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The Linear IFMIF (International Fusion Materials Irradiation Facility) Prototype Accelerator (LIPAc) is aiming at demonstrating the low-energy section of a 40 MeV/125 mA IFMIF deuteron accelerator up to 9 MeV with a full beam current in continuous-wave operation. For such a high-power beam, the LIPAc injector is required to produce a beam current of 140 mA and 100 keV D ^+ beams. The injector commissioning to reach high beam current has been progressing at high duty cycle operation, then stable operation for many hours at a beam condition of 150 mA total extracted current. This result demonstrates that the LIPAc injector can meet the required performance for nominal 125 mA long pulse deuteron beam acceleration.

We propose a scheme to phase lock a quantum-memory control laser, frequency-conversion pump laser, and two-photon source over three octaves in frequency to operate a quantum memory. The absolute frequencies of the laser sources are determined based on a Doppler-free iodine hyperfine transition. The achieved relative frequency instability and uncertainty were ≤1 × 10 ^–12 and 3 × 10 ^–11 , respectively, which are below the requirement for operating a Pr:YSO quantum memory. This scheme simplifies the instrumentation of laser sources in a quantum repeater, and increases the reliability of quantum communication systems.

We studied the optical variability of 241 BL Lacertae (BL Lacs) and 83 flat-spectrum radio quasars (FSRQs) from the 4LAC catalog using data from the Tomo-e Gozen Northern Sky Transient Survey, with ∼50 epochs per blazar on average. We excluded blazars whose optical variability may be underestimated due to the influence of their host galaxy based on their optical luminosity ( L _O ). FSRQs with γ -ray photon index greater than 2.6 exhibit very low optical variability, and their distribution of standard deviation of repeated photometry is significantly different from that of the other FSRQs (Kolmogorov–Smirnov test p -value equal to 5 × 10 ^−6 ). Among a sample of blazars at any particular cosmological epoch, those with lower γ -ray luminosity ( L _γ ) tend to have lower optical variability, and those FSRQs with a γ -ray photon index greater than 2.6 tend to have low L _γ . We also measured the structure function of optical variability and found that the amplitude of the structure function for FSRQs is higher than previously measured and higher than that of BL Lacs at multiple time lags. Additionally, the amplitude of the structure function of FSRQs with high γ -ray photon index is significantly lower than that of FSRQs with low γ -ray photon index. The structure function of FSRQs of high γ -ray photon index shows a characteristic timescale of more than 10 days, which may be the variability timescale of the accretion disk. In summary, we infer that the optical component of FSRQs with high γ -ray photon index may be dominated by the accretion disk.

Herein, we present the statistical properties of active galactic nuclei (AGNs) for approximately 1 million member galaxies of galaxy groups and clusters with 0.1 < cluster redshift ( z _cl ) < 1.4 selected using the Subaru Hyper Suprime-Cam, the so-called CAMIRA clusters. In this research, we focused on the AGN power fraction ( f _AGN ), which is defined as the proportion of the contribution of AGNs to the total infrared (IR) luminosity, L _IR (AGN)/ L _IR , and examined how f _AGN depends on (i) z _cl and (ii) the distance from the cluster center. We compiled multiwavelength data using the ultraviolet–mid-IR range. Moreover, we performed spectral energy distribution fits to determine f _AGN using the CIGALE code with the SKIRTOR AGN model. We found that (i) the value of f _AGN in the CAMIRA clusters is positively correlated with z _cl , with the correlation slope being steeper than that for field galaxies, and (ii) f _AGN exhibits a high value at the cluster outskirts. These results indicate that the emergence of the AGN population depends on the redshift and environment and that galaxy groups and clusters at high redshifts are important in AGN evolution. Additionally, we demonstrated that cluster–cluster mergers may enhance AGN activity at the outskirts of particularly massive galaxy clusters. Our findings are consistent with a related study on the CAMIRA clusters that was based on the AGN number fraction.

