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Accepted: 2007-03-01, 資料番号: SA1000174000

A table-based technique for estimating single-event transient pulses is evaluated in the most crucial case for bulk MOSFET technologies where an ion penetrates the drain region. A device model of a bulk MOSFET is built in a 2-D numerical device simulation framework, and heavy-ion-induced transient currents flowing through its drain terminal are calculated. From the currents, single-event transient voltage pulses in an inverter are estimated with the table-based estimation technique. The results are compared with ones simulated in the mixed mode with the same device model and circuit configuration. The estimated pulses are comparable to the results in the mixed-mode device simulations. Moreover, the estimation accuracy can be improved by using a drain-capacitance compensation technique. An extrapolation technique based on the drain-voltage dependency of heavy-ion-induced transient currents is also presented to reduce the experimental costs for modeling.

The Fine Pixel CCD (FPCCD) is one of the candidate vertex detectors for the ILC. We performed neutron irradiation test of the FPCCD with CYRIC proton beam line at Tohoku University. After the irradiation of 19-year neutron fluence at the 500 GeV high luminosity ILC, the performance of the FPCCD was tested. The dark current increased but was still three order of magnitude smaller than signal charge. The fraction of hot pixels increased to 1.2 × 10−5 which is enough small for operation. Charge transfer inefficiencies for horizontal and vertical directions were measured to be 3.49 × 10−5 and 6.34 × 10−5, respectively. Even for the farthest pixel from a readout channel, 63% of signal remains after the transfer. We conclude that neutron fluence at the 500 GeV high luminosity ILC is not a problem for the FPCCD.

The muon anomalous magnetic moment (g-2) and the muon electric dipole moment (EDM) are the fundamental quantities in particle physics. The previous measurement in BNL (E821) achieved an accuracy of 0.54 ppm for g-2, and there is 3.3σ discrepancy between experimental value and the Standard Model prediction. And the present muon EDM limit is 1.8×10 e・cm. So we plan a new muon g-2/EDM measurement at J-PARC to measure the muon g-2 with the precision a 0.1 ppm and EDM with the sensitivity of 10 e・cm. In this experiment, we accelerate muon to 300 MeV/c, storage in the 3 T precision magnetic fields and reconstruct a track of muon decay positron by highly-segmented tracking detector. We use silicon strip sensors for the tracker because the tracker requires high rate capability, high stability against a large rate change, stable operation in a high magnetic field, and high position resolution. We optimized sensor specification and estimated the requirement of accuracy of the alignment by using the simulation. Based on the specifications, we produced two types of new test sensors. We evaluated the performance of test sensor, and estimated signal to noise ratio. We will present results of specification, estimation of the requirements for the sensor alignment, and test sensors evaluation. References [1] G.W. Bennett et al., Phys. Rev. D 73, 072003 (2006). [2] N. Saito et al., AIP Conf. Proc. 73 (2012) 45 z

Kota Kasahara∗, Shin-Hong Kim, Yuji Takeuchi, Ren Senzaki, Kazuki Nagata, Takuya Okudaira, Masahiro Kanamaru, Tatsuya Ichimura, Koya Moriuchi, Kenji Kiuchi, Yasuo Arai1, Masashi Hazumi1, Hirokazu Ikeda2, Shuji Matsuura2, Takehiko Wada2, Satoru Mima3, Hirokazu Ishino4, Takuo Yoshida5, Yukihiro Kato6, Erik Ramberg7, Mark Kozlovsky7, Paul Ruvinov7, Dmitri Segratskov7 University of Tsukuba, Ibaraki 305-8571, Japan 1KEK, Ibaraki 305-0801, Japan 2JAXA ISAS, Kanagawa 252-5210, Japan 3RIKEN, Saitama 351-0198, Japan 4Okayama University, Okayama 700-8530, Japan 5University of Fukui, Fukui 910-8507, Japan 6Kinki University, Osaka 577-8502, Japan 7Fermi National Accelerator Laboratory, Illinois, 60510, US E-mail: kasahara@hep.px.tsukuba.ac.jp

The application of a deep sub-micron CMOS process is rapidly being proliferated under a multi-chip project service through the joint efforts of related universities and research organizations. In order to compensate for the shortage in designer resources, circuit libraries of sub-micron CMOS processes have been organized to be used by amateur designers. In practice, the libraries are employed in several projects, and, thus, the libraries themselves gradually become more sophisticated to the extent of even being utilized for very recent fabrication processes such as a deep sub-micron FD-SOI CMOS process. A test circuit for the SOI CMOS process is designed and submitted to examine its performance and usefulness in a front-end analog circuit of radiation detectors.

