Search

The Super DIOS project, which is an improved version of DIOS (Diffuse Intergalactic Oxygen Surveyor), is one of the candidates for Japan's future scientific satellites, to be launched after 2030. The main scientific objective of the project is to unravel the flow of energy and metal cycles at various scales from galaxies, galaxy clusters to the warm-hot intergalactic medium along the Cosmic Web. The primary goal is the quantification of baryons, especially the unidentified "dark baryons". Super DIOS will have a wide field of view of ∼ 1 degree, with an angular resolution of ∼ 15 arcseconds and high energy resolution ( E / d E > 1000 ). The detector will be a 30 kilo-pixel array of Transition Edge sensor (TES) with a micro-wave SQUID multiplexer read-out system. In this paper, we report on the scientific concept of Super DIOS and the status of its newly developed technologies. [ABSTRACT FROM AUTHOR]

GHz LC resonators whose resonance frequency depends on temperature may be put to use as radiation detectors. We have demonstrated that a resonator utilizing STO (SrTiO $$_{3}$$ ) at 4 and 2 K detected infrared light emitting diode (LED) light, by a shift of resonance frequency around 2 GHz. A suitable design of a resonator array with temperature-dependent dielectric material will be used as a large-format microcalorimeter array without or with only very small Johnson noise. [ABSTRACT FROM AUTHOR]

Hydrothermal systems (viz. aqueous solution systems with high temperature (100-374°C) and pressure (0·1-22 MPa) are frequently acknowledged as multi-functional reaction media for various organic and inorganic reactions. This paper presents two typical uses of exhaust superheated steam for hydrothermal dehydration of bamboo and cedar leaves at moderate conditions (<300°C). The active carbon prepared by the dehydration of bamboo and cedar leaves was characterised by scanning electron microscope, Brunauer-Emmett-Teller (BET) method and adsorption behaviour of heavy metals (e.g. Pb and Cd). The results indicate that the as-prepared active carbon from bamboo had a higher absorption ability than the commercial activated carbon formed by heating biomass at 800°C. Moreover, the as-prepared carbon from cedar leaves expressed a much better adsorption of Pb than the commercial carbon products. Therefore, this demonstrates great potential of disposed exhaust stream up to 300°C in the uses of the hydration of the biomass to produce high-performance active carbon products. [ABSTRACT FROM AUTHOR]

Many experiments for visualizing quantized vortices and normal fluid flow have been performed in superfluid He. Recently, metastable He excimer molecules have been used as tracer particles. Since their radius is only about 10 m, they hardly perturb the system, thus being a good candidate of tracer particles. In order to understand the interactive motion of He molecules and vortices at zero temperature, we numerically study the trapping diameter by using the self-consistent equations of motions. We calculated the trapping diameter as a function of the initial velocity of the particle. The trapping diameter is almost inversely proportional to the initial velocity of the particle and compared with the observation. [ABSTRACT FROM AUTHOR]

We present the results from Suzaku observations of the Perseus Cluster, which is relatively close, the brightest in the X-ray sky, and a relaxed object with a cool core. A number of exposures of central regions and offset pointing with the X-ray Imaging Spectrometer cover a region within radii of 20′-30′. The central data are used to evaluate the instrumental energy-scale calibration with accuracy confirmed to within around 300 km s–1 by the spatial and temporal variation of the instruments. These deep and well-calibrated data are used to measure X-ray redshifts of the intracluster medium. A hint of gas bulk motion, with radial velocity of about –(150-300) km s–1 relative to the main system, was found at 2′-4′ (45-90 kpc) west of the cluster center, where an X-ray excess and a cold front were found previously. No other velocity structure was discovered. Over spatial scales of 50-100 kpc and within 200 kpc radii of the center, the gas-radial-velocity variation is below 300 km s–1, while over scales of 400 kpc within 600 kpc radii, the variation is below 600 km s–1. These X-ray redshift distributions are compared spatially with those of optical member galaxies for the first time in galaxy clusters. Based on X-ray line widths, gas turbulent velocities within these regions are also constrained within 1000-3000 km s–1. These results of gas dynamics in the core and larger scales in association with cluster merger activities are discussed, and the future potential of high-energy resolution spectroscopy with ASTRO-H is considered. [ABSTRACT FROM AUTHOR]

