SLAC invention makes use of terahertz radiation to energy a miniscule copper accelerator construction.
Particle accelerators generate high-energy beams of electrons, protons and ions for a variety of functions, together with particle colliders that make clear nature’s subatomic elements, X-ray lasers that movie atoms and molecules throughout chemical reactions and medical gadgets for treating most cancers.
As a rule of thumb, the longer the accelerator, the extra highly effective it’s. Now, a group led by scientists on the Division of Vitality’s SLAC Nationwide Accelerator Laboratory has invented a brand new sort of accelerator construction that delivers a 10 occasions bigger vitality achieve over a given distance than standard ones. This might make accelerators used for a given software 10 occasions shorter.
The important thing concept behind the expertise, described in a latest article in Utilized Physics Letters, is to make use of terahertz radiation to spice up particle energies.
In as we speak’s accelerators, particles draw vitality from a radio-frequency (RF) area fed into particularly formed accelerator buildings, or cavities. Every cavity can ship solely a restricted vitality increase over a given distance, so very lengthy strings of cavities are wanted to provide high-energy beams.
Terahertz and radio waves are each electromagnetic radiation; they differ of their respective wavelengths. As a result of terahertz waves are 10 occasions shorter than radio waves, cavities in a terahertz accelerator can be a lot smaller. In truth, the one invented on this research was solely zero.2 inches lengthy.
One main problem to constructing these tiny cavity buildings is to machine them very exactly. Over the previous few years, SLAC groups developed a solution to just do that. As a substitute of utilizing the standard means of stacking many layers of copper on high of one another, they constructed the minute construction by machining two halves and bonding them collectively.
The brand new construction additionally produces particle pulses a thousand occasions shorter than these popping out of standard copper buildings, which could possibly be used to provide beams that pulse at a better fee and unleash extra energy over a given time interval.
Subsequent, the researchers are planning to show the invention into an electron gun – a tool that might produce extremely shiny beams of electrons for discovery science, together with next-generation X-ray lasers and electron microscopes that may enable us to see in actual time how nature works on the atomic degree. These beams is also used for most cancers remedy.
Delivering on this potential additionally requires additional growth of sources of terahertz radiation and their integration with superior accelerators, such because the one described on this research. As a result of terahertz radiation has such a brief wavelength, its sources are significantly difficult to develop, and there may be little expertise out there at current. SLAC researchers are pursuing each electron beam and laser-based terahertz technology to supply the excessive peak powers wanted to show their accelerator analysis into future real-world functions.
Reference: “Experimental demonstration of externally pushed millimeter-wave particle accelerator construction” by Mohamed A. Ok. Othman, Julian Picard, Samuel Schaub, Valery A. Dolgashev, Samantha M. Lewis, Jeffery Neilson, Andrew Haase, Sudheer Jawla, Bruno Spataro, Richard J. Temkin, Sami Tantawi and Emilio A. Nanni, 18 August 2020, Utilized Physics Letters.
The challenge was led by SLAC’s Mohamed Othman and Emilio Nanni. The accelerator construction was designed and constructed at SLAC and examined utilizing a particular terahertz radiation supply from the Massachusetts Institute of Expertise. Different contributions got here from the Nationwide Institute for Nuclear Physics (INFN) in Italy. The challenge was funded by DOE’s Workplace of Science, together with a DOE Workplace of Science Early Profession Analysis Program award to Nanni, and the Nationwide Science Basis.