118648616
Heavy Flavor Physics Through e-Science
Heavy flavor physics is an important element in understanding the nature of particle physics. Accurate knowledge of the properties of heavy flavor physics plays an essential role for the determination of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. An asymmetric-energy e + e B factory KEKB and its experiment Belle is under way. It will be upgraded to Super Belle in a few years, and the size of the B meson sample will be dramatically increased. Also, the data size of Tevatron experiments (CDF, D0) are on the order of Peta Byte (PB). Therefore, we need to use a new concept of e-Science in this area. This concept implies studying a huge size of data from heavy flavor physics anytime and anywhere even if we are not on-site in accelerator laboratories. The components of this concept include data production, data processing, and data analysis. We apply this concept to the current CDF experiment at Tevatron. We will expand this concept to Super Belle and large hadron collider (LHC) experiments, which will achieve an accuracy of measurements in the next decades.
15169434
Optimizing Large Data Transfers over 100Gbps Wide Area Networks
The Advanced Networking Initiative (ANI) project from the Energy Services Network provides a 100 Gbps test bed, which offers the opportunity for evaluating applications and middleware used by scientific experiments. This test bed is a prototype of a 100 Gbps wide-area network backbone, which links several Department of Energy (DOE) national laboratories, universities and other research institutions. These scientific experiments involve movement of large datasets for collaborations among researchers at different sites and thus require advanced infrastructure for supporting large and fast data transfers. A 100 Gbps network test bed is a key component of the ANI project and is used for DOE's science research programs. This work presents results towards obtaining maximum throughput in large data transfers by optimizing and fine-tuning scientific applications and middleware to use this advanced infrastructure efficiently. A detailed performance evaluation is discussed measuring both applications, from High Energy Physics (HEP) and from data transfer middleware (GridFTP, Globus Online, Storage Resource Management, XrootD and Squid) at 100 Gbps speeds and 53 ms of latency. Results show that up to 97% efficiency of such high bandwidth high latency network is possible, achieving 80-90 Gbps in most test cases with a peak transfer rate of 100 Gbps.
54966387
Identifying Gaps in Grid Middleware on Fast Networks with the Advanced Networking Initiative
As of 2012, a number of US Department of Energy (DOE) National Laboratories have access to a 100 Gb/s wide-area network backbone. The ESnet Advanced Networking Initiative (ANI) project is intended to develop a prototype network, based on emerging 100 Gb/s Ethernet technology. The ANI network will support DOE's science research programs. A 100 Gb/s network test bed is a key component of the ANI project. The test bed offers the opportunity for early evaluation of 100Gb/s network infrastructure for supporting the high impact data movement typical of science collaborations and experiments. In order to make effective use of this advanced infrastructure, the applications and middleware currently used by the distributed computing systems of large-scale science need to be adapted and tested within the new environment, with gaps in functionality identified and corrected. As a user of the ANI test bed, Fermilab aims to study the issues related to end-to-end integration and use of 100 Gb/s networks for the event simulation and analysis applications of physics experiments. In this paper we discuss our findings from evaluating existing HEP Physics middleware and application components, including GridFTP, Globus Online, etc. in the high-speed environment. These will include possible recommendations to the system administrators, application and middleware developers on changes that would make production use of the 100 Gb/s networks, including data storage, caching and wide area access.
15931690
Track extrapolation and distribution for the CDF-II trigger system
Abstract The CDF-II experiment is a multipurpose detector designed to study a wide range of processes observed in the high energy proton–antiproton collisions produced by the Fermilab Tevatron. With event rates greater than 1 MHz, the CDF-II trigger system is crucial for selecting interesting events for subsequent analysis. This document provides an overview of the Track Extrapolation System (XTRP), a component of the CDF-II trigger system. The XTRP is a fully digital system that is utilized in the track-based selection of high momentum lepton and heavy flavor signatures. The design of the XTRP system includes five different custom boards utilizing discrete and FPGA technology residing in a single VME crate. We describe the design, construction, commissioning and operation of this system.
199734
Mixed bino–wino–higgsino dark matter in gauge messenger models
Almost degenerate bino and wino masses at the weak scale constitute one of the unique features of gauge messenger models. The lightest neutralino is a mixture of bino, wino and higgsino and can produce the correct amount of dark matter density if it is the lightest supersymmetric particle. Furthermore, as a result of the squeezed spectrum of superpartners which is typical for gauge messenger models, various co-annihilation and resonance regions overlap and very often the correct amount of neutralino relic density is generated by an interplay of several processes. This feature makes the explanation of the observed amount of the dark matter density much less sensitive to fundamental parameters. We calculate the neutralino relic density assuming a thermal history and present both spin independent and spin dependent cross sections for direct detection. We also discuss phenomenological constraints from b → sγ and muon g−2 and compare results obtained using gauge messenger models to well known results for the mSUGRA scenario.
14201794
A new mechanism for baryogenesis living through electroweak era
Abstract We present a new mechanism for baryogenesis by introducing a heavy vector-like SU ( 2 ) W singlet quark(s) with Q em = 2 3 quark U or Q em = − 1 3 quark D . The lifetime of the heavy quark is assumed to be in the range 2 × 10 −11 s τ 1 s . Being SU ( 2 ) W singlet, it survives the electroweak phase transition era. It mixes with SU ( 2 ) W doublet quarks with tiny mixing angles to satisfy the FCNC constraints, where a simple Z 2 symmetry is suggested for realizing this scheme. The heavy quark asymmetry is generated in analogy with the old GUT scenario.
12889727
Criterion for admissible singularities in a brane world
When gravity couples to scalar fields in anti{endash}de Sitter (AdS) space, the geometry becomes non-AdS and develops singularities generally. We propose a criterion that the singularity is physically admissible if the integral of the on-shell Lagrangian density over the finite range is finite everywhere. For all classes of the singularities studied here, the criterion suggested in this paper coincides with an independent proposal made by Gubser that the potential should be bounded from above in the solution. This gives a reason why Gubser's conjecture works.
119293778
Neutrino assisted gauge mediation
Recent observation shows that the Higgs mass is at around 125 GeV while the prediction of the minimal supersymmetric standard model is below 120 GeV for stop mass lighter than 2 TeV unless the top squark has a maximal mixing. We consider the right-handed neutrino supermultiplets as messengers in addition to the usual gauge mediation to obtain sizeable trilinear soft parameters At needed for the maximal stop mixing. Neutrino messengers can explain the observed Higgs mass for stop mass around 1 TeV. Neutrino assistance can also generate charged lepton flavor violation including μ→eγ as a possible signature of the neutrino messengers. We consider the S4 discrete flavor model and show the relation of the charged lepton flavor violation, θ13 of neutrino oscillation and the muon’s g−2.