For future X-ray astronomy, a microcalorimeter array that has both mega-pixel imaging capability and eV-level high energy-resolution is desirable. In order to realize it, thermometers with negligible self-heating, multiplexing readout and close packing are essential components. We propose a novel detector concept, a dielectric microcalorimeter (DMC) and present current design studies. The DMC uses dielectric pixels as thermometers which form LC resonators in GHz band. The signals from many pixels can be easily multiplexed in a similar way to kinetic inductance detectors. The dielectric pixels are easy to be integrated into large and dense arrays. However, dielectrics with temperature-dependent permittivity below 2 K were not known. We evaluated quantum ferroelectric strontium titanate (STO) used in a capacitive thermometer higher than 2 K as a suitable dielectric for the DMC pixels. We fabricated STO capacitors and measured their capacitance from 2 K down to 80 mK. As a result, we found that their capacitive thermometer sensitivity at 100 mK are dlog C/ dlog T∼10, and they can be sensitive enough to detect X-ray with a resonator. We report the concepts, the measurement details, expected response to X-ray irradiation and our designs of the DMC. [ABSTRACT FROM AUTHOR]

E2A-hepatic leukemia factor (HLF) is a chimeric protein found in B-lineage acute lymphoblastic leukemia (ALL) with t(17;19). To analyze the leukemogenic process and to create model mice for t(17;19)-positive leukemia, we generated inducible knock-in (iKI) mice for E2A-HLF. Despite the induced expression of E2A-HLF in the hematopoietic tissues, no disease was developed during the long observation period, indicating that additional gene alterations are required to develop leukemia. To elucidate this process, E2A-HLF iKI and control littermates were subjected to retroviral insertional mutagenesis. Virus infection induced acute leukemias in E2A-HLF iKI mice with higher morbidity and mortality than in control mice. Inverse PCR detected three common integration sites specific for E2A-HLF iKI leukemic mice, which induced overexpression of zinc-finger transcription factors: growth factor independent 1 (Gfi1), zinc-finger protein subfamily 1A1 isoform a (Zfp1a1, also known as Ikaros) and zinc-finger protein 521 (Zfp521). Interestingly, tumors with Zfp521 integration exclusively showed B-lineage ALL, which corresponds to the phenotype of human t(17;19)-positive leukemia. In addition, ZNF521 (human counterpart of Zfp521) was found to be overexpressed in human leukemic cell lines harboring t(17;19). Moreover, both iKI for E2A-HLF and transgenic for Zfp521 mice frequently developed B-lineage ALL. These results indicate that a set of transcription factors promote leukemic transformation of E2A-HLF-expressing hematopoietic progenitors and suggest that aberrant expression of Zfp521/ZNF521 may be clinically relevant to t(17;19)-positive B-lineage ALL. [ABSTRACT FROM AUTHOR]

Chronic myelogenous leukemia (CML) is a hematopoietic disorder, which begins as indolent chronic phase but inevitably progresses to fatal blast crisis. p210BCR/ABL, a constitutively active tyrosine kinase, is responsible for disease initiation but molecular mechanism(s) underlying disease evolution remains largely unknown. To explore this process, we employed retroviral insertional mutagenesis to CML-exhibiting p210BCR/ABL transgenic mice (Tg). Virus infection induced acute lymphoblastic leukemia (ALL) in p210BCR/ABL Tg with a higher frequency and in a shorter latency than wild-type littermates, and inverse PCR detected two retrovirus common integration sites (CISs) in p210BCR/ABL Tg tumors. Interestingly, one CIS was the transgene itself, where retrovirus integrations induced upregulation of p210BCR/ABL and production of truncated BCR/ABL with an enhanced kinase activity. Another CIS was Notch1 gene, where retrovirus integrations resulted in overexpression of Notch1 and generation of Notch1 lacking the C-terminal region (Notch1ΔC) associated with stable expression of its activated product, C-terminal-truncated Notch intracellular domain (NICDΔC). In addition, generation of Tg for both p210BCR/ABL and Notch1ΔC developed ALL in a shortened period with Stat5 activation, demonstrating the cooperative oncogenicity of Notch1ΔC/NICDΔC with p210BCR/ABL involving Stat5-mediated pathway. These results demonstrated that overexpression/enhanced kinase activity of BCR/ABL and altered expression of Notch1 induces acute leukemia in a transgenic model for CML.Oncogene (2008) 27, 3465–3474; doi:10.1038/sj.onc.1211007; published online 14 January 2008 [ABSTRACT FROM AUTHOR]

