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Strangeness Production in Jets with ALICE at the LHC

At this laboratory Physicists and Engineers study fundamental particles using the world’s largest and most complex instruments. Here particles are made to collide at close to the speed of light to see how they interact and help to discover the basic laws of nature. One type of instrument used at CERN is a particle accelerator that boosts beams of particles to high energies and make them collide with either stationary particles or each other. Other types of instruments are the detectors which observe and record the collisions. CERN was founded in 1954 and sits by the France-Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 20 member states. The name CERN is an acronym for the French "Conseil Européen pour la Recherche Nucléaire", or European Council for Nuclear Research, a provisional body founded in 1952 with the mandate of establishing a world-class fundamental physics research organization in Europe. At that time, pure physics research concentrated on understanding the inside of the atom. CERN's main area of research is particle physics the study of the fundamental constituents of matter and the forces acting between them. The laboratory operated by CERN is often referred to as the European Laboratory for Particle Physics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

LDRD project 151362 : low energy electron-photon transport.

At sufficiently high energies, the wavelengths of electrons and photons are short enough to only interact with one atom at time, leading to the popular %E2%80%9Cindependent-atom approximation%E2%80%9D. We attempted to incorporate atomic structure in the generation of cross sections (which embody the modeled physics) to improve transport at lower energies. We document our successes and failures. This was a three-year LDRD project. The core team consisted of a radiation-transport expert, a solid-state physicist, and two DFT experts.

Kensek, Ronald Patrick↗

Dual-Readout Calorimetry for High-Quality Energy Measurements (Final Report)

This document constitutes the final report on the project Dual-Readout Calorimetry for High-Quality Energy Measurements. The project was carried out by a consortium of US and Italian physicists, led by Dr. Richard Wigmans (Texas tech University). This consortium built several particle detectors and tested these at the European Center for Nuclear Research (CERN) in Geneva, Switzerland. The idea arose to use scintillating crystals as dual-readout calorimeters. Such crystals were of course already known to provide excellent energy resolution for the detection of particles developing electromagnetic (em) showers. The efforts to separate the signals from scintillating crystals into scintillation and Cerenkov components led to four different methods by which this could be accomplished. These methods are based on a) the directionality, b) spectral differences, c) the time structure, and d) the polarization of the signals.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

National Computational Infrastructure for Lattice Gauge Theory: SciDAC-2 Closeout Report

Under its SciDAC-1 and SciDAC-2 grants, the USQCD Collaboration developed software and algorithmic infrastructure for the numerical study of lattice gauge theories. This work was carried out jointly by high energy and nuclear physicists within USQCD, in collaboration with applied mathematicians and computer scientists. The software and its documentation is publicly available at the USQCD software web site http://www.usqcd.org/usqcd-software. The code has been widely adopted within the United States, and is used extensively abroad. It has been instrumental in our effective use of leadership class computers, and of the dedicated computers funded for USQCD through the LQCD Computing Project. The committees which review our hardware program on a yearly basis have consistently emphasized the importance of the work done under our SciDAC grants, and the need for their continuation.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Proceedings of RIKEN BNL Research Center Workshop: The Physics of p ↑ +A Collisions at RHIC

The RIKEN BNL Research Center (RBRC) was established in April 1997 at Brookhaven National Laboratory. It is funded by the "Rikagaku Kenkyusho" (RIKEN, The Institute of Physical and Chemical Research) of Japan. The Memorandum of Understanding between RIKEN and BNL, initiated in 1997, has been renewed in 2002, 2007 and again in 2012. The Center is dedicated to the study of strong interactions, including spin physics, lattice QCD, and RHIC physics through the nurturing of a new generation of young physicists. The RBRC has both a theory and experimental component. The RBRC Theory Group and the RBRC Experimental Group consists of a total of 25-30 researchers. Positions include the following: full time RBRC Fellow, half-time RHIC Physics Fellow, and full-time postdoctoral Research Associate. The RHIC Physics Fellows hold joint appointments with RBRC and other institutions and have tenure track positions at their respective universities or BNL. To date, RBRC has over 95 graduates (Fellows and Post- docs) of which approximately 40 theorists and 20 experimenters have already attained tenure positions at major institutions worldwide. Beginning in 2001 a new RIKEN Spin Program (RSP) category was implemented at RBRC. These appointments are joint positions of RBRC and RIKEN and include the following positions in theory and experiment: RSP Researchers, RSP Research Associates, and Young Researchers, who are mentored by senior RBRC Scientists. A number of RIKEN Jr. Research Associates and Visiting Scientists also contribute to the physics program at the Center. RBRC has an active workshop program on strong interaction physics with each workshop focused on a specific physics problem. In most cases all the talks are made available on the RBRC website. In addition, highlights to each speaker’s presentation are collected to form proceedings which can therefore be made available within a short time after the workshop. To date there are over one hundred proceeding volumes available. A 10 teraflops RBRC QCDOC computer funded by RIKEN, Japan, was unveiled at a dedication ceremony at BNL on May 26, 2005. This supercomputer was designed and built by individuals from Columbia University, IBM, BNL, RBRC, and the University of Edinburgh, with the U.S. D.O.E. Office of Science providing infrastructure support at BNL. Physics results were reported at the RBRC QCDOC Symposium following the dedication. QCDSP, a 0.6 teraflops parallel processor, dedicated to lattice QCD, was begun at the Center on February 19, 1998, was completed on August 28, 1998, and was decommissioned in 2006. It was awarded the Gordon Bell Prize for price performance in 1998. QCDOC was decommissioned in May 2012. The next generation computer in this sequence, QCDCQ (600 Teraflops), is currently operational and is expected to produce many more interesting discoveries in the future.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

