In 2009, the Linac Coherent Light Source (LCLS) made waves in the scientific community by producing X-ray pulses a billion times brighter than any other source. This remarkable tool allows scientists to capture ultrafast snapshots of the invisible world, imaging molecules and atoms as they change over time. However, the LCLS is limited to 120 pulses per second. To push the boundaries of exploration further, scientists are developing the LCLS-II, which promises to deliver a beam 8,000 times brighter, operating at an astonishing one million pulses per second.
Located in a national laboratory, the LCLS is the world’s first hard X-ray free electron laser. It uses a particle accelerator to generate extremely bright electron beams, which are then transformed into powerful X-ray laser pulses. This process involves ultraviolet lasers targeting copper to create electron pulses, which are accelerated using klystrons—devices akin to microwave ovens. As electrons pass through magnets, they emit X-rays, which can be focused on various samples, capturing them in femtosecond-long pulses. This allows scientists to track atomic motion, creating “molecular movies” that reveal chemistry in action, study protein structures for drug development, and image quantum materials with unprecedented clarity.
While the original LCLS excelled in observing molecular structures, researchers sought a machine capable of even faster operations. Enter the LCLS-II, a superconducting accelerator designed to produce intense X-ray bursts at a high repetition rate. By increasing the pulse rate from 120 to one million pulses per second, the LCLS-II will significantly enhance scientific output. This advancement will allow scientists to explore energy flow through various states in a system, providing deeper insights into atomic and molecular physics.
The LCLS-II’s superconducting accelerator will feature 37 cryo modules, each containing eight niobium cavities. These cavities achieve superconductivity when cooled with liquid helium to just above absolute zero, eliminating electrical resistance and enabling continuous operation. This technological leap allows the LCLS-II to achieve its remarkable pulse rate, offering unprecedented opportunities for scientific exploration.
Installing the cryo modules in a narrow underground tunnel presents significant challenges. Each module is approximately 40 feet long, and they are configured in three different arrangements. Despite these challenges, the installation is nearly complete. The LCLS-II will also feature new undulators, creating magnetic fields far stronger than Earth’s, further enhancing its capabilities.
Once operational, the LCLS-II will produce more X-ray pulses in a few hours than the LCLS has over its entire lifetime, generating terabytes of data each second. This immense power will lead to groundbreaking discoveries, allowing scientists to map molecular disintegration and examine energy flow in quantum materials. The LCLS-II will complement the existing LCLS, with each machine exploring different states of matter at varying X-ray regimes.
The development of LCLS-II comes at a pivotal time in X-ray science. It will provide capabilities unmatched by any other facility, enabling scientists to tackle new and challenging fields. By harnessing this new superconducting source, researchers are poised to make transformative discoveries, pushing the boundaries of what is possible in chemistry, biology, and physics.
Explore the Linac Coherent Light Source facility through a virtual tour. Familiarize yourself with the layout, key components, and the technology behind the world’s first hard X-ray free electron laser. Reflect on how each part contributes to the overall function of the LCLS.
Engage with an interactive simulation that demonstrates how X-ray pulses are generated using a particle accelerator. Experiment with different parameters to see how they affect the brightness and frequency of the X-ray pulses. Discuss your findings with peers.
Participate in a group discussion about the superconducting technology used in the LCLS-II. Analyze the benefits and challenges of using superconducting accelerators and how they enhance the capabilities of X-ray lasers. Share insights on potential future applications.
Review case studies where “molecular movies” have been used to study chemical reactions. Analyze how these studies have contributed to advancements in drug development and material science. Present your analysis to the class, highlighting key discoveries.
Conduct a research project on potential future applications of X-ray science with the advent of LCLS-II. Investigate how this technology could revolutionize fields such as quantum physics, biology, and energy research. Present your findings in a written report or presentation.
Here’s a sanitized version of the provided YouTube transcript:
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This is the world’s brightest X-ray laser. At the time of its first light in 2009, the Linac Coherent Light Source (LCLS) generated X-ray pulses a billion times brighter than anything around. The LCLS is a tool unlike anything before it. We can deliver these pulses of X-rays in one millionth of one billionth of a second. This large machine allows scientists to take ultrafast snapshots of the invisible world, imaging molecules and atoms, and documenting how they change and evolve over time. However, the LCLS maxes out at 120 pulses per second. To explore the ultra-small world like never before, scientists and engineers are building something new. The LCLS-II will take the free electron laser field to another level. This will be unprecedented and will allow for a beam that is 8,000 times brighter than the LCLS beam, operating at one million pulses per second.
At this national lab, hidden deep underground, scientists have been conducting groundbreaking research for decades. The entire tunnel and building are about three kilometers long, and the original project utilized that full length. Currently, the LCLS accelerator is in the final kilometer. The LCLS, short for the Linac Coherent Light Source, is the world’s first hard X-ray free electron laser. It uses a particle accelerator to fire extremely bright electrons to create fast pulses of hard X-rays, which is why it is called an X-ray laser.