In order to establish a sustainable society, with practical material recycling, it is appropriate to focus on a range of guiding “Earth Principles”, including the character and application of hydrothermal processes. In this paper, it is demonstrated that information obtained from the study of fundamental Earth Principles can be used to inspire the development of new methods for material recycling, such as the following: [ABSTRACT FROM AUTHOR]

This work focuses on interaction between granite–stainless steel (SUS) pipe–dry steam in the presence of Cu. Three types of hydrothermal experiments were conducted: (1) SUS–Cu–granite, (2) SUS–Cu, (3) SUS–granite. It was found that a high protective amorphous AlSi1,6O4 layer (thickness about 5 μm) was formed on the supporting pipe surface only in the case of SUS–Cu–granite interaction. The Al silicate layer formed during the experiment was characterized by X-ray diffraction (XRD) techniques and scanning electron microscopy (SEM) with EDX. According to kinetic data this layer has high protective properties. [Copyright &y& Elsevier]

Investigates the effect of copper on granite-dry steam interaction. Analysis of the surface of a copper table following granite-copper-dry steam interaction; Requirements for the formation of copper volatile compounds; Details on the activation role of copper in the release of aluminum from granite surface in dry steam.

Abstract: The optical properties of π-conjugated polymer films based on poly(p-phenylene vinylene) (PPV) units under a wet condition were studied. We succeeded in producing multimode laser emission under a wet condition from cylindrical microcavities with a polymer thin film fabricated onto the inner surface of an optical capillary tube, which was filled with cyclohexane. Furthermore, lasing spectral modulation was demonstrated with the polymer laser. We discuss the lasing spectral modulation by taking the change in refractive index into consideration. [Copyright &y& Elsevier]

Introduction/Background Falls are popular and major problem for stroke patient during their hospital stay. The aim of this study is to reveal the factors associated with the risk of fall in stroke inpatients. Material and method Retrospective study carried out with stroke hospitalized patients. Thirty-four stroke patients who fell and 34 stroke patients who did not fall during their hospital stay underwent structured medical examinations to identify factors associated with fall. The control subjects were matched for age, height, body weight, body mass index (BMI), and primary diagnosis. Potential variables related to fall risk factors were collected from medical records. A conditional logistic regression was performed to calculate odds ratios using SPSS. Clinical data were collected from January to December 2016. “An unexpected displacement of the body to a lower level than the initial position without loss of consciousness” was regarded as fall. Results Nutrition status, evaluated with modified CONUT score at admission, was significantly associated with fall risk (odds ratio = 3.11, 95% CI: 1.18–9.94). There were no statistically significant differences in the other candidate factors (e.g. sarcopenia, activities of daily living, and rehabilitation intervention) between the two groups. Conclusion Our findings demonstrated that nutrition status was associated with fall risk in stroke hospitalized patients. Further studies are needed to reveal that nutritional intervention can contribute to falls prevention in stroke patients. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the oral environment and the taste function of Japanese HIV-infected patients treated with antiretroviral therapy. Their median age of 73 patients taking anti-HIV drugs was 46 years. The median period of taking anti-HIV drugs was 30 months. The oral condition was evaluated by measurement of oral moisture, amount of saliva secretion, the number of oral bacteria, presence of oral candida, a taste test, and the number of missing teeth. The levels of oral moisture and secreted saliva were significantly lower in the HIV-infected group than in the healthy volunteer (control) group. The HIV-infected group showed a more robust decrease in taste sensation than the control group. The number of missing teeth was significantly higher in the HIV-infected group than in the control group. Furthermore, all of the evaluated oral conditions were worse in the HIV-infected patients whose CD4+ T lymphocyte counts were less than 500/mm3 than in the control group. It became clear that the patients taking anti-HIV drugs, especially the CD4+ count < 500/mm3 group, had a deteriorated oral environment and dysgeusia, suggesting that the management of oral hygiene is necessary to maintain oral health, which leads to systemic health. [ABSTRACT FROM AUTHOR]

