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Propose an innovative concept of simultaneous beam delivery to several hadrontherapy treatment rooms, based on a technology of multiple-extraction fixed-field synchrotron accelerator, and on adapted hospital architecture. This concept will reduce treatment cost, bring it closer to conventional X-ray cost, making hadronthrapy accessible to greater number of patients.
In this report, we summarize the research in physics of elementary particles conducted by the Florida Tech DOE supported group at the CMS experiment at CERN, during the last 3-year cycle under this grant.
In this thesis I report on several results obtained from an accurate analysis of the $Bhh$ data sample: Annihilation decay modes: using 6 fb$^{-1}$ of data collected by the CDF experiment, I obtained the first evidence of the $B_s^0\to \pi^+ \pi^-$ decay mode, with a significance of about 3.7$\sigma$, and I performed the most precise measurement of the Branching Ratio of the $B_d^0\to K^+ K^-$ decay mode at the time, corresponding to an excess of 2$\sigma$ level. These measurements have important consequences as discussed in the previous sections: the comparison between these branching fractions and the theoretical predictions provides unique information for tuning the phenomenological models. Our results prompted intense theoretical work both using pQCD and QCDF approaches to accommodate the discrepancies between predictions and experimental results. CP violation: using the full CDF 10 fb$^{-1}$ of data collected by the CDF experiment, I found evidence of the \textbf{CP violation} of $B_s^0 \to K \pi$ decay mode, with a significance of 3$\sigma$, confirming the result recently obtained at LHCb. I also measured the CP asymmetries of the $B_d^0 \to K \pi$ decay modes, in agreement and of comparable resolution with the b-factories experiments, while the most precise measurement up to date is from LHCb. The precision reached in the Acp($B_s^0 \to K \pi$ ) measurement gives the possibility to perform interesting checks of the Standard Model predictions, explained in the previous sections. I also obtained the world's best measurements of the CP asymmetries in $\Lambda_b^0 \to p\pi$ and $\Lambda_b^0 \to pK$ decay modes. These measurements are unique and represent a step forward in the understanding of the \CP\ violation phenomena in the relatively unexplored $\Lambda_b^0$ sector.
We have irradiated NdFeB permanent magnet samples from different manufacturers and with differing values of coercivity and remanence using stepped doses of 1 MeV equivalent neutrons up to a fluence of 0:64 1015n=cm2 to evaluate effects on magnetization and B field distributions. The samples with high coercivity, irradiated in open circuit configurations, showed no or minimal effects when compared with unirradiated samples, whereas the lower coercivity magnets suffered significant losses of magnetization and changes in the shapes of their field patterns. One such magnet underwent a fractional magnetization loss of 13.1% after a fluence of 0:59 1015 n=cm2. This demagnetization was not uniform. With increasing fluence, B field scans along the centerlines of the pole faces revealed that the normal component of B decreased more near the midpoint of the scan than near the ends. In addition, a fit to the curve of overall magnetization loss with fluence showed a significant deviation from linearity. The results are discussed in light of other measurements and theory. The high coercivity materials appear suitable for use in accelerator applications subject to irradiation by fast neutrons such as dipoles where the internal demagnetizing field is comparable to or less than that of the open circuit samples tested in this study.
