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The CALorimetric Electron Telescope (CALET) on the International Space Station (ISS) consists of a high-energy cosmic ray CALorimeter (CAL) and a lower-energy CALET Gamma ray Burst Monitor (CGBM). CAL is sensitive to electrons up to 20 TeV, cosmic ray nuclei from Z = 1 through Z $\sim$ 40, and gamma rays over the range 1 GeV - 10 TeV. CGBM observes gamma rays from 7 keV to 20 MeV. The combined CAL-CGBM instrument has conducted a search for gamma ray bursts (GRBs) since Oct. 2015. We report here on the results of a search for X-ray/gamma ray counterparts to gravitational wave events reported during the LIGO/Virgo observing run O3. No events have been detected that pass all acceptance criteria. We describe the components, performance, and triggering algorithms of the CGBM - the two Hard X-ray Monitors (HXM) consisting of LaBr$_{3}$(Ce) scintillators sensitive to 7 keV to 1 MeV gamma rays and a Soft Gamma ray Monitor (SGM) BGO scintillator sensitive to 40 keV to 20 MeV - and the high-energy CAL consisting of a CHarge-Detection module (CHD), IMaging Calorimeter (IMC), and fully active Total Absorption Calorimeter (TASC). The analysis procedure is described and upper limits to the time-averaged fluxes are presented., 27 pages, 10 figures. Accepted for publication in ApJ

We present the measurement of the energy dependence of the boron flux in cosmic rays and its ratio to the carbon flux in an energy interval from 8.4 GeV/n to 3.8 TeV/n based on the data collected by the Calorimetric Electron Telescope (CALET) during ∼6.4 yr of operation on the International Space Station. An update of the energy spectrum of carbon is also presented with an increase in statistics over our previous measurement. The observed boron flux shows a spectral hardening at the same transition energy E_{0}∼200 GeV/n of the C spectrum, though B and C fluxes have different energy dependences. The spectral index of the B spectrum is found to be γ=-3.047±0.024 in the interval 25E200 GeV/n. The B spectrum hardens by Δγ_{B}=0.25±0.12, while the best fit value for the spectral variation of C is Δγ_{C}=0.19±0.03. The B/C flux ratio is compatible with a hardening of 0.09±0.05, though a single power-law energy dependence cannot be ruled out given the current statistical uncertainties. A break in the B/C ratio energy dependence would support the recent AMS-02 observations that secondary cosmic rays exhibit a stronger hardening than primary ones. We also perform a fit to the B/C ratio with a leaky-box model of the cosmic-ray propagation in the Galaxy in order to probe a possible residual value λ_{0} of the mean escape path length λ at high energy. We find that our B/C data are compatible with a nonzero value of λ_{0}, which can be interpreted as the column density of matter that cosmic rays cross within the acceleration region.

The ISS-based Calorimetric Electron Telescope (CALET) is directly measuring the energy spec- trum of electron+positron cosmic rays up to 20 TeV. Cosmic-ray electrons of TeV region energy are limited by energy loss to a propagation range of about 1 kpc, therefore the expected sources are a few nearby supernova remnants (SNR), with the Vela SNR dominating the spectrum. The latest spectrum measured by CALET in combination with the positron-only flux published by AMS-02 is fitted with a comprehensive model including nearby pulsars as the source of the positron excess. This model is extended to the TeV region by addition of the flux from the Vela SNR as calculated with DRAGON, with the integrated energy emitted in electron cosmic rays by the SNR as a variable scale factor. Exploring various scenarios for the time and energy dependence of the cosmic-ray release from Vela, under varied propagation conditions, best-fitting interpretations of the spectrum and upper limits on the emission of cosmic-ray electrons by Vela have been derived.

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV/n to 2.0 TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV/n to 2 TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.

