Inside The X-Ray Laser That Can Recreate A Star's Core

Two miles of lasing fun

Stanford's SLAC National Accelerator Laboratory is home to the world's largest and brightest X-ray laser, the Linac Coherent Light Source (LCLS). It's been operating since April 2009, and is in the midst of a billion-dollar upgrade that will add two new X-ray laser beams that function 8,000 times faster and 10,000 times brighter.

The entire system spans two miles—that space is used to hurl electrons down a tube and through a gauntlet of magnets, called undulators. When the electrons pass through the undulators, they're rapidly pulled back and forth. As they wiggle, they emit X-Rays. The electrons synchronize their motion as they pass through the array of magnets, causing the X-Ray light to synchronize as well. When that light is stably travelling together, or "coherent," the electrons are removed and the light is split over six different research stations.

With this technology, Stanford is able to study the nanoscale workings of the natural world by making quick, stop-motion animations. They can study photosynthesis by looking at how individual molecules move, or replicate levels of heat matched only in the core of stars.

Here's a look inside:

This image shows the portion of the LCLS that sits above ground, where the tops of the undulators are housed.
Klystrons that accelerate electrons toward the lab area sit above ground, in a building that runs the complete two miles of the LCLS.Dave Gershgorn
The LCLS's above-ground housing
The facility's above-ground housing is sparsely furnished, but highly-regulated.Dave Gershgorn
Underground, researchers in the Atomic, Molecular, and Optical Science lab ready the equipment for their next test.
Underground, researchers in the Atomic, Molecular, and Optical Science lab ready the equipment for the next test. This room is typically used for the smallest nanoscale particle research that require the highest intensity, like atoms, molecules, and even organic matter like viruses. The AMO lab is the closest to the undulators.Dave Gershgorn
The LCLS' X-Ray fires at extremely short bursts: the energy is concentrated into a millionth of a billionth of a second, or a femtosecond.
The LCLS' X-Ray fires at extremely short bursts: The energy is concentrated into a millionth of a billionth of a second, or a femtosecond. It fires this ultra-fast beam 120 times per second. By looking at matter in such short intervals of time, scientists can build stop-motion movies of things like atoms and molecules that were never possible before.Dave Gershgorn
Inside the X-Ray Pump Probe, a robotic arm is able to position the material being tested in different positions as it's being hit by the X-Ray light.
Inside the X-Ray Pump Probe, a robotic arm is able to position the material being tested in different positions as it's being hit by the X-Ray light. This chamber is optimized to study how matter changes from a solid to liquid to gas. Usually an optical laser will hit the test subject first, changing its state, then the X-Ray will quickly record an image, according to SLAC's website.Dave Gershgorn
The six experimentation chambers are separated into the Near Experimental Hall and Far Experimental Hall.
The six experimentation chambers are separated into the Near Experimental Hall and Far Experimental Hall. In between? A lot of tube.Dave Gershgorn
The halls of the LCLS are strewn with very expensive-looking and imposing equipment.
The halls of the LCLS are strewn with very expensive-looking and imposing equipment.Dave Gershgorn
The X-Ray laser is split into parallel tubing to be distributed to the Far Experimental Hall.
The X-Ray laser is split into parallel tubing to be distributed to the Far Experimental Hall.Dave Gershgorn
The paths of the X-Ray lasers slowly diverge over the course of hundreds of feet.
The paths of the X-Ray lasers slowly diverge over the course of hundreds of feet.Dave Gershgorn
To ensure that their equipment is clean, SLAC "bakes" parts of their hardware. This means they bring it up to extremely high temperatures to remove any material that could compromise the accuracy of t
To ensure that its equipment is clean, SLAC "bakes" parts of its hardware. This means workers bring the hardware up to extremely high temperatures to remove any material that could compromise the accuracy of the tests.Dave Gershgorn
It's unsafe to be in the same room as the laser during the experiment, so scientists control and monitor the proceedings from a wall of monitors just outside.
It's unsafe to be in the same room as the laser during the experiment, so scientists control and monitor the proceedings from a wall of monitors just outside.Dave Gershgorn
The Macromolecular Femtosecond Crystallography Instrument (or MFX for short), was built after an outpouring of proposals to study the processes of organic plant matter, like photosynthesis.
The Macromolecular Femtosecond Crystallography Instrument, or MFX for short, was built after an outpouring of proposals were written to study the processes of organic plant matter, like photosynthesis. It's been operational since January 2016, and can simulate a helium atmosphere.Dave Gershgorn
A joke printed on a label, stuck to a LCLS machine.
"Resistance is futile. Conductance is 1/futile."Dave Gershgorn
In the Coherent X-Ray Imaging lab, scientists concentrate the laser to be so fast that it doesn't have the time to damage sensitive biological samples
In the Coherent X-Ray Imaging lab, scientists concentrate use lenses to focus and defocus the laser beam, to avoid damaging sensitive samples.Dave Gershgorn
Large monitors give real-time readings about the current state of the LCLS
Large monitors give real-time readings about the current state of the LCLS. Researchers can see total energy, the beam's frequency, and breakdowns of each research lab.Dave Gershgorn
Scientists work inside the module of the Matter in Extreme Conditions lab, which uses the power of the X-Ray beam to emulate conditions not readily available on Earth.
Scientists work inside the module of the Matter in Extreme Conditions lab, which uses the power of the X-Ray beam to emulate conditions not readily available on Earth. The lab studies high density energy situations, only otherwise found in stars. The MEC lab has been used to study things like the creation of diamond.Dave Gershgorn

This article has been updated to reflect that the instruments pictured in the first two images are klystrons, not the tops of the undulators.