The flow structure on the sand bars, containing both sub-critical flow and super-critical one, was examined by laboratory experiments and numerical analyses, focusing on the effects of riverbank roughness and riverbed topography. It was shown that the riverbank roughness decelerates the flow along riverbank, which accelerates the flow of the central part of the channel. Then, the flow is super-critical in the center part of the channel and is sub-critical near the riverbank, which was correctly predicted by the numerical analysis. Numerical simulation also clarified that the position of maximum velocity changes downward as the plane angle of sand bar front becomes large. It was suggested that the influence of riverbed must also be taken into consideration in the case of bank revetment.

We are developing analog ASICs for Cadmium Telluride (CdTe) pixel and line sensors for high energy astrophysics and other applications. In the ASIC development, we are cooperating with other application users to build up a library of "tried-and-true" circuit modules tuned for several processes ("Open IP project"). As an initial trial, a 2-dimensional ASIC with a pixel size of 260 /spl mu/m /spl times/ 260 /spl mu/m and a 1-dimensional ASIC with an improved analog circuit, both based on 0.35-/spl mu/m CMOS technology, were developed and investigated. The readout system of the pixel ASIC worked properly, but the electric/electronic noise was too large compared with our final goals of 1keV (FWHM). With the latter ASIC, we have preliminarily obtained an energy resolution of 4.9 keV (FWHM) for 59.5 keV gamma-rays combined with a Schottky CdTe diode detector.

It is important for river management to consider natural characteristics of the river. The upper reach of the KNU-river is characterized by the steep bed slope and the large channel width with sand bars. The purpose of this study is to analyze the flow that contains both sub-critical flow and super-critical flow on the sand bars numerically by using SIMPLE method. It is shown that the flow has super-critical area when the rate of discharge becomes small as for the obtained findings, and the water surface is found wavy in the super-critical area. The sub-critical flow and the super-critical flow are formed at the area of the downstream left side of slanting slope termination. The superficial hydraulic jump position is found in the central part of slanting slope termination.

The river landform or the riverbed form is very complicated and a change like 3-D is often shown. Moreover, recently, to grasp the replying of the riverbed form to the flow of the river that changes in the time is looked for. Therefore, in this research, it tried the construction of the system that measures a riverbed form in case of indoors experiment from the stereophotograph. Concretely, it the photograph took the situation of the riverbed (the pattern of sand) first with the stereo using the digital camera. It fixed compatible of the identical point during image by the correlation analysis of two images. It applied the technique of the analysis photogrammetry to the result and it calculated 3-D coordinates on the riverbed. Then, it changed a photography condition and it compared between the calculation result and the actual measurement result by the system.

