123257721
The stringless gauge potential of accelerated monopole
SummaryIn this paper, we get theU1 potential without singular string for an accelerated magnetic pole. To obtain this we find its equivalentSU2 potential, which could be expressed by anU1-invariant section of theSU2/U1 coset bundle. Then we could superpose linearly the correspondingU1 potentials to get the potential of an accelerated system of monopoles and electric charges in the general case. By the way, we also discuss the criterion forU1 field to be in one-to-one correspondence with anU1-invariant section and the condition for aSU2 field to be reducible to anU1 field.RiassuntoIn questo lavoro si ottiene il potenzialeU1 senza stringa singolare per un monopolo magnetico accelerato. Per ottenerlo si trova il suo potenziale equivalenteSU2, che può essere espresso mediante una sezione invariante rispetto aU1 del fascio del coinsiemeSU2/U1. Si piò allora sovrapporre linearmente i corrispondenti potenzialiU1 per ottenere il potenziale del sistema accelerato di monopoli e le cariche elettriche nel caso generale. A questo proposito, si discute anche il criterio per cui il campoU1 è in corrispondenza 1-1 con una sezione invariante rispetto aU1 e la condizione per cui un campoSU2 è riducibile ad un campoU1.РезюмеВ этой статье мы получаемU1 потенциал без сингулярной струны для ускоренного монополя. Для получения этого потенциала мы находим эквивалентный емуSU2 потенциал, который может быть выражен черезU1 инвариантное сечениеSU2/U1 семейства смежного класса. Затем мы получаем линейную суперпозицию соответствующихU1 потенциалов, чтобы получить потенциал для ускоренной системы монополей и электрических зарядов в общем случае, мы также обсуждаем критерий, чтобы полеU1 находилось в однозначном соответствии сU1 инвариантным сечением, и условие, чтобы полеSU2 могло быть сведено к полюU1.
124174398
Local Symmetry and Conserved Currents of Principal Chiral Model with Topological Term
In this paper we show the scattering problem's equation of principal chiral model with Wess-Zumino-Witten term. Two sets of symmetry transforms are given and four series of conserved currents are obtained, in which two of them are Noether types and the others are not. Finally the Kac-Moody algebra is discussed.
55450732
WiZard 2: a proposal to complement WiZard detector with two further modules of tracking calorimeter and an accurate spark counter t.o.f. system
Among the several existent proposals for the cosmic antimatter search, the Wi#x005A-0304;ard project for the U.S. Space Station Freedom shows the greatest interest. A possible upgrading of the Wi#x005A-0304;ard apparatus, called Wi#x005A-0304;ard 2, is presented in order to sensibly improve the capability of detecting antihelium nuclei in the cosmic radiation. 
Fra tutte le varie proposte esistenti nell’ambito della ricerca di antimateria cosmica, il progetto Wi#x005A-0304;ard per la Stazione Spaziale americana Freedom si dimostra del piu grande interesse. Si presenta un possibile ampliamento dell’apparato Wi#x005A-0304;ard allo scopo di migliorare sensibilmente la capacita di rivelare nuclei di antielio nella radiazione cosmica.
119797946
Application of silicon-detector technology to experiments in space. An option for the Astromag facility
SummaryCosmic antimatter search needs transportation systems of the apparatus outside the atmosphere. The Astromag facility on the NASA space station will be a great opportunity for such a search in the next future. Here we discuss the advantages achievable from silicon-detector technology in space research and we propose a silicon calorimeter as an ideal option to work in connection with the Astromag facility itself.RiassuntoLa ricerca di antimateria cosmica necessita di sistemi di trasporto e di apparati al di fuori dell’atmosfera. La facility Astromag, posta sulla stazione spaziale della NASA, costituirà nel prossimo futuro una grande opportunità per questo tipo di ricerca. Si discutono qui i vantaggi che si possono ottenera dalla tecnologia dei rivelatori a silicio nella ricerca spaziale e si propone un calorimetro a silicio come opzione ideale per operare in connessione con la facility Astromag stessa.РезюмеПоиски антивещества в космосе требуют транспортных систем для вывода экспериментальной аппаратуры за пределы атмосферы. Экспериментальная установка «АСТРОМАГ» на космической станции NASA представляет болышие возможности для таких поисков. Мы обсуждаем преимущества технологии кремниевых детекторов в космических исследованиях. Предлагается кремниевый калориметр, как идеальный прибор для установки «АСТРОМАГ».
