Demonstrations by CAMD staff at Bethany High
CAMD research staff members were invited by the Bethany Christian High School in Baker on February 28, 2008 to participate in a “Science Day.” The CAMD team consisted of John Scott, Scientific Director, and researchers Kyungmin Ham, Ronnel Jiles, Selim Kazan, Eric Knott, Toby Miller, and Varshni Singh. The purpose of this community outreach effort was to acquaint young science students about the scientific activities at CAMD.
CAMD’s presentation included lectures, talks, demonstrations, and experiments. Forty-eight 11th and 12th graders participated in the activities; of these, 20 were from Advanced Chemistry and 28 were from Advanced Physics. Science teachers Kathy Moise and Jesse Moland also participated in the activities. The CAMD visit was a follow-up from an earlier visit by Bethany High students to CAMD in December last year.
“Does the mass of an electron remain constant when accelerated to near the speed of light?” John Scott and Toby Miller dealt with fundamental questions such as this in an attempt to explain relativistic mass and how Einstein in the early 20th century had dealt with this seeming anomaly by interpreting physics with a new theory of relativity. The effects of relativity on synchrotron radiation produced by CAMD’s electron storage ring, covering the spectral range from the far-infrared to the hard-X-ray region, were also discussed. Experiments to demonstrate the validity of such observations were conducted that included measurements of the accelerating voltage, homogeneous magnetic field, and the radius of the accelerated electron beam in an experiment done in the classroom using non-relativistic electrons. The results were compared with the same measurements made on the electrons in the CAMD storage ring.
X-ray Microtomography experiments at CAMD utilize the bright beam of hard X rays generated in the storage ring. Kyungmin Ham discussed the high-resolution 3-D images produced by shining narrow spectral bands of X rays through opaque objects such as fossils and honeycombs. Bethany High students caught their first glimpses of an X-ray microscopic 3-D image of a rotating single bee-hive cell with a harmful mite crawling around a bee larva.
X-ray-based Microfabrication is a much-used technology at CAMD. X-ray LiGA is an acronym for a process that uses X rays to make lithographic micron-feature-sized images in polymers, followed by electroplating metals into features formed in the polymers and, ultimately, using the resulting metal microstructures as an embossing tool to hot emboss the features into resins. Varshni Singh described the LiGA process and showed micrographic pictures of some of the structures manufactured at CAMD. Varshni and Johannes Beuerle then directed the students on how to use a “Scope-on-a Rope,” a hand-held electronic camera microscope, to examine the structures and compare sizes with hairs on their arms.
A vacuum chamber is an important component of the CAMD synchrotron light source. Members of the CAMD Vacuum/Mechanical group, Ronnel Jiles, Eric Knott, and Selim Kazan, explained why vacuums are crucial for allowing electron beams to travel through space. Eric delivered a slide presentation that provided the students with salient points related to atmospheric pressure and the history of vacuum technology. A comparative experiment, demonstrating the difference in the speeds of two ping-pong balls falling separately through two clear long plastic tubes, one evacuated by a vacuum pump and the other non-evacuated, was conducted to prove the point. The physics of vacuum and air pressure was also demonstrated through the “vacuum gun,” effects of high vacuum on a ringing alarm clock, and the impact it had on a humble marshmallow by the removal and the re-injection of air into a chamber containing the marshmallow.
The visit also included good food (lunch at the courtesy of Bethany High) and good conversation in the form of a lively and productive exchange of ideas and information between the students and the CAMD staff.
