PEP-II Status and Outlook (open access)

PEP-II Status and Outlook

PEP-II/BABAR are presently in their second physics run. With machine and detector performance and reliability at an all-time high, almost 51 fb{sup -1} have been integrated by BABAR up to mid-October 2001. PEP-II luminosity has reached 4.4 x 10{sup 33} cm{sup -2} s{sup -1} and our highest monthly delivered luminosity has been above 6 pb{sup -1}, exceeding the performance parameters given in the PEP-II CDR by almost 50%. The increase compared to the first run in 2000 has been achieved by a combination of beam-current increase and beam-size decrease. In this paper we will summarize the PEP-II performance and the present limitations as well as our plans to further increase machine performance.
Date: April 24, 2012
Creator: Wienands, H. U.; Biagini, M. E.; Decker, F. J.; Donald, M. H.; Ecklund, S.; Fisher, A. et al.
System: The UNT Digital Library
High Multiplicity Searches at the LHC Using Jet Masses (open access)

High Multiplicity Searches at the LHC Using Jet Masses

This article introduces a new class of searches for physics beyond the Standard Model that improves the sensitivity to signals with high jet multiplicity. The proposed searches gain access to high multiplicity signals by reclustering events into large-radius, or 'fat', jets and by requiring that each event has multiple massive jets. This technique is applied to supersymmetric scenarios in which gluinos are pair-produced and then subsequently decay to final states with either moderate quantities of missing energy or final states without missing energy. In each of these scenarios, the use of jet mass improves the estimated reach in gluino mass by 20% to 50% over current LHC searches.
Date: April 24, 2012
Creator: Hook, Anson; /SLAC /Stanford U., Appl. Phys. Dept.; Izaguirre, Eder; /SLAC /Stanford U., Phys. Dept.; Lisanti, Mariangela; U., /Princeton et al.
System: The UNT Digital Library
Compositional threshold for Nuclear Waste Glass Durability (open access)

Compositional threshold for Nuclear Waste Glass Durability

Within the composition space of glasses, a distinct threshold appears to exist that separates "good" glasses, i.e., those which are sufficiently durable, from "bad" glasses of a low durability. The objective of our research is to clarify the origin of this threshold by exploring the relationship between glass composition, glass structure and chemical durability around the threshold region.
Date: April 24, 2013
Creator: Kruger, Albert A.; Farooqi, Rahmatullah & Hrma, Pavel R.
System: The UNT Digital Library
Real space soft x-ray imaging at 10 nm spatial resolution (open access)

Real space soft x-ray imaging at 10 nm spatial resolution

Using Fresnel zone plates made with our robust nanofabrication processes, we have successfully achieved 10 nm spatial resolution with soft x-ray microscopy. The result, obtained with both a conventional full-field and scanning soft x-ray microscope, marks a significant step forward in extending the microscopy to truly nanoscale studies.
Date: April 24, 2011
Creator: Chao, Weilun; Fischer, Peter; Tyliszczak, T.; Rekawa, Senajith; Anderson, Erik & Naulleau, Patrick
System: The UNT Digital Library
Cosmic Ray Studies with the Fermi Gamma-ray Space Telescope Large Area Telescope (open access)

Cosmic Ray Studies with the Fermi Gamma-ray Space Telescope Large Area Telescope

None
Date: April 24, 2013
Creator: Thompson, D. J.; Baldini, L. & Uchiyama, Y.
System: The UNT Digital Library
redMaPPer II: X-ray and SZ Performance Benchmarks for the SDSS Catalog (open access)

redMaPPer II: X-ray and SZ Performance Benchmarks for the SDSS Catalog

None
Date: April 24, 2013
Creator: Rozo, Eduardo & Rykoff, Eli S.
System: The UNT Digital Library
redMaPPer I: Algorithm and SDSS DR8 Catalog (open access)

redMaPPer I: Algorithm and SDSS DR8 Catalog

None
Date: April 24, 2013
Creator: Rykoff, E. S.; Rozo, E.; Busha, M. T.; Cunha, C. E.; Finoguenov, A.; Evrard, A. et al.
System: The UNT Digital Library
Jet Substructure in ATLAS (open access)

Jet Substructure in ATLAS

None
Date: April 24, 2013
Creator: Miller, David W.
System: The UNT Digital Library
Interactions in 1-ethyl-3-methyl imidazolium tetracyanoborate ion pair: Spectroscopic and density functional study (open access)

Interactions in 1-ethyl-3-methyl imidazolium tetracyanoborate ion pair: Spectroscopic and density functional study

Density Functional Theory is used to investigate a weakly coordinating room-temperature ionic liquid, 1-ethyl-3-methyl imidazolium tetracyanoborate ([Emim]{sup +}[TCB]{sup -}). Four locally stable conformers of the ion pair were located. Atoms-in-molecules (AIM) and electron density analysis indicated the existence of several hydrogen bonds. Further investigation through the Natural Bond Orbital (NBO) and Natural Energy Decomposition Analysis (NEDA) calculations provided insight into the origin of interactions in the [Emim]{sup +}[TCB]{sup -} ion pair. Strength of molecular interactions in the ionic liquid was correlated with frequency shifts of the characteristic vibrations of the ion pair. Harmonic vibrations of the ion pair were also compared with the experimental Raman and Infrared spectra. Vibrational frequencies were assigned by visualizing displacements of atoms around their equilibrium positions and through Potential Energy Distribution (PED) analysis.
Date: April 24, 2013
Creator: Mao, James X.; Lee, Anita S.; Kitchin, John R.; Nulwala, Hunaid B; Luebke, David R. & Damodaran, Krishnan
System: The UNT Digital Library