also an exercise in innovation and continuous learning. "From the beginning, it was expected that Sapoti would be one of the stations with the greatest technical challenges that we would have to develop”, he says. "It was a project that extracted the maximum potential from our precision mechatronics, systems engineering, and predictive design tools. Vacuum, cryogenics, optics, sample transfer and positioning — it was necessary to make it all compatible.” 

The technical challenges overcome by the Sapoti station

The Sapoti experimental station features an advanced sample positioning stage, an innovative mechatronic system developed in collaboration with the Dutch company MI-Partners. Inspired by technologies used in the semiconductor industry, the stage utilizes Lorentz actuators instead of conventional piezoelectric ones, allowing it to combine nanometer resolution with a millimeter-level range of motion. This approach makes it possible to navigate with 1 nm precision along three-dimensional trajectories with a range of up to 3 mm, something unprecedented in X-ray nanoprobes.  

Sapoti is a fully vacuum-operated station in which the KB mirrors, the sample, and some of the detectors share the same chamber. This configuration ensures improved component stability, guaranteeing greater rigidity and alignment precision while reducing absorption losses at lower energy levels.  

The station is also capable of operating under controlled cryogenic temperatures, between 100 and 300 K, conditions that not only help mitigate radiation damage but also allow for the study of frozen biological samples and sensitive materials. To achieve this, Sapoti uses a cryogenics system integrated into the stage, equipped with a cryogenic loading module with a vacuum transfer system, which allows for the insertion and manipulation of samples without exposure to air, preserving their physical and chemical properties from preparation to data acquisition.

[caption id="attachment_72830" align="aligncenter" width="533"] CARPIN sample holder, standard at the Carnaúba beamline, designed to accommodate different types of samples in micro and nanoscopy experiments at Sirius.[/caption]

To ensure versatility in handling different types of samples, Sapoti uses a standard sample holder developed especially for the Carnaúba beamline called CARPIN (CARnaúba PIN). Inspired by the OMNY PIN system, used at the Swiss Light Source (SLS) cSAXS beamline, CARPIN was designed as a universal interface capable of accommodating samples with dimensions ranging from micrometers to a few millimeters, including solid samples, liquids, pastes, powders, electron microscopy grids, and thin membranes. This flexibility facilitates the exchange of samples between different beamlines at Sirius or even other synchrotrons, expanding the possibilities for complementary or collaborative experiments. 

The Sapoti assembly involved a series of complex integration steps. Initial tests with the system in the first half of 2025 showed promising results. "Even in the initial commissioning phase, Sapoti achieved positional stability of approximately 3 nanometers, already allowing the acquisition of images with an estimated resolution of 5.5 nanometers, a performance superior to that achieved by Tarumã, even after several years of operation. As the system progresses through calibration and fine-tuning, it is expected to reach the projected limit of 1 nanometer, consolidating Sapoti among the most advanced experimental stations in the world in coherent X-ray microscopy”, Renan highlights.  

Integration with the new vertical polarization undulator

[caption id="attachment_72831" align="aligncenter" width="800"] Vertical polarization undulator of the Carnaúba beamline installed in the Sirius storage ring.[/caption]

In 2025, Carnaúba began operating with a new vertical polarization undulator (VPU), a structural advancement that significantly expands the range of experiments supported by the beamline. The new device allows access to energies below 6 keV, paving the way for obtaining spectra of light elements — such as V, Ti, Ca, S, and P — and strengthening applications in areas such as semiconductors, soil science, agriculture, biomaterials, geosciences, and environmental studies. With greater brightness at low energies and excellent coherence, VPU also increases contrast in coherent imaging of biological tissues, revealing subcellular structures that are poorly explored at higher energies.  

According to the beamline coordinator, Rodrigo Szostak, “The installation of the new undulator allows us to investigate samples with lighter elements, which are of broad interest in various fields of knowledge”. "Combining this broadened spectral range with the intrinsic characteristics of the Carnaúba beamline makes this infrastructure a powerful and unprecedented tool for studies in agriculture and geosciences, soil science, environment, and materials”, he says. Initial tests have already validated measurements of chemical elements in standard samples, and full experiments in this new energy range are planned for next year.  

There is also an important strategic aspect: very few micro and nanoscopy beamlines in 3rd and 4th generation synchrotrons operate with high performance below 6 keV, which puts Carnaúba in a unique position on the international stage. "This will be a window of opportunity for researchers to design and carry out new experiments that take full advantage of the potential of Sirius' beamlines," says Szostak.  

With its combination of high stability, cryogenics, vacuum, and state-of-the-art mechatronic control, Sapoti represents a technological and scientific leap for Sirius and for Brazil, paving the way for new frontiers in nanoscience, structural biology, and materials science.