In this study, we performed high-resolution near-infrared (NIR) spectroscopy ( R = 28,000; λ = 0.90–1.35 μ m) with a high signal-to-noise ratio on HD 200775, a very young (∼0.1 Myr old) and massive intermediate-mass star (a binary star with a mass of about 10 M _⊙ each) with a protoplanetary disk. The obtained spectra show eight forbidden lines of three elements: two of [S ii ] (10289 and 10323 Å), two of [N i ] (10400 and 10410 Å), and four of [Fe ii ] (12570, 12946, 12981, and 13209 Å). This is the first time that the [N i ] lines are detected in a young stellar object with a doublet deblended. Gaussian fitting of the spectra indicates that all line profiles have low-velocity components and exhibit blueshifted features, suggesting that all lines originate from the disk winds (magnetohydrodynamic disk wind and/or photoevaporative wind). Based on the fit, the [N i ] and [Fe ii ] lines are categorized into narrow components, while the [S ii ] lines are at the boundary between broad and narrow components. These forbidden lines are suggested to be very promising disk wind tracers among the existing ones because they are in the NIR-wavelength range, which can be observed from early stages with high sensitivities. Among these lines, [N i ] lines would be a rather powerful probe for deriving the basic physical parameters of disk wind gases. However, the study of these lines herein is limited to one object; thus, further studies are needed to examine their properties.

Porous Al particles with etching pits on their surfaces were prepared by anode etching using a rotating barrel. In this process, Al particles were placed in a barrel with a Pt plate electrode at the bottom. The Al particles were electrified by contacting the Pt electrode in the rotating barrel, and anode etching occurred on the surfaces of the Al particles. The structure of the etching pits formed on the surfaces of the Al particles could be controlled by adjusting the current and electrolysis time during the barrel anode etching. In addition, using an electrolyte solution with a surfactant, it was possible to form etching pits even on the surfaces of Al particles with sizes of 5 μm or less. Porous Mg particles could also be prepared by barrel anode etching using fine Mg particles as the starting material. The porous metal particles obtained using this process have a wide range of potential applications, including sensors, catalyst carriers, and batteries. [ABSTRACT FROM AUTHOR]

Outflows in an active galactic nucleus (AGN) are considered to play a key role in the evolution of the host galaxy through transfer of a large amount of energy. A narrow-line region (NLR) in the AGN is composed of ionized gas extending from parsec to kiloparsec scales. It has been suggested that shocks are required to ionize the NLR gas. If AGN outflows generate these shocks, they will sweep through the NLR, and the outflow energy will be transferred into a galaxy-scale region. In order to study the contribution of the AGN outflow to the NLR-scale shock, we measure the [Fe ii ] λ 12570/[P ii ] λ 11886 line ratio, which is a good tracer of shocks, using near-infrared spectroscopic observations with the Warm INfrared Echelle spectrograph to Realize Extreme Dispersion and sensitivity (WINERED) mounted on the New Technology Telescope. In 13 Seyfert galaxies we observed, the [Fe ii ] and [P ii ] lines were detected in 12 and 6 targets, respectively. The [Fe ii ]/[P ii ] ratios in 4 targets were found to be higher than 10, which implies the existence of shocks. We also found that the shock is likely to exist where an ionized outflow, i.e., a blue wing in [S iii ] λ 9533, is present. Our result implies that the ionized outflow present in an NLR-scale region sweeps through the interstellar medium and generates a shock.

We present an analysis of microlensing event OGLE-2019-BLG-0825. This event was identified as a planetary candidate by preliminary modeling. We find that significant residuals from the best-fit static binary-lens model exist and a xallarap effect can fit the residuals very well and significantly improves χ ^2 values. On the other hand, by including the xallarap effect in our models, we find that binary-lens parameters such as mass ratio, q , and separation, s , cannot be constrained well. However, we also find that the parameters for the source system such as the orbital period and semimajor axis are consistent between all the models we analyzed. We therefore constrain the properties of the source system better than the properties of the lens system. The source system comprises a G-type main-sequence star orbited by a brown dwarf with a period of P ∼ 5 days. This analysis is the first to demonstrate that the xallarap effect does affect binary-lens parameters in planetary events. It would not be common for the presence or absence of the xallarap effect to affect lens parameters in events with long orbital periods of the source system or events with transits to caustics, but in other cases, such as this event, the xallarap effect can affect binary-lens parameters.

