Bulletin of the American Physical Society
Fall 2011 Meeting of the APS Prairie Section
Volume 56, Number 13
Thursday–Saturday, November 10–12, 2011; Cedar Falls, Iowa
Session B1: Poster Session I (6:00-7:30PM) |
Hide Abstracts |
Chair: Rui He, University of Northern Iowa Room: UNI Center for Enery and Environmental Education Rotunda |
|
B1.00001: Importance of cluster formation in quantum critical systems Tom Heitmann, John Gaddy, Jagat Lamsal, Wouter Montfrooij The presence of magnetic clusters has been verified in both antiferromagnetic and ferromagnetic quantum critical systems. We review some of the strongest evidence for heavily doped quantum critical systems Ce(Ru$_{0.24}$Fe$_{0.76})_{2}$Ge$_{2}$ and we discuss the implications for the response of the system when cluster formation is combined with finite size effects. In particular, we discuss the change of universality class that is observed close to the order-disorder transition and the conditions under which clustering effects will play a significant role also in the response of stoichiometric systems and their corresponding experimental signature. [Preview Abstract] |
|
B1.00002: Equations for the Origin of Stellar and Planetary Rotations Stewart Brekke Prior to stellar formation dense stellar cores of hydrogen gas with rotational momentum of $I\omega_{core}$ were orbited by partial rings of hydrogen gas which were in motion with angular momentum of mvr. As gravitational attraction of the rings occurred, the rings of gas decayed and tangentially collided and attached to the stellar cores transfering their angular momentum to the already rotating stellar cores creating final rotation. The equation for this final rotation is $ m_1v_1r_1 +m_2r_2v_2 + m_nv_nr_n + I\omega_{stellar core}= I_{\omega_{star}}$. Planetary formation began with rotating planetary cores of rotational momentum $I\omega_{planetary core}$. These cores were orbited by molten partial rings of compounds such as silicates, carbonates etc which decayed due to gravitational attraction. These rings had orbital angular momentum mvr. The decaying rings attached to the planetary cores tangentially tranfering their angular momentum and mass to the cores creating a final planetary rotation of $m_1v_1v_1 + m_2v_2r_2 +m_nv_nr_n + I\omega_{planetary core} = I\omega_{planet}$. [Preview Abstract] |
|
B1.00003: Matter and force particle modeling in a four-dimensional spin based space Steve Mulhall This model is a study of a discreet linear space of functions that are evaluated as representations of possible internal wave equations of matter and force particles. It is found that the model is a good first construction of a mathematical space that contains the wave equations of all known particles. The model starts with a basic spin function and builds particle wave equations in standard linear fashion in discreet steps through summations of functions. The model is four-dimensional and, in its current state, qualitative with some semiquantitative results. All quarks and leptons in the three generations of matter, along with gravitons, photons, gluons, and weak force bosons, but not the Higgs boson, are described, as well as many composite particles, including atomic nuclei. This poster describes the mathematical structure of the model and the results of calculations of the leptons and quarks of the first generation of matter, pion, and nucleons. A brief description of the second and third generation matter particles and hadrons is also presented. The structures of bosons are then derived by considering the possible interconversions of permutations of fermions. The resultant descriptions of the forces are highly consistent with observation. [Preview Abstract] |
|
B1.00004: IRAS 01202$+$6133 : A Possible Case of Protostellar Collapse Triggered by a Small HII Region Sung-Ju Kang, Charles Kerton The molecular gas surrounding an HII region is thought to be a place where star formation can be induced. This poster will present an analysis of submm spectroscopic observations of the submm/infrared source IRAS 01202$+$6133 located on the periphery of the HII region KR 120. HCO$^{+}$(J=3-2) spectra of this source show a classic asymmetric profile indicative of infall motions that would be expected to occur in the envelope surrounding a young protostellar object. Applying simple analytic models to these profiles we derive physical properties of the infall kinematics and the envelope structure. [Preview Abstract] |
|
B1.00005: ABSTRACT WITHDRAWN |
|
