A New Outlook for Cosmology. PAUL HIGGINS (Contra Costa College San Pablo, CA 94806) MICHAEL BARNETT (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

The Universe Adventure is a website designed to teach high school students and the general public about the fundamentals of cosmology, the study of the dynamics and evolution of the universe. The participant is taken through the history of cosmological models, such as the Geocentric (Greek) and Heliocentric (European Renaissance) models. The Big Bang (present day) model is then discussed, including supporting evidence. The rest of the website is devoted to explaining how the universe has changed from its initial hot, dense state into the current state we now observe and map with our telescopes. What distinguishes The Universe Adventure, is the way in which its physics concepts are presented. There is a liberal use of analogies, metaphors, animation, diagrams, illustrations, photographs, and humor in order to ensure interest and comprehension for high school students, teachers and the general public. The fundamental idea is to break away from academic methods of teaching physics. This website could act as a supplement to course work, or merely as a resource for curious minds. This summer was spent revising existing content, and expanding on that content by creating more in depth explanations, graphics and animation.

And There Was Light - Analyzing the Cosmic Microwave Background Using Interactive Data Language. DANIELLE SPELLER (North Carolina State University Raleigh, NC 27695) GEORGE F. SMOOT (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

The discovery of the Cosmic Microwave Background (CMB) is a major development in the field of cosmology that has been instrumental in raising cosmology from a qualitative to a quantitative science, allowing more accurate, precise measurements for fundamental constants and providing a way to discriminate between various theories of cosmic origin and evolution. An important feature of the CMB is the presence of tiny temperature anisotropies in what is otherwise an isotropic and homogeneous sea of radiation. Current theories and models predict a Gaussian distribution for these anisotropies, and much research has been devoted to the statistical analysis of the CMB. We tested the Gaussianity of a small portion of the first year WMAP map (10 degree radius, at [0,90] galactic coordinates) by comparing its statistical moments with those of 1000 Monte Carlo simulated CMB samples. We also formed a rough comparison of the WMAP signal data to a Gaussian of the same mean and standard deviation. It was found that the mean, skewness, and kurtosis of the 94 GHz frequency map fell within one standard deviation of the mean values for the simulations and is compatible within 78% probablility. Qualitatively, the skewness and kurtosis of the WMAP data in comparison with the simulated analysis suggests Gaussianity. This conclusion of Gaussianity is in agreement with several previous studies of the statistical distribution of the background anisotropies.

Prototyping a "Pure" COS- Superconducting Dipole Magnet. NATHAN FINNEY (Santa Rosa Junior College Santa Rosa, CA 95401) MICHAEL FUERY (Laney College Oakland, CA 94607) STEVE A. GOURLAY (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

Using superposition of tilted elliptical helices, a "pure" cosine-theta dipole magnet has been designed, fabricated and tested using superconducting niobium-titanium (NbTi) wire. The geometry of the NbTi wire was held in place by careful placement of stainless steel pins in a hollow aluminum bore. The entire fabrication and testing process took 3 ½ weeks, due to the simplicity of the design. The theoretical magnetic field at a current of 267 A was calculated to be 1.07 T compared to an experimental value of 1.02 T. The tilted helical geometry yields a pure dipole, with a distribution of magnetic field strength showing uniformity along the section of highest current density. This design allows for one continuous wire to be used during the winding, making it a practical design for the rapid production of dipole magnets used in accelerators. "Pure" COS- dipole magnets can be improved by using superconducting materials with higher critical temperatures and external magnetic field tolerances allowing them to be used as insert coils.

Quality Control of Modules for the ATLAS Pixel Detector. ERIC FENG (University of California, Berkeley Berkeley, CA 94720) MAURICE GARCIA-SCIVERES (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

ATLAS is an international collaboration to build the next-generation high energy particle detector for the Large Hadron Collider at CERN. The building block of the ATLAS pixel detector is the "module", which consists of a finely pixilated silicon sensor that is indium bump-bonded to 16 front-end (FE-I3) readout chips. Each of the sensor pixels in a module is read out in parallel by an independent FE-I3 electronics channel via an indium bump bond from each sensor pixel to an FE-I3 input. Quality control of these high-precision FE-I3 chips is vital to ensure the high detector efficiency required to distinguish individual tracks among the hundreds produced every 25ns by the LHC collisions. The purpose of this study is to investigate how "dark" pixels on a module (pixels unresponsive to external charge) may be caused by defective indium bumps on the module's constituent front-end readout chips. First, a sample of bump defects discovered during visual inspection was electrically tested to see if their associated FE-I3 pixels exhibited faulty digital operation, atypically low or high threshold and noise, and too few/too many hits from the source scan. Second, an independent sample of pixels that exhibited electrical abnormalities was traced back to the visual inspection to see if their associated indium bumps had been observed to be defective. By performing cross checks of bump defects with electrical failures of modules, a rubric was constructed by which quantitative measurements of a bump defect such as bump size, shape, and spacing can be used to predict a pixel's efficiency. This rubric will increase both the efficiency and accuracy of quality control in the future.