We present the results of ALMA-ACA 7 m array observations in ^12 CO( J = 2–1), ^13 CO( J = 2–1), and C ^18 O( J = 2–1) line emission toward the molecular-gas disk in the Local Group spiral galaxy M33 at an angular resolution of 7.″31 × 6.″50 (30 × 26 pc). We combined the ACA 7 m array ^12 CO( J = 2–1) data with the IRAM 30 m data to compensate for emission from diffuse molecular-gas components. The ACA+IRAM combined ^12 CO( J = 2–1) map clearly depicts the cloud-scale molecular-gas structure over the M33 disk. Based on the ACA+IRAM ^12 CO( J = 2–1) cube data, we cataloged 848 molecular clouds with a mass range from 10 ^3 –10 ^6 M _⊙ . We found that high-mass clouds (≥10 ^5 M _⊙ ) tend to associate with the 8 μ m bright sources in the spiral arm region, while low-mass clouds (

We report the discoveries of low-mass free-floating planet (FFP) candidates from the analysis of 2006–2014 MOA-II Galactic bulge survey data. In this data set, we found 6111 microlensing candidates and identified a statistical sample consisting of 3535 high-quality single-lens events with Einstein radius crossing times in the range 0.057 < t _E /days < 757, including 13 events that show clear finite-source effects with angular Einstein radii of 0.90 < θ _E / μ as < 332.54. Two of the 12 events with t _E < 1 day have significant finite-source effects, and one event, MOA-9y-5919, with t _E = 0.057 ± 0.016 days and θ _E = 0.90 ± 0.14 μ as, is the second terrestrial-mass FFP candidate to date. A Bayesian analysis indicates a lens mass of ${0.75}_{-0.46}^{+1.23}$ M _⊕ for this event. The low detection efficiency for short-duration events implies a large population of low-mass FFPs. The microlensing detection efficiency for low-mass planet events depends on both the Einstein radius crossing times and the angular Einstein radii, so we have used image-level simulations to determine the detection efficiency dependence on both t _E and θ _E . This allows us to use a Galactic model to simulate the t _E and θ _E distribution of events produced by the known stellar populations and models of the FFP distribution that are fit to the data. Methods like this will be needed for the more precise FFP demographics determinations from Nancy Grace Roman Space Telescope data.

We present the first measurement of the mass function of free-floating planets (FFPs), or very wide orbit planets down to an Earth mass, from the MOA-II microlensing survey in 2006–2014. Six events are likely to be due to planets with Einstein radius crossing times t _E < 0.5 days, and the shortest has t _E = 0.057 ± 0.016 days and an angular Einstein radius of θ _E = 0.90 ± 0.14 μ as. We measure the detection efficiency depending on both t _E and θ _E with image-level simulations for the first time. These short events are well modeled by a power-law mass function, ${{dN}}_{4}/d\mathrm{log}M={({2.18}_{-1.40}^{+0.52})\times (M/8\,{M}_{\oplus })}^{-{\alpha }_{4}}$ dex ^−1 star ^−1 with ${\alpha }_{4}={0.96}_{-0.27}^{+0.47}$ for M / M _⊙ < 0.02. This implies a total of $f={21}_{-13}^{+23}$ FFPs or very wide orbit planets of mass 0.33 < M / M _⊕ < 6660 per star, with a total mass of ${80}_{-47}^{+73}{M}_{\oplus }$ star ^−1 . The number of FFPs is ${19}_{-13}^{+23}$ times the number of planets in wide orbits (beyond the snow line), while the total masses are of the same order. This suggests that the FFPs have been ejected from bound planetary systems that may have had an initial mass function with a power-law index of α ∼ 0.9, which would imply a total mass of ${171}_{-52}^{+80}{M}_{\oplus }$ star ^−1 . This model predicts that Roman Space Telescope will detect ${988}_{-566}^{+1848}$ FFPs with masses down to that of Mars (including ${575}_{-424}^{+1733}$ with 0.1 ≤ M / M _⊕ ≤ 1). The Sumi et al. large Jupiter-mass FFP population is excluded.

As a part of the “Systematic KMTNet Planetary Anomaly Search” series, we report five new planets (namely, OGLE-2016-BLG-1635Lb, MOA-2016-BLG-532Lb, KMT-2016-BLG-0625Lb, OGLE-2016-BLG-1850Lb, and KMT-2016-BLG-1751Lb) and one planet candidate (KMT-2016-BLG-1855), which were found by searching 2016 KMTNet prime fields. These buried planets show a wide range of masses from Earth-class to super-Jupiter-class and are located in both the disk and the bulge. The ultimate goal of this series is to build a complete planet sample. Because our work provides a complementary sample to other planet detection methods, which have different detection sensitivities, our complete sample will help us to obtain a better understanding of planet demographics in our Galaxy.

