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Nov 4, 2000 16th CAARI 1
The Nobel Laboratory Experiments Revisited
Richard J. Smith
Physics Department
Montana State University
Bozeman MT 59715
Nov 4, 2000 16th CAARI 2
Introduction
What is the Nobel Laboratory Series
of experiments? Format and content of some NLS labs Observations of what has worked and
changes made in past 10 years Some new experiments and the future
Nov 4, 2000 16th CAARI 3
The Nobel Laboratory Series
Upper division laboratory Experiments based on recent Nobel prize-
winning work Major new equipment purchased through
the NSF-ILI program (1990) Take advantage of department “experts” in
various research areas
Nov 4, 2000 16th CAARI 4
The NLS Experiments
High Temperature Superconductivity– (K.A. Muller and J.G. Bednorz 1987)
Scanning-Tunneling Microscopy– (G. Binnig and H. Rohrer 1986)
Nuclear Reactions and Nucleosynthesis– (W.A. Fowler 1983)
Electron Spectroscopy– (K.M. Siegbahn 1981)
Nov 4, 2000 16th CAARI 5
The NLS Experiments - cont.
Non-linear Optics– (N. Bloembergen 1981)
Laser Spectroscopy – (A. L. Schawlow 1981)
Magnetism and the Quantum Nature of Solids– (J.H. Van Vleck, N.F. Mott, P.W. Anderson 1977)
Nov 4, 2000 16th CAARI 6
Nuclear Reactions and Nucleosynthesis
Experiment: Study the nuclear reactions
Li7(p,)He4 and F19(p,)O16
Physics: collision kinematics, reaction cross section, energy loss for ions in solids and energy straggling, resonant reactions
Equipment: 2MV van de Graaff accelerator, solid state particle detectors, pulse counting electronics and MCA, vacuum hardware
Nov 4, 2000 16th CAARI 7
MSU Ion Beam Laboratory
Nov 4, 2000 16th CAARI 8
2 MV van de Graaff Accelerator
Nov 4, 2000 16th CAARI 9
NRA and RBS Target Chamber
Nov 4, 2000 16th CAARI 10
NLS Experiments: Format
Example: Nuclear Reactions Lab Week 1: Introductory lectures (2 or 3)
– Students run a “calibration” experiment to become familiar with the equipment; reading and homework
– Example: 210Po source and Al stopper foil
Nov 4, 2000 16th CAARI 11
NLS Experiments: Format
Example: Nuclear Reactions Lab Week 2: All students run a standard
experiment– Ex: study the kinematics of the p, reaction in a
LiF target at one scattering angle and two different accelerator beam energies
– get familiar with operation of the van de Graaff accelerator and data analysis
Nov 4, 2000 16th CAARI 12
NLS Experiments: Format
Example: Nuclear Reactions Lab Weeks 3&4: Expand the standard experiment
or carry out a new experiment– Ex: Measure the reaction cross section for the F
resonance; measure the dependence of the reaction products on incident kinetic energy for F- and Li- derived ’s
– oral presentations in class
Nov 4, 2000 16th CAARI 13
Comments: Things that work well
4-hour lab session each week Open-ended experiments Opportunity for student design of experiment Oral presentations in Weeks 2, 3, and 4 Weekly, short written reports Occasional long, complete reports Groups of 2 or 3 students
Nov 4, 2000 16th CAARI 14
…More things that work well
Lab manuals tailored to our experiments 4 experiments per semester (4 weeks each) Access to department experts Support for other programs
– high-school teachers (STIR)– 2- and 4-year faculty enhancement workshops (2)– MS in Science Education for high-school teachers– Senior Capstone projects
Nov 4, 2000 16th CAARI 15
Comments: Things that need fixing
Safety in the lab “Too much work” for a 2-credit course “Too much software”: PC instrumentation Limited design experience for students Too expensive for small department
NSF: $90K; MSU: $90K; Physics $30K More faculty involvement High maintenance costs (optics,vacuum hdwr)
Nov 4, 2000 16th CAARI 16
Acknowledgements
People: Robert J. Swenson
John Carlsten
Rufus Cone
John E. Drumheller
Gerald J. Lapeyre
Hugo Schmidt
Richard J. Smith
Students and visitors
Funding: NSF Grant No. DMR-8952165
Nov 4, 2000 16th CAARI 17
Examples of Student Projects
STM study of Au particles on graphite STM study of ion impact craters on graphite ERDA for hydrogen analysis in Ti-Mo alloys AES analysis of S-O interaction on Ti surfaces
Nov 4, 2000 16th CAARI 18
Significant changes in recent years
Drop the experiments using high power lasers– safety and damage to optical components
Increase course credit to 4 semester credits Add more optics labs Initiation of capstone experience at MSU
Nov 4, 2000 16th CAARI 19
New experiments
Gaussian Beam Propagation Longitudinal Modes of He-Ne Laser Index of Refraction of Gases using
an Acousto-optic Modulator Pockels effect using Frequency Doubling
Electro-optic modulation (KD2PO4)
Nov 4, 2000 16th CAARI 20
New experiments: Pockels Effect
Reference: “Frequency doubling electro-optic modulation system for Pockels effect measurements: application in LiNbO3”,
N.G. Theofanous et al., Rev. Sci. Instrum. 68 (5) May 1997
Modified for KD2PO4
Nov 4, 2000 16th CAARI 21
Pockels Effect using FDEOM
Nov 4, 2000 16th CAARI 22
Pockels Effect using FDEOM
Waveforms on and off the frequency doubling position