2017 May 17 - June 29
2017 October 11 - December 21
2017 Proposal deadline: 08/01/17
2017 BTR deadline: 09/10/17
The REU work mentioned below was sponsored by the
Foundation REU grant PHY-9731882. CHESS additionally sponsors outreach
work for undergraduate and graduate students seeking to broaden their
research horizons. This is, of course, over and above the very large
number of students who are trained as normal CHESS users.
Research Experiences for Undergraduates (REU)
Each year several undergraduate students do summer research at CHESS via the REU program. The REU program is a NSF-funded program for undergraduates who wish to gain research experience at major scientific facilities. Undergraduates at U.S. colleges who wish to apply for summer research at CHESS may apply via two associated REU programs:
1. The Cornell Laboratory of Elementary Particle Physics (LEPP) REU program. LEPP operates Wilson Laboratory, the parent organization of CHESS.
2. Many Cornell researchers who work at CHESS are also members of the Cornell Center for Materials Science (CCMR), and will sponsor students in synchrotron radiation-related research.
Ismail Degani, Undergraduate computer science major, has designed a remote crystal-centering software package that now allows beamline users to position protein crystals in the x-ray beam with a few clicks of the mouse. The high-resolution display uses state-of-the art streaming digital video that can be viewed on any computer console outside the experimental hutch, including remote sites. The system has been in operation during the past year. The current system is not only faster than manual positioning, but also more accurate, allowing smaller protein crystals to be rapidly positioned for structural studies.
Eric Angle, Undergraduate from Cornell University, led the design and construction of a novel high-pressure gas loading system for diamond anvil cell (DAC) specimen chambers. DACs are used to explore the properties of gases at pressures encountered deep within the outer planets, or for use as pressurization media for studies of minerals and metals deep within the earth. Loading the DAC with gases has historically been a major difficulty limiting many studies; this system overcomes this difficulty. The DAC gas loading system considerably extends capabilities in high-pressure science possible at CHESS.
Richard Clinite, as a recent Cornell Undergraduate seeking some real-world experience in physics, Rick spent the summer of 2003 working on technical upgrades to the CHESS D1 Small-angle scattering station. He successfully interfaced the ADC serial port slits with the station control software SPEC and troubleshot using them at the D1 beamline station. He worked with CHESS Computer Specialist Phil Sorensen learning how to configure and test each motor, as well as write and debug macro language software that moved the multiple slits in useful ways. This was the first time this type of motor controller has run at CHESS.
Sophie McGough, from the University of California, Los Angeles, joined CHESS in the middle of summer 2003 and, having practical research skills and experience in computer programming, she was quickly and enthusiastic deployed to work with CHESS Staff Scientist Ken Finkelstein to develop programs for data reduction and modeling of complicated x-ray scattering geometries. This interest was well matched to the project needs. She first worked to interpret 2-dimensional x-ray scattering data recorded by large area 'CCD' detectors. A second project involved developing tools to model the influence of focusing optics on "coherent diffraction" patterns; i.e. when an x-ray beam made up of waves with well-defined relative phase illuminates a sample. An ERL x-ray source should provide beams of this quality, so it is important to anticipate such effects. The major challenge for Sophie was to learn to "think in reciprocal space" since x-ray diffraction patterns are naturally described in terms of the Fourier transform of real space structure in the sample. As soon as she understood this concept the programs began to flow! In both project she produced genuinely useful code that is presently being tested.
Soumendra Banerjee, a Cornell Undergraduate in Applied and Engineering Physics, has worked on two projects during this summer to help improve our capabilities in x-ray imaging. His first project involved writing software to automate direct imaging of x-rays using a CCD area detector produced by the MedOptics Corporation. His second project involved working with Rong Huang and Don Bilderback to collect x-ray fluorescence spectra using microscopic x-ray beams. In a typical measurement, a 10 micron x-ray beam is scanned across a specimen in an array of fine points. At each point the x-ray beam excites fluorescence from the specimen and the full spectrum is recorded.
Anton Kriksunov, a junior at Ithaca High School, worked to develop a web-interactive database for keeping track of scientific publications. As a growing organization, CHESS has growing needs to keep track of the scientific and technical report generated by both staff and users. The scientific and technical staff members produce large numbers of technical journal articles and presentations. CHESS users publish, on a whole, almost one paper for each day that CHESS is open for business. We need a system to keep track of all this output so that we can remember and recall information as well as report the laboratory output to the funding agencies. Anton has designed a system that can keep track of six kinds of publications: journal articles, books and chapters, patents, conference presentations, masters and Ph.D. theses, and internal staff reports and presentations. This system utilizes a web interface for entry, editing and searching for information. This will spread the onerous task of data entry among the staff and users and allow anyone to search the database.
Melissa Skala, is a junior physics major from Washington State University. As an REU (Research Experience for Undergraduates) she joined CHESS for a 10 week period this summer working towards using MCP optics (Micro Channel Plates) in fluorescence imaging. She obtained and characterized the commercially available MCP optics using the F3 and D1 beamlines, gaining much hands-on experimental experience. These optics are composed of thousands of microscopic pores, which could be used as a defining slit to directly image the fluorescence from a two dimensional sample onto a area detector.
