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Massive colliding-wind binaries that host a Wolf–Rayet (WR) star present a potentially important source of dust and chemical enrichment in the interstellar medium. However, the chemical composition and survival of dust formed from such systems is not well understood. The carbon-rich Wolf–Rayet binary WR 140 presents an ideal astrophysical laboratory for investigating these questions, given its well-defined orbital period and predictable dust-formation episodes every 7.93 years around periastron passage. We present observations from our Early Release Science programme (ERS 1349) with the James Webb Space Telescope Mid-Infrared Instrument (MIRI) Medium-Resolution Spectrometer and Imager that reveal the spectral and spatial signatures of nested circumstellar dust shells around WR 140. MIRI medium-resolution spectroscopy of the second dust shell and Imager detections of over 17 shells formed throughout approximately the past 130 years confirm the survival of carbonaceous dust grains from WR 140 that are probably carriers of ‘unidentified infrared’-band features at 6.4 and 7.7 μm. The observations indicate that dust-forming carbon-rich Wolf–Rayet binaries can enrich the interstellar medium with organic compounds and carbonaceous dust.

Since their first discovery in the late 1960s, gamma-ray bursts have attracted an exponentially growing interest from the international community due to their central role in the most highly debated open questions of the modern research of astronomy, astrophysics, cosmology, and fundamental physics. These range from the intimate nuclear composition of high-density material within the core of ultra-dense neuron stars, to stellar evolution via the collapse of massive stars, the production and propagation of gravitational waves, as well as the exploration of the early universe by unveiling the first stars and galaxies (assessing also their evolution and cosmic re-ionization). GRBs in the past ∼50 years have stimulated the development of cutting-edge technological instruments for observations of high-energy celestial sources from space, leading to the launch and successful operations of many different scientific missions (several of them still in data-taking mode currently). In this review, we provide a brief description of the GRB-dedicated missions from space being designed and developed for the future. The list of these projects, not meant to be exhaustive, shall serve as a reference to interested readers to understand what is likely to come next to lead the further development of GRB research and the associated phenomenology.

Observing high resolution optical to infrared spectra is crucial to understanding how energy is generated in galaxies. We present follow-up optical Keck-II/DEIMOS and infrared Keck-I/MOSFIRE spectra of ∼200 galaxies in the AKARI/North Ecliptic Pole Deep survey region at intermediate redshift. From rest-frame optical emission lines, we classify most of our objects as star-forming (53%), with the MIR selection favoring relatively massive galaxies (median log M/M⊙∼ 10.3). In addition, we combine our spectroscopic redshifts with UV to FIR photometry as inputs in order to model SEDs with CIGALE, and we measure the PAH 7.7 μm luminosity as an SFR indicator.

Mid-infrared images frequently suffer artifacts and extended point-spread functions (PSFs). We investigate the characteristics of the artifacts and the PSFs in images obtained with the infrared camera (IRC) on board AKARI at four mid-infrared bands of the S7 (7A I14m), S11 (11A I14m), L15 (15A I14m), and L24 (24A I14m). Removal of the artifacts significantly improves the reliability of the reference data for flat-fielding at the L15 and L24 bands. A set of models of the IRC PSFs is also constructed from on-orbit data. These PSFs have extended components that come from diffraction and scattering within the detector arrays. We estimate the aperture correction factors for point sources and the surface brightness correction factors for diffuse sources. We conclude that the surface brightness correction factors range from 0.95 to 0.8, taking account of the extended component of the PSFs. To correct for the extended PSF effects for the study of faint structures, we also develop an image reconstruction method, which consists of the deconvolution with the PSF and the convolution with an appropriate Gaussian. The appropriate removal of the artifacts, improved flat-fielding, and image reconstruction with the extended PSFs enable us to investigate detailed structures of extended sources in IRC mid-infrared images.

