118433133
Millisecond dips in the 2007–09 RXTE/PCA light curve of Sco X-1 and one possible occultation event
Serendipitous stellar occultation search is so far the only way to detect the existence of very small, very dim, remote objects in the Solar system. To date, however, there are only very few reported detections for trans-Neptunian objects (TNOs) in optical bands. In the X-ray band, with the RXTE/PCA data of Sco X-1 taken from 2007 June to 2009 October, we found one possible X-ray occultation event. We discuss the veracity and properties of this event, and suggest upper limits to the size distribution of TNOs at hectometre size and of main-belt asteroids at decametre size.
118652654
Energy dependence of normal branch oscillations in Scorpius X-1
We report the energy dependence of normal branch oscillations (NBOs) in Scorpius X-1, a low-mass X-ray binary Z-source. Three characteristic quantities (centroid frequency, quality factor, and fractional root-mean-squared (rms) amplitude) of a quasi-periodic oscillation signal as functions of photon energy are investigated. We found that, although it is not yet statistically well established, there is a signature indicating that the NBO centroid frequency decreases with increasing photon energy when it is below 6− 8k eV, which turns out to be positively correlated with the photon energy at the higher energy side. In addition, the rms amplitude increases significantly with the photon energy below 13 keV and then decreases in the energy band of 13−20 keV. There is no clear dependence on photon energy for the quality factor. Based on these results, we suggest that the NBO originates mainly in the transition layer.
14722253
STATIC QUARK POTENTIAL AND THE RENORMALIZED ANISOTROPY ON TADPOLE IMPROVED ANISOTROPIC LATTICES
Static quark potential is studied using a tadpole improved gauge lattice action. The scale is set using the potential for a wide range of bare parameters. The renormalized anisotropy of the lattice is also measured.
27442116
Cold neutron energy dependent production of ultracold neutrons in solid deuterium.
A measurement of the production of ultracold neutrons from velocity-selected cold neutrons on gaseous and solid deuterium targets is reported. The expected energy dependence for two-particle collisions with well defined neutron and Maxwell-Boltzmann distributed molecular velocities is found for the gas target. The solid target data agree in shape with the phonon density-of-states curve and provide strong evidence for the phonon model including multiphonon excitations.
118375342
Supersymmetric extension of the minimal dark matter model
The minimal dark matter model is given a supersymmetric extension. A super SU(2)(L) quintuplet is introduced with its fermionic neutral component still being the dark matter, and the dark matter mass is about 19.7 TeV. Mass splitting among the quintplet due to supersymrnetry particles is found to be negligibly small compared to the electroweak corrections. Other properties of this supersymmetry model are studied, it has the solutions to the PAMELA and Fermi-LAT anomaly, and the predictions in higher energies need further experimental data to verify them.
5164847
Cyclic family symmetry and lepton hierarchy in supersymmetry
A cyclic symmetry among the left-handed doublets of the three families is proposed. This symmetry can naturally result in a realistic hierarchical pattern of the fermion masses within the framework of supersymmetry with nonvanishing sneutrino vacuum expectation values.
118639447
Pure gauge glueballs at finite temperature
Pure gauge glueballs at finite temperature are investigated in a large temperature range from 0:3Tc to 1:9Tc on anisotropic lattices. Optimized glueball operators are used to obtain better signals. It is found in all 20 symmetry channels that the pole masses MG of glueballs remain almost constants when the temperature approaches the critical temperature Tc from below, and start to reduce gradually with the temperature going above Tc. The glueball correlators in 0 ++ , 0 i+ , and 2 ++ channels, are also analyzed based on the Breit-Wigner ansatz by assuming a thermal width Γ to the pole mass ω0. While ω0's are insensitive to T in the whole temperature range, Γ's exhibit distinct behavior below and above Tc: They are only few percents of ω0 when T Tc and reach values of roughly Γ » ω0=2 at T … 1:9Tc.