We designed, fabricated, and measured anti-reflection coating (ARC) on sapphire that has 116% fractional bandwidth and transmission of at least 97% in the millimeter wave band. The ARC was based on patterning pyramid-like sub-wavelength structures (SWS) using ablation with a 15 W femto-second laser operating at 1030 nm. One side of each of two disks was fabricated with SWS that had a pitch of 0.54 mm and a height of 2 mm. The average ablation volume removal rate was 1.6 mm 3 /min. Measurements of the two-disk sandwich show transmission higher than 97% between 43 and 161 GHz. We characterize instrumental polarization (IP) arising from differential transmission due to asymmetric SWS. We find that with proper alignment of the two-disk sandwich, RMS IP across the band is predicted to be 0.07% at normal incidence and less than 0.6% at incidence angles up to 20 °. These results indicate that laser ablation of SWS on sapphire and on other hard materials such as alumina is an effective way to fabricate broadband ARC. [ABSTRACT FROM AUTHOR]

A 57 Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition if a hypothetical elementary particle, axion, exists to solve the strong CP problem. Transition edge sensor (TES) X-ray microcalorimeters can detect such axions very efficiently if they are again converted into photons by a 57 Fe absorber. We have designed and produced a dedicated TES array with 57 Fe absorbers for the solar axion search. The iron absorber is set next to the TES, keeping a certain distance to reduce the iron-magnetization effect on the spectroscopic performance. A gold thermal transfer strap connects them. A sample pixel irradiated from a 55 Fe source detected 698 pulses. In contrast to thermal simulations, we consider that the pulses include either events produced in an iron absorber or gold strap at a fraction dependent on the absorption rate of each material. Furthermore, photons deposited on the iron absorber are detected through the strap as intended. The identification of all events still needs to be completed. However, we successfully operated the TES with the unique design under iron magnetization for the first time. [ABSTRACT FROM AUTHOR]

We laser-ablated sub-wavelength structures (SWS) on 200 mm diameter birefringent sapphire disks to produce broadband anti-reflection coating (ARC). The disks were assembled into a stack of five plates making an achromatic half-wave plate (AHWP) suitable for operation between 40 and 140 GHz. We report on the SWS fabrication and transmission measurements of the stack at room temperature. From the measurements, we compute a band average transmission and modulation efficiency for nine spectral bands that correspond to the frequency coverage of the LiteBIRD Low-Frequency Telescope (LFT). We also assess the level of instrumental polarization the AHWP exhibits. We discuss paths for further development to minimize the instrumental polarization from the AHWP. This work is a development milestone toward the implementation of an AHWP for the LiteBIRD satellite. [ABSTRACT FROM AUTHOR]

This study attempted to develop detection methods for solar axions using transition-edge-sensor (TES) microcalorimeters. Since the axion absorber comprised of iron-57 (57Fe) is electroplated upon the membrane instead of directly onto the TES itself (with the absorber hence thermally connected to the TES via a gold thermal strap), some of the heat deposited into the absorber consequently escapes into the heat bath through the membrane before being detected by the TES. If the heat-loss depends upon the axion interaction position within the absorber, position dependence may degrade the energy resolution. Therefore, this study endeavored to evaluate the dependence of heat-loss and pulse shape on axion incident position with the COMSOL Multiphysics software package (using a finite element method). In addition, heat-loss and pulse shape were likewise evaluated when the energy was deposited directly within the gold thermal strap. [ABSTRACT FROM AUTHOR]

We developed an N 2 gas scintillation counter as a time-of-flight counter for particle identification of radioactive isotope beams. Radiation damage, which often becomes a problem for high-intensity heavy ion beams, can be prevented by a continuous flow of N 2 gas. The scintillator, with a volume of 60 mm × 60 mm × 100 mm, was filled with N 2 gas at a pressure of approximately 100 kPa. Photons were detected using photomultiplier tubes attached to both sides of the vessel. The main emission wavelength of photons produced in the detector was 300–400 nm. Performance tests confirmed that the detector had sufficient detection efficiency, intrinsic time resolution, and short decay time. Additionally, the detector was demonstrated to be effective for particle identification. [ABSTRACT FROM AUTHOR]

