The Continuous Electron Beam Accelerator Facility (CEBAF) at the U.S. Department of Energy's Thomas Jefferson National Accelerator Facility has achieved the final two accelerator commissioning milestones needed for approval to start experimental operations following its first major upgrade.
In the early hours of May 7, the machine delivered its highest-energy beams ever, 10.5 billion electron-volts (10.5 GeV) through the entire accelerator and up to the start of the beamline for its newest experimental complex, Hall D. Then, in the last minutes of the day on May 7, the machine delivered beam, for the first time, into Hall D.
In addressing staff, Jefferson Lab Director Hugh Montgomery praised the efforts of the many Jefferson Lab staff members who made the accomplishment a reality, “It's really appreciated the way you have worked together and, in particular, the safe way in which you have pulled this off,” he said.
The CEBAF accelerator is based on superconducting radiofrequency (SRF) technology and produces a stream of charged electrons that scientists use to probe the nucleus of the atom. CEBAF was the first large-scale application of SRF technology in the U.S., and it is the world's most advanced particle accelerator for investigating the quark structure of the atom's nucleus. CEBAF was originally designed to operate at 4 GeV, and it reached 6 GeV, or 6 billion electron volts in its original configuration.
The 12 GeV Upgrade is a $338 million project to double CEBAF's maximum operational energy and includes the construction of the fourth experimental hall, as well as upgrades to equipment in the existing halls.
On May 7, 10.5 GeV beam was delivered to the Hall D Tagger Facility, which converts CEBAF's electron beam into photons that will be used for experiments in Hall D. To deliver the beam to the Tagger Facility, operators steered it through a newly installed beamline that rises 5 meters, more than 16 feet, as it approaches the Tagger Facility.
"With this accomplished, the beamline elements from the photocathode that generates the electrons through 5.5 passes of the CEBAF racetrack and the new Hall D electron beamline have gloriously transported beam!" said Arne Freyberger, Accelerator Operations manager. "This is not luck. This is a direct reflection of the quality of the staff."
Leigh Harwood, 12 GeV Upgrade project lead for Accelerator, concurred, "The 12 GeV Upgrade project team thanks you for your dedication and the hard work that got us to this moment."
In addition to setting a new energy record for beam in CEBAF, these significant accomplishments complete two of the major 12 GeV Project milestones necessary for Jefferson Lab to be granted the next DOE approval step, Critical Decision-4A (Accelerator Project Completion and Start of Operations).
These two accomplishments build on others. On Feb. 5, accelerator operators sent streams of electrons around the CEBAF accelerator once and achieved full upgrade-energy acceleration of 2.2 GeV in one pass. Then they ran the accelerator at this specification for the next eight hours, achieving 50 percent availability on their first run of the machine at design specifications. On April 1, the CEBAF accelerator delivered electron beams into a target in an experimental hall, recording the first data of the 12 GeV era. The machine sent electrons around the racetrack three times (known as “3-pass” beam), resulting in 6.11 GeV electrons at 2 nanoAmps average current for more than an hour. On May 3, the first beam, with energy of 6.18 GeV, was delivered to the front section of the beamline to Hall D, thus demonstrating that all 5.5 passes of the accelerator were functional and there were no obstructions in the way of the beam. With 5.5 passes functional, CEBAF energy was scaled to 10.5 GeV to achieve these last two milestones.
DOE approval of Critical Decision 4A will permit accelerator operators to continue commissioning the accelerator in order to achieve full 12 GeV energy and to send electron beams to Jefferson Lab's experimental halls for commissioning and the start of experiments.
Jefferson Science Associates, LLC, a joint venture of the Southeastern Universities Research Association, Inc. and PAE Applied Technologies, manages and operates the Thomas Jefferson National Accelerator Facility, or Jefferson Lab, for the U.S. Department of Energy's Office of Science.
DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.
Contact: Kandice Carter, Jefferson Lab Public Affairs, 757-269-7263, firstname.lastname@example.org
Kandice Carter | Eurek Alert!
Knots in chaotic waves
29.07.2016 | University of Bristol
International team of scientists unveils fundamental properties of spin Seebeck effect
29.07.2016 | Johannes Gutenberg-Universität Mainz
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
29.07.2016 | Event News
15.07.2016 | Event News
15.07.2016 | Event News
29.07.2016 | Power and Electrical Engineering
29.07.2016 | Life Sciences
29.07.2016 | Event News