Studying 750 GeV Di-photon Resonance at Photon-Photon Collider

Motivated by the recent LHC discovery of the di-photon excess at the invariant mass of ~ 750 GeV, we study the prospect of investigating the scalar resonance at a future photon-photon collider. We show that, if the di-photon excess observed at the LHC is due to a new scalar boson coupled to the standard-model gauge bosons, such a scalar boson can be observed and studied at the photon-photon collider with the center-of-mass energy of ~ 1 TeV in large fraction of parameter space.Comment: 16 pages, 3 figures. v2:Fig.1 corrected, discussions and references added. v3: version published in PL

AN ANALYSIS OF PARTICIPIAL CONSTRUCTION AND ITS APPLICATION TO ENGLISH EDUCATION

This study analyzes participial construction and aims to give an answer to why conjunctions like “when” and “while” are used in some participial construction by considering the iconic principle of sequential order, which is explained in Radden and Dirven (2007). In order to consider why conjunctions are added to participial constructions, we collect examples from COCA and analyze the differences between preposed and postposed participle clauses. With the analysis, we can argue that the order of clauses plays a role in showing the ground. i.e., the ground can either be expressed by adding the conjunction while, or by putting the clauses that express the ground in front. On the other hand, in the case of the participle clause with the conjunction when, we could not see such differences in the position; the clause with when can either be preposed or postposed. This might be attributable to the fact that when clearly shows simultaneity. Also, through the analysis, we will propose a better teaching method for the Japanese EFL learners

Extending the LHC Reach for New Physics with Sub-Millimeter Displaced Vertices

Particles with a sub-millimeter decay length appear in many models of physics beyond the Standard Model. However, their longevity has been often ignored in their LHC searches and they have been regarded as promptly-decaying particles. In this letter, we show that, by requiring displaced vertices on top of the event selection criteria used in the ordinary search strategies for promptly-decaying particles, we can considerably extend the LHC reach for particles with a decay length of $\gtrsim 100~\mu{\rm m}$. We discuss a way of reconstructing sub-millimeter displaced vertices by exploiting the same technique used for the primary vertex reconstruction on the assumption that the metastable particles are always pair-produced and their decay products contain high-$p_{\rm T}$ jets. We show that, by applying a cut based on displaced vertices on top of standard kinematical cuts for the search of new particles, the LHC reach can be significantly extended if the decay length is $\gtrsim 100~\mu{\rm m}$. In addition, we may measure the lifetime of the target particle through the reconstruction of displaced vertices, which plays an important role in understanding the new physics behind the metastable particles.Comment: 18 pages, 6 figure

Detection of vitellogenin incorporation into zebrafish oocytes by FITC fluorescence

<p>Abstract</p> <p>Background</p> <p>Large volumes of lymph can be collected from the eye-sacs of bubble-eye goldfish. We attempted to induce vitellogenin (Vtg) in the eye-sac lymph of bubble-eye goldfish and develop a method for visualizing Vtg incorporation by zebrafish oocytes using FITC-labeling.</p> <p>Methods</p> <p>Estrogen efficiently induced Vtg in the eye-sac lymph of goldfish. After FITC-labeled Vtg was prepared, it was injected into mature female zebrafish.</p> <p>Results</p> <p>Incorporation of FITC-labeled Vtg by zebrafish oocytes was detected in <it>in vivo </it>and <it>in vitro </it>experiments. The embryos obtained from zebrafish females injected with FITC-labeled Vtg emitted FITC fluorescence from the yolk sac and developed normally.</p> <p>Conclusion</p> <p>This method for achieving Vtg incorporation by zebrafish oocytes could be useful in experiments related to the development and endocrinology of zebrafish oocytes.</p

Searching for Metastable Particles with Sub-Millimeter Displaced Vertices at Hadron Colliders

A variety of new-physics models predict metastable particles whose decay length is $\lesssim 1$ mm. Conventional displaced-vertex searches are less sensitive to this sub-millimeter decay range, and thus such metastable particles have been looked for only in usual prompt decay searches. In this paper, we show that an additional event-selection cut based on the vertex reconstruction using charged tracks considerably improves the sensitivity of ordinary searches which rely only on kinematic selection criteria, for particles with a decay length of $\gtrsim 100$ $\mu \text{m}$. To that end, we consider a metastable gluino as an example, and study the impact of this new event-selection cut on gluino searches at the LHC by simulating both the signal and Standard Model background processes. Uncertainty of the displaced-vertex reconstruction due to the limited resolution of track reconstruction is taken into account. We also discuss possibilities for optimization of the kinematic selection criteria, which takes advantage of significant reduction of background through the requirement of displaced vertices. In addition, we demonstrate that using the method discussed in this paper it is possible to measure the lifetime of metastable particles with an ${\cal O}(1)$ accuracy at the high-luminosity LHC. Implications for a future 100 TeV collider are also studied, where produced particles tend to be more boosted and thus it is easier to detect the longevity of metastable particles.Comment: 55 pages, 24 figure