Resource Type

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Daily movements of female white-tailed deer relative to parturition and breeding. (open access)

Daily movements of female white-tailed deer relative to parturition and breeding.

Abstract: To assess how white-tailed deer (Odocoileus virginianus) herd demographics influence reproductive behaviors, we examined 24-h diel movements of female whitetailed deer relative to parturition and breeding in a low-density population with a near even sex ratio at the Savannah River Site (SRS), South Carolina. We conducted a series of intensive, 24-h radio-tracking periods of 13 females during spring and fall 2002. We compared daily range (ha), rate of travel (m/h), and distance between extreme daily locations (m), among the periods of pre-parturition and post-parturition and pre-, peak-, and post-rut. From pre-parturition to post-parturition, we observed decreases in diel range size (–38.2%), distance between extreme diel locations (–17.0%), and diel rate of travel (–18.2%). Diel range size, distance between extreme diel locations, and diel rate of travel during the pre-rut and rut exceeded those observed during post-rut. We further identified substantial increases in mobility during 12 24-h diel periods for eight females during our fall monitoring. Our data suggest that female white-tailed deer reduce mobility post-fawning following exaggerated movements during pre-parturition. Furthermore, despite a near equal sex ratio, estrous does may be required to actively seek potential mates due to low population density.
Date: October 1, 2005
Creator: D'Angelo, Gino J.; Comer, Christopher E.; Kilgo, John C.; Drennan, Cory D.; Osborn, David A. & Miller, Karl V.
System: The UNT Digital Library
Expressions for the threshold current of multipass beam breakup in recirculating linacs from single cavity models (open access)

Expressions for the threshold current of multipass beam breakup in recirculating linacs from single cavity models

We investigate multipass beam breakup (BBU) in a recirculating linear accelerator in the framework of a single cavity model. We present expressions for the beam breakup threshold current for various situations derived from a perturbative solution of BBU equations. These formulae should serve as a guide to understand the BBU phenomenon for a particular system and also as a tool to estimate the BBU threshold current quickly. Many of the results presented are more general than previous considerations because they include the effects of coupling between the two transverse polarizations in each dipole higher order mode.
Date: October 1, 2005
Creator: Yunn, Byung C.
System: The UNT Digital Library
An Update on Reducing the Uncertainty in Solar Radiometric Measurements (open access)

An Update on Reducing the Uncertainty in Solar Radiometric Measurements

A presentation giving an update on reducing the uncertainty in solar radiometric measurements.
Date: October 1, 2005
Creator: Myers, D.; Reda, I.; Wilcox, S. & Lester, A.
System: The UNT Digital Library
A New Family of Transition Metal Nitrides (open access)

A New Family of Transition Metal Nitrides

The mechanical stability of platinum nitride has been studied using first-principles calculations. By calculating the single-crystal elastic constants, we show that platinum nitride can be stabilized in the fluorite structure, in which the nitrogen atoms occupy all the tetrahedral interstitial sites of the metal lattice. The stability is attributed to the pseudogap effect from analysis of the electronic structure.
Date: October 1, 2005
Creator: Yu, Rong & Zhang, Xiao-Feng
System: The UNT Digital Library
CDF's Higgs sensitivity status (open access)

CDF's Higgs sensitivity status

The combined sensitivity of CDF's current Standard Model Higgs boson searches is presented. The expected 95% CL limits on the production cross section times the relevant Higgs boson branching ratios are computed for the W{sup {+-}}H {yields} {ell}{sup {+-}}{nu}b{bar b}, ZH {yields} {nu}{bar {nu}}b{bar b}, gg {yields} H {yields} W{sup +}W{sup -} W{sup {+-}}H {yields} W{sup {+-}}W{sup +}W{sup -} channels as they stand as of the October 2005, using results which were prepared for Summer 2005 conferences and a newer result form the gg {yields} H {yields} W{sup +}W{sup -} channel. Correlated and uncorrelated systematic uncertainties are taken into account, and the luminosity requirements for 95% CL exclusion, 3{sigma} evidence, and 5{sigma} discovery are computed for median experimental outcomes. A list of improvements required to achieve the sensitivity to a SM Higgs boson as quantified in the Higgs Sensitivity Working Group's report is provided.
Date: October 1, 2005
Creator: Junk, Tom
System: The UNT Digital Library
H Diffusion through Partially Internally Oxidized Pd-alloy Membranes (U) (open access)