Abstract: Background: Lung transplantation cases have immunosuppression maintainedusing a calcineurin inhibitor, anti-metabolites, and steroid. Case Report: We report 2 clinical cases inwhich anti-metabolites (mycophenolate mofetil) were successfully withdrawn after livingdonor lobar lung transplantation by monitoring immune function using the ImmuKnow®assay. In the first case, a 43-year-old woman underwent living donor lobar lungtransplantation for pulmonary alveolar proteinosis. Two healthy relatives donated alower lobe each. Immunosuppression was maintained using tacrolimus, mycophenolatemofetil, and steroid. Six months posttransplantation, she developed invasivepulmonary aspergillosis. During anti-fungal treatment, we withdrew mycophenolate mofetiland tacrolimus trough levels were kept around 8 ng/mL. Despite the resultinglow-level immunosuppression, the ImmuKnow assay showed immune function to bein the moderate range with tacrolimus and steroid alone, encouraging us tomaintain this strategy to avoid recurrence of invasive pulmonary aspergillosis. In thesecond case, a 24-year-old man underwent living donor lobar lung transplantation forcystic fibrosis. Two healthy relatives donated a lower lobe each. Immunosuppressionwas maintained using tacrolimus, mycophenolate mofetil, and steroid. Five monthsposttransplantation, he developed persistent Pseudomonas aeruginosa pneumonia derivedfrom the paranasal sinuses. Under ImmuKnow assay monitoring, mycophenolate mofetilwas withdrawn, but immune function was maintained within the moderate range usingtacrolimus and steroid alone. Discussion: Respiratory function in both cases was maintained; nofindings of bronchiolitis obliterans syndrome were noted during this period. To the bestof our knowledge, no reports have described successful anti-metabolite withdrawal inlung transplantation with ImmuKnow monitoring. Immune evaluation by ImmuKnowcould offer a useful method to monitor and control immune status, particularly amongrecipients susceptible to infection, revealing that moderate immune function could bemaintained using tacrolimus and steroid in living donor lobar lung transplantation. [Copyright &y& Elsevier]

We have been improving our TEM-EDS for elemental microanalysis after a successful achievement of a high energy resolution (7.8 eV at 1.7 keV) using a TES microcalorimeter. The improvements fall into a 3D superconductive wiring and a high-speed processing (∼3,000 cps). We are implementing a 10-ch TES array for higher count rate and a broader dynamic range. The shape of a probe needs to be a small polygonal rod with an approximate size of 1 cm×1 cm×10 cm, and hence the placing and wiring of the TES array and read-out circuits at the cryogenic stage were very demanding. We overcame those difficulties by 3D photolithography and electrodeposition. With these new technologies, we developed the OFC probe with solder-plated 3D wiring, and successfully observed a superconductivity at the temperature of liquid helium. As a required count rate per channel is ∼300 cps, the overall system count rate is ∼3,000 cps, which is incomparably higher than before. In the last model, we used an embedded system to process waveforms from a 4-ch 14-bit 1 MS/s ADC due to a small signal bandwidth, but this time we parallelized three identical ADCs and transfer raw waveforms by Ethernet lines to a host to achieve the required system count rate. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The purpose of this study was to assess the kinematic and kinetic effects of wearing a laterally wedged insole on the knee joint moment during gait, specifically in the frontal plane, in normal healthy adults. DESIGN: Motion analyses were conducted with (1) a three-dimensional motion analysis system and (2) ground reaction force analysis using force platforms when subjects walked under three different insole conditions: no wedge, a low wedge with a 3-degree lateral angle, and a high wedge with a 6-degree lateral angle. RESULTS: The high-wedge insole significantly reduced the knee joint varus moment during gait compared with the gait with the no-wedge insole. The actual segment angles at the subtalar and knee joints did not show any changes due to insole conditions. In contrast, the subtalar joint valgus moment increased for the high-wedge insole. This finding was correlated with a greater moment arm of the subtalar joint valgus moment with the high-wedge insole. CONCLUSIONS: These results indicate that, under dynamic conditions, the subjects wearing laterally wedged insoles had both changes of moments at the subtalar and knee joints via the more laterally shifted location of the center of pressure. [ABSTRACT FROM AUTHOR]

We report very-low-noise, fast-response, middle-scale multiplexing in a microwave superconducting quantum interference device multiplexer (MW-Mux) as a transition-edge sensor (TES) readout. Our MW-Mux is able to read 40 channels with 500 kHz sampling and has a low readout noise of 0.9 μ Φ 0 / Hz (where Φ 0 is the magnetic flux quantum), equivalent to 9 pA / Hz. By contrast, a multiplexer of less than 10 pixels with 500 kHz sampling and ∼ 2 μ Φ 0 / Hz readout noise has so far been reported in the literature. Owing to the 500 kHz sampling, our MW-Mux exhibits a fast response to detect a TES pulse with a rise time around 12 μ s. We demonstrated simultaneous readout of 38 pixels from an array of x-ray TES microcalorimeters. The measured full-width values at half-maximum spectral resolution ranged from 2.79 to 4.56 eV, with a median value of 3.30 eV at 5.9 keV, including a ∼ 10 % contribution of readout noise, i.e., 0.9–1.7 eV. [ABSTRACT FROM AUTHOR]

