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Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam (open access)

Alignment of the Pixel and SCT Modules for the 2004 ATLAS Combined Test Beam

A small set of final prototypes of the ATLAS Inner Detector silicon tracking system(Pixel Detector and SemiConductor Tracker), were used to take data during the 2004 Combined Test Beam. Data were collected from runs with beams of different flavour (electrons, pions, muons and photons) with a momentum range of 2 to 180 GeV/c. Four independent methods were used to align the silicon modules. The corrections obtained were validated using the known momenta of the beam particles and were shown to yield consistent results among the different alignment approaches. From the residual distributions, it is concluded that the precision attained in the alignmentof the silicon modules is of the order of 5 mm in their most precise coordinate.
Date: June 2, 2008
Creator: Ahmad, A.; Andreazza, A.; Atkinson, T.; Baines, J.; Barr, A. J.; Beccherle, R. et al.
Object Type: Article
System: The UNT Digital Library
Deprotection blue in extreme ultraviolet photoresists: influence of base loading and post-exposure bake temperture (open access)

Deprotection blue in extreme ultraviolet photoresists: influence of base loading and post-exposure bake temperture

The deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP5496 extreme ultraviolet photoresists has been determined as their base weight percent is varied. They have also determined the deprotection blur of TOK EUVR P1123 photoresist as the post-exposure bake temperature is varied from 80 C to 120 C. In Rohm and Haas XP 5435 and XP5271 resists 7x and 3x (respective) increases in base weight percent reduce the size of successfully patterned 1:1 line-space features by 16 nm and 8 nm with corresponding reductions in deprotection blur of 7 nm and 4 nm. In XP 5496 a 7x increase in base weight percent reduces the size of successfully patterned 1:1 line-space features from 48 nm to 38 nm without changing deprotection blur. In TOK EUVR P1123 resist, a reduction in post-exposure bake temperature from 100 C to 80 C reduces deprotection blur from 21 nm to 10 nm and reduces patterned LER from 4.8 nm to 4.1 nm.
Date: June 2, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Object Type: Article
System: The UNT Digital Library
Don't always blame the photons: Relationships between deprotection blur, LER, and shot noise in EUV photoresists (open access)

Don't always blame the photons: Relationships between deprotection blur, LER, and shot noise in EUV photoresists

A corner rounding metric has been used to determine the deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP 5496 extreme ultraviolet (EUV) photoresists as base weight percent is varied; an experimental open platform photoresist (EH27) as base weight percent is varied; and TOK EUVR P1123 and FUJI 1195 photoresists as post-exposure bake (PEB) temperature is varied. In the XP 5435, XP 5271, XP 5496, and EH27 resist platforms, a 6 times increase in base weight percent reduces the size of successfully patterned 1:1 lines by over 10 nm and lowers intrinsic line-edge roughness (LER) by over 2.5 nm without changing deprotection blur. In TOK EUVR P1123 photoresist, lowering the PEB temperature from 100 C to 80 C reduces measured deprotection blur (using the corner metric) from 30 nm to 20 nm and reduces the LER of 50 nm 1:1 lines from 4.8 nm to 4.3 nm. These data are used to drive a lengthy discussion about the relationships between deprotection blur, LER, and shot noise in EUV photoresists. We provide two separate conclusions: (1) shot noise is probably not the dominant mechanism causing the 3-4 nm EUV LER floor that has been observed over the past …
Date: June 2, 2008
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Object Type: Article
System: The UNT Digital Library
Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons (open access)

Measurements of B to {pi, eta, eta'} l nu Branching Fractions andDetermination of |Vub| with Semileptonically Tagged B Mesons

The authors report measurements of branching fractions for the decays B {yields} P{ell}{nu}{sub {ell}}, where P are the pseudoscalar charmless mesons {pi}{sup -}, {pi}{sup 0}, {eta} and {eta}{prime}, based on 348 fb{sup -1} of data collected with the BABAR detector, using B{sup 0} and B{sup +} mesons found in the recoil of a second B meson decaying as B {yields} D{sup (*)}{ell}{nu}{sub {ell}}. Assuming isospin symmetry, they combine pionic branching fractions to obtain {Beta}(B{sup 0} {yields} {pi}{sup -} {ell}{sup +} {nu}{sub {ell}}) = (1.54 {+-} 0.17{sub (stat)} {+-} 0.09{sub (syst)}) x 10{sup -4}; they find 3.2{sigma} evidence of the decay B{sup +} {yields} {eta}{ell}{sup +}{nu}{sub {ell}} and measure its branching fraction to be (0.64 {+-} 0.20{sub (stat)} {+-} 0.3{sub (syst)}) x 10{sup -4}, and determine {Beta}(B{sup +} {yields} {eta}{prime}{ell}{sup +}{nu}{sub {ell}}) < 0.47 x 10{sup -4} to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a recent form factor calculation, they obtain the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}| = (4.0 {+-} 0.5{sub (stat)} {+-} 0.2{sub (syst){sub -0.5}{sup +0.7}(theory)}) x 10{sup -3}.
Date: June 2, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions (open access)

Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions

This document contains the final report for DOE grant DE-FG02-03ER41239: Modeling and Analysis of Ultra-Relativistic Heavy-Ion Collisions
Date: June 2, 2008
Creator: Bass, Steffen A.
Object Type: Text
System: The UNT Digital Library

Synthesis and Chemistry of Polyfunctionalized Cyclohexasilanes

None
Date: June 2, 2008
Creator: Boudjouk, Philip; Kim, Beon-Kyu; Choi, Seok-Bong; Dai, Xuliang; Pokhodnya, Kostantin; Nelson, Kendric et al.
Object Type: Presentation
System: The UNT Digital Library
Polar Bears: Listing Under the Endangered Species Act (open access)

Polar Bears: Listing Under the Endangered Species Act

This report discusses the protection of polar bears under the Endangered Species Act and how they are affected by climate change, contaminants, and subsistence and sport hunting.
Date: June 2, 2008
Creator: Buck, Eugene H. & Corn, M. L.
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 109, No. 313, Ed. 1 Monday, June 2, 2008 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 313, Ed. 1 Monday, June 2, 2008

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: June 2, 2008
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Probabilistic consequence model of accidenal or intentional chemical releases. (open access)

Probabilistic consequence model of accidenal or intentional chemical releases.

In this work, general methodologies for evaluating the impacts of large-scale toxic chemical releases are proposed. The potential numbers of injuries and fatalities, the numbers of hospital beds, and the geographical areas rendered unusable during and some time after the occurrence and passage of a toxic plume are estimated on a probabilistic basis. To arrive at these estimates, historical accidental release data, maximum stored volumes, and meteorological data were used as inputs into the SLAB accidental chemical release model. Toxic gas footprints from the model were overlaid onto detailed population and hospital distribution data for a given region to estimate potential impacts. Output results are in the form of a generic statistical distribution of injuries and fatalities associated with specific toxic chemicals and regions of the United States. In addition, indoor hazards were estimated, so the model can provide contingency plans for either shelter-in-place or evacuation when an accident occurs. The stochastic distributions of injuries and fatalities are being used in a U.S. Department of Homeland Security-sponsored decision support system as source terms for a Monte Carlo simulation that evaluates potential measures for mitigating terrorist threats. This information can also be used to support the formulation of evacuation plans and …
Date: June 2, 2008
Creator: Chang, Y.-S.; Samsa, M. E.; Folga, S. M. & Hartmann, H. M.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 88, No. 153, Ed. 1 Monday, June 2, 2008 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 88, No. 153, Ed. 1 Monday, June 2, 2008

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: June 2, 2008
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Connecting Galaxies, Halos, and Star Formation Rates Across Cosmic Time (open access)

Connecting Galaxies, Halos, and Star Formation Rates Across Cosmic Time

A simple, observationally-motivated model is presented for understanding how halo masses, galaxy stellar masses, and star formation rates are related, and how these relations evolve with time. The relation between halo mass and galaxy stellar mass is determined by matching the observed spatial abundance of galaxies to the expected spatial abundance of halos at multiple epochs--i.e. more massive galaxies are assigned to more massive halos at each epoch. This 'abundance matching' technique has been shown previously to reproduce the observed luminosity- and scale-dependence of galaxy clustering over a range of epochs. Halos at different epochs are connected by halo mass accretion histories estimated from N-body simulations. The halo-galaxy connection at fixed epochs in conjunction with the connection between halos across time provides a connection between observed galaxies across time. With approximations for the impact of merging and accretion on the growth of galaxies, one can then directly infer the star formation histories of galaxies as a function of stellar and halo mass. This model is tuned to match both the observed evolution of the stellar mass function and the normalization of the observed star formation rate--stellar mass relation to z {approx} 1. The data demands, for example, that the star …
Date: June 2, 2008
Creator: Conroy, Charlie & Wechsler, Risa H.
Object Type: Article
System: The UNT Digital Library

Doctoral Recital: 2008-06-02 - Elena Dorozhkina, piano

Recital presented at the UNT College of Music Concert Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: June 2, 2008
Creator: Dorozhkina, Elena
Object Type: Sound
System: The UNT Digital Library
Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses (open access)

Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses

This report focuses on options for protecting structures and for protecting wildlands and natural resources from wildfires. It begins with a brief overview of the nature of wildfires, followed by a discussion of protecting structures. Then, it discusses wildfire damages to wildlands and natural resources, fuel treatment options and their benefits and limitations, and public involvement in federal decisions.
Date: June 2, 2008
Creator: Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses (open access)

