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The Technical Design for the COMET Phase-I experiment is presented in this paper. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into electrons in the field of an aluminium nucleus ($\mu-e$ conversion, $\mu^- N \to e^- N$); a lepton flavor violating process. The experimental sensitivity goal for this process in the Phase-I experiment is $3.1\times10^{-15}$, or 90 % upper limit of branching ratio of $7\times 10^{-15}$, which is a factor of 100 improvement over the existing limit. The expected number of background events is 0.032. To achieve the target sensitivity and background level, the 3.2 kW 8 GeV proton beam from J-PARC will be used. Two types of detectors, CyDet and StrECAL, will be used for detecting the \mue conversion events, and for measuring the beam-related background events in view of the Phase-II experiment, respectively. Results from simulation on signal and background estimations are also described., Comment: A minor correction applied in Eq. 3

In quasi-two dimensional Ce(Ir,Rh)In$_5$ system, it has been suggested that the phase diagram contains two distinct domes with different heavy fermion superconducting states. We here report the systematic pressure dependence of the electron transport properties in the normal state of CeRh$_{0.2}$Ir$_{0.8}$In$_{5}$ and CeIrIn$_{5}$, which locates in first and second superconducting dome, respectively. We observed non-Fermi liquid behavior at low temperatures in both compounds, including non-quadratic $T-$dependence of the resistivity, large enhancement of the Hall coefficient, and the violation of the Kohler's rule in the magnetoresistance. We show that the cotangent of Hall angle $\cot \Theta_H$ varies as $T^2$, and the magnetoresistance is quite well scaled by the Hall angle as $\Delta \rho_{xx}/\rho_{xx}\propto \tan^2\Theta_H$. The observed transport anomalies are common features of Ce$M$In$_{5}$ ($M$=Co, Rh, and Ir) and high-$T_c$ cuprates, suggesting that the anomalous transport properties observed in CeIrIn$_{5}$ are mainly governed by the antiferromagnetic spin fluctuations, not by the Ce-valence fluctuations which has been proposed to be the possible origin for the second superconducting dome., Comment: 8 pages, 7 figures, To be published in Phys. Rev. B

Crab cavities have been installed in the KEKB B--Factory rings to compensate the crossing angle at the collision point and thus increase luminosity. The beam operation with crab crossing has been done since February 2007. This is the first experience with such cavities in colliders or storage rings. The crab cavities have been working without serious issues. While higher specific luminosity than the geometrical gain has been achieved, further study is necessary and under way to reach the prediction of simulation., Comment: Submitted to Particle Accelerator Conference 2007, MOZAKI01, Albuquerque

We present a systematic study of the dc-resistivity, Hall effect, and magnetoresistance in the normal state of quasi 2D heavy fermion superconductors CeMIn5 (M: Rh and Co) under pressure. Here the electronic system evolves with pressure from an antiferromagnetic (AF) metal, through a highly unconventional non-Fermi liquid, and finally into a Fermi-liquid state. The amplitude of the Hall coefficient increases dramatically with decreasing T, reaching at low temperatures a value significantly larger than 1/ne. Furthermore, the magnetoresistance is characterized by T- and H-dependence which clearly violate Kohler's rule. We found that the Hall angle cot\Theta varies as T^2, and the magnetoresistance is well scaled by the Hall angle as \Delta \rho_{xx}/\rho_{xx}\propto \tan^2\Theta. These non-Fermi liquid properties in the electron transport are remarkably pronounced when the AF fluctuations are enhanced in the vicinity of the QCP. We lay particular emphasis on the striking resemblance of these anomalous magnetotransport with those of the high-Tc cuprates. We argue that features commonly observed in quasi 2D heavy fermion and cuprates very likely capture universal features of strongly correlated electron systems., Comment: 16 pages, 15 figures

We have numerically explored the stable planetary geometry for the multiple systems involved in a 2:1 mean motion resonance, and herein we mainly study the HD 82943 system by employing two sets of the orbital parameters (Mayor et al. 2004; Ji et al. 2004). In the simulations, we find that all stable orbits are related to the 2:1 resonance that can help to remain the semi-major axes for two companions almost unaltered over the secular evolution for $10^{8}$ yr. In addition, we also show that there exist three possible stable configurations:(1) Type I, only $\theta_{1} \approx 0^{\circ}$, (2) Type II, $\theta_{1}\approx\theta_{2}\approx\theta_{3}\approx 0^{\circ}$ (aligned case), and (3) Type III, $\theta_{1}\approx 180^{\circ}$, $\theta_{2}\approx0^{\circ}$, $\theta_{3}\approx180^{\circ}$ (antialigned case), where two resonant arguments are $\theta_{1} = \lambda_{1} - 2\lambda _{2} + \varpi_{1}$ and $\theta_{2} = \lambda_{1} - 2\lambda_{2} + \varpi_{2}$, the relative apsidal longitudes $\theta_{3} = \varpi_{1}-\varpi_{2}=\Delta\varpi$. And we find that other 2:1 resonant systems (e.g., GJ 876) may possess one of three stable orbits in their realistic motions. Moreover, we also study the existence of the assumed terrestrial bodies at $\sim 1$ AU for HD 82943 and GJ 876 systems (see main texts)., Comment: 9 pages, 4 figures, submitted to Advances in Space Research, proceeding of COSPAR 2004, Paris