We demonstrate that global observations of high-energy cosmic rays contribute to understanding unique characteristics of a large-scale magnetic flux rope causing a magnetic storm in August 2018. Following a weak interplanetary shock on 25 August 2018, a magnetic flux rope caused an unexpectedly large geomagnetic storm. It is likely that this event became geoeffective because the flux rope was accompanied by a corotating interaction region and compressed by high-speed solar wind following the flux rope. In fact, a Forbush decrease was observed in cosmic-ray data inside the flux rope as expected, and a significant cosmic-ray density increase exceeding the unmodulated level before the shock was also observed near the trailing edge of the flux rope. The cosmic-ray density increase can be interpreted in terms of the adiabatic heating of cosmic rays near the trailing edge of the flux rope, as the corotating interaction region prevents free expansion of the flux rope and results in the compression near the trailing edge. A northeast-directed spatial gradient in the cosmic-ray density was also derived during the cosmic-ray density increase, suggesting that the center of the heating near the trailing edge is located northeast of Earth. This is one of the best examples demonstrating that the observation of high-energy cosmic rays provides us with information that can only be derived from the cosmic ray measurements to observationally constrain the three-dimensional macroscopic picture of the interaction between coronal mass ejections and the ambient solar wind, which is essential for prediction of large magnetic storms., Comment: 19 pages, 3 figures, accepted for publication in the Space Weather

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV$/n$ to 2.0 TeV$/n$ allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number $Z$ = 40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV$/n$ to 2 TeV$/n$ our present data are compatible with a single power law with spectral index -2.60 $\pm$ 0.03., Comment: main text: 7 pages, 4 figures; supplemental material: 10 pages, 12 figures, 1 table. arXiv admin note: text overlap with arXiv:2012.10319

In this paper, we present the measurement of the energy spectra of carbon and oxygen in cosmic rays based on observations with the Calorimetric Electron Telescope (CALET) on the International Space Station from October 2015 to October 2019. Analysis, including the detailed assessment of systematic uncertainties, and results are reported. The energy spectra are measured in kinetic energy per nucleon from 10 GeV$/n$ to 2.2 TeV$/n$ with an all-calorimetric instrument with a total thickness corresponding to 1.3 nuclear interaction length. The observed carbon and oxygen fluxes show a spectral index change of $\sim$0.15 around 200 GeV$/n$ established with a significance $>3\sigma$. They have the same energy dependence with a constant C/O flux ratio $0.911\pm 0.006$ above 25 GeV$/n$. The spectral hardening is consistent with that measured by AMS-02, but the absolute normalization of the flux is about 27% lower, though in agreement with observations from previous experiments including the PAMELA spectrometer and the calorimetric balloon-borne experiment CREAM.

Background Myositis-specific autoantibodies (MSAs) are associated with unique clinical subsets in polymyositis/dermatomyositis (PM/DM). Autoantibodies against transcriptional intermediary factor (TIF)-1γ and TIF-1α are known to be MSAs. Previously, we reported that TIF-1β is also targeted in patients with DM with or without concomitant anti-TIF-1α/γ antibodies. Objectives To evaluate the clinical features of seven cases with anti-TIF-1β antibodies alone. Methods Serum autoantibody profiles were determined, and protein and RNA immunoprecipitation studies were conducted. Western blotting was performed to confirm autoantibody reactivity against TIF-1β. Results Anti-TIF-1β antibody was identified by immunoprecipitation assay in 24 cases. Among them, seven patients were positive for anti-TIF-1β antibody alone. Six of the seven patients were classified as having DM. Among the six cases of DM, two patients had no muscle weakness and normal creatine kinase (CK) levels, and were classified as having clinically amyopathic DM. Four patients had muscle weakness, but three of them had normal serum CK levels that responded well to systemic steroids. Characteristic features of DM included skin rashes, such as Gottron sign, periungual erythema, punctate haemorrhage on the perionychium and facial erythema including heliotrope, which were observed in 86%, 57%, 86% and 71% of our cases, respectively. One of the seven patients had appendiceal cancer. None of the patients had interstitial lung disease. Conclusions Seven patients were confirmed to have anti-TIF-1β antibody without any other MSAs, including TIF-1α/γ antibodies, and six of them were diagnosed with DM. We suggest that anti-TIF-1β antibody is an MSA, and that it is associated with clinically amyopathic DM or DM with mild myopathy.