About CNPEM

The Brazilian Center for Research in Energy and Materials (CNPEM) is home to a state-of-the-art, multi-user and multidisciplinary scientific environment and works on different fronts within the Brazilian National System for Science, Technology and Innovation. A social organization overseen by the Ministry of Science, Technology and Innovation (MCTI), CNPEM is driven by research that impacts the areas of health, energy, renewable materials, and sustainability. It is responsible for Sirius, the largest assembly of scientific equipment constructed in the country, and is currently constructing Project Orion, a laboratory complex for advanced pathogen research. Highly specialized science and engineering teams, sophisticated infrastructure open to the scientific community, strategic lines of investigation, innovative projects involving the productive sector, and training for researchers and students are the pillars of this institution that is unique in Brazil and able to serve as a bridge between knowledge and innovation. CNPEM’s research and development activities are carried out through its four National Laboratories: Synchrotron Light (LNLS), Biosciences (LNBio), Nanotechnology (LNNano), Biorenewables (LNBR), as well as its Technology Unit (DAT) and the Ilum School of Science — an undergraduate program in Science and Technology supported by the Ministry of Education (MEC). https://cnpem.br/

The Brazilian Center for Research in Energy and Materials (CNPEM), a Social Organization linked to the Ministry of Science, Technology and Innovation (MCTI), has announced the selected projects from the sixth call for proposals to conduct scientific experiments on the beamlines — as the research stations of Sirius, the largest scientific infrastructure ever built in Brazil, are called.

The Brazilian Center for Research in Energy and Materials (CNPEM), an organization overseen by the Ministry of Science, Technology and Innovation (MCTI), has opened its sixth regular call for research projects at Sirius, Brazil's fourth-generation synchrotron light source operated by the Synchrotron Light National Laboratory (LNLS).

The Brazilian Center for Research in Energy and Materials (CNPEM), a legal entity governed by private law linked to Brazilian Ministry of Science, Technology and Innovation (MCTI), and Petrobras have concluded the first phase of a technological partnership that will enable advances in exploration and expand research possibilities in oil and gas. The project basis is to use one of the research stations at Sirius, the largest and most complex scientific infrastructure in Brazil, to make 3D images of pre-salt rocks in an automated way, which is capable of quickly generating large volumes of data.

The current stored in Sirius's accelerators has increased from 100 mA to 200 mA, the result of a period of maintenance activities that involved installing new components including two superconducting radiofrequency cavities. This change represents a major advance in beamline research capabilities at Sirius. The current upgrade takes place alongside a significant change in operations from March 2023, when Sirius began to run in "top-up" mode, ensuring that current remains nearly constant throughout operations. This continuous mode increases the number of photons emitted per day and provides more stability for the accelerator components and the beamlines. Installation of the two superconducting radio frequency cavities required integrating advanced subsystems, such as implementing a cryogenic system designed to operate without consuming helium, liquefying the gas in a closed circuit and maintaining ultra-high vacuum levels in the straight sections of the ring where the cavities were positioned. The capacity for high-powered radiofrequency generation also doubled from 120 to 240 kW. [gallery size="medium" link="none" ids="71895,71896,71897"] Commissioning for the cavities included adapting the vacuum for high-power operations, adjusting dozens of control circuits and integrating the new subsystems with those already present in the accelerators (which in many cases were also updated). Despite the complexity and interdependence between the subsystems, the process was completed efficiently within the time allotted. From now on, Sirius is expected to operate at approximately 200 mA during the periods when the beamline is available to users, twice the current of previous operations. To reach the 350 mA ultimately planned for the project, new facilities will be required. "This increase in current is the result of a proportional increase in the flow of photons to the beamlines, which improves the signal-noise ratio and significantly shortens the time needed for measurements," notes Harry Westfahl Jr., Director of the Brazilian Synchrotron Light National Laboratory (LNLS).

About CNPEM

The Brazilian Center for Research in Energy and Materials (CNPEM) is home to a state-of-the-art, multi-user and multidisciplinary scientific environment and works on different fronts within the Brazilian National System for Science, Technology and Innovation. A social organization overseen by the Ministry of Science, Technology and Innovation (MCTI), CNPEM is driven by research that impacts the areas of health, energy, renewable materials, and sustainability. It is responsible for Sirius, the largest assembly of scientific equipment constructed in the country, and is currently constructing Project Orion, a laboratory complex for advanced pathogen research. Highly specialized science and engineering teams, sophisticated infrastructure open to the scientific community, strategic lines of investigation, innovative projects involving the productive sector, and training for researchers and students are the pillars of this institution that is unique in Brazil and able to serve as a bridge between knowledge and innovation. It is responsible for operating the Brazilian Synchrotron Light (LNLS), Biosciences (LNBio), Nanotechnology (LNNano), and Biorenewables (LNBR) National Laboratories, as well as the Ilum School of Science, which offers a bachelor’s degree program in science and technology with support from the Ministry of Education (MEC).

Between August and October of this year, the Sirius accelerators will undergo an important maintenance period. During these months, new components will be installed in the storage ring. By significantly increasing the photon flux to the beamlines, these changes will bring various benefits to users, such as faster experiments and higher temporal resolution.

The detector in the Sapucaia experimental station recently received its first beam of X-rays generated by the Sirius particle accelerators. This beamline, which is dedicated to small-angle X-ray scattering (SAXS), will be an important tool for studying the morphological and dynamic properties of nano and microstructured objects. 

The deadline forsubmitting proposals for the fourth call for research projects for ten Sirius beamlines has been extended until Thursday, June 27th. The extension is due to unusual systemic difficulties reported by some international users in submitting their proposals.

The Brazilian Center for Research in Energy and Materials (CNPEM), an organization overseen by the Ministry of Science, Technology and Innovation (MCTI), has released the list of scientific projects selected to be conducted within the research facilities at Sirius, Brazil's largest and most complex research infrastructure dedicated to analyzing the structure of all types of matter at the micro and nano scales.