National Computational Infrastructure for Lattice Gauge Theory

SciDAC-2 Project The Secret Life of Quarks: National Computational Infrastructure for Lattice Gauge Theory, from March 15, 2011 through March 14, 2012. The objective of this project is to construct the software needed to study quantum chromodynamics (QCD), the theory of the strong interactions of sub-atomic physics, and other strongly coupled gauge field theories anticipated to be of importance in the energy regime made accessible by the Large Hadron Collider (LHC). It builds upon the successful efforts of the SciDAC-1 project National Computational Infrastructure for Lattice Gauge Theory, in which a QCD Applications Programming Interface (QCD API) was developed that enables lattice gauge theorists to make effective use of a wide variety of massively parallel computers. This project serves the entire USQCD Collaboration, which consists of nearly all the high energy and nuclear physicists in the United States engaged in the numerical study of QCD and related strongly interacting quantum field theories.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

HFiTT - Higgs Factory in Tevatron Tunnel

Among various options for a Higgs factory [1], a photon collider has the distinct advantage of the lowest energy requirement for an electron beam. This advantage is especially important for a circular Higgs factory, in which the synchrotron radiation power increases to the fourth power of the electron energy. For an e + e - collider, the minimum required energy per beam is 120 GeV, while for a photon collider it is 80 GeV. The corresponding ratio of synchrotron radiation power is 5 to 1. This makes it possible to consider building a photon collider at Fermilab, which will be named HFiTT, or Higgs Factory in Tevatron Tunnel. The layout is shown in Figure 1. A photon collider is based on Inverse Compton Scattering (ICS) by shooting a low energy (~3.5 eV) laser beam into a high energy (10s of GeV) electron beam to generate a back-scattered high energy (10s of GeV) photon beam for collision. The cross section for γγ → H is large and comparable to e + e - → ZH (~200 fb). Since this is an s-channel resonance, the required photon energy is low (63 GeV), corresponding to 80 GeV for an electron beam. Our design goal is 10,000 Higgs per year. If we look to the far future of electron collider technology, very high gradient acceleration techniques such as plasma wakefield acceleration are asymmetric between electrons and positrons. It is therefore important to develop a technology that will allow physicists to accelerate electrons only and still access annihilation reactions with precisely understood point-like interactions. The photon collider fills this need. This project will not only carry out important measurements of the Higgs boson properties but will also demonstrate the unique technologies needed to construct photon collider experiments at higher energies.

Chou, Weiren↗

Search for the standard model Higgs boson in $l\nu+b\bar{b}$ final states in 9.7 fb$^{-1}$ of $p\bar{p}$ collisions with the DØ detector

Humans have always attempted to understand the mystery of Nature, and more recently physicists have established theories to describe the observed phenomena. The most recent theory is a gauge quantum field theory framework, called Standard Model (SM), which proposes a model comprised of elementary matter particles and interaction particles which are fundamental force carriers in the most unified way. The Standard Model contains the internal symmetries of the unitary product group SU(3) c ⓍSU(2) L Ⓧ U(1) Y , describes the electromagnetic, weak and strong interactions; the model also describes how quarks interact with each other through all of these three interactions, how leptons interact with each other through electromagnetic and weak forces, and how force carriers mediate the fundamental interactions.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