B1.00006: Examinaton of the February 2011 Forbush Decrease (Muon) by Project GRAND Molly Ball Project GRAND is a cosmic ray experiment located north of the University of Notre Dame. It consists of 64 huts of proportional wire chambers that make up a 100 m x 100 m detector array. These detectors identify muons produced when cosmic rays reach the Earth's upper atmosphere. The muon counting rates remain fairly constant, but this is not the case when there are solar flares and coronal mass ejections. An interesting occurrence called a Forbush Decrease was seen in February 2011 in data from the Oulu Neutron Monitor, a lower energy experiment than GRAND. This was caused by a cloud of charged particles and the magnetic fields moving toward Earth which deflect the path of charged cosmic rays that come from outside our solar system and bombard the Earth's upper atmosphere. GRAND's data was examined and a similar decrease at the same time as Oulu was found along with additional phenomenon not seen by Oulu, which usually sees more structure than GRAND due to its ability to detect lower energy particles more easily affected by solar activity. ~Several steps, such as looking at pressure correction and good hut corrections, have been taken to correct GRAND's data for non-physics effects. An upper air temperature correction remains to be done as well. [Preview Abstract] |
|
B1.00007: Effect of Ag Particles on the Fluorescence Properties of Eu Ions in Lead Borate Glasses Prakash Giri, Mahendra DC, Saisudha Mallur, P.K. Babu We have investigated the effect of Ag particles on the fluorescence of trivalent Eu ions in lead borate glasses. Lead borate glasses were prepared with varying Ag content (0 to 3 mol{\%}) and sizes of Ag particles were controlled by varying the duration of annealing near the glass transition temperature. Fluorescence spectra of all these samples were obtained at two different excitation wavelengths (395 nm and 464 nm). Glass samples with Ag particles show an increase in the intensities for the major peaks in the Eu fluorescence spectra, appearing near 589 nm and 613 nm. Detailed analysis show that the enhancement effects clearly depend on the duration of annealing and the concentration of Ag. Fluorescence intensity enhancement is readily observed at relatively shorter annealing time (5 h) for samples with higher Ag concentration whereas a much longer annealing time (25 h) is required to observe any significant enhancement in fluorescence intensity for lower concentration of Ag. For higher concentrations of Ag, a broad feature is seen around 450 nm due to the emission from Ag particles and the effect of Ag is more pronounced for the fluorescence peak at 589 nm. [Preview Abstract] |
|
B1.00008: Electrical Transport Anomalies in Nanometer Scale Manganese Films Erik Wolter, Tim Kidd, Andrew Stollenwerk, Aaron O'Shea Nanoscale structures have been studied for several decades, and they are used in applications such as solar cells, superconductors, and other devices in science and industry. Nanostructures have been defined to be materials with at least one dimension less than 100 nm. The properties are being studied and modified to make products faster, smaller, and more efficient. Manganese nanothilms were grown by thermal evaporation and resistance was measured \textit{in situ. }During the first stages of growth, the resistivity has an exponential dependence on thickness. This is consistent with Mn forming disconnected islands rather than a continuous film at low coverage. After the film reaches a critical thickness, the islands coalesce and the data can then be fitted with Fuchs' equation. The resistivity continues to decrease but the minimum resistivity of the film does not reach bulk resistivity because of the high density of defects in the film. AFM analysis verified that rougher films occur at faster growth rates and inhibit the continuity of thin films. Therefore a slow growth rate is important for growing smooth continuous films at nano sizes. [Preview Abstract] |
|
B1.00009: Elongated Hoop Structures in Quasi-1D Tantalum Di-Selenide Crystals Ben Beck Several novel topological crystal structures were discovered when performing scanning electron microscopy upon quasi-1D tantalum di-selenide crystals. The sample was comprised of mostly strand-like fibers with chemical compositions ranging from TaSe2 to TaSe3. These were randomly oriented as to create a macroscopic view akin to a matted nest. Upon further investigation of the sample, hoops and elongated hoop structures were discovered. The single hoops appeared to be comprised of a single strand connected at both ends. The elongated hoops most closely resembled spools of thread. The single hoops were most likely formed when a strand wrapped around a ball of liquid selenium during the formation of the crystals, as first discovered by Satoshsi Tanda of Hokkaido University. However, this theory does not adequately explain the formation of the elongated hoop structures, which have cylindrical interiors. These structures could be categorized in two different ways. Some were tightly wrapped much like a spool of thread while several resembled a slightly compressed spring. Currently, no clear theory has been developed for their creation, although we suspect inhomogeneities in the chemical stoichiometry to play a leading role. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700