H Diffusion through Partially Internally Oxidized Pd-alloy Membranes (U)

In 1998 Kirchheim et al remarked that ''to their knowledge, experimental results on the diffusion of hydrogen through multi-layers have not yet been reported'' [1]. Their research dealt with diffusion through ultra-thin multi-layers of Nb/Pd which they followed electrochemically using a time-lag method. Their results were somewhat uncertain in that no final conclusion about any effect of the internal interfaces could be reached. Very recently Yamakawa et al [2] investigated Pd/Fe and Pd/Ni multilayers at 378-625 K and found no strong influence of the interfaces, however, there was grain boundary diffusion for the Pd/Ni layers and retardation, possibly due to dislocation trapping. Takano et al [3] studied H diffusion through thin layers of Pd, Ni, or Cu deposited electrochemically on Fe and concluded that complications are introduced by thin films perhaps H trapping at vacancies as the thickness of the layer decreases to very small values. Holleck [4] measured H diffusion through mm thick Pd{sub 0.75}Ag{sub 0.25}/Ta/Pd{sub 0.75}Ag{sub 0.25} layers in the gas phase from 540-873 K and determined D{sub H,Ta} from the overall diffusion constant and the known D{sub H,alloy}; he concluded that the interface did not play a significant role at these temperatures. As in Holleck's, the present …
Date: October 1, 2005
Creator: Wang, D.; Flanagan, Ted B. & Shanahan, K. L.
System: The UNT Digital Library
Standard model and supersymmetric Higgs searches at CDF (open access)

Standard model and supersymmetric Higgs searches at CDF

We present the results on the searches for the SM and the MSSM Higgs boson production in proton-antiproton collisions at {radical}s = 1.96 GeV with the CDF detector. The Higgs bosons are searched for in various production and decay channels, with data samples corresponding to 400 pb{sup -1}. Using these measurements, we set an upper limit on the production cross section times branching fraction for the Standard Model Higgs as a function of the Higgs mass, and we obtain exclusion regions in the tan{beta} vs mass for the neutral MSSM Higgs, and branching fraction vs mass for the charged Higgs.
Date: October 1, 2005
Creator: Kilminster, Ben
System: The UNT Digital Library
Time, Energy, and Spatially Resolved TEM Investigations of Defectsin InGaN (open access)

Time, Energy, and Spatially Resolved TEM Investigations of Defectsin InGaN

A novel sample preparation technique is reported to fabricate electron transparent samples from devices utilizing a FIB process with a successive wet etching step. The high quality of the obtained samples allows for band gap--and chemical composition measurements of In{sub x}Ga{sub 1-x}N quantum wells where electron beam induced damage can be controlled and shown to be negligible. The results reveal indium enrichment in nanoclusters and defects that cause fluctuations of the band gap energy and can be measured by low loss Electron Energy Spectroscopy with nm resolution. Comparing our time, energy, and spatially resolved measurements of band gap energies, chemical composition, and their related fluctuations with literature data, we find quantitative agreement if the band gap energy of InN is 1.5-2 eV.
Date: October 1, 2005
Creator: Jinschek, J. R. & Kisielowski, C.
System: The UNT Digital Library
Ferroelectric Plasma Source for Heavy Ion Beam ChargeNeutralization (open access)

Ferroelectric Plasma Source for Heavy Ion Beam ChargeNeutralization

Plasmas are employed as a source of unbound electrons for charge neutralizing heavy ion beams to allow them to focus to a small spot size. Calculations suggest that plasma at a density of 1-100 times the ion beam density and at a length {approx} 0.1-1 m would be suitable. To produce one-meter plasma, large-volume plasma sources based upon ferroelectric ceramics are being developed. These sources have the advantage of being able to increase the length of the plasma and operate at low neutral pressures. The source utilizes the ferroelectric ceramic BaTiO{sub 3} to form metal plasma. The drift tube inner surface of the Neutralized Drift Compression Experiment (NDCX) will be covered with ceramic, and high voltage ({approx} 1-5 kV) applied between the drift tube and the front surface of the ceramic by placing a wire grid on the front surface. A prototype ferroelectric source 20 cm long has produced plasma densities of 5 x 10{sup 11} cm{sup -3}. The source was integrated into the previous Neutralized Transport Experiment (NTX), and successfully charge neutralized the K{sup +} ion beam. Presently, the one-meter source is being fabricated. The source is being characterized and will be integrated into NDCX for charge neutralization experiments.
Date: October 1, 2005
Creator: Efthimion, Philip C.; Gilson, Erik P.; Grisham, Larry; Davidson,Ronald C.; Yu, Simon; Waldron, William et al.
System: The UNT Digital Library
Measurement of the K- pi+ S-wave system in D+ ---> K- pi+ pi+ decays from Fermilab E791 (open access)