JUSTIPEN: Japan US Theory Institute for Physics with Exotic Nuclei

JUSTIPEN is a venue for international collaboration between U.S.-based and Japanese scientists who share an interest in theory of rare isotopes. Since its inception JUSTIPEN has supported many visitors, fostered collaborations between physicists in the U.S. and Japan, and enabled them to deepen our understanding of exotic nuclei and their role in cosmos.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Proceedings of RIKEN BNL Research Center Workshop: The Approach to Equilibrium in Strongly Interacting Matter. Volume 118

The RIKEN BNL Research Center (RBRC) was established in April 1997 at Brookhaven National Laboratory*. It is funded by the ''Rikagaku Kenkyusho'' (RIKEN, The Institute of Physical and Chemical Research) of Japan and the U. S. Department of Energy’s Office of Science. The RBRC is dedicated to the study of strong interactions, including spin physics, lattice QCD, and RHIC physics through the nurturing of a new generation of young physicists. The RBRC has theory, lattice gauge computing and experimental components. It is presently exploring the possibility of an astrophysics component being added to the program. The purpose of this Workshop is to critically review the recent progress on the theory and phenomenology of early time dynamics in relativistic heavy ion collisions from RHIC to LHC energies, to examine the various approaches on thermalization and existing issues, and to formulate new research efforts for the future. Topics slated to be covered include Experimental evidence for equilibration/isotropization, comparison of various approaches, dependence on the initial conditions and couplings, and turbulent cascades and Bose-Einstein condensation.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

An Introduction to Equation of State & Shock Physics Research [Slides]

A general introduction to Equation of State (EOS) and Shock Physics Research will be presented. The goal is to provide the audience with an overall sense of what is involved in producing a complete Equation of State (single and multi-phase) and what advanced methods (DFT, QMD, etc.. ) are being utilized to better constrain the thermodynamic models. I will also present a variety of shock data results and show how these results are utilized in validating our EOS. The general interest of this work spans disciplines: Physicists, Chemists, Material Scientists, Mechanical Engineers, Geophysicists, and Applied Mathematicians.

36 MATERIALS SCIENCE↗

CERN - Six Decades of Science, Innovation, Cooperation, and Inspiration

The European Laboratory for Particle Physics, which straddles the Swiss-French border northwest of Geneva, celebrates its sixtieth birthday in 2014 CERN is the preeminent particle-physics institution in the world, currently emphasizing the study of collisions of protons and heavy nuclei at very high energies and the exploration of physics on the electroweak scale (energies where electromagnetism and the weak nuclear force merge). With brilliant accomplishments in research, innovation, and education, and a sustained history of cooperation among people from different countries and cultures, CERN ranks as one of the signal achievements of the postwar European Project. For physicists the world over, the laboratory is a source of pride and inspiration.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Proceedings of RIKEN BNL Research Center Workshop: Thermal Photons and Dileptons in Heavy-Ion Collisions. Volume 119

The RIKEN BNL Research Center (RBRC) was established in April 1997 at Brookhaven National Laboratory. It is funded by the ''Rikagaku Kenkyusho'' (RIKEN, The Institute of Physical and Chemical Research) of Japan and the U. S. Department of Energy’s Office of Science. The RBRC is dedicated to the study of strong interactions, including spin physics, lattice QCD, and RHIC physics through the nurturing of a new generation of young physicists. The RBRC has theory, lattice gauge computing and experimental components. It is presently exploring the possibility of an astrophysics component being added to the program. The primary theme for this workshop related to sharing the latest experimental and theoretical developments in area of low transverse momentum (p T ) dielectron and photons. All the presentations given at the workshop are included in this proceedings, primarily as PowerPoint presentations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Quantum Electronic Matter in Two Dimensions