Hepatic sinusoidal obstructive syndrome (HSOS) is a lifethreatening syndrome characterized by painful liver enlargement, weight gain, and jaundice, and generally occurs as a complication of hematopoietic stem cell transplantation (HSCT) [1] and chemotherapy in Wilm’s tumor [2]. HSOS after conventional chemotherapy for malignant disease other than Wilm’s tumor is unusual. Here, we report the first case to our knowledge of a 9-yearold boy with PCNSL who developed fatal HSOS during induction therapy. A 9-year-old boy presented with a 4-month history of hyperphagia. He was admitted to our department because of headache. The patient’s body weight was 40 kg (28 % obesity compared to ideal body weight). He had gained 15 kg in body weight over the previous 4 months. A physical examination revealed left-sided hemiparesis with a decreased mental status. The Eastern Cooperative Oncology Group performance status (ECOG-PS) was 3. Laboratory and coagulation tests showed the following: AST, 20 U/L; ALT, 21 U/L; LDH, 384 IU/L; total bilirubin, 0.3 mg/dl; activated partial thromboplastin time (aPTT), 33.2 s (normal 26–36 s); prothrombin time (PT), 10.8 s (normal 10–15 s), prothrombin time in international normalized ratio (PT-INR), 1.05 (normal 0.9–1.1); AT III activity level, 115 % (normal 80–120 %). Magnetic resonance imaging of the brain showed a mass with a homogeneous enhancement located in the right frontal lobe, and this lesion reached the hypothalamus (Fig. 1a). As the leftsided hemiparesis progressed rapidly, a sub-total excision of the tumor was performed. A pathological examination of the surgical specimen revealed a monotonous population of small-sized mononuclear lymphoblastic cells (Fig. 1b). Flow cytometry analysis revealed that lymphoblasts expressed TdT, cytoplasmic CD79a, CD10, and HLA-DR, leading to the diagnosis of precursor B-cell lymphoblastic lymphoma of the right cerebral hemisphere. A bone marrow examination revealed 6 % lymphoblasts. Cerebrospinal fluid (CSF) revealed 81 cells/mm leukocytes, with 82 % lymphoblasts. He showed no evidence of immunodeficiency, and a serological test for HIV was negative. Although optimal treatment of PCNSL in children has not yet been established, the effectiveness of combination chemotherapy for lymphoblastic lymphoma has been studied [3, 4]. We decided to treat the patient according to the protocol of pediatric advanced lymphoblastic lymphoma (ALBNHL03). An induction therapy regimen based on prednisone (60 mg/m daily for 5 weeks), vincristine (VCR) (1.5 mg/m on days 8, 15, 22, and 29), cyclophosphamide (1.0 g/m on day 8), daunorubicin (40 mg/m on days 8, 15, and 22), L-asparaginase (6,000 U/m on days 9, 11, 13, 16, 18, 20, 23, 25, and 27), and triple intrathecal therapy (methotrexate, cytarabine, and hydrocortisone, 12.5, 25, and 25 mg, respectively, on days 1, 15, and 29) (Fig. 2). Although he had shown rapid-onset obesity, no dose modification was made. His left-sided hemiparesis did not change; however, his mental status improved, and CSF tumor cells became negative on day 15. On day 27 of induction therapy, he developed peripheral neuropathy with pain. We stopped the induction therapy other than prednisone thereafter. However, the total bilirubin level was elevated to 2.1 mg/dl, with massive abdominal effusion and pain in the right upper quadrant on day 29. S. Yamamoto (&) K. Akiyama N. Oyama M. Hayashi Y. Fujimoto H. Ikeda K. Isoyama Division of Pediatrics, Department of Showa University Fujigaoka Hospital, 1-30 Fujigaoka Aoba-ku, Yokohama 227-8501, Japan e-mail: shohei-y@med.showa-u.ac.jp

Stem cell factor (SCF) has crucial roles in proliferation, survival, and differentiation of hematopoietic stem cells and mast cells through binding to c-Kit receptor (KIT). Chemotaxis is another unique function of SCF. However, little is known about the intracellular signaling pathway of SCF/KIT-mediated cell migration. To investigate the signaling cascade, we made a series of 22 KIT mutants, in which tyrosine (Y) residue was substituted for phenylalanine (F) in the cytoplasmic domain, and introduced into BAF3 cells or 293T cells. On stimulation with SCF, BAF3 expressing KITWT(WT) showed cell migration and Ca2+ mobilization. Among 22 YF mutants, Y567F, Y569F, and Y719F showed significantly reduced cell migration and Ca2+ mobilization compared to WT. In Y567F, Lyn activation on SCF stimulation decreased and C-terminal Src kinase (Csk) suppressed KIT-mediated Ca2+ influx and cell migration, suggesting that Y567-mediated Src family kinase (SFK) activation leads to Ca2+ influx and migration. Furthermore, we found that p38 mitogen-activated protein kinase (p38 MAPK) and Erk1/2 were also regulated by Y567/SFK and involved in cell migration, and that p38 MAPK induced Ca2+ influx, thereby leading to Erk1/2 activation. In Y719F, the binding of phosphatidylinositol 3′-kinase (PI3K) to KIT was lost and KIT-mediated cell migration and Ca2+ mobilization were suppressed by PI3K chemical inhibitors or dominant-negative PI3K, suggesting the involvement of Y719-mediated PI3K pathway in cell migration. Combination of Csk and the PI3K inhibitor synergistically reduced cell migration, suggesting the cooperation of SFK and PI3K. Taken together, these results indicate that 2 major KIT signaling pathways lead to cell migration, one is Y567-SFK-p38 MAPK-Ca2+ influx-Erk and the other is Y719-PI3K-Ca2+ influx.