The CALorimetric Electron Telescope (CALET) space experiment, which has been developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission on the International Space Station (ISS). The primary goals of the CALET mission include investigation of possible nearby sources of high-energy electrons, detailed study of galactic cosmic-ray acceleration and propagation, and search for dark matter signatures. With a long-term observation onboard the ISS, the CALET experiment measures the flux of cosmic-ray electrons (including positrons) up to 20 TeV, gamma-rays to 10 TeV, and nuclei up to 1,000 TeV based on its charge separation capability from Z = 1 to 40. Since the start of science operation in mid-October, 2015, a continuous observation has been maintained without any major interruptions. The number of triggered events over 10 GeV is nearly 20 million per month. By using the data obtained during the first two-years, here we present a summary of the CALET observations: 1) Electron+positron energy spectrum, 2) Nuclei analysis, 3) Gamma-ray observation with a characterization of the on-orbit performance. The search results for the electromagnetic counterparts of LIGO/Virgo gravitational wave events are also discussed.

著者人数: CALET Collaboration 100名 (所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 国城; 西村, 純; 高柳, 昌弘; 冨田, 洋; 上野, 史郎), Number of authors: 100 (Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS): Ebisawa, Ken; Fuke, Hideyuki; Mori, Kunishiro; Nishimura, Jun; Takayanagi, Masahiro; Tomida, Hiroshi; Ueno, Shiro), 資料番号: SA1190040000

The CALorimetric Electron Telescope (CALET) is an astroparticle physics experiment installed on the International Space Station since August 2015. The CALET mission was conceived to address several outstanding questions of high-energy astroparticle physics, like indirect detection of dark matter, the origin of cosmic rays (CRs), their mechanisms of acceleration and galactic propagation, the presence of possible nearby astrophysical CR sources. That can be achieved by precise measurements of the fluxes of CR electrons and γ rays up to the unexplored region above 1 TeV, and the energy spectra and composition of CR nuclei from a few tens of GeV to hundreds of TeV. In order to perform these observations, the instrument combines a thick total absorption PWO crystal calorimeter for energy measurement, a scintillator hodoscope for charge identification and thin imaging tungsten-scintillating fiber calorimeter providing accurate particle tracking and complementary charge measurement. In this paper, we will present an overview of the main CALET results based on the data collected in the first three years of the mission.

A new quantum gray-scale image watermarking scheme by using simple and small-scale quantum circuits is proposed. The NEQR representation for quantum images is used. The image sizes for carrier and watermark are assumed to be $$2n \times 2n$$2n×2n and $$n \times n$$n×n, respectively. At first, a classical watermark with $$n \times n$$n×n image size and 8 bits gray scale is expanded to an image with $$2n \times 2n$$2n×2n image size and 2 bits gray scale. Then the expanded image is scrambled to be a meaningless image by the SWAP gates that controlled by the keys only known to the operator. The scrambled image is embedded into the carrier image by the CNOT gates (XOR operation). The watermark is extracted from the watermarked image by applying operations in the reverse order. Simulation-based experimental results show that our proposed scheme is excellent in terms of three items, visual quality, robustness performance under noises, and computational complexity.

Unconventional superconductivity and magnetism are intertwined on a microscopic level in a wide class of materials. A new approach to this most fundamental and hotly debated issue focuses on the role of interactions between superconducting electrons and bosonic fluctuations at the interface between adjacent layers in heterostructures. Here we fabricate hybrid superlattices consisting of alternating atomic layers of heavy-fermion superconductor CeCoIn$_5$ and antiferromagnetic (AFM) metal CeRhIn$_5$, in which the AFM order can be suppressed by applying pressure. We find that the superconducting and AFM states coexist in spatially separated layers, but their mutual coupling via the interface significantly modifies the superconducting properties. An analysis of upper critical fields reveals that near the critical pressure where AFM order vanishes, the force binding superconducting electron-pairs acquires an extremely strong-coupling nature. This demonstrates that superconducting pairing can be tuned non-trivially by magnetic fluctuations (paramagnons) injected through the interface, leading to maximization of the pairing interaction., 8 pages, 9 figures