Most often, the electrical properties of a material are described as either "conducting" or "insulating". Copper, everyone knows, is a good conductor. It is the foundation of the electrical infrastructure of the nation. Glass, on the other hand, is an excellent insulator. But do these two words describe all the possibilities? The answer is emphatically no, and the basic subject of the research funded by this grant is aimed at fleshing out a more complete description of the electrical properties of materials. Many people are aware that there are also special materials called superconductors. A superconductor (e.g. aluminum when cooled to very low temperatures) is like a regular conductor except that it conducts electricity with no energy loss at all. Ordinary metals get hot when current flows through them; witness the toaster in your kitchen. In a superconductor something very special is going on: The electrons in the metal don't behave individually as they do in an ordinary conductor. Instead they act collectively. It is this collective aspect that makes superconductors so interesting to physicists. So now we have metals, insulators and superconductors. Is there anything else? We now know the answer is yes. In this research we examine special conducting materials, ones in which the mobile electrons are confined to move on a plane surface (as opposed to motion in all three directions). Examples of such "2D" materials include electrons confined to the interface between two otherwise insulating materials (as in the so-called "semiconductor heterostructures" used here) and the single atomic layer of carbon atoms now known as "graphene". Materials like these are not just museum curiosities; each of the billions of transistors in every smart-phone has a 2D electron system in it. In the work supported by this grant, the focus is on both collective conducting states in semiconductor heterostructures and on the conducting properties of graphene and its few-layer cousins. In particular, the exotic collective (and deeply quantum mechanical) electronic phases which develop when a large magnetic field is applied have been a major focus of effort. Significant results have been obtained from both ordinary electrical measurements and from more sophisticated thermoelectric studies of such systems. Related studies of few-layer graphenes have elucidated the transition from the two- to three-dimensional electrical properties of carbon-based conductors. Investigations like these expand our understanding of electronic materials general. While there are certainly immediate fundamental scientific pay-offs, it is also true that research of this kind ultimately leads to technological breakthroughs in the long term. By way of example, superconductivity was undoubtedly regarded as a useless novelty when it was discovered in 1911. Who could have known then that it would become crucial to the medical revolution brought about by magnetic resonance imaging decades later?

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems

These funds were used for partial support of the PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems, that was held on 8-11 August, 2013, at Washington University, St. Louis, MO. This conference, held in conjunction with the 16th International Congress on Photosynthesis/St. Louis, continued a long tradition of light-harvesting satellite conferences that have been held prior to the previous six international photosynthesis congresses. In this Workshop, the basis was explored for the current interest in replacing fossil fuels with energy sources derived form direct solar radiation, coupled with light-driven electron transport in natural photosynthetic systems and how they offer a valuable blueprint for conversion of sunlight to useful energy forms. This was accomplished through sessions on the initial light-harvesting events in the biological conversion of solar energy to chemically stored energy forms, and how these natural photosynthetic processes serve as a guide to the development of robust bio-hybrid and artificial systems for solar energy conversion into both electricity or chemical fuels. Organized similar to a Gordon Research Conference, a lively, informal and collegial setting was established, highlighting the exchange of exciting new data and unpublished results from ongoing studies. A significant amount of time was set aside for open discussion and interactive poster sessions, with a special session devoted to oral presentations by talented students and postdoctoral fellows judged to have the best posters. This area of research has seen exceptionally rapid progress in recent years, with the availability of a number of antenna protein structures at atomic resolution, elucidation of the molecular surface architecture of native photosynthetic membranes by atomic force microscopy and the maturing of ultrafast spectroscopic and molecular biological techniques for the investigation and manipulation of photosynthetic systems. The conferees represented a diverse international and multidisciplinary group, with over 160 individuals attending from a total of 17 different countries. Attendees came from a wide range of fields assuring that the widest possible interdisciplinary exchanges. They included prominent biochemists, biophysicists, plant physiologists, chemical physicists, as well as theoretical and computational physical chemists, who presented their research findings or to hear the latest advances in this very dynamic field. In the choice of speakers, a balance was created between established scientists and young, emerging researchers, given this opportunity to showcase their results. Sessions were held on electronic and vibrational coherence including coherent sharing of excitations among donor and acceptor molecules during excitation energy transfer, nonphotochemical quenching, acclimation to light environments, evolution, adaptation and biodiversity of light-harvesting pigment-protein complexes, their structure and membrane organization, spectroscopy and dynamics, as well as artificial antenna systems. A joint session was also held with the participants from the Cyanobacterial Satellite Conference. A special issue of Photosynthesis Research devoted to light harvesting (Volume 121, Issue No. 1, July 2014) has recently appeared which contains peer-reviewed original research contributions arising from talks and posters presented at the PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems. Edited by the Organizers of the Workshop, Robert E. Blankenship, Harry A. Frank and Robert A. Niederman, it includes topics ranging from the isolation of new bacteriochlorophyll species from green bacteria, temperature effects on the excited states of the newly discovered chlorophyll (Chl) ƒ, new architectures for enhancing energy capture by biohybrid light-harvesting complexes, forces governing the formation of light-harvesting rings, spectroscopy of carotenoids of algae and diatoms and the supramolecular organization of caroteno-Chl proteins in diatoms, the molecular basis for urea dissociation of phycocyanin trimers and the role of vibronic molecular excitation theory in describing the spectral dynamics of pigment-protein complexes.