Measurement of the K- pi+ S-wave system in D+ ---> K- pi+ pi+ decays from Fermilab E791

A new approach to the analysis of three body decays is presented. Measurements of the S-wave K{pi} amplitude are made in independent ranges of invariant mass from threshold up to the upper kinematic limit in D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +} decays. These are compared with results obtained from a fit where the S-wave is assumed to have {kappa} and K{sub 0}{sup +}(1430) resonances. Results are also compared with measurements of K{sup -} {pi}{sup +} elastic scattering. Contributions from I = 1/2 and I = 3/2 are not resolved in this study. If I = 1/2 dominates, however, the Watson theorem prediction, that the phase behavior below K{eta}' threshold should match that in elastic scattering, is not well supported by these data. Production of K{sup -} {pi}{sup +} from these D decays is also studied.
Date: October 1, 2005
Creator: Meadows, B. & U., /Cincinnati
System: The UNT Digital Library
Theta(13) (open access)

Theta(13)

None
Date: October 1, 2005
Creator: Parke, Stephen J.
System: The UNT Digital Library
Conjecture on the physical implications of the scale anomaly (open access)

Conjecture on the physical implications of the scale anomaly

Murray Gell-Mann, after co-inventing QCD, recognized the interplay of the scale anomaly, the renormalization group, and the origin of the strong scale, {Lambda}{sub QCD}. I tell a story, then elaborate this concept, and for the sake of discussion, propose a conjecture that the physical world is scale invariant in the classical, {h_bar}, limit. This principle has implications for the dimensionality of space-time, the cosmological constant, the weak scale, and Planck scale.
Date: October 1, 2005
Creator: Hill, Christopher T.
System: The UNT Digital Library
Effect of high solenoidal magnetic fields on breakdown voltages of high vacuum 805 MHz cavities (open access)

Effect of high solenoidal magnetic fields on breakdown voltages of high vacuum 805 MHz cavities

There is an on going international collaboration studying the feasibility and cost of building a muon collider or neutrino factory [1,2]. An important aspect of this study is the full understanding of ionization cooling of muons by many orders of magnitude for the collider case. An important muon ionization cooling experiment, MICE [3], has been proposed to demonstrate and validate the technology that could be used for cooling. Ionization cooling is accomplished by passing a high-emittance muon beam alternately through regions of low Z material, such as liquid hydrogen, and very high accelerating RF Cavities within a multi-Tesla solenoidal field. To determine the effect of very large solenoidal magnetic fields on the generation of dark current, x-rays and on the breakdown voltage gradients of vacuum RF cavities, a test facility has been established at Fermilab in Lab G. This facility consists of a 12 MW 805 MHz RF station and a large warm bore 5 T solenoidal superconducting magnet containing a pill box type cavity with thin removable window apertures. This system allows dark current and breakdown studies of different window configurations and materials. The results of this study will be presented. The study has shown that the peak achievable …
Date: October 1, 2005
Creator: Moretti, A.; Bross, A.; Geer, S.; Qian, Z.; Norem, J.; Li, D. et al.
System: The UNT Digital Library
Pixel multi chip module development at Fermilab (open access)