Scott Forth, an undergraduate from Oberlin College (Oberlin, OH) spent a summer as an REU participant studying focusing of x-rays with refractive optics. His work consisted of designing, building, and testing several compound refractive x-ray lenses at CHESS. He achieved a gain of 2.5 with one such lens, while focusing a 12 keV beam to a width of approximately 10 microns. Such a beam could be used in various experiments due to its extremely small width and high intensity.
Jason Flannick, a Cornell undergraduate, worked during summer 2000 writing a Java application display program for the CHESS signal monitoring system. We have an existing system to monitor hundreds of critical parameters of the CHESS x-ray beamlines. This system has a limitation of only recording data once per minute. Jason wrote a new application that updates information once every 2-3 seconds.
Sami Rosenblatt, a Cornell Physics graduate student, worked with staff scientist Ken Finkelstein to design new focussing x-ray optical crystals based on silicon nanofabrication techniques. The project involves using the PT-770 Bosch Process Reactive Ion Etching machine to etch silicon wafers to a depth of 900 microns. We hope this fabrication technique will provide optics with much finer detailed grooves than can be made with standard mechanical machining techniques. Finer detail should result in more flexible optical elements with high pass-through efficiency and much smaller focal spot sizes; these two features will provide more usable photon flux into small specimens.
Anselm Levskaya is a Cornell freshman physics and math major. For the past year he has assisted in the design of high heat load components for the G-line expansion. Using the ANSYS finite element analysis code he has modeled the thermal and structural response of the G-line Crotch and B11W vacuum chamber to the intense power of the G-line 45 pole wiggler. His recent results were presented at the 2000 CHESS users meeting in June. Further he has analyzed the response of the A1 water-cooled mirror, in particular the critical effect of splitting the wiggler beam into two using the edge of the mirror. His calculations led the design of this cutting edge optic.
Dan Pringle was a first-year graduate student in physics. He worked with staff scientist Qun Shen in June-August 2000 in the development of a phase-sensitive reference-beam x-ray diffraction technique to obtain phases directly from a crystallography experiment. The principle of the technique is to combine the phase-sensitivity of three-beam diffraction with an oscillation camera that is the most popular data collection method in protein crystallography. During the period Dan finished the construction and the alignment of a new five-circle kappa diffractometer that is dedicated for the phase-sensitive measurements. He authored a computer routine to control the kappa goniometer so that an arbitrary Bragg reflection can be oriented onto the oscillation axis based on an initial oscillation image. Both the new hardware and the new software were tested successfully during a three-week experimental run in July at CHESS C-line on real protein crystals. During the run Dan was a full participant in equipment set-up and in experimental data collection. In the last few weeks of his stay at CHESS, Dan made further improvements to the kappa instrument and performed extensive data analysis that included peak indexing and integration from oscillation images and curve fitting to obtain phases from the measured reference-beam profiles. Dan's contributions to this work have been extremely valuable. As a result, two publications are being planned to document the advances that have been made at CHESS during this period.
Ivan Bazarov, a graduate student in Physics at Cornell, has been involved on the machine physics side of studying machine parameters for a possible new a dedicated synchrotron radiation facility called (at this point) an Energy Recovery Linac light source. Ivan has been calculating a trial machine lattice for both the superconducting linear accelerator portion as well as the attached one-turn storage ring. For doing these calculations, he has written a Pascal computer program to implement the calculation of the needed strengths of the various magnets and the beta functions.
D. J. Cooker (SUNY Albany, NY) was an REU student working with Don Bilderback to successfully produce one-bounce capillary optics for millibeam experiments. Several capillaries were pulled and characterized with x-rays.
Megan Toaspern (REU, Gettysburg College, PA) imaged the location of zinc in plant leaves with x-rays. The hyperaccumulator Thlaspi caerulescens from Prof. Leon Kochian's laboratory (USDA & Cornell Univ.) can absorb as much as 2% of its biomass in the form of zinc and still keep growing. The x-ray results show that ordinary non-accumulator plants have their "arteries" clogged with zinc and die with too much zinc. The hyperaccumulator, on the other hand, has the ability to move the zinc to the periphery of the plant leaf. This outstanding new research result was featured at the AIP Centennial in Atlanta in March, 1999. See an on-line Research Highlight on Megan's work.
Brock Aranson of the School of Applied and Engineering Physics completed a Masters of Engineering degree with Don Bilderback, awarded Spring of 1998. Brock's project was to design custom a x-ray sensitive photodiode with a hole in the center to pass an x-ray microbeam. With this geometry, we hope that more solid angle can be subtended during microprobe measurements. This is a project with the Cornell Nanofabrication Laboratory (Hercules Neves, Cornell). Not only did Brock design the photodiode, he fabricated prototypes in silicon. The prototypes didn’t function very well as diodes and are into the next round of redesign and fabrication.