By Alex Solomon.
Pietro F. Pasqua Fellow and Associate Professor Maik Lang and graduate students Alex Solomon and Evan Williams traveled to the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany. Once there, they did just that: heavy ion research. The students are part of the Disordered Materials (DISMAT) Group, led by Lang.
“The experiment we performed utilized a synchrotron accelerator which produced uranium ions with extremely high energies of 60 GeV, or about 60 percent of the speed of light,” said Solomon. “These uranium ions bombard both macroscopic single-crystal samples and microscopic polycrystal samples. The latter were maintained at extremely high pressure (500,000 atm); normal atmospheric pressure is 1 atm) while RAMAN spectroscopy was used to observe changes in the crystallinity of the samples under these extreme environments.”
However, there was also time for cultural activities while being in Germany.
At a Glance
Here we are shown in front of the gate entering the GSI complex, which will soon undergo some restructuring (one of the largest research projects worldwide) and will be renamed FAIR (Facility for Antiproton and Ion Research). Upon arriving at the GSI Helmholtz facility, we were given a tour of the GSI complex.
During our time at GSI, we were able to tour the facility and learn about their many labs. We saw a wealth of accelerator technologies in action, starting with the linear accelerator that was responsible for the first creation of elements Bohrium (107) through Copernicium (112).
Our tours extended to the detector laboratory, which has produced advanced instrumentation for the detection of new particles at both GSI and CERN. In the detector laboratory we were shown the large clean room where nano-thickness semiconductors and high spatial resolution ionization chambers are used to fabricate many of the world’s premier particle detectors.
In this image, I am looking at the beamline controls and monitor. Each bunch contains approximately 100,000,000 ions, providing a sufficient particle flux to extensively modify our samples.
This photo shows me demonstrating the secure entry process that must be used due to the use of radiation. The extremely high energies used allowed us to fully penetrate crystal samples with millimeter thicknesses.
As the heavy uranium ions are slowed from 60 percent of the speed of light to a halt, they impart massive amounts of energy to the crystals, changing them significantly. The research group we were with focuses on understanding the interaction of these heavy, fast ions with materials. Once these samples are no longer radioactive, we will characterize their structural modifications using domestic synchrotron X-ray light sources (electron accelerators).
Upon arriving in Germany, we traveled to the romantic town of Heidelberg, nestled in a valley along the Neckar River, about an hour south from the accelerator facility. There, we explored the local cuisine and springtime scenery before setting off for our experiment.
Accelerator technologies are always advancing, with new facilities expanding on their predecessors to explore higher energy physics. The FAIR site is one such example. Here we stood atop the construction site of the massive synchrotron accelerator that will be used for antimatter experiments.
Here, Williams is shown adjusting the output frequency utilized to count the numerous ions imparted on the samples.
After the conclusion of a successful experiment, we spent our remaining time in Germany visiting the cities and the countryside, which is riddled with castles spanning one millennium of European history.