In the 1990s at SLAC, researchers figured out how to turn those super bright electron beams into very intense and powerful X-ray laser pulses. We have ultraviolet lasers aimed at a piece of copper, pulsing that optical laser about 100 times a second to create an electron pulse. These electron pulses are channeled into the accelerator, which uses a technology called klystrons. We can think of them as microwave ovens that accelerate these electrons. As we accelerate the electrons, the LCLS operates using devices called undulators. When an electron passes through magnets, it bends and emits X-rays. We can then focus the X-rays into various sample materials, whether that sample is an amino acid, graphene, or supercooled water, capturing them in time with strobe-like pulses lasting just a few femtoseconds. A femtosecond is a quadrillionth of a second, or one millionth of one billionth of a second. This time scale allows scientists to track atomic motion, enabling researchers across disciplines to explore the far reaches of scientific knowledge. It empowers them to create “molecular movies” that show chemistry in action, study the structure and motion of proteins for next-generation drugs, and image quantum materials with unprecedented resolution. It is a tool for exploration, allowing for transformational science in chemistry, biology, and physics.
The LCLS-I, the original build, was excellent for observing how molecular structures evolve over time using bright X-rays. However, researchers wanted to go beyond just looking at molecular structures and desired a machine that could operate even faster. The LCLS-II accelerator is a superconducting accelerator designed to produce intense bursts of X-rays at a very high repetition rate, far exceeding its predecessor. This new accelerator will increase the pulse rate from 120 pulses per second to one million pulses per second. More shots per second allow for the collection of more information in a shorter time, enhancing scientific output. But it’s not just about quantity; it’s also about what we can observe with the LCLS-II. While LCLS-I focuses on structure, LCLS-II will allow us to examine how energy flows through various states in a system.
The LCLS-II will be able to image atoms, molecules, and subatomic interactions at greater resolutions thanks to its superconducting accelerator. For LCLS-II, we will be installing 37 cryo modules, each roughly 12 meters long and containing eight accelerating cavities. These new niobium cavities are superconducting, and we achieve superconductivity by cooling them with liquid helium, just two degrees above absolute zero, where all motion theoretically stops. This ultra-cool upgrade is a significant change from the LCLS, which uses a copper accelerator and operates at room temperature. Superconductors, when cooled sufficiently, exhibit no electrical resistance, allowing for continuous operation. This enables the jump from 120 pulses per second to one million pulses per second.
However, installing 37 twelve-meter-long cryo modules inside a narrow underground tunnel nine meters below ground is a challenging task. This is a cryomodule, approximately 40 feet long, and we string them together in three different configurations. The installation is currently about 95 percent complete in the tunnel. In addition to the new superconductive accelerator, LCLS-II will also feature new undulators that will create magnetic fields tens of thousands of times stronger than Earth’s magnetic field.
We are currently in the TMO instrument hutch, one of the first stops for the LCLS-II superconducting beam when it becomes operational. This instrument is designed to examine the dynamic properties of energy transfer between states. Once operational, the new accelerator will produce more X-ray pulses in a few hours than the LCLS has generated over its entire lifetime, generating terabytes of data each second. This new power will undoubtedly lead to an influx of breakthroughs and discoveries. By scanning through time, we can map how molecules break apart, providing insights into fundamental atomic and molecular physics. Another aspect involves examining how energy flows through quantum materials.
Despite the exciting potential of this new accelerator, the LCLS will remain operational. The LCLS-II will complement the existing LCLS. The two machines will work together, with LCLS operating in a harder X-ray regime and LCLS-II providing softer or tender X-rays, allowing for the exploration of different states of matter at a much higher repetition rate. The new accelerator will take over the first kilometer of the tunnel, while the original will remain in its current position at the end. The LCLS-II is on track to achieve “first light” in summer 2022. It is exciting to work on a machine that will significantly aid scientists in making groundbreaking discoveries.
One of the most important aspects of large scientific experiments is planning for the future. LCLS-II is being developed at a crucial time in X-ray science. It will provide groundbreaking capabilities and address areas that cannot be explored at any other facility. With this new source enabling much more science, we aim to tackle new, challenging scientific fields, moving beyond simply improving existing experiments. We are committed to utilizing this new superconducting source to its fullest potential.
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This version removes any informal language and maintains a professional tone while conveying the same information.
X-ray – A form of electromagnetic radiation with a very short wavelength, capable of penetrating most substances, often used for medical imaging and material analysis. – The use of X-ray diffraction allowed the researchers to determine the crystal structure of the new compound.
Laser – A device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. – The laser was used to precisely measure the distance between the satellite and the Earth’s surface.
Superconducting – Referring to a material that can conduct electricity with zero resistance below a certain temperature. – The superconducting magnets are crucial for the operation of the Large Hadron Collider.
Electrons – Subatomic particles with a negative charge, found in all atoms and acting as the primary carrier of electricity in solids. – The flow of electrons through the conductor is what generates an electric current.
Molecules – Groups of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. – The study of water molecules is essential for understanding many biological processes.
Atoms – The basic units of matter and the defining structure of elements, consisting of a nucleus surrounded by electrons. – By understanding the arrangement of atoms in a material, scientists can predict its properties and behavior.
Pulses – Short bursts of energy, often used in the context of light or sound waves. – The laser emitted pulses of light that were used to map the surface of the planet.
Physics – The natural science that studies matter, its motion and behavior through space and time, and the related entities of energy and force. – The principles of physics are fundamental to understanding how the universe operates.
Chemistry – The branch of science concerned with the substances of which matter is composed, the investigation of their properties and reactions, and the use of such reactions to form new substances. – Chemistry plays a crucial role in developing new materials and pharmaceuticals.
Discovery – The act of finding or learning something for the first time, often leading to new knowledge or understanding in science. – The discovery of the Higgs boson was a significant milestone in particle physics.