We have developed a four-pixel array of superconducting transition-edge sensors with gold absorbers for the detection of a 29.2 keV γ -ray doublet decay from 229 Th. To identify the decay, an energy resolution better than 20 eV full width at half maximum (FWHM) is needed. We measured an energy resolution of 14 eV FWHM for 26 keV γ -ray decay from an 241 Am isotope in combined data of three pixels. We describe the design and the performance of the devices and discuss the baseline correction method to compensate the variation in the baseline, which was observed during the evaluation of the performance using the 241 Am isotope. [ABSTRACT FROM AUTHOR]

Several issues in developing transition edge sensor (TES) microcalorimeters for the search of monochromatic solar axions expected at 14.4 keV are studied. The potential problem of developing TES's of this purpose is in that an axion absorber of 57 Fe must be placed in close vicinity of a TES. We estimated the minimum distance to avoid magnetic interference from iron using magnetic FEM simulations, and found it 30 μ m for an iron of 5 μ m thickness. We fabricated a TES with a 10 μ m thick iron membrane separated by 60 μ m. We confirmed the superconducting transition for this TES. However, both the residual normal resistance and the transition temperature was different from those of TES without iron. We also estimated the low-temperature thermal conductivity of an iron membrane by measuring the low-temperature electrical resistance and by applying the Wiedemann–Franz law. We estimated the pulse-shape dependency on the interaction position within the 57 Fe converted using thermal FEM simulations. We found that the pulse-shape variations will limit the energy resolution to about 30 eV FWHM. [ABSTRACT FROM AUTHOR]

A dielectric capacitance thermometer was fabricated using KTa 0.99 Nb 0.01 O 3 (KTN) quantum ferroelectric material for assembling a prototype of the dielectric microcalorimeter (DMC). The prototype of the DMC was assembled with the KTN thermometer and irradiated with alpha rays with an energy of 5.5 MeV with applying a constant bias voltage at a temperature of 100 mK. For recording detection signal pulses, the trigger signals were generated by shaping output of a preamplifier using a band-pass filter with a pass frequency of 1–10 kHz. [ABSTRACT FROM AUTHOR]

The updated program of the future Japanese X-ray satellite mission Diffuse Intergalactic Oxygen Surveyor (DIOS), called as Super DIOS, is planned to search for dark baryons in the form of warm-hot intergalactic medium (WHIM) with high-resolution X-ray spectroscopy. The mission will detect redshifted emission lines from OVII, OVIII and other ions, leading to an overall understanding of the physical nature and spatial distribution of dark baryons as a function of cosmological timescale. We have started the conceptual design of the satellite and onboard instruments, focusing on the era of 2030s. The major change will be an improved angular resolution of the X-ray telescope. Super DIOS will have a 10-arcsec resolution, which is an improvement by a factor of about 20 over DIOS. With this resolution, most of the contaminating X-ray sources will be separated, and the level of the diffuse X-ray background will be much reduced after subtraction of point sources. This will give us higher sensitivity to map out the WHIM in emission. [ABSTRACT FROM AUTHOR]

The X-ray Astronomy Recovery Mission (XARM) is a recovery mission of ASTRO-H/Hitomi, which is expected to be launched in Japanese Fiscal Year of 2020 at the earliest. The Resolve instrument on XARM consists of an array of 6 × 6 silicon-thermistor microcalorimeters cooled down to 50 mK and a high-throughput X-ray mirror assembly with the focal length of 5.6 m. Hitomi was launched into orbit in February 2016 and observed several celestial objects, although the operation of Hitomi was terminated in April 2016. The soft X-ray spectrometer (SXS) on Hitomi demonstrated high-resolution X-ray spectroscopy of ~ 5 eV FWHM in orbit for most of the pixels. The Resolve instrument is planned to mostly be a copy of the Hitomi SXS and soft X-ray telescope designs, though several changes are planned based on the lessons learned from Hitomi. We report a brief summary of the SXS performance and the status of the Resolve instrument. [ABSTRACT FROM AUTHOR]

