2013 Argonne Conference


 

ANALYZING TIME DATA FOR THE EBEX EXPERIMENT

A large, complex experiment may involve the simultaneous operation of many instruments. Recording the time at which each data point was taken (a "timestamp") provides a way to relate it to the state of the overall experiment. However, the time data is just like any other data, so it develops anomalies that affect the final analysis. I looked at the time data for the EBEX experiment from the University of Minnesota, Twin Cities. EBEX is a balloon-borne polarimeter designed to observe the cosmic microwave background radiation in hopes of detecting E- and B-modes of polarization, which may lead to the discovery of gravitational waves in the early universe. I produced software that characterized anomalies in the time separation between sequential timestamps and counted their frequency. I found three types of anomalies, delta t: delta twas either too large or too small, or delta twas negative. Less than 1% of the total science data is affected by these anomalies.

Authors: Butler, Elizabeth C.; Hanany, Shaul
Northern Michigan University, Physics Department

 

EXPERIMENTAL IDENTIFICATION OF TRANSMISSION BAND SHIFTS FOR LIQUID-FILLED, HOLLOW CORE PHOTONIC CRYSTAL FIBERS DUE TO REFRACTIVE INDEX SCALING

Hollow core photonic crystal fibers have led to numerous developments in fiber technologies. Among these developments, these fibers have demonstrated possibility in optimizing numerous non-linear devices. Transmission bands produced by these fibers filled with liquid can be used to favor or prevent certain nonlinear mechanisms. Transmission bands produced by liquid filled fibers have been identified and used to validate the derived scaling laws that describe the shift in the bandgap location as the refractive index of the liquid is altered. Liquids of varying refractive index were made through different mixtures of dimethyl sulfoxide (DMSO) and water (H20). By filling the hollow core fibers with this liquid, transmission bands were identified through use of a supercontinuum white light source as well as an optical spectrum analyzer. The results of the transmission band location for each liquid mixture were analyzed and the data led to the conclusion that the shifts in the transmission bands follows the refractive index scaling laws more closely in the infrared region of the electromagnetic spectrum, but does not follow the refractive index scaling laws as the transmission band locations approach ultraviolet wavelength.

C. K. Hastings and A. Laursen were supported by NSF-REU grant No. PHY 1156620
Authors: Hastings, Cassandra, K; Laursen, Aaron; Delaye, Philippe
Northern Michigan University

 

TIME-OF-FLIGHT AND POSITION DISPERSION IN DIFFERENT CONFIGURATIONS OF PLASTIC SCINTILLATOR DETECTOR

This presentation is about time-of-flight and position dispersion in plastic scintillator detectors. Two different configurations of detector were tested: One configuration with a 120 degree bend in the detector and one configuration with a 90 degree bend. Cosmic rays were used as a source of ionizing radiation for these tests. One small scintillator detector was placed on top of a large one and a hardware-level coincidence was formed between the two in order to restrict the cosmic rays accepted to only those that hit the setup vertically. The small detector was then moved to different locations along the large detector in order to measure dispersion as a function of position along the large detector. The setup was allowed to run and collect data for a day or more for each test. For the time-of-flight spectrum, the difference in time between a cosmic ray hit in the mean-timed small detector and a hit in the mean-timed large detector was recorded and counted for each event. For the position spectrum, the difference in time between the left and right PMTs in the large detector was recorded and counted for each event. Both spectra were then fitted to a Gaussian peak and dispersion was calculated as the FWHM. The average time-of-flight dispersion was found to be 446.3 picoseconds for the 120 degree bend configuration and 333.1 picoseconds for the 90 degree bend configuration. The position dispersion was found to be 8.91 em for the 120 degree bend configuration and 6. 78cm for the 90 degree bend setup. The results of these tests provide an upper bound for time-of-flight and position dispersion (or resolution) in future experiments involving neutrons at

Jefferson National Laboratory
Authors: Wilbern, Daniel J.; Tireman, William L.
Northern Michigan University, Physics Department

 

MACROCYCLIC CR(III)MSALEN COMPLEXES FOR ASYMMETRIC CATALYTIC REACTIONS OF EPOXIDES

Epoxides are produced in millions of tons in the petrochemical industry. Via asymmetric catalytic reactions epoxides can be converted to chiral molecules, more valuable building blocks in the synthesis of drugs and other bioactive molecules. Three macrocyclic Cr(lll)-salen catalysts were synthesized via the ring-expanding olefin metathesis. The three macrocyclic catalysts differed in their carbon linkage lengths between the macrocyclic support and the Cr{lll)-salen complex. The catalysts' efficiency was assessed in asymmetric ring opening reaction of meso epoxides and kinetic resolution of terminal epoxides. In both reactions all three catalysts showed higher catalytic efficiency than the previous reported monomeric Cr(lll)-salen catalyst. A. S. Macias was supported by the Chemistry Department of Northern Michigan University.

Authors: Macias Sevde, Alejandro; Kinslow, Kurt; Liu,Yu
Northern Michigan University, Biology Department

 

MODTALK, A COMPILED SMALL TALK VARIANT

Modtalk is a Smalltalk variant, compiled to C. Modtalk retains the dynamic nature of Smalltalk and adds namespaces and modules. Compiling Smalltalk removes applications from their image-based environment and allows native executables for the platform. Modules and namespaces allow modularity in the programming environment.

Authors: Fridstrom, Joshua; Kilpela, Kurt; Sarkela, John
Northern Michigan University, Mathematics and Computer Science