Pixel multi chip module development at Fermilab

At Fermilab, there is an ongoing pixel detector R&D effort for High Energy Physics with the objective of developing high performance vertex detectors suitable for the next generation of HEP experiments. The pixel module presented here is a direct result of work undertaken for the canceled BTeV experiment. It is a very mature piece of hardware, having many characteristics of high performance, low mass and radiation hardness driven by the requirements of the BTeV experiment. The detector presented in this paper consists of three basic devices; the readout integrated circuit (IC) FPIX2A [2][5], the pixel sensor (TESLA p-spray) [6] and the high density interconnect (HDI) flex circuit [1][3] that is capable of supporting eight readout ICs. The characterization of the pixel multichip module prototype as well as the baseline design of the eight chip pixel module and its capabilities are presented. These prototypes were characterized for threshold and noise dispersion. The bump-bonds of the pixel module were examined using an X-ray inspection system. Furthermore, the connectivity of the bump-bonds was tested using a radioactive source ({sup 90}Sr), while the absolute calibration of the modules was achieved using an X-ray source. This paper provides a view of the integration of the …
Date: October 1, 2005
Creator: Turqueti, M. A.; Cardoso, G.; Andresen, J.; Appel, J. A.; Christian, D. C.; Kwan, S. W. et al.
System: The UNT Digital Library
Inferred limits on lepton flavor violating decays of the Ks (open access)

Inferred limits on lepton flavor violating decays of the Ks

Strong model independent upper bounds on Br(K{sub s} {yields} {pi}{sup 0} e{mu}) may be inferred from recent experimental limits on Br(K{sub L} {yields} {pi}{sup 0} e{mu}) and Br(K{sup +} {yields} {pi}{sup +}e{sup +}{mu}{sup -}). From this result, upper bounds for Br(K{sub s} {yields} e{mu}) may be obtained for a broad class of models. Models outside of this class seem unlikely.
Date: October 1, 2005
Creator: Bellantoni, L.
System: The UNT Digital Library
Squark and gluino production with jets (open access)

Squark and gluino production with jets

We present cross section predictions for squark and gluino production at the LHC, in association with up to two additional hard jets. These cross sections can be very large in comparison to the inclusive Born rates. Because hadron collider experiments utilize hard jets in the reconstruction of cascade decays or as a way to separate squark and gluino production, the understanding of these processes is crucial. We show to what degree hard jet radiation can be described by shower algorithms and point out how tuning these showers, for example to top quark pair production, could help reduce theoretical uncertainties for new physics searches at the LHC.
Date: October 1, 2005
Creator: Plehn, T.; Rainwater, D. & Skands, P.
System: The UNT Digital Library
A Search for the Most Massive Galaxies: Double Trouble? (open access)

A Search for the Most Massive Galaxies: Double Trouble?

We describe the results of a search for galaxies with large ({approx}> 350 kms{sup -1}) velocity dispersions. The largest systems we have found appear to be the extremes of the early-type galaxy population: compared to other galaxies with similar luminosities, they have the largest velocity dispersions and the smallest sizes. However, they are not distant outliers from the Fundamental Plane and mass-to-light scaling relations defined by the bulk of the early-type galaxy population. They may host the most massive black holes in the Universe, and their abundance and properties can be used to constrain galaxy formation models. Clear outliers from the scaling relations tend to be objects in superposition (angular separations smaller than 1 arcsec), evidence for which comes sometimes from the spectra, sometimes from the images, and sometimes from both. The statistical properties of the superposed pairs, e.g., the distribution of pair separations and velocity dispersions, can be used to provide useful information about the expected distribution of image multiplicities, separations and flux ratios due to gravitational lensing by multiple lenses, and may also constrain models of their interaction rates.
Date: October 1, 2005
Creator: Bernardi, Mariangela; Sheth, R. K.; Nichol, R. C.; Miller, C. J.; Schlegel, D.; Frieman, J. et al.
System: The UNT Digital Library
Prospects for detecting dark matter with neutrino telescopes in light of recent results from direct detection experiments (open access)

Prospects for detecting dark matter with neutrino telescopes in light of recent results from direct detection experiments

Direct detection dark matter experiments, lead by the CDMS collaboration, have placed increasingly stronger constraints on the cross sections for elastic scattering of WIMPs on nucleons. These results impact the prospects for the indirect detection of dark matter using neutrino telescopes. With this in mind, we revisit the prospects for detecting neutrinos produced by the annihilation of WIMPs in the Sun. We find that the latest bounds do not seriously limit the models most accessible to next generation kilometer-scale neutrino telescopes such as IceCube. This is largely due to the fact that models with significant spin-dependent couplings to protons are the least constrained and, at the same time, the most promising because of the efficient capture of WIMPs in the Sun. We identify models where dark matter particles are beyond the reach of any planned direct detection experiments while within reach of neutrino telescopes. In summary, we find that, even when contemplating recent direct detection results, neutrino telescopes still have the opportunity to play an important as well as complementary role in the search for particle dark matter.
Date: October 1, 2005
Creator: Halzen, Francis & Hooper, Dan
System: The UNT Digital Library
REGIONAL HYDROLOGY OF THE NOPAL 1 SITE, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO (open access)