Wildfire Damages to Homes and Resources: Understanding Causes and Reducing Losses

This report focuses on options for protecting structures, wildlands, and natural resources from wildfires. It begins with a brief overview of the nature of wildfires, followed by a discussion of protecting structures. Then it discusses wildfire damages to wildlands and natural resources; fuel treatment options and their benefits and limitations; and public involvement in federal decisions.
Date: June 2, 2008
Creator: Gorte, Ross W.
Object Type: Report
System: The UNT Digital Library
The Longhorn Express (Harper, Tex.), Vol. 10, No. 5, Ed. 1 Monday, June 2, 2008 (open access)

The Longhorn Express (Harper, Tex.), Vol. 10, No. 5, Ed. 1 Monday, June 2, 2008

Student newspaper of Harper Independent School District in Harper, Texas that includes school news and information along with advertising.
Date: June 2, 2008
Creator: Harper Independent School District Journalism Class
Object Type: Newspaper
System: The Portal to Texas History
Aqueous Ln(III) Luminescence Agents Derived from a Tasty Precursor (open access)

Aqueous Ln(III) Luminescence Agents Derived from a Tasty Precursor

The synthesis, aqueous stability and photophysical properties are reported for a novel tetradentate ligand derived from maltol, a commonly used flavor enhancer. In aqueous solution, this chelate forms stable complexes with Ln(III) cations, and sensitized emission was observed from Eu(III), Yb(III), and Nd(III). A comparison with recently reported and structurally analogous ligands reveals a slightly higher basicity but lower complex stability with Eu(III) [pEu = 14.7 (1)]. A very poor metal centered quantum yield with Eu(III) was observed ({Phi}{sub tot} = 0.04%), which can be rationalized by the similar energy of the ligand triplet state and the Eu(III) {sup 5}D{sub 0} emissive level. Instead, sensitized emission from the Yb(III) and Nd(III) cations was observed, which emit in the Near Infra-Red (NIR).
Date: June 2, 2008
Creator: Jocher, C. J.; Moore, E. G.; Pierce, J. D. & Raymond, K. N.
Object Type: Article
System: The UNT Digital Library

[Bookshelves in Research Park Library]

Photograph of an interior view of Research Park Library, at the University of North Texas. In the foreground, there are two bookshelves. Many of the shelves are bare. Behind the bookshelves, there is a table and set of chairs. A glass doorway is visible in the background.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Close-Up View of Bookshelf Sign]

Photograph of a close-up view of a bookshelf sign in Research Park Library, at the University of North Texas. The sign says "Microlithography World - Plastics Technology." Research Park is now known as Discovery Park.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Close-Up View of Bookshelves]

Photograph of a close-up view of labels on compact bookshelves at Research Park Library, at the University of North Texas. One legible label says "Row 58 [-] Z732.T4R - Z5076.U5v37" and "Spacesaver High-Density Systems - Southwest Solutions Group[,] 800/803-1083."
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Close-Up View of Bookshelves]

Photograph of a close-up view of compact bookshelves at Research Park Library, at the University of North Texas. Crank mechanisms are on the side of each shelf. Books are visible on the first shelf.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Compact Bookshelves at Research Park Library]

Photograph of compact bookshelves at Research Park Library, at the University of North Texas. The shelves are lined up with one open shelf visible. Crank mechanisms are on the side of each shelf. On the left side, there are two book carts and a step ladder. Research Park is now known as Discovery Park. A trash can stands on the right side of the aisle by the bookshelves.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Compact Bookshelves at Research Park Library]

Photograph of compact bookshelves at Research Park Library, at the University of North Texas. The shelves are lined up with one open shelf visible. Crank mechanisms are on the side of each shelf. On the left side, there are two book carts and a step ladder. A trash can stands on the right side of the aisle by the bookshelves. Research Park is now known as Discovery Park.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Compact Bookshelves at Research Park Library]

Photograph of compact bookshelves at Research Park Library, at the University of North Texas. The shelves are lined up with one open shelf visible. Crank mechanisms are on the side of each shelf. On the right side, there are two book carts. In the background, a glass doorway is visible. Research Park is now known as Discovery Park.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History

[Compact Bookshelves at Research Park Library]

Photograph of compact bookshelves at Research Park Library, at the University of North Texas. Books are visible on the first shelf. The shelves are lined up next to each other, with one visible opening. Crank mechanisms are on the side of each shelf. On the right, there are two book carts and a step ladder. Research Park is now known as Discovery Park.
Date: June 2, 2008
Creator: Jones, Jerrell
Object Type: Photograph
System: The Portal to Texas History