The temperature structure of protoplanetary disks provides an important constraint on where in the disks rocky planets like our own form. Recent nonideal magnetohydrodynamical (MHD) simulations have shown that the internal Joule heating associated with magnetically driven disk accretion is inefficient at heating the disk midplane. A disk temperature model based on the MHD simulations predicts that in a disk around a solar-mass young star, the water snow line can move inside the current Earth’s orbit within 1 Myr after disk formation. However, the efficiency of the internal Joule heating depends on the disk’s ionization and opacity structures, both of which are governed by dust grains. In this study, we investigate these effects by combining the previous temperature model for magnetically accreting disks with a parameterized model for the grain size and vertical distribution. Grain growth enhances the gas ionization fraction and thereby allows Joule heating to occur closer to the midplane. However, growth beyond 10 μ m causes a decrease in the disk opacity, leading to a lower midplane temperature. The combination of these two effects results in the midplane temperature being maximized when the grain size is in the range 10–100 μ m. Grain growth to millimeter sizes can also delay the snow line’s migration to the 1 au orbit by up to a few million years. We conclude that accounting for dust growth is essential for accurately modeling the snow line evolution and terrestrial planet formation in magnetically accreting protoplanetary disks.

The nature of molecular clouds and their statistical behavior in subsolar metallicity environments are not fully explored yet. We analyzed data from an unbiased CO ( J = 2–1) survey at the spatial resolution of ∼2 pc in the northern region of the Small Magellanic Cloud with the Atacama Compact Array to characterize the CO cloud properties. A cloud-decomposition analysis identified 426 spatially/velocity-independent CO clouds and their substructures. Based on the cross-matching with known infrared catalogs by Spitzer and Herschel, more than 90% CO clouds show spatial correlations with point sources. We investigated the basic properties of the CO clouds and found that the radius–velocity linewidth ( R – σ _v ) relation follows the Milky Way-like power-law exponent, but the intercept is ∼1.5 times lower than that in the Milky Way. The mass functions ( dN / dM ) of the CO luminosity and virial mass are characterized by an exponent of ∼1.7, which is consistent with previously reported values in the Large Magellanic Cloud and in the Milky Way.

The PRime-focus Infrared Microlensing Experiment (PRIME) will be the first to conduct a dedicated near-infrared microlensing survey by using a 1.8 m telescope with a wide field of view of 1.45 deg ^2 at the South African Astronomical Observatory. The major goals of the PRIME microlensing survey are to measure the microlensing event rate in the inner Galactic bulge to help design the observing strategy for the exoplanet microlensing survey by the Nancy Grace Roman Space Telescope and to make a first statistical measurement of exoplanet demographics in the central bulge fields where optical observations are very difficult owing to the high extinction in these fields. Here we conduct a simulation of the PRIME microlensing survey to estimate its planet yields and determine the optimal survey strategy, using a Galactic model optimized for the inner Galactic bulge. In order to maximize the number of planet detections and the range of planet mass, we compare the planet yields among four observation strategies. Assuming the Cassan et al. mass function as modified by Penny et al., we predict that PRIME will detect planetary signals for 42–52 planets (1–2 planets with M _p ≤ 1 M _⊕ , 22−25 planets with mass 1 M _⊕ < M _p ≤ 100 M _⊕ , 19–25 planets 100 M _⊕ < M _p ≤ 10, 000 M _⊕ ), per year depending on the chosen observation strategy.

The bottleneck for the production of biofuels from microalgae consists on costly harvesting processes and low lipid production, immobilization technology could play a part on making the production of biofuels more feasible. The aim of this study was to evaluate the effect of alginate immobilization on the growth and lipid productivity of the microalgae Chlorella sorokiniana , so far, the main focus of immobilization technology has been its use for wastewater treatment and nutrient removal from effluents. The microalgae Chlorella sorokiniana was cultured in both free and immobilized forms under optimal autotrophic growth conditions. Microalgae were immobilized in calcium alginate beads generated by mixing algal cells with a sodium alginate solution, followed by extrusion into a CaCl _2 solution. The results obtained in this study showed that the growth of the microalgae immobilized in alginate beads, was enhanced and achieved a dry cell weight 1.4-fold higher than that of a free cell culture, a higher light transmittance was also achieved in the alginate immobilized culture, and the lipid productivity was increased from 54.21 ± 2.48 mg l ^−1 d in the free cell culture to 82.22 ± 8.48 mg l ^−1 d in the immobilized culture. These results demonstrate the effectiveness of immobilization technology for promoting growth and lipid productivity in the microalgae Chlorella sorokiniana .

