Footprints of Supersymmetry on Higgs Decay

Motivated by future collider proposals that aim to measure the Higgs properties precisely, we study the partial decay widths of the lightest Higgs boson in the minimal supersymmetric standard model with an emphasis on the parameter region where all superparticles and heavy Higgs bosons are not accessible at the LHC. Taking account of phenomenological constraints such as the Higgs mass, flavor constraints, vacuum stability, and perturbativity of coupling constants up to the grand unification scale, we discuss how large the deviations of the partial decay widths from the standard model predictions can be. These constraints exclude large fraction of the parameter region where the Higgs widths show significant deviation from the standard model predictions. Nevertheless, even if superparticles and the heavy Higgses are out of the reach of 14TeV LHC, the deviation may be large enough to be observed at future $e^+e^-$ collider experiments.Comment: 24 pages, 8 figures, version accepted in JHE

On the Gauge Invariance of the Decay Rate of False Vacuum

We study the gauge invariance of the decay rate of the false vacuum for the model in which the scalar field responsible for the false vacuum decay has gauge quantum number. In order to calculate the decay rate, one should integrate out the field fluctuations around the classical path connecting the false and true vacua (i.e., so-called bounce). Concentrating on the case where the gauge symmetry is broken in the false vacuum, we show a systematic way to perform such an integration and present a manifestly gauge-invariant formula of the decay rate of the false vacuum.Comment: 17 pages, published versio

Renormalization-Scale Uncertainty in the Decay Rate of False Vacuum

We study radiative corrections to the decay rate of false vacua, paying particular attention to the renormalization-scale dependence of the decay rate. The decay rate exponentially depends on the bounce action. The bounce action itself is renormalization scale dependent. To make the decay rate scale-independent, radiative corrections, which are due to the field fluctuations around the bounce, have to be included. We show quantitatively that the inclusion of the fluctuations suppresses the scale dependence, and hence is important for the precise calculation of the decay rate. We also apply our analysis to a supersymmetric model and show that the radiative corrections are important for the Higgs-stau system with charge breaking minima.Comment: 15 pages, 2 figures; added reference

Alcoholic Liver Disease

Relationship between ethanol drinking and organs injury was reviewed and special emphasis was put on alcoholic liver disease. Consumption of alcoholic beverage expressed as ethanol per capita of adult in Japan increased 2.1 times in these 25 years and it is still increasing. Although the incidence of alcoholic liver disease in Japan also increased greatly during the above period, it seems likely that plateau level is coming because of genetically defined, unique type of alcohol metabolism in Japanese. Sex differences in susceptibility to alcohol were discussed. Among the six types of alcoholic liver disease, alcoholic liver fibrosis is relatively frequent in Japan. Mechanism of liver injury has been studied extensively. Alcohol itself is toxic but other factors such as dietary fat are also important. Biochemical and immunological markers of drinking were presented. As for the treatment, most patients especially in early stages of the disease well respond to alcohol withdrawal, but therapy of alcohol dependence in the background of the disease is very difficult requiring cooperative works of different kinds of specialists

A study on students' idears about the school syllabus

1995年4月に初めての本学のシラバス（講義要覧）が発行され、学生に配布された。本報は約1年後の1996年2月の試験期間中にシラバスに対する学生の意見を問うために行われたアンケート調査の結果をまとめたものである。回答を寄せた学生は435人で、在籍学生の89.0％であった。よく利用したとする学生は18.2％、数回利用したとする学生は67.6％であった。学生の使用目的はテストの準備や履修科目の決定のためであった。以上のことから、現在のシラバスは学生が日常的により活用するためにはさらに教師が改善、工夫する必要があると思われた。The first syllabus of the School was published and distributed to all of the students in April,1995. Ten months later during the term examination, an opportunity arouse to question the sudents about their idears for the syllubus. A survery of all of the students was carried out and 435 students (89.0%) responded to it. They generally utilized it well, especially to decide which subjects they will take, to find out about the textbooks that will be used, and how to prepare for the examination. However it was found not to be sufficient for their daily use. Teachers therefore must make a greater effort in giving information about their lecture

Automatic Dance Video Segmentation for Understanding Choreography

Segmenting dance video into short movements is a popular way to easily understand dance choreography. However, it is currently done manually and requires a significant amount of effort by experts. That is, even if many dance videos are available on social media (e.g., TikTok and YouTube), it remains difficult for people, especially novices, to casually watch short video segments to practice dance choreography. In this paper, we propose a method to automatically segment a dance video into each movement. Given a dance video as input, we first extract visual and audio features: the former is computed from the keypoints of the dancer in the video, and the latter is computed from the Mel spectrogram of the music in the video. Next, these features are passed to a Temporal Convolutional Network (TCN), and segmentation points are estimated by picking peaks of the network output. To build our training dataset, we annotate segmentation points to dance videos in the AIST Dance Video Database, which is a shared database containing original street dance videos with copyright-cleared dance music. The evaluation study shows that the proposed method (i.e., combining the visual and audio features) can estimate segmentation points with high accuracy. In addition, we developed an application to help dancers practice choreography using the proposed method.Comment: 9 pages, 11 figure

Curvaton mechanism and its implications to sneutrino cosmology

I describe basic features of the curvaton scenario where the primordial fluctuation of a late-decaying scalar field, called ``curvaton,'' becomes the dominant source of the cosmic density fluctuations. I also discuss its implications to sneutrino cosmology.Comment: 11 pages. Invited Talk at the Fujihara Seminar ``SEESAW 1979 - 2004: Neutrino Mass and Seesaw Mechanism'' (Feb 23 - 25, 2004, KEK, Japan). To be published in Nucl. Phys B (Proceedings Supplement

Curvatons in Supersymmetric Models

We study the curvaton scenario in supersymmetric framework paying particular attention to the fact that scalar fields are inevitably complex in supersymmetric theories. If there are more than one scalar fields associated with the curvaton mechanism, isocurvature (entropy) fluctuations between those fields in general arise, which may significantly affect the properties of the cosmic density fluctuations. We examine several candidates for the curvaton in the supersymmetric framework, such as moduli fields, Affleck-Dine field, $F$- and $D$-flat directions, and right-handed sneutrino. We estimate how the isocurvature fluctuations generated in each case affect the cosmic microwave background angular power spectrum. With the use of the recent observational result of the WMAP, stringent constraints on the models are derived and, in particular, it is seen that large fraction of the parameter space is excluded if the Affleck-Dine field plays the role of the curvaton field. Natural and well-motivated candidates of the curvaton are also listed.Comment: 34 pages, 5 figure

Evaluation of New Image Processing Conditions for Digital Mammograms from FUJI Computed Radiography

2006-06departmental bulletin pape