Mid-infrared images frequently suffer artifacts and extended point-spread functions (PSFs). We investigate the characteristics of the artifacts and the PSFs in images obtained with the infrared camera (IRC) on boardAKARIat four mid-infrared bands of the S7 (7 μm), S11 (11 μm), L15 (15 μm), and L24 (24 μm). Removal of the artifacts significantly improves the reliability of the reference data for flat-fielding at the L15 and L24 bands. A set of models of the IRC PSFs is also constructed from on-orbit data. These PSFs have extended components that come from diffraction and scattering within the detector arrays. We estimate the aperture correction factors for point sources and the surface brightness correction factors for diffuse sources. We conclude that the surface brightness correction factors range from 0.95 to 0.8, taking account of the extended component of the PSFs. To correct for the extended PSF effects for the study of faint structures, we also develop an image reconstruction method, which consists of the deconvolution with the PSF and the convolution with an appropriate Gaussian. The appropriate removal of the artifacts, improved flat-fielding, and image reconstruction with the extended PSFs enable us to investigate detailed structures of extended sources in IRC mid-infrared images.

Using extensive mid-IR datasets from AKARI, i.e. 9 band photometry covering the wavelength range from 2 μm to 24 μm and the unbiased spectroscopic survey for sources with Sν (9μm)>0.3 mJy, we investigated the PAHs emission features in distant starburst galaxies. PAH-selected galaxies, selected with an extremely red mid-IR colour due to PAHs, are found to have a peculiar rest-frame 11-to-8 μm flux ratio, which is systematically smaller than nearby starburst/AGN spectral templates. This may indicate a systematic difference in the physical condition of the ISM between nearby and distant starburst galaxies.

We study the mass–metallicity relation and fundamental relation (FMR) for infrared bright galaxies (IR galaxies) at z ~ 0.9 discovered by AKARI NEP-Deep survey. The main result of this work is that metallicity of IR galaxies surprisingly match optical selected galaxies at a given mass even their star formation rates are different, which may imply that optical and IR selected galaxies follow similar star formation histories, and the starbursts in the IR galaxies do not give a strong impact in changing metallicity because of the short duration time.

DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consist of three drag-free spacecraft, 1000 km apart from each other, whose relative displacements are measured by a differential Fabry-Perot interferometer. We plan to launch DECIGO in middle of 2020s, after sequence of two precursor satellite missions, DECIGO pathfinder and Pre-DECIGO, for technology demonstration required to realize DECIGO and hopefully for detection of gravitational waves from our galaxy or nearby galaxies.

JASMINE (Japan Astrometry Satellite Mission for INfrared Exploration) is a mission to determine positions and parallaxes accurate to $\\sim 10$ $\\mu$arcsec, with proper motion errors $\\sim 10$ $\\mu$arcsec yr$^{-1}$ for Galactic stars observed in the z-band (0.9 $\\mu$m). In this article, we report some technical investigations.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Polycyclic aromatic hydrocarbon (PAH) dust emission has been proposed as an effective extinction-independent star formation rate (SFR) indicator in the mid-infrared (MIR), but this may depend on conditions in the interstellar medium. The coverage of the AKARI/Infrared Camera (IRC) allows us to study the effects of metallicity, starburst intensity, and active galactic nuclei on PAH emission in galaxies with \\(f_{\\nu}(L18W)\\lesssim 19\\) AB mag. Observations include follow-up, rest-frame optical spectra of 443 galaxies within the AKARI North Ecliptic Pole survey that have IRC detections from 7-24 \\(\\mu\\)m. We use optical emission line diagnostics to infer SFR based on H\\(\\alpha\\) and [O II]\\(\\lambda\\lambda 3726,3729\\) emission line luminosities. The PAH 6.2 \\(\\mu\\)m and PAH 7.7 \\(\\mu\\)m luminosities (\\(L(PAH\\ 6.2\\ \\mu m)\\) and \\(L(PAH\\ 7.7\\ \\mu m)\\), respectively) derived using multi-wavelength model fits are consistent with those derived from slitless spectroscopy within 0.2 dex. \\(L(PAH\\ 6.2\\ \\mu m)\\) and \\(L(PAH\\ 7.7\\ \\mu m)\\) correlate linearly with the 24 \\(\\mu\\)m-dust corrected H\\(\\alpha\\) luminosity only for normal, star-forming ``main-sequence\" galaxies. Assuming multi-linear correlations, we quantify the additional dependencies on metallicity and starburst intensity, which we use to correct our PAH SFR calibrations at \\(0

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