To date, more than 100 giant Jupiter-like planets have been discovered in Doppler surveys of solar-type stars. In this paper, we perform simulations to investigate three systems: GJ 876, HD 82943 and 55 Cnc. The former two systems both have a pair of planets in the 2:1 Mean Motion Resonance (MMR), while the inner two companions of the later is close to 3:1 MMR. By integrating hundreds of the planetary orbits of three systems for million years, we find that for GJ 876 and HD 82943, the critical argument $\lambda_{1} - 2\lambda_{2} + \varpi_{1}$ and $\lambda_{1} - 2\lambda_{2} + \varpi_{2}$ librate about $0^{\circ}$ or $180^{\circ}$, indicating 2:1 MMR can play an important role in stabilizing the motion of the planets so that they are protected from frequent close encounters. As for 55 Cnc, we further show the three resonant arguments for 3:1 MMR execute librations for millions of years respectively, which reveals the evidence of the resonance for this system. Additionally, we should emphasize another vital mechanism is the apsidal phase-locking between a couple of planets for a certain system. For GJ 876 and HD 82943, we discover the relative apsidal longitudes $\varpi_{1} - \varpi_{2}$ move about $0^{\circ}$ or $180^{\circ}$, respectively; but for 55 Cnc, we find that there exists an asymmetric apsidal libration between two inner planets. Finally, we made a brief discussion about the Habitable Zones in the exoplanetary systems., Comment: 5 pages, 3 figures and 1 table. In Proc. of IAU Symposium 219: Stars as Suns: Activity, Evolution, and Planets, eds. A. K. Dupree & A. Benz

(Abridged) We have numerically explored the stable planetary geometry for the multiple systems involved in a 2:1 mean motion resonance, and herein we mainly concentrate on the study of the HD 82943 system by employing two sets of the orbital parameters (Mayor et al. 2004). We find that all stable orbits are related to the 2:1 commensurability for $10^{7}$ yr, and the apsidal phase-locking between two orbits can further enhance the stability for this system. For HD 82943, there exist three possible stable configurations:(1) Type I, only $\theta_{1} \approx 0^{\circ}$,(2) Type II, $\theta_{1}\approx\theta_{2}\approx\theta_{3}\approx 0^{\circ}$ (aligned case), and (3) Type III, $\theta_{1}\approx 180^{\circ}$, $\theta_{2}\approx0^{\circ}$, $\theta_{3}\approx180^{\circ}$ (antialigned case), here the lowest eccentricity-type mean motion resonant arguments are $\theta_{1} = \lambda_{1} - 2\lambda_{2} + \varpi_{1}$ and $\theta_{2} = \lambda_{1} - 2\lambda_{2} + \varpi_{2}$, the relative apsidal longitudes $\theta_{3} = \varpi_{1}-\varpi_{2}=\Delta\varpi$. In addition, we also propose a semi-analytical model to study $e_{i}-\Delta\varpi$ Hamiltonian contours. With the updated fit, we examine the dependence of the stability of this system on the orbital parameters. Moreover, we numerically show that the assumed terrestrial bodies cannot survive near the habitable zones for HD 82943 and low-mass planets can be dynamically habitable in the GJ 876 system at $\sim 1$ AU in the numerical surveys., Comment: 45 pages, 10 figures, submitted to ApJ

We investigated the apsidal motion for the multi-planet systems. In the simulations, we found that the two planets of HD 37124, HD 12661, 47 Uma and HD 82943 separately undergo apsidal alignment or antialignment. But the companions of GJ 876 and $\upsilon$ And are only in apsidal lock about $0^{\circ}$. Moreover, we obtained the criteria with Laplace-Lagrange secular theory to discern whether a pair of planets for a certain system are in libration or circulation., Comment: 13 Pages, 3 figures, 2 tables, Published by ApJ Letters, 591, July 1, 2003 (Figures now included to match the publication)

We perform numerical simulations to explore the dynamical evolution of the HD 82943 planetary system. By simulating diverse planetary configurations, we find two mechanisms of stabilizing the system: the 2:1 mean motion resonance between the two planets can act as the first mechanism for all stable orbits. The second mechanism is a dynamical antialignment of the apsidal lines of the orbiting planets, which implies that the difference of the periastron longitudes $\theta_{3}$ librates about $180^{\circ}$ in the simulations. We also use a semi-analytical model to explain the numerical results for the system under study., Comment: 8 Pages, no figures, submitted to Celestial Mechanics and Dynamical Astronomy, Proceedings of IAU 189 Colloquium(Astrophysical Tides: Effects in the Solar and Exoplanetary Systems), Sept. 2002, Nanjing, P.R. China

We carry out numerical simulations to explore the dynamical evolution of the HD 82943 and HD 37124 planetary systems,which both have two Jupiter-like planets. By simulating various planetary configurations in the neighborhood of the fitting orbits, we find three mechanisms to maintain the stability of these systems: For HD 82943,we find that the 2:1 mean motion resonance can act as the first mechanism for all the stable orbits. The second mechanism is the alignment of the periastron of the two planets of HD 82943 system. In the paper,we show one case is simultaneously maintained by the two mechanisms. Additionally,we also use the corresponding analytical models successfully to explain the different numerical results for the system. The third mechanism is the Kozai resonance which takes place in the mutual highly orbits of HD 37124. In the simulations,we discover that the argument of periastron $\omega$ of the inner planet librates about $90^{\circ}$ or $270^{\circ}$ for the whole time span. The Kozai mechanism can explain the stable configuration of large eccentricity of the inner planet., Comment: 23 pages, submitted to ApJ; figures not included here. For figures, please contact the author directly via: jijh@pmo.ac.cn