著者人数: 91名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 国城; 西村, 純; 高柳, 昌弘; 冨田, 洋; 上野, 史郎), Number of authors: 91(Affiliation. Institute of Space and Atronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS): Ebisawa, Ken; Fuke, Hideyuki; Mori, Kunishiro; Nishimura, Jun; Takayanagi, Masahiro; Tomida, Hiroshi; Ueno, Shiro), Accepted: 2018-07-03, 資料番号: SA1180102000

著者人数: 93名(所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 国城; 西村, 純; 高柳, 昌弘; 冨田, 洋; 上野, 史郎), Number of authors: 93(Affiliation. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS): Ebisawa, Ken; Fuke, Hideyuki; Mori, Kunishiro; Nishimura, Jun; Takayanagi, Masahiro; Tomida, Hiroshi; Ueno, Shiro), Accepted: 2018-07-26, 資料番号: SA1180103000

著者人数: 91名（所属. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS): 海老沢, 研; 福家, 英之; 森, 國城; 西村, 純; 高柳, 昌弘; 上野, 史郎), Accepted: 2018-02-26, 資料番号: SA1170331000

The CALorimetric Electron Telescope (CALET) space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV during a two-year mission on the International Space Station (ISS), extendable to five years. These measurements are essential to search for dark matter signatures, investigate the mechanism of cosmic-ray acceleration and propagation in the Galaxy and discover possible astrophysical sources of high-energy electrons nearby the Earth. The instrument consists of two layers of segmented plastic scintillators for the cosmic-ray charge identification (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. The instrument will be launched to the ISS within 2014 Japanese Fiscal Year (by the end of March 2015) and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF). In this paper, we will review the status and main science goals of the mission and describe the instrument configuration and performance.

Background Neuropsychiatric SLE (NPSLE) is a common manifestation of SLE and problems such as cognitive impairment or depression are elusive. The importance of innate immune related inflammation in the pathomechanism of neurodegenerative or psychiatric diseases has been recognized recently, and the importance of innate immunity in the pathogenesis of NPSLE has also been suggested1). Therefore, we investigated innate immune mechanism of NPSLE by using lupus prone mice. Objectives This study is conducted to understand the brain immune pathology of lupus-prone FcγRIIB-/-Yaa mice in which innate immune stimulation is potentiated by the duplication of Toll-like receptor 72). Methods Immune cell subsets and histopathology of brains were analyzed by flow cytometry and immunohistochemistry in FcγRIIB-/-Yaa mice compared with congenic mice at around 16 week-old when glomerulonephritis had developed. For flow cytometric analysis, microglia, myeloid lineage cells and lymphocytes were defined by staining with CD11b and CD45. Subsets of those cells and their activation status were analyzed. For histopathological analysis, microglia, brain macrophages, astrocytes and lymphocytes were immunostained and expression of MHC class I and class II were also analyzed. Results Flow cytometric analysis revealed increase in the number of microglial cells (CD11b+ CD45int) and myeloid lineage cells (CD11b+ CD45high) in the brains of FcγRIIB-/-Yaa mice compared with congenic FcγRIIB+/+ mice. Mean fluorescence intensity of MHC class I was increased in microglia and myeloid lineage cells in FcγRIIB-/-Yaa mice. An increased percentage of CD3 positive cells compared to CD19 positive cells were observed and their expression of CD69, an activation marker, were increased in FcγRIIB-/-Yaa mice. In histopathology, number of macrophages and microglia identified by Iba1 (Ionized calcium binding adapter molecule 1) positive cells were increased in FcγRIIB-/-Yaa mice. In areas where MHC class I and class II were highly expressed on macrophages, reaction of astrocytes and patchy increase of lymphocytes were also observed. Furthermore, MHC class I and class II were also highly expressed in the vascular endothelium in FcγRIIB-/-Yaa mice. Conclusions Activation of myeloid lineage cells and reactive changes of glial cells and endothelial cells were observed in the central nervous system of lupus-prone FcγRIIB-/-Yaa mice. These results imply the role of innate immune mechanisms in the pathology of NPSLE. References Stock AD, Wen J, Doerner J, et al. Neuropsychiatric systemic lupus erythematosus persists despite attenuation of systemic disease in MRL/lpr mice. J Neuroinflammation.2015;12:205. Kawano S, Lin Q, Amano H, et al. Phenotype conversion from rheumatoid arthritis to systemic lupus erythematosus by introduction of Yaa mutation into FcγRIIB-deficient C57BL/6 mice. Eur J Immunol.2013;43:770–8. Disclosure of Interest None declared