We present a measurement of the branching fraction for the semileptonic B decay B 0 →D + l − ν , where l− can be either an electron or a muon. We find Γ( B 0 →D + l − ν )=(13.79±0.76±2.51) ns −1 , and the resulting branching fraction B ( B 0 →D + l − ν )=(2.13±0.12±0.39)% , where the first error is statistical and the second systematic. We also investigate the B 0 →D + l − ν form factor and the implications of the result for |Vcb|. From a fit to the differential decay distribution we obtain the rate normalization |Vcb|FD(1)=(4.11±0.44±0.52)×10−2. Using a theoretical calculation of FD(1), the Cabibbo–Kobayashi–Maskawa matrix element |Vcb|=(4.19±0.45±0.53±0.30)×10−2 is obtained, where the last error comes from the theoretical uncertainty of FD(1). The results are based on a data sample of 10.2fb−1 recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e+e− collider.

The BELLE detector for experiments at KEKB, a high luminosity, energy asymmetric B-factory, is now being constructed at KEK. An overview of the detector systems and their status is presented.

Recently, a number of methods have been devised for detection of mutations in the field of molecular genetics. The LightCycler system has been used for rapid PCR, while simultaneously quantifying and analyzing the amplification results. We tried to apply the LightCycler system to detect APRT*J allele mutations in two families including two children with 2,8-dihydroxyadenine urolithiasis. The first patient was a 3-year-old girl who presented with left flank pain. The second patient was a 2-year-old girl who presented with complaints of sudden dysuria. The spectrophotometric analysis of the stone fragments of both patients revealed an absorption spectrum for 2,8-DHA. We used the LightCycler system to detect APRT*J mutation. The first patient was homozygous for APRT*J/APRT*J and the second patient was compound heterozygous for APRT*J/APRT*Q0. The genetic diagnosis of APRT deficiency using this system may be useful not only as a diagnostic test for infants with known 2,8-DHA, but also as a screening of infants with a suspicion of urolithiasis. We believed that the LightCycler system still is an important means of identifying APRT*J mutation.

WF-MAXI is a mission to detect and localize X-ray transients with short-term variability as gravitational-wave (GW) candidates including gamma-ray bursts, supernovae etc. We are planning on starting observations by WF-MAXI to be ready for the initial operation of the next generation GW telescopes (e.g., KAGRA, Advanced LIGO etc.). WF-MAXI consists of two main instruments, Soft X-ray Large Solid Angle Camera (SLC) and Hard X-ray Monitor (HXM) which totally cover 0.7 keV to 1 MeV band. HXM is a multi-channel array of crystal scintillators coupled with APDs observing photons in the hard X-ray band with an effective area of above 100 cm 2 . We have developed an analog application specific integrated circuit (ASIC) dedicated for the readout of 32-channel APDs' signals using 0.35 μm CMOS technology based on Open IP project and an analog amplifier was designed to achieve a low-noise readout. The developed ASIC showed a low-noise performance of 2080 e - + 2.3 e - /pF at root mean square and with a reverse-type APD coupled to a Ce:GAGG crystal a good FWHM energy resolution of 6.9% for 662 keV -rays.

We present a proposal of an experiment for search for cosmic background neutrino decay. Due to the mass difference between neutrino generations, a heavier neutrino can decay into a lighter neutrino with a photon. Standard model predicts the neutrino lifetime is 10 44 year, while the current experimental lower limit of neutrino lifetime is 3 x10 12 year. However Left-Right symmetric model suggests much shorter neutrino lifetime down to 10 17 year in the shortest. If we assume a mass of the heaviest neutrino is 50 meV/c 2 , the expected photon energy at the neutrino rest frame is 25 meV. The energy spectrum of the photon from the cosmic background neutrino decay has a cutoff at this energy and a low energy tail due to a red shift effect as shown in Fig.1. Thus we propose an experiment to search for the photon emission from the decay of cosmic background neutrino by measuring the photon energy spectrum in the far infrared region with a superconducting tunneling junction (STJ) detector. We plan to perform a rocket experiment with the STJ detector in 2016 in the earliest, aiming at improving the neutrino lifetime limit by two order. We also aim at a 10-hour satellite experiment with 5 sensitivity for the neutrino lifetime of 10 17 year in further future [1]. [1] S. H. Kim, K. Takemasa, Y. Takeuchi and S. Matsuura, J. Phys. Soc. Jpn., 81 (2012) 024101S.

Conditional sampling method was adapted to clarify the three 3-D structure in periodical large vortices at the boundary between a river flow and vegetation zone along the river has a strong upward flow. It was shown that an upward flow and downward flow occur at the both edges of the free shear layer and main flow zone, and their intensity amounts to 80% of the turbulence intensity lateral velocity component.