We analyze the MOA-2020-BLG-208 gravitational microlensing event and present the discovery and characterization of a new planet, MOA-2020-BLG-208Lb, with an estimated sub-Saturn mass. With a mass ratio $q={3.17}_{-0.26}^{+0.28}\times {10}^{-4}$ , the planet lies near the peak of the mass-ratio function derived by the MOA collaboration and near the edge of expected sample sensitivity. For these estimates we provide results using two mass-law priors: one assuming that all stars have an equal planet-hosting probability, and the other assuming that planets are more likely to orbit around more massive stars. In the first scenario, we estimate that the lens system is likely to be a planet of mass ${m}_{\mathrm{planet}}={46}_{-24}^{+42}\,{M}_{\oplus }$ and a host star of mass ${M}_{\mathrm{host}}={0.43}_{-0.23}^{+0.39}\,{M}_{\odot }$ , located at a distance ${D}_{L}={7.49}_{-1.13}^{+0.99}\,\mathrm{kpc}$ . For the second scenario, we estimate ${m}_{\mathrm{planet}}={69}_{-34}^{+37}\,{M}_{\oplus }$ , ${M}_{\mathrm{host}}={0.66}_{-0.32}^{+0.35}\,{M}_{\odot }$ , and ${D}_{L}={7.81}_{-0.93}^{+0.93}\,\mathrm{kpc}$ . The planet has a projected separation as a fraction of the Einstein ring radius $s={1.3807}_{-0.0018}^{+0.0018}$ . As a cool sub-Saturn-mass planet, this planet adds to a growing collection of evidence for revised planetary formation models.

We present the analysis of three more planets from the KMTNet 2021 microlensing season. KMT-2021-BLG-0119Lb is a ∼6 M _Jup planet orbiting an early M dwarf or a K dwarf, KMT-2021-BLG-0192Lb is a ∼2 M _Nep planet orbiting an M dwarf, and KMT-2021-BLG-2294Lb is a ∼1.25 M _Nep planet orbiting a very-low-mass M dwarf or a brown dwarf. These by-eye planet detections provide an important comparison sample to the sample selected with the AnomalyFinder algorithm, and in particular, KMT-2021-BLG-2294 is a case of a planet detected by eye but not by algorithm. KMT-2021-BLG-2294Lb is part of a population of microlensing planets around very-low-mass host stars that spans the full range of planet masses, in contrast to the planet population at ≲0.1 au, which shows a strong preference for small planets.

Numerous studies have investigated the hotspots for reducing carbon emissions associated with household consumption, including reducing household carbon footprints (CFs) and greener lifestyle choices, such as living car-free, eating less meat, and having one less child. However, estimating the effect of each of these actions requires the simultaneous consideration of lifestyle choices and household characteristics that could also affect the household CF. Here, we quantify the reduction in household CFs for 25 factors associated with individual lifestyle choices or socioeconomic characteristics. This study linked approximately 42 000 microdata on consumption expenditure with the Japanese subnational 47 prefecture-level multi-regional input–output table, which are both the finest-scale data currently available. We improved the accuracy of household CF calculations by considering regional heterogeneity, and successfully estimated the magnitude of household CF reduction associated with individual lifestyle choices and socioeconomics. For example, it was found that moving from a cold region to a region with mild climate would have considerable potential for reducing the CO _2 emissions of a household, all other factors being equal. In addition, a household residing in a house that meets the most recent energy standards emits 1150 kg less CO _2 per year than if they reside in a house that meets previous energy standards. Ownership and use of durable goods also had the potential for reducing the CO _2 emissions of a household; a normal-sized car, a personal computer, a compact car, and a bidet were associated with CO _2 emissions of 922, 712, 421, and 345 kg per year, respectively. The findings therefore have important implications for climate change mitigation and policy measures associated with lifestyle.