Abstract Not Provided
The UTA High Energy Physics Group conducted generic detector development based on large area, very thin and high sensitivity gas detector using gas electron multiplier (GEM) technology. This is in preparation for a use as a sensitive medium for sampling calorimeters in future collider experiments at the Energy Frontier as well as part of the tracking detector in Intensity Frontier experiments. We also have been monitoring the long term behavior of one of the prototype detectors (30cmx30cm) read out by the SLAC-developed 13-bit KPiX analog chip over three years and have made presentations of results at various APS meetings. While the important next step was the development of large area (1m x 1m) GEM planes, we also have looked into opportunities of applying this technology to precision tracking detectors to significantly improve the performance of the Range Stack detector for CP violation experiments and to provide an amplification layer for the liquid Argon Time Projection Chamber in the LBNE experiment. We have jointly developed 33cmx100cm large GEM foils with the CERN gas detector development group to construct 33cm x100cm unit chambers. Three of these unit chambers will be put together to form a 1m x 1m detector plane. Following characterization of one 33cmx100cm unit chamber prototype, a total of five 1m x 1m planes will be constructed and inserted into an existing 1m3 RPC DHCAL stack to test the performance of the new GEM DHCAL in particle beams. The large area GEM detector we planned to develop in this proposal not only gives an important option to DHCAL for future collider experiments but also the potential to expand its use to Intensity Frontier and Cosmic Frontier experiments as high efficiency, high amplification anode planes for liquid Argon time projection chambers. Finally, thanks to its sensitivity to X-rays and other neutral radiations and its light-weight characteristics, the large area GEM has a great potential for the use in medical imaging and homeland security, as well as satellite based astronomy experiments.
There is a synergy between the fields of Beam Dynamics (BD) in modern particle accelerators and Applied Mathematics (AMa). We have formulated significant problems in BD and have developed and applied tools within the contexts of dynamical systems, topological methods, numerical analysis and scientific computing, probability and stochastic processes, and mathematical statistics. We summarize the three main areas of our AMa work since 2011. First, we continued our study of Vlasov-Maxwell systems. Previously, we developed a state of the art algorithm and code (VM3@A) to calculate coherent synchrotron radiation in single pass systems. In this cycle we carefully analyzed the major expense, namely the integral-over-history (IOH), and developed two approaches to speed up integration. The first strategy uses a representation of the Bessel function J0 in terms of exponentials. The second relies on “local sequences” developed recently for radiation boundary conditions, which are used to reduce computational domains. Although motivated by practicality, both strategies involve interesting and rather deep analysis and approximation theory. As an alternative to VM3@A, we are integrating Maxwell’s equations by a time-stepping method, bypass- ing the IOH, using a Discontinuous Galerkin (DG) method. DG is a generalization of Finite Element and Finite Volume methods. It is spectrally convergent, unlike the commonly used Finite Difference methods, and can handle complicated vacuum chamber geometries. We have applied this in several contexts and have obtained very nice results including an explanation of an experiment at the Canadian Light Source, where the geometry is quite complex. Second, we continued our study of spin dynamics in storage rings. There is much current and proposed activity where spin polarized beams are being used in testing the Standard Model and its modifications. Our work has focused on invariant spin fields (ISFs) and amplitude dependent spin tunes (ADSTs), which are essential for estimating beam polarization. Several algorithms have been developed since the 1980s for computing the ISF, among them the Heinemann- Hoffstaetter method of stroboscopic averaging (SA) which is implemented in the code SPRINT. SA, which computes the ISF by using spin tracking data, can find the ISF to computer precision if it exists and thus can give evidence for existence of the ISF. Central to our work is resolving the ISF conjecture, which says that, off orbital resonance, an ISF exists. Thus Heinemann developed, in his 2010 PhD thesis, a new framework which unifies and generalizes the notions of ISF and ADST by using bundle theory. This lead to a long paper which was a major collaborative effort during the recent cycle. In a nutshell, our bundle approach elegantly unifies the dynamics of spin-1/2 and spin-1 particles, e.g., protons and deuterons. In fact it is well known that these two kinds of dynamics are driven by the same spin transfer matrix and in our approach one sees the deeper reason for this: the spin transfer matrix carries the natural dynamics of a principal bundle whereas the difference between the spin-1/2 and spin-1 dynamics lies in their different geometrical