Laboratory experiments were performed to examine flow pattern and oxygen supply by using a micro bubble aeration device in two-layered (densimetrically and anoxically) stratification. The flow pattern is different from two types confirmed previously. This was confirmed from vertical density and DO distributions. Micro bubbles have influenced on the flow pattern. Oxygen supply by using this device consists of gas exchange of micro bubbles and supply of oxygen saturation liquid. The efficiency of oxygen supply with this device that it used this time is twice airation system generating. Oxygen supply through micro bubbles is influenced from changing of height of density surface, increase of DO in the lower layer.

The concept of FPCCD (Fine Pixel CCD) whose pixel size is 5 × 5 μ m 2 has been proposed as vertex detector at ILC. Since FPCCD has 128 ×20,000 pixels in one readout channel, its readout poses a considerable challenge. We have developed a prototype of readout ASIC to readout the large number of pixels during the inter-train gap of the ILC beam. In this paper, we report the design and performance of the readout ASIC.

The pair monitor extracts information on the beam profile at the interaction point of the International Linear Collider. It utilizes the electron and positron number density distribution in the plane perpendicular to the beam direction. The pairs of electrons and positrons are detected by pixel detectors placed close to the beam on both sides of the interaction point, and a readout ASIC that meets the stringent requirements has been developed. In order to measure the beam profile as a function of location within a train and to deal with the high hit rate, the pixel detector is read out in 16 time-slices per bunch train. We develop the prototype ASIC using a 0.2 μ m fully depleted SOI (FD-SOI) CMOS process (OKI Semiconductor Co., Ltd). In this paper, we describe the design of the readout circuit and present the results of the performance tests.

A charge-to-amplitude converter (QAC) has been developed using the technology of a bipolar full-custom integrated circuit (IC). The newly developed QAC has two channels with different sensitivities: a high-sensitivity QAC channel and a wide dynamic range QAC channel. The sensitivities of both QAC channels are different by a factor of four. The input current signal is converted into a voltage amplitude within the gate signal width. The output voltages of the QAC are directly proportional to the input current signal. The QAC employs a current splitter at the input stage to meet a requirement for a wide dynamic-range conversion scheme. Both QAC channels with different sensitivities have achieved a non-linearity of 0.1% (10-bit-equivalent). The equivalent dynamic range can be realized to be 13 bits.

Field survey was carried out in order to clarify such important ecological aspects of trees in Kinu-Rivar as appropriate felling of trees, tree planting, and management of trees. In this study, investigation was made as to realities of growth condition of trees, secular changes and characteristics of tree environment by differences in cannel characteristics, and hydraulic conditions.And the following results were obtained as relations between the stages of growth speed of trees and dominant species, the direction of spread of trees, the effect of bed material characteristics, and the effect of inundation.

In Watarase Reservoir, a eutrophic shallow lake, fish kill phenomenon has been occurred especially during spring and summer. In this study, the dominant factor of this fish kill was investigated not only from ecological view point but also from that of water quality and movement. It was shown that the primary production of phytoplankton in this reservoir is high enough to feed fishes whose standing crop is high. Field observation with fish finder indicated that almost fishes exist in deep area near the bed. And it was concluded the sudden fall of dissolved oxygen at night, which is caused by stirring mud with strong wind, is one of the important factor of fish kill.

Yosasa-river of northern Totigi located eastern part of Japan suffered the biggest flood disaster by the strong rain fall, August 26, 1998. The natural bank of Yosasa-river has special characteristics for lateral erosion, and therefore, such peerless phenomena occurred, that floodwater seriously broke down the river banks and the width of channel became three to five times as wide as the original width. Moreover, some new channels were formed. On these occasions many sands, gravels and trees were yielded and flowed out.In this paper, some characteristics of channel changes and their causes in Yosasa-river were discussed basing on the results of field survey.

Comparative experiments were performed to examine generation factor of three dimensional structure in periodical large vortices at the boundary between a river flow and vegetation zone along the river. The first comparative experiment showed that the existence of the large vortices itself is most dominant factor rather than the effect of vegetation. The second one indicates that the important mechanism lies in the movement over the depth, not in the turbulence near the bed. And measurement of velocity fluctuations revealed that a strong upward flow is generated slightly behind the center of the vortex.