Reconstruction of a 4D Particle Distribution Using Underdetermined Phase-Space Data. AFSHIN ROSTAMIZADEH (University of California, Berkeley Berkeley, CA 94720) ALEX FRIEDMAN (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

A well defined 4D distribution that describes the transverse spatial coordinates (x,y) and momenta (x',y') of the particles that make up an intense ion beam is of great value to theorists in the field of particle beam physics. If such a distribution truthfully captures the characteristic of the actual beam, it can be used to initialize an extensive simulation, and can yield insight into the processes that affect beam quality. Creating a proper representative distribution of particles is a challenge because the problem is, in general, quite underdetermined. Data is collected through a pair of "optical slit" diagnostics which provide two 3D distributions, f(x,y,x') and f(x,y,y'); the challenge is to coalesce these into a full 4D distribution f(x,y,x',y'). Further difficulties are introduced because the data is collected at different longitudinal planes and must be "remapped" to a common plane, taking into account the convergence or divergence of the beam as well as any off-centering. This challenge was met by developing a suitable algorithm and implementing it as a "plug-in" for the popular scientific image analysis program ImageJ, written entirely in the Java programming language. The algorithm accomplishes the desired remapping and synthesizes a 4D particle distribution, using Monte-Carlo techniques. Preliminary results show that this reconstructed distribution is consistent with actual data that was gathered from the same experiment using a different diagnostic. Also, "forward" particle-in-cell (PIC) simulations, that use the reconstructed distribution, match actual data gathered downstream in the experiment. Both these results give us some indication that the reconstruction is being done correctly. In addition to the multi-particle synthesis, the plug-in allows for the easy loading of digital data and the output of various plots that are useful to both experimenters and theorists. It also provides a framework by which its applicability can be extended to other types of experiments for which data analysis and simulation-particle synthesis are required.

Simulations of the Electron Cloud Effect for the Large Hadron Collider. VERNON CHAPLIN (Swarthmore College Swarthmore, PA 19081) MIGUEL FURMAN (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

The Large Hadron Collider (LHC), scheduled to begin operation at CERN (the European Laboratory for Particle Physics) in Switzerland in 2007, will collide counter-rotating beams of protons at unprecedented energies of up to 7 TeV per proton and intensities up to 10¹¹ protons per bunch. In this regime, a phenomenon known as the Electron Cloud Effect (ECE) is expected to play a significant role in beam dynamics. Unwanted electrons can be produced in the beam pipe through the photoelectric effect, ionization of residual gas by beam particles, or the production of secondary electrons due to electrons striking the walls. A high electron concentration partially neutralizes the beam, making it more difficult to control. The primary concern for the LHC is that electrons striking the walls of the pipe will deposit heat at a high enough rate to overwhelm the cryogenic cooling system, which is necessary for the accelerator's superconducting magnets to function properly. This paper details the results of computer simulations of the ECE in one of the LHC dipole magnets using the Fortran code POSINST, developed by Miguel Furman and Mauro Pivi at LBNL over a number of years. POSINST simulates a thin slice of the beam pipe over a time interval encompassing many bunch passages. It includes a detailed model of primary electron production, secondary emission, and electron cloud dynamics; however, it does not calculate the effects of electrons on the beam. POSINST simulations were run with bunch spacings of 25 ns and 75 ns, bunch intensities between 4 x 10¹⁰ and 1.6 x 10¹¹ protons, and maximum secondary electron yields (δ_max) between 1.0 and 2.0. Preliminary results indicate that the cooling system may be overwhelmed at the nominal values of 1.15 x 10¹¹ particles per bunch and 25 ns bunch spacing unless δ_max is less than or equal to 1.3. Independent simulations using the ECLOUD code at CERN have produced lower estimates of the average power deposition; we investigated this discrepancy by re-running our simulations with the production of re-diffused electrons turned off (ECLOUD does not consider the contribution of this effect to the population of secondaries). Results of these simulations were in close agreement with CERN results, indicating that because of their unique energy spectrum, re-diffused electrons play an important and unique role in the overall ECE.

The Universe Adventure Project. KYRA BOSTROEM (Vassar College Poughkeepsie, NY 21604) GEORGE SMOOT (Lawrence Berkeley National Laboratory, Berkley, CA, 94720)

Cosmology is a difficult area to study. It is not only constantly changing, but the ideas are abstract, often mistakes are made even by scientists in the field. However, it is also an important field to study. It tells us our history on the largest scale possible, that of the universe. It also gives us hints about our future. How then are teachers to educate themselves enough to teach students cosmology. Very few books are written below the college level and internet resources are often unreliable. The Universe Adventure is an educational website that seeks to solve these problems. Written by scientists and teachers, it is accurate, current, and at the high school and middle school level. It offers a comprehensive view of cosmology as well as quizzes throughout to test understanding and math problems to challenge students. Along with providing students with information, it also has a page of reference materials for teachers with activities and links. The website has the advantage of being as up to date with the most current models. This is due in part to the base of the website being at Berkeley lab, where there is ongoing research in cosmology. The currency is also a result of the format of the website, as a website it can easily and quickly be updated. This summer the project underwent some updates. It was edited and consolidated as well as augmented with math problems, in depth side paths, and more information. With the work done so far and future work, we hope the Universe Adventure will allow teachers to bring cosmology to their classroom in a way that is interesting and inspiring to students.