Researchers develop new identification device for heavy ion particles

A scientific team at Michigan State University’s (MSU) Center for Rare Isotope Beams (FRIB) has developed a new optical detector. This development will allow scientific users to help generate new knowledge and advances in nuclear physics. The team’s findings are detailed in an “Editor’s Pick” article published in Review of scientific instruments.

The Energy Loss Optical Scintillation System (ELOSS) represents a breakthrough in both instrumentation and experimental capabilities. nuclear physics. The new detector allows researchers to study isotopes at high beam speed and high throughput.

“In experimental physicsInnovation and breakthroughs have always been closely related to improving accelerator and collider technologies,” said Marco Cortesi, Detector Systems group leader at FRIB and ELOSS project leader.

“Modern powerful machines demand the development of innovative detectors capable of taking advantage of the new capabilities of the beam. FRIB is a new accelerator technology with impressive discovery potential. Now, we have also improved the detection equipment to advance and strengthen the ambitious scientific program in FRIB”.

The team included Cortesi; Alexandra Gade, professor of physics at the FRIB and the Department of Physics and Astronomy at MSU and deputy director of science at the FRIB; Remco Zegers, professor of physics at FRIB and in the MSU Department of Physics and Astronomy; Jorge Pereira, staff research physicist; Daniel Bazin, research professor; Steve Lidia, Manager of the Beam Measurement and Instrumentation Department; Joe Asciutto, diagnostic engineer; and Sean Dziubinski, FRIB Graduate Assistant.

For decades, researchers have used a conventional ionization chamber to identify the atomic numbers of heavy ions using an energy loss measurement. The FRIB researchers, however, broke with tradition. Instead, they measured the light produced along the track with their optical ionization camera at the focal plane of the S800 spectrograph at FRIB.

The multi-segmented optical detector is filled with xenon gas at pressures ranging from 400 to 800 Torr, a range close to atmospheric pressure. Photomultiplier tube arrays, standard tools for light detection, surround the gas and are positioned along the beam direction to record the scintillation light. The number of detected photons is proportional to the energy deposited by the beam particle along its path in the effective volume of the detector. This allows scientists to identify the corresponding atomic number.

The ELOSS method offers several technical advantages compared to conventional load reading systems. The team discovered that ELOSS can measure the power loss of heavy ions with almost three times better resolution and 10 times the count rate, or the speed at which measurements can be taken.

“This saves time by enabling faster experiments and empowering researchers to collect more statistics at a faster rate,” Cortesi said. “It also opens up opportunities for new experiments.”

Dziubinski, a doctoral student in physics, played a leading role in the effort. In addition to working on mounting and calibrating the detector, Dziubinski also created a benchtop method for performing the calibration, which Cortesi considered critical to the success of the project.

“I’ve been building and running experiments the entire time I’ve been at MSU,” Dziubinski said. “Working on the ELOSS project has given me constant exposure to new tools and concepts in physics.”

Cortesi sees the involvement of student researchers like Dziubinski as crucial to the long-term advancement of the field. By training a new generation for detector research and development, he said, researchers can better harness the power of FRIB’s accelerator technology and pursue cutting-edge physics with greater efficiency and vigor.

“ELOSS is an upgrade to improve particle identification, and more will come,” Cortesi said. “We want to take advantage of the opportunities that FRIB offers. We can do it with this new detector.”