Patients with thoracic esophageal cancer are often treated by minimally invasive esophagectomy. However, the long-term survival benefits of minimally invasive esophagectomy remain unclear. Two approaches are available for thoracoscopic surgery: one with the patient in the left lateral decubitus position (LLDP), and the other with the patient in the prone position (PP). We investigated the survival benefit of thoracoscopic esophagectomy according to the tumor stage and patient position during the thoracoscopic procedure. We reviewed the records of 220 consecutive patients with esophageal cancer treated from 1998 to 2012. In total, 146 and 74 patients were treated with thoracoscopic esophagectomy in the LLDP and PP, respectively. No patients were initially proposed to be candidates for esophagectomy by thoracotomy during the study period. Data collection was performed with a focus on survival and recurrent disease. Among all the 220 patients, the overall 5-year survival rates were 83.7%, 74.1%, 45.5%, 78.6%, 44.2%, 29.4% and 24.3% in the patients with pStage IA, IB, IIA, IIB, IIIA, IIIB and IIIC disease, respectively. Despite the greater number of dissected mediastinal lymph nodes in the PP procedure, there were no significant differences in the survival curves between the LLDP and PP procedures. The long-term results of thoracoscopic esophagectomy are comparable and acceptable. The PP procedure was not confirmed to offer a superior survival benefit to the LLDP procedure in this retrospective study.

Titanium oxide films were deposited on unheated glass substrates by using inductively coupled plasma assisted reactive direct current magnetron sputtering. X-ray diffraction, X-ray photoelectron spectroscopy and field emission scanning electron microscope were used to analyze film structure, composition and morphology. Analysis results revealed the formation of titanium monoxide film rather than titanium dioxide film. Golden yellow nanocrystalline titanium monoxide film with a very high degree of crystallinity was formed under metallic mode of sputtering at lower temperature of

An inductively coupled plasma (ICP) assisted direct current (dc) magnetron sputtering system was used for depositing titanium oxide (TiOx) films on unheated glass substrates. The partial pressure of oxygen PO2 and the type of gas injection were varied to control the oxygen flux in the vicinity of the substrate. At radio frequency (rf) power to generate ICP Prf = 500 W, dc magnetron sputtering current Id = 0.8 A and total pressure PT = 0.5 Pa, a sudden decrease in the electron density Ne in the vicinity of the substrate occurs at PO2 ≈ 0.26 Pa, which corresponds to sputtering transition from metallic mode to oxide mode, and the deposition rate aD decreases significantly from ~ 10 nm/min to ~ 0.7 nm/min. When a gas mixture of oxygen and argon was lead into the chamber near the target, golden yellow TiO film with a well-crystallized structure was obtained under metallic mode of sputtering and transparent amorphous TiOx films were synthesized under oxide mode of sputtering. When oxygen was separately introduced to the vicinity of the substrate, various TiOx films with good crystallinity, including rutile and anatase, were obtained by varying PO2 under the metallic mode of sputtering. Transparent polycrystalline rutile and anatase films were grown on unheated glass substrate at aD ≈ 10 nm/min. Additionally we discussed about the low-temperature growth of crystalline TiOx films based on the results.