著者人数：20名, 資料番号: SA1000871000

著者人数：33名, 資料番号: SA1001500000

The c- kit receptor tyrosine kinase (KIT) is constitutively activated by naturally occurring mutations in either the juxtamembrane domain or the kinase domain. Although the juxtamembrane domain mutations led to ligand-independent KIT dimerization, the kinase domain mutations (Asp 814 → Val or Tyr) did not. In an effort to determine if the kinase domain mutant could transfer oncogenic signaling without receptor dimerization, we have constructed the truncated types of c- kit Wild and c- kit Tyr814 cDNAs (c- kit Del-Wild and c- kit Del-Tyr814 cDNAs, respectively), in which ligand-binding and ligand-induced dimerization domains were deleted. When c- kit Del-Wild and c- kit Del-Tyr814 genes were introduced into a murine interleukin-3 (IL-3)–dependent cell line Ba/F3, KIT Del-Tyr814 was constitutively phosphorylated on tyrosine and activated, whereas KIT Del-Wild was not. In addition, Ba/F3 cells expressing KIT Del-Tyr814 (Ba/F3 Del-Tyr814 ) grew in suspension culture without the addition of exogenous growth factor, whereas Ba/F3 cells expressing KIT Del-Wild (Ba/F3 Del-Wild ) required IL-3 for growth. The factor-independent growth of Ba/F3 Del-Tyr814 cells was virtually abrogated by coexpression of KIT W42 that is a dominant-negative form of KIT, but not by that of KIT Wild , suggesting that KIT Del-Tyr814 may not function as a monomer but may require receptor dimerization for inducing factor-independent growth. Furthermore, KIT Del-Tyr814 was found to be coimmunoprecipitated with KIT Wild or KIT W42 by an ACK2 monoclonal antibody directed against the extracellular domain of KIT. Moreover, KIT W42 was constitutively associated with a chimeric FMS/KIT Tyr814 receptor containing the ligand-binding and receptor dimerization domain of c- fms receptor (FMS) fused to the transmembrane and cytoplasmic domain of KIT Tyr814 , but not with a chimeric FMS/KIT Wild receptor even after stimulation with FMS-ligand. These results suggest that constitutively activating mutation of c- kit at the Asp 814 codon may cause a conformation change that leads to receptor self-association not in the extracellular domain and that the receptor self-association of the Asp 814 mutant may be important for activation of downstream effectors that are required for factor-independent growth and tumorigenicity.

A very compact solar neutron detector is made by using scintillation fiber and multi-anode photomultipliers. Signals from the 512 channels of the photomultipliers are read-out by CMOS circuitry which has been developed for a KEK B-factory experiment. The circuitry consumes only 5 W of power. The energy resolution for protons is obtained by exposing the detector to the RIKEN accelerator beam and it turns out to be 4.1% for protons at 95 MeV. The sensor will be used for observations on solar neutrons to elucidate the ion acceleration mechanism at the solar surface and also to provide information on-line to the cosmonauts about the impending arrival of strong radiations from the Sun.

Fragmentation of liquid metal takes place as basic processes of vapor explosions. This leads to rapid evaporation on the stretched interface. To date, a number of models explaining the fragmentation mechanisms have been proposed. However, few evidence has been obtained from the experiment because the phenomena are rapid. In Moving Particle Semi-implicit (MPS) method, grids are not necessary so that fluid fragmentation as well as multi-fluid thermal hydraulics can be analyzed. A numerical model of evaporation is developed for the present study. Impingement of water jets on a liquid metal pool is analyzed using the MPS method to investigate two typical models explaining the fragmentation mechanisms : Kim-Corradini and Ciccarelli-Frost models. Penetration of the water jet, which is assumed in Kim-Corradini model, is not observed in the calculation results. A filament of the liquid metal is observed between two water jets as assumed in Ciccarelli-Frost model. The filament appears when the jet density is smaller than the pool density, while the penetration appears when the jet density is hypotheticaly larger. The usual combinations of densities in vapor explosions are in the region of Ciccarelli-Frost model.

We explored wide-pitch ohmic-side structures for the BELLE SVD, where we proposed a field-plate structure combined with narrow p-barriers in between the readout electrodes of 90, 113, 180, and 226 μm-pitch detectors. The effect of the p-barriers was studied with a numerical model to trace the carrier trajectories. The charge collection and sharing properties were examined in practice for prototype small-size detectors with an IR pulse shining from either the junction side or the ohmic side. The channel separation capabilities were also shown to be appropriate under nominal operation conditions.

Employing a 64-channel CMOS preamplifier array, SMA2SH - 64 A, we studied its signal-to-noise ratio. Single-channel noise was substantially contaminated with a base-line shift, which was common for all neighboring channels. Subtracting the common base-line shift, we found that the noise level decreased to be acceptable in terms of the design parameters as well as for practical use.