situation, i.e., different underlying associated bundles. Thus one arrives at new results for polarized beams, among them the Invariant Reduction Theorem (IRT) and the Cross Section Theorem (CST). The IRT gives a necessary and sufficient condition for the ISF to exist. The SA technique revealed, 20 years ago, that each ISF can be viewed as a complex agglomerate of spin tracking data. The bundle approach goes one step further by using the IRT and the CST to glue spin tracking data into agglomerates which are candidates for ISFs. We gain insight because the “good” agglomerates, in the presence of an ISF, are very different from the “bad” ones. Finally we mention that the bundle approach has analogies to the approach used in geometrical Yang-Mills theory. Third, we studied X-Ray Free Electron Lasers (FELs), which are electron accelerators producing coherent undulator radiation over a wide range of frequencies from microwaves to x-rays. The photon beams produced in FEL undulators are used to study material samples in biology, material science etc. We developed a mathematical analysis, based on the 6D Lorentz system, of energetic electrons moving through a planar undulator excited by a Maxwell traveling wave field of wavelength λ. Our Method of Averaging perturbation analysis yields non-resonant and near-to-resonant normal form approximations as a function of λ, which we present in two averaging theorems. We prove the theorems in detail, error bounds and giving a tutorial on mathematically rigorous perturbation theory in a context where proofs are easily understood. To our knowledge the planar problem has not been analyzed with the generality here nor has the standard FEL pendulum system, which appears on resonance, been derived with error bounds. In addition to the domains of validity of the normal forms we obtain new insights that require further study, including a more general low gain theory. With a firm foundation in the non-collective case above we are studying the 3D collective case from start up from noise to high gain and saturation. We have formulated the noise start up as a problem of going from the microscopic Klimontovich-Maxwell to the macroscopic Vlasov-Maxwell with a Vlasov correction term. In the 1D setting, we seek an alternative to the phenomenological Vlasov approach which models shot noise by a perturbation on an initial “smooth” density. The 1D wave equation with a Klimontovich source is often the starting point for the 1D FEL high gain theory. We have a new representation of solutions which may lead to new insights.
We describe formal work that relates the nite-volume spectrum in a quantum eld theory to scattering and decay amplitudes. This is of particular relevance to numerical calculations performed using Lattice Quantum Chromodynamics (LQCD). Correlators calculated using LQCD can only be determined on the Euclidean time axis. For this reason the standard method of determining scattering amplitudes via the Lehmann-Symanzik-Zimmermann reduction formula cannot be employed. By contrast, the nite-volume spectrum is directly accessible in LQCD calculations. Formalism for relating the spectrum to physical scattering observables is thus highly desirable. In this thesis we develop tools for extracting physical information from LQCD for four types of observables. First we analyze systems with multiple, strongly-coupled two-scalar channels. Here we accommodate both identical and nonidentical scalars, and in the latter case allow for degenerate as well as nondegenerate particle masses. Using relativistic eld theory, and summing to all orders in perturbation theory, we derive a result relating the nite-volume spectrum to the two-to-two scattering amplitudes of the coupled-channel theory. This generalizes the formalism of Martin L uscher for the case of single-channel scattering. Second we consider the weak decay of a single particle into multiple, coupled two-scalar channels. We show how the nite-volume matrix element extracted in LQCD is related to matrix elements of asymptotic two-particle states, and thus to decay amplitudes. This generalizes work by Laurent Lellouch and Martin L uscher. Third we extend the method for extracting matrix elements by considering currents which insert energy, momentum and angular momentum. This allows one to extract transition matrix elements and form factors from LQCD. Finally we look beyond two-particle systems to those with three-particles in asymptotic states. Working again to all orders in relativistic eld theory, we derive a relation between the spectrum and an in nite-volume three-to-three scattering quantity. This nal analysis is the most complicated of the four, because the all-orders summation is more di cult for this system, and also because a number of new technical issues arise in analyzing the contributing diagrams.
The GW Data Analysis Center (DAC) has made significant progress in its program to enhance and expand the partial-wave and multipole analyses of fundamental reactions, while maintaining and expanding each associated database. These efforts provide guidance to national and international experimental and theoretical efforts, and are an important link between theory and experiment. Our principal goals are focused on baryon and meson physics programs and related topics.