We have first demonstrated the cooperation between an X-ray TES and a directly coupled microwave SQUID multiplexer (D-coup. MW-Mux) in which SQUIDs are directly coupled to resonators. Using D-coup. MW-Mux, we successfully detected the X-ray pulses from a single-pixel TES and evaluated the energy resolution of 11.8 eV FWHM at 5.9 keV. We found this preliminary energy resolution is attributed to non-optimum bias point of the present TES, which can be improved by the future reduction of readout noise. [ABSTRACT FROM AUTHOR]

We present the latest update and progress on the future Japanese X-ray satellite mission Diffuse Intergalactic Oxygen Surveyor (DIOS). DIOS is proposed to JAXA as a small satellite mission, and would be launched with an Epsilon rocket. DIOS would carry on the legacy of ASTRO-H, which carries semiconductor-based microcalorimeters and is scheduled to be launched in 2016, in high-resolution X-ray spectroscopy. A 400-pixel array of transition-edge sensors (TESs) would be employed, so DIOS would also provide valuable lessons for the next ESA X-ray mission ATHENA on TES operation and cryogen-free cooling in space. We have been sophisticating the entire design of the satellite to meet the requirement for the Epsilon payload for the next call. The primary goal of the mission is to search for warm-hot intergalactic medium with high-resolution X-ray spectroscopy by detecting redshifted emission lines from OVII and OVIII ions. The results would have significant impacts on our understanding of the nature of 'dark baryons,' their total amount and spatial distribution, as well as their evolution over cosmological timescales. [ABSTRACT FROM AUTHOR]

We discuss the design and performance of a transition edge sensor (TES) X-ray microcalorimeter array for scanning transmission electron microscope (STEM)-energy dispersive X-ray spectroscopy (EDS). The TES X-ray microcalorimeter has better energy resolution compared to conventional silicon drift detector and STEM-EDS utilizing a TES detector makes it possible to map the distribution of elements on a specimen in addition to analyze the composition. The requirement for a TES detector is a high counting rate ( $$>$$ 20 kcps), wide energy band (0.5-15 keV) and good energy resolution ( $$<$$ 10 eV) full width at half maximum. The major improvement of this development is to increase the maximum counting rate. In order to accommodate the high counting rate, we adopted an $$8 \times 8$$ format, 64-pixel array and common biasing scheme for the readout method. We did all design and fabrication of the device in house. With the device we have fabricated most recently, the pulse decay time is 40 $$\upmu $$ s which is expected to achieve 50 kcps. For a single pixel, the measured energy resolution was 7.8 eV at 5.9 keV. This device satisfies the requirements of counting rate and energy resolution, although several issues remain where the performance must be confirmed. [ABSTRACT FROM AUTHOR]

A transition edge sensor (TES) microcalorimeter array as an X-ray sensor for a scanning transmission electron microscope system is being developed. The technical challenge of this system is a high count rate of $$\sim $$ 5000 counts/second/array. We adopted a 64 pixel array with a parallel readout. Common SQUID bias, and common TES bias are planned to reduce the number of wires and the resources of a room temperature circuit. The reduction rate of wires is 44 % when a 64 pixel array is read out by a common bias of 8 channels. The possible degradation of the energy resolution has been investigated by simulations and experiments. The bias fluctuation effects of a series connection are less than those of a parallel connection. Simple calculations expect that the fluctuations of the common SQUID bias and common TES bias in a series connection are $$10^{-7}$$ and $$10^{-3}$$ , respectively. We constructed 8 SQUIDs which are connected to 8 TES outputs and a room temperature circuit for common bias readout and evaluated experimentally. Our simulation of crosstalk indicates that at an X-ray event rate of 500 cps/pixel, crosstalk will broaden a monochromatic line by about 0.01 %, or about 1.5 eV at 15 keV. Thus, our design goal of 10 eV energy resolution across the 0.5-15 keV band should be achievable. [ABSTRACT FROM AUTHOR]

We are developing the frequency-division multiplexing (FDM) readout system aimed to realize the 400-pixel transition edge sensor (TES) microcalorimeter array for the DIOS mission as well as large-format arrays with more than a thousand of TES for future space missions such as the ATHENA mission. The developed system consists of the low-power superconducting quantum interference device (SQUID), the digital FDM electronics, and the analog front-end to bridge the SQUID and the digital electronics. Using the developed readout system, we performed a TES readout experiment and succeeded to multiplex four TES signals with the single-staged cryogenic setup. We have experienced two issues during the experiment: an excess noise and crosstalk. The brief overview of the developed system and the details, results, and issues of the TES multiplexing readout experiment is discussed. [ABSTRACT FROM AUTHOR]