73704898
A New Design for ILC 3.2 km Damping Ring Based on FODO Cell
In this paper, we made a new design for ILC 3.2 km damping ring with 2 arcs based on FODO cell and 2 straight sections which are nearly the same as the new version of the 6.4 km ring DCO4 [1]. This new lattice uses less magnets than DCO4 and less quadrupoles than the present SuperB like lattice [1], and has a freely tunable momentum compaction factor. The work of lattice design and dynamic aperture study will be presented in detail. INTRODUCTION After ILC enter the Technical Design Phase 1 by the end of 2008, the Minimum Machine study [2] based on RDR baseline was launched as the essential strategy of cost-reduction. The term “minimum machine” which try to redesign the machine does not refer to any definable true minimum, but instead is a euphemism for higher level alternative design concepts which promise significant cost-reduction while maintaining the machine performance. With the new machine parameter, a reduction in the number of bunches by a factor of two allows a reduction by the same factor in the circumference of the damping ring, while keeping the current (bunch spacing) in the rings constant. To first order, this could result in a reduction of the damping rings’ cost by almost a factor of two. However, the actual cost savings will depend on the exact lattice design. The design study of ILC 6 km damping ring has started very early and gone through intense competition. The 6.4 km DCO4 based on FODO arc cell is the final version adopted by RDR baseline in 2008. But for the 3.2 km ring, the study which was started by the end of 2008 seems to be immature. The only existent design for the smaller ring is DSB3 based on SuperB lattice. Considering the advantage of FODO lattice such as smaller number of quadrupoles and sextupoles per cell, freely tuable momentum compaction, and better dynamic aperture, we try to make a new design for the smaller ring using FODO arc cell which can also provide a reference for DSB3 design. We named our new design as DMC1 for convenience. GLOBAL CONSIDERATION AND PARAMETER CALCULATION In our design, we adopted the racetrack structure as the 6.4 km baseline design (DCO4). The layout of our 3.2 km damping ring is shown in Figure 1 with the electron and positron beams counter-rotating in the two rings. The advantage of this kind of structure is that the ————————————— injection and extraction beam lines for e+ and erings can be in the same tunnel. Also, the rf section and wigglers are located near each other in order to minimize cryogenic transfer lines, while the rf section must be upstream to avoid the radiation damage. Figure 1: Layout of the 3.2 km ILC damping ring. The first parameter should be considered before lattice design is the damping time. ILC damping ring has a very fast damping time (about 25 ms) which is decided by the 5 Hz machine repetition rate. The damping time for a damping ring is given by [3]
119295443
RESIDUAL ENERGY IN MAGNETOHYDRODYNAMIC TURBULENCE
There is mounting evidence in solar wind observations and in numerical simulations that kinetic and magnetic energies are not in equipartition in magnetohydrodynamic (MHD) turbulence. The origin of their mismatch, the residual energy Er = Ev – Eb , is not understood well. In the present work this effect is studied analytically in the regime of weak MHD turbulence. We find that residual energy is spontaneously generated by turbulent dynamics, and it has a negative sign, in good agreement with the observations. We find that the residual energy condenses around k || = 0 with its k ||-spectrum broadening linearly with k ⊥, where k || and k ⊥ are the wavenumbers parallel and perpendicular to the background magnetic field, and the field-perpendicular spectrum of the residual energy has the scaling Er (k ⊥)∝k –1 ⊥ in the inertial interval. These results are found to be in agreement with numerical simulations. We propose that residual energy plays a fundamental role in Alfvenic turbulence and it should be taken into account for the correct interpretation of observational and numerical data.
9471313
SciDAC advances in beam dynamics simulation: from light sources to colliders
In this paper, we report on progress that has been made in beam dynamics simulation, from light sources to colliders, during the first year of the SciDAC-2 accelerator project 'Community Petascale Project for Accelerator Science and Simulation (ComPASS).' Several parallel computational tools for beam dynamics simulation are described. Also presented are number of applications in current and future accelerator facilities (e.g., LCLS, RHIC, Tevatron, LHC, and ELIC).