The main emphasis of the entire project is on issues having to do with medium energy and ultra-relativistic energy and heavy ion collisions. A major goal of both theory and experiment is to study properties of hot dense nuclear matter under various extreme conditions and to map out the phase diagram in density or chemical potential and temperature. My studies in medium energy nuclear collisions focused on the liquid-gas phase transition and cluster yields from such transitions. Here I developed both the statistical model of nuclear multi-fragmentation and also a mean field theory.
Jet physics is an exciting and rapidly growing branch of particle physics, particularly relevant to the energy frontier. Just a few years ago, jets were universally treated as structureless objects, representing the momentum of an underlying quark or gluon. Nowadays, jets are understood to be intricate, dynamical objects with interesting hidden properties worthy of investigation and relevant for understanding quantum field theory.
Implications of the LHC top Higgs mass measurements for vacuum stability, and the topic of jet physics.
Precision measurements offer important, low-energy tests of the Standard Model. The Qweak and (proposed) MOLLER experiments at Jefferson Lab are two such measurements. Since the interpretation of the experimental results depends on the precision of the theory prediction, radiative corrections need to be properly accounted for. In this thesis we examine the γZ box correction to the the weak charge of the proton.
This project was part of a coordinated software development effort which the nuclear physics lattice QCD community pursues in order to ensure that lattice calculations can make optimal use of present, and forthcoming leadership-class and dedicated hardware, including those of the national laboratories, and prepares for the exploitation of future computational resources in the exascale era. The UW team improved and extended software libraries used in lattice QCD calculations related to multi-nucleon systems, enhanced production running codes related to load balancing multi-nucleon production on large-scale computing platforms, and developed SQLite (addressable database) interfaces to efficiently archive and analyze multi-nucleon data and developed a Mathematica interface for the SQLite databases.
The kaon electroproduction cross section was extracted from data from the E93-018 and the E01-004 (FPI-2) experiments taken at the Thomas Jefferson National Accelerator Facility in the p(e,e'K + )Λ channel. The cross section was fully separated into longitudinal, transverse, and two interference components at four-momentum transfers Q 2 of 1.0 (GeV/c) 2 (with center of mass energy W=1.81 GeV), 1.36 and 2.07 (GeV/c) 2 (W=2.31 GeV). The kaon form factor (FK) was extracted from the longitudinal cross section in these kinematics using the Regge model by Vanderhaeghen, Guidal, and Laget. Results show F K to be systematically lower than the empirical monopole form, although still compatible with this form within the estimated uncertainties. The resulting kaon form factor values were combined with the world pion and kaon form factor data to extract the transverse change densities of the pion and kaon. These were compared to that of the proton, showing a possible experimental glimpse of the transition between the proton core and the meson cloud in terms of transverse densities.
The goal of the research of the William and Mary group (PI from Computer Science and Co-PI from Physics) is to develop algorithms that address the limitations in computational scalability of current methods in lattice QCD. Of particular interest is the problem of computing traces of certain functions of a matrix, which arises in nuclear physics calculations of disconnected diagrams and requires the solution of a large number of linear systems of equations.
DOE award DE-SC0007863 supports theoretical research in high energy physics. PI and students are NOT a part of any experimental collaboration, even if some works were done in collaboration with experimental colleagues. All research products are in the form of research articles and they are publicly available under inspirehep.net and arxiv.org, which are typical publication methods in high energy physics. No invention or patent is involved with this research. No equipment or hardware is involved with the research under this award (beside a laptop purchased with PI's startup). Some of research outcome is in the form of a computer code, which is available in https://launchpad.net/maddm. This is community effort and anyone has access to the program. Its source is open and anyone can participate in the development. Research outcomes and the code are used by colleagues in high energy physics, including both theorists and experimentalists. Therefore the outcome of research topics under this award supported the High Energy Physics experimental research program, both in understanding the data and in finding new directions for experimental exploration. The research materials are used to train undergraduate students, graduate students and postdoctoral scholars. We summarize research activity under this award in the following section and major products are listed in section 3. Section 4 contains professional presentations given by PI. Other products developed during the award period are in section 5. Summary of expenses, and student/postdoc support are summarized in section 6 and 7, respectively.
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