We report the fabrication and evaluation of the Cu/Bi bilayer absorber with electrodeposition. We designed the Cu/Bi absorber to satisfy the requirements for scanning transmission electron microscope (STEM). The residual resistivity ratios of films of Cu and Bi with electrodeposition was $${5.91\pm 0.49}$$ and $${2.06\pm 0.33}$$ , respectively; these values are sufficient for the requirements of STEM. We found that the Cu/Bi bilayer absorber TES microcalorimeter experienced a pulse-shape variation and we considered that these variations were caused by the quality of the contact surface between the absorber and TES. In addition, we examined the structure of the absorber using focus ion beam analysis and STEM. The results suggest that an oxidation between the Cu and seed layer, in which the layer is an electrode for electrodeposition, yielded variations. Moreover, thermal simulation suggests that the thermal conduction between the absorber and TES caused variations. The results of this study will improve the process of Bi electrodeposition. [ABSTRACT FROM AUTHOR]

The dielectric micro calorimeter (DMC) is a novel radiation detector utilizing a GHz resonator with dielectric thermometer (Sekiya et al. in J Low Temp Phys 167:435, ). The advantage of using a DMC is that the detection mechanism is based on a phonon mediation without Johnson noise and quasi-particle decay process. A large format array of DMCs can be easily multiplexed by a resonator circuit in the readout at GHz band width. We describe the design of a DMC as an X-ray photon counter. It is optimized to detect photon at 5.9 keV energy. We consider $$^{18}$$ O-doped SrTiO $$_3$$ (STO18) and Nb-doped KTa $$_{(1-x)}$$ Nb $$_{x}$$ O $$_{3}$$ (KTN) as a candidate of dielectric thermometer. Dielectric materials which have sensitivity $$\alpha $$ (= d $$\log {C_{\mathrm {el}}}/d\log {T}$$ ) are also ideal for our application. We check that both STO18 and KTN have $$\alpha {\sim } 10^{3}$$ at 100 mK. If we assume a DMC resonator operating at 100 mK, we need a Q value of a resonator to be 2000 for X-ray detection. [ABSTRACT FROM AUTHOR]

A compact dry He- He dilution refrigerator (DR) was developed for operation of a superconducting transition edge sensor (TES) microcalorimeter x-ray detector mounted on a transmission electron microscope. A Gifford-McMahon (GM)-type mechanical cryocooler was used as a DR pre-cooler to operate the TES microcalorimeter without consuming liquid helium. To reduce the noise and vibrations generated by the GM cryocooler, the DR was separated from the cryocooler in a split system that allows a remote helium cooling loop to pre-cool the DR. In the DR unit, the dilution components of the still, the heat exchangers, and the cascade pair of mixing chambers were assembled into a compact cylinder. A snout made from an oxygen-free copper rod was attached to the DR mixing chamber for placement of the TES microcalorimeter x-ray detector. The lowest temperature and the cooling power in the mixing chamber were measured to be 87 mK and 20 μW at 100 mK, respectively. The DR unit was shown to maintain the temperature on top of the snout such that it was below the temperature required for multi-pixel-array TES microcalorimeter x-ray detector operation. [ABSTRACT FROM AUTHOR]

Frequency division multiplexing (FDM) is a promising approach to read out a large format transition-edge sensor (TES) array for future astrophysical missions. We constructed a four channel FDM readout system using baseband feedback in the MHz band. We demonstrated the principle of our FDM method with an actual TES array, a multiplexing SQUID and LC band-pass filters under 100 mK. The resonant frequencies of LC filters were consistent with the design value with an accuracy of better than 3 %. We successfully obtained X-ray pulses from two TESs simultaneously but the energy resolution was degraded to about 100 eV at 5.9 keV and crosstalk effects were observed. The origin of the crosstalk effects is investigated by modified setups. Based on comparative experiments and numerical calculations, we conclude that the non-linearity of the SQUID is the cause of some of the crosstalk effects. Unlike the regular crosstalk effect from the adjoining channels, the crosstalk effect due to non-linearity observed in this paper occurs in all channels. Solving these problems will help us to obtain FDM readout with sufficient energy resolution. [ABSTRACT FROM AUTHOR]