REGIONAL HYDROLOGY OF THE NOPAL 1 SITE, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

The objectives of this report are: (1) Determine the main source of the groundwater (GW) found within the DOE wells (PB-1, PB-2, and PB-3); and (2) Determine whether the Nopal I GW has any relationship to the connectivity between the regional Encinillas Aquifer to the west and the El Cuervo Aquifer to the east.
Date: October 1, 2005
Creator: Rodriguez-Pineda, J.A.; Goodell, P.; Dobson, P.; Walton, J.; Olver, R.; Garza, R. de la et al.
System: The UNT Digital Library
Probing exotic physics with cosmic neutrinos (open access)

Probing exotic physics with cosmic neutrinos

Traditionally, collider experiments have been the primary tool used in searching for particle physics beyond the Standard Model. In this talk, I will discuss alternative approaches for exploring exotic physics scenarios using high energy and ultra-high energy cosmic neutrinos. Such neutrinos can be used to study interactions at energies higher, and over baselines longer, than those accessible to colliders. In this way, neutrino astronomy can provide a window into fundamental physics which is highly complementary to collider techniques. I will discuss the role of neutrino astronomy in fundamental physics, considering the use of such techniques in studying several specific scenarios including low scale gravity models, Standard Model electroweak instanton induced interactions, decaying neutrinos and quantum decoherence.
Date: October 1, 2005
Creator: Hooper, Dan
System: The UNT Digital Library
B meson mixing at CDF II (open access)

B meson mixing at CDF II

None
Date: October 1, 2005
Creator: Rescigno, Marco & /INFN, Rome
System: The UNT Digital Library
Twenty years of diffraction at the Tevatron (open access)

Twenty years of diffraction at the Tevatron

Results on diffractive particle interactions from the Fermilab Tevatron {bar p}p collider are placed in perspective through a QCD inspired phenomenological approach, which exploits scaling and factorization properties observed in data. The results discussed are those obtained by the CDF Collaboration from a comprehensive set of single, double, and multigap soft and hard diffraction processes studied during the twenty year period since 1985, when the CDF diffractive program was proposed and the first Blois Workshop was held.
Date: October 1, 2005
Creator: Goulianos, K.
System: The UNT Digital Library
Tracking at CDF: algorithms and experience from Run I and Run II (open access)

Tracking at CDF: algorithms and experience from Run I and Run II

The authors describe the tracking algorithms used during Run I and Run II by CDF at the Fermilab Tevatron Collider, covering the time from about 1992 through the present, and discuss the performance of the algorithms at high luminosity. By tracing the evolution of the detectors and algorithms, they reveal some of the successful strategies used by CDF to address the problems of tracking at high luminosities.
Date: October 1, 2005
Creator: Snider, F.D.
System: The UNT Digital Library
Constraining inverse curvature gravity with supernovae (open access)

Constraining inverse curvature gravity with supernovae

We show that the current accelerated expansion of the Universe can be explained without resorting to dark energy. Models of generalized modified gravity, with inverse powers of the curvature can have late time accelerating attractors without conflicting with solar system experiments. We have solved the Friedman equations for the full dynamical range of the evolution of the Universe. This allows us to perform a detailed analysis of Supernovae data in the context of such models that results in an excellent fit. Hence, inverse curvature gravity models represent an example of phenomenologically viable models in which the current acceleration of the Universe is driven by curvature instead of dark energy. If we further include constraints on the current expansion rate of the Universe from the Hubble Space Telescope and on the age of the Universe from globular clusters, we obtain that the matter content of the Universe is 0.07 {le} {omega}{sub m} {le} 0.21 (95% Confidence). Hence the inverse curvature gravity models considered can not explain the dynamics of the Universe just with a baryonic matter component.
Date: October 1, 2005
Creator: Mena, Olga; Santiago, Jose & Weller, Jochen
System: The UNT Digital Library