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The mass and radius of neutron star (NS) in the low mass X-ray binary (LMXB) can be measured simultaneously from the evolving spectra of the photospheric radius expansion (PRE) X-ray bursts (XRBs). Precise measurements require the distance to the target, information on the radiating surface, and the composition of accreted material. Future observations with large groundbased telescopes such as Giant Magellan Telescope (GMT) and Thirty Meter Telescope (TMT) may reduce the uncertainties in the estimation of the mass and radius of NS because they could provide information on the composition of accreted material by identifying the companion stars in LMXBs. We investigate these possibilities and present our results for selected targets. [ABSTRACT FROM AUTHOR]

Neutron star provides unique environments for the investigation of the physics of extreme dense matter beyond normal nuclear saturation density. In such high density environments, hadrons with strange quarks are expected to play very important role in stabilizing the system. Kaons and hyperons are the lowest mass states with strangeness among meson and bayron families, respectively. In this work, we investigate the role of kaons and hyperons to the neutron star mass, and discuss their role in the neutron star cooling. [ABSTRACT FROM AUTHOR]

Neutron star (NS) is one of the most interesting astrophysical compact objects for hardronic physics. It is believed that the central density of NS can reach several times the normal nuclear matter density (ρ0). Hence, the inner part of NS is the ultimate testing place for the physics of dense matter. Recently, the mass of NS in a NS-white dwarf (WD) binary PSR J1614-2230 has been estimated to be 1.97 ± 0.04M☉[1]. Since this estimate is based on the observed Shapiro delay, it can give the lower limit of the maximum NS mass and rules out many soft equations of state. On the other hand, all the well-measured NS masses in NS-NS binaries are smaller than 1.5M☉. In this work, by introducing the supercritical accretion during the binary evolution, we propose a possibility of forming higher mass NS in NS-WD binaries. In this scenario, the lifetimes of NS and WD progenitors are significantly different, and NS in NS-WD binary can accrete > 0.5M☉ after NS formation during the giant phase of the progenitor of WD. On the other hand, for the binary system with NS and heavier (> 8M☉) giants, the first-born NS will accrete more from the companion and can collapse into black hole. The only way to avoid the supercritical accretion is that the initial masses of progenitors of NS binary should be very close so that they evolve almost at the same time and don't have time to accrete after NS formation. [ABSTRACT FROM AUTHOR]

Fast fault restoration is essential in carrier-grade transport network for QoS-guaranteed service provisioning and efficient traffic engineering. The performances of multi-layered protection switching with control-forwarding separation, however, have not been studied in detail. In this paper, we propose a fast fault restoration in multi-layered network with Control-Forwarding separation. The proposed scheme leverages the merits of each layer, such as fast fault detection in WDM Optical layer, traffic engineering in MPLS layer, and hierarchical priority-based resource sharing in IP layer. The performances of the proposed fast fault restoration with control-forwarding separation are analyzed with a series of systematic tests. From the experiments, we found that the fault restoration time in IP/MPLS network with control-forwarding separation is less than 10 msec in a network with 9 forwarding elements in 3 × 3 mesh topology, while it takes around 90ms in a network with 256 nodes (16 × 16) mesh network. These results show that the multi-layered network with control-forwarding separation has scalability for carrier-grade QoS-guaranteed service provisioning. [ABSTRACT FROM PUBLISHER]

Implementation of Cu interconnects into Silicon Integrated Circuits (IC’s) has been instrumental in the continuing improvement of IC device performance. Copper as a well known Gate Oxide Integrity (GOI) killer [1, 2] requires extensive protocols to minimize the possibility of cross contamination. Despite such protocols the risk for cross contamination exists, and consequently there is the need for in-line Cu cross-contamination detection metrology. Preferably the metrology will be non-destructive, fast, and capable of mapping on product wafers. Up to now the most common approaches for monitoring Cu contamination in IC fabrication lines either measure Cu in the bulk Si, which is not applicable to Cu cross-contamination monitoring because Back-End-of-the-Line thermal budgets restrict the ability to diffuse the surface Cu into the bulk Si; or the techniques are not optimal for in-line monitoring due to their destructive, time-consuming, or costly nature. In this work we demonstrate for the first time the application of the ac-Surface Photo Voltage (ac-SPV) surface lifetime approach [3] to in-line, full wafer coverage mapping of low level (<1E9 cm-2) surface Cu contamination. The low level sensitivity is achieved through integration of a novel preferential surface Cu activation procedure into a production ready metrology system. Furthermore, because the metrology is non-contact (utilizing edge-grip handling) and non-destructive, it is directly applicable to measurement of production wafers. In-line fab data acquired using this metrology is presented and compared to data from Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). [ABSTRACT FROM AUTHOR]