14 SOLAR ENERGY↗

Belle-II Experiment Network Requirements

The Belle experiment, part of a broad-based search for new physics, is a collaboration of ~400 physicists from 55 institutions across four continents. The Belle detector is located at the KEKB accelerator in Tsukuba, Japan. The Belle detector was operated at the asymmetric electron-positron collider KEKB from 1999-2010. The detector accumulated more than 1 ab-1 of integrated luminosity, corresponding to more than 2 PB of data near 10 GeV center-of-mass energy. Recently, KEK has initiated a $400 million accelerator upgrade to be called SuperKEKB, designed to produce instantaneous and integrated luminosity two orders of magnitude greater than KEKB. The new international collaboration at SuperKEKB is called Belle II. The first data from Belle II/SuperKEKB is expected in 2015. In October 2012, senior members of the Belle-II collaboration gathered at PNNL to discuss the computing and neworking requirements of the Belle-II experiment with ESnet staff and other computing and networking experts. The day-and-a-half-long workshop characterized the instruments and facilities used in the experiment, the process of science for Belle-II, and the computing and networking equipment and configuration requirements to realize the full scientific potential of the collaboration's work.

43 PARTICLE ACCELERATORS↗

Final Report for Grant DOE DE-FG02-08ER64573 (Relating to Turbulence Modeling)

Turbulence enhances transport and mixing. Turbulent ocean currents can increase the encounter rate between fish larvae and their prey. Without turbulence, the fuel and air injected into the cylinder of an internal combustion engine would mix too slowly to be effective. Birds extract energy from turbulent winds to soar for great distances without flapping their wings. Turbulence can be detrimental as well. The efficiencies of vehicles, pipelines, and industrial equipment are all hindered by turbulence. Turbulence can also cause structural fatigue, generate unwanted noise, and distort the propagation of electromagnetic signals. These observations highlight the importance of turbulence research. Our ability to predict and control turbulence and, thus, to intensify or suppress its effects as circumstances warrant is contingent on our understanding of the underlying mechanisms. Turbulence is also immensely interesting from a purely scientific perspective and is a great source of fundamentally important, challenging problems for physicists, engineers, and mathematicians. Moreover, various methods and tools developed in the field have found applications in other fields, including nonlinear optics, nonlinear acoustics, pattern formation, image processing, data compression, and econophysics. It is possible, at least away from walls, to derive LES models of very high-order accuracy. However, these models also lead to correspondingly intense computational complexity for their numerical solution. Some also introduce yet more questions on the already difficult problem of specifying needed and sometimes artificial local boundary conditions for the inherently nonlocal flow averages. For these two (and other) reasons, there has been a resurgence of interest in basing simulations of turbulent flows on much simpler regularizations of the Navier–Stokes equations rather than on full models of local averages--i.e., LES models. Initially these were developed as pure theoretical tools. The influx of ideas from LES and the added constraint that the regularization be amenable to numerical simulation have breathed new perspective and thus new life into this thread of ideas.Over the past year, a significant portion of our research activity has focused on numerical studies of the Navier–Stokes-$αβ$ model and extensions thereof. Our results regarding these and other approaches to turbulence modeling are described below.

97 MATHEMATICS AND COMPUTING↗

Federal Radiological Monitoring and Assessment Center (FRMAC) Assessment Manual, Volume 1: Overview and Methods

The Federal Radiological Monitoring and Assessment Center (FRMAC) Assessment Manual is the tool used to organize and guide activities of the FRMAC Assessment Division. The mission of the FRMAC Assessment Division in a radiological emergency is to interpret radiological data and predict worker and public doses. This information is used by Decision Makers to recommend protective actions in accordance with Protection Action Guides (PAGs) issued by government agencies. This manual integrates many health physics tools and techniques used to make these assessments. Volume 1 contains the scientific bases and computational methods for assessment calculations. These calculations are broken up into sections: Section 1 – Public Protection; Section 2 – Emergency Worker Protection; Section 3 – Ingestion Pathway Analysis; and, Section 4 – Supplemental Methods. FRMAC’s broad-based staff is the key to achieving Assessment's objectives. The staff is drawn from multiple agencies and has a variety of skills. The staff includes health physicists, data analysts, cartographers, modelers, meteorologists, and computer scientists. These professionals facilitate the analysis, interpretation, presentation and preservation of incident specific radiological data. These individuals are primarily drawn from the NNSA and the EPA. However, staff also includes members from the NRC, USDA, FDA, CDC, and other Federal agencies. State, Local, and Tribal scientific specialists are also invited to participate.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