We present the results of an unbiased asteroid survey in the mid-infrared wavelength region with the Infrared Camera (IRC) on board the Japanese infrared satellite AKARI. About 20% of the point source events recorded in the AKARI All-Sky Survey observations are not used for the IRC Point Source Catalog (IRC-PSC) in its production process because of a lack of multiple detection by position. Asteroids, which are moving objects on the celestial sphere, remain in these "residual events". We identify asteroids out of the residual events by matching them with the positions of known asteroids. For the identified asteroids, we calculate the size and albedo based on the Standard Thermal Model. Finally we have a new brand of asteroid catalog, named the Asteroid Catalog Using AKARI (AcuA), which contains 5120 objects, about twice as many as the IRAS asteroid catalog. The catalog objects comprise 4953 main belt asteroids, 58 near-Earth asteroids, and 109 Jovian Trojan asteroids. The catalog is publicly available via the Internet.

Context. AKARI is the first Japanese astronomical satellite dedicated to infrared astronomy. One of the main purposes of AKARI is the all-sky survey performed with six infrared bands between 9 μm and 200 μm during the period from 2006 May 6 to 2007 August 28. In this paper, we present the mid-infrared part (9 μm and 18 μm bands) of the survey carried out with one of the on-board instruments, the infrared camera (IRC). Aims. We present unprecedented observational results of the 9 μm and 18 μm AKARI all-sky survey and detail the operation and data processing leading to the point source detection and measurements. Methods. The raw data are processed to produce small images for every scan, and the point sources candidates are derived above the 5σ noise level per single scan. The celestial coordinates and fluxes of the events are determined statistically and the reliability of their detections is secured through multiple detections of the same source within milli-seconds, hours, and months from each other. Results. The sky coverage is more than 90% for both bands. A total of 877 091 sources (851 189 for 9 μm, 195 893 for 18 μm) are confirmed and included in the current release of the point source catalog. The detection limit for point sources is 50 mJy and 90 mJy for the 9 μm and 18 μm bands, respectively. The position accuracy is estimated to be better than 2 . Uncertainties in the in-flight absolute flux calibration are estimated to be 3% for the 9 μm band and 4% for the 18 μm band. The coordinates and fluxes of detected sources in this survey are also compared with those of the IRAS survey and are found to be statistically consistent.

The Infrared Camera (IRC) is one of two focal-plane instruments on the AKARI 1 satellite. It is designed for wide-field deep imaging and low-resolution spectroscopy in the near-to mid-infrared (1.8-26.5 µm) in the pointed observation mode of AKARI. IRC is also operated in the survey mode to make an all-sky survey at 9 and 18 µm. It comprises three channels. The NIR channel (1.8-5.5 µm) employs a 512 × 412 InSb array, whereas both the MIR-S (4.6-13.4 µm) and MIR-L (12.6-26.5 µm) channels use 256 × 256 Si:As impurity band conduction arrays. Each of the three channels has a field-of-view of about 10 ′ × 10 ′ and are operated simultaneously. The NIR and MIR-S share the same field-of-view by virtue of a beam splitter. The MIR-L observes the sky about 25 ′ away from the NIR/MIR-S field-of-view. IRC gives us deep insights into the formation and evolution of galaxies, the evolution of planetary disks, the process of star-formation, the properties of interstellar matter under various physical conditions, and the nature and evolution of solar system objects. The in-flight performance of IRC has been confirmed to be in agreement with the pre-flight expectation. This paper summarizes the design and the in-flight operation and imaging performance of IRC.

AKARI, the first Japanese satellite dedicated to infrared astronomy, was launched on 2006 February 21, and started observations in May of the same year. AKARI has a 68.5 cm cooled telescope, together with two focal-plane instruments, which survey the sky in six wavelength bands from mid–to far-infrared. The instruments also have a capability for imaging and spectroscopy in the wavelength range 2-180$\mu$m in the pointed observation mode, occasionally inserted into a continuous survey operation. The in-orbit cryogen lifetime is expected to be one and a half years. The All-Sky Survey will cover more than 90% of the whole sky with a higher spatial resolution and a wider wavelength coverage than that of the previous IRAS all-sky survey. Point-source catalogues of the All-Sky Survey will be released to the astronomical community. Pointed observations will be used for deep surveys of selected sky areas and systematic observations of important astronomical targets. These will become an additional future heritage of this mission.

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Context. The edge-on starburst galaxy M 82 exhibits complicated distributions of gaseous materials in its halo, which include ionized superwinds driven by nuclear starbursts, neutral materials entrained by the superwinds, and large-scale neutral streamers probably caused by a past tidal interaction with M 81. Aims. We investigate detailed distributions of dust grains and polycyclic aromatic hydrocarbons (PAHs) around M 82 to understand their interplay with the gaseous components. Methods. We performed mid-(MIR) and far-infrared (FIR) observations of M 82 with the infrared camera (IRC) and far-infrared surveyor (FIS) onboard AKARI. Results. We obtained new MIR and FIR images of M 82, which reveal both faint extended emission in the halo and very bright emission in the center with signal dynamic ranges as broad as five orders of magnitude for the MIR and three for FIR, respectively. We detected MIR and FIR emission in the regions far away from the disk of the galaxy, reflecting the dust and PAHs in the halo of M 82. Conclusions. We find that the dust and PAHs are contained in both ionized and neutral gas components, implying that they have been expelled into the halo of M 82 by both starbursts and galaxy interaction. In particular, we obtain a tight correlation between the PAH and Hα emission, which provides evidence that the PAHs are well mixed in the ionized superwind gas and flowing out from the disk.

The spring-type near isogenic line (NIL) of the winter-type barley (Hordeum vulgare ssp. vulgare) var. Hayakiso 2 (HK2) was developed by introducing VERNALIZATION-H1 (Vrn-H1) for spring growth habit from the spring-type var. Indo Omugi. Contrary to expectations, the spring-type NIL flowered later than winter-type HK2. This phenotypic difference was controlled by a single gene, which cosegregated only with phytochrome C (HvPhyC) among three candidates around the Vrn-H1 region (Vrn-H1, HvPhyC, and CASEIN KINASE IIa), indicating that HvPhyC was the most likely candidate gene. Compared with the late-flowering allele HvPhyC-l from the NIL, the early-flowering allele HvPhyC-e from HK2 had a single nucleotide polymorphism T1139C in exon 1, which caused a nonsynonymous amino acid substitution of phenylalanine at position 380 by serine in the functionally essential GAF (39, 59-cyclic-GMP phosphodiesterase, adenylate cyclase, formate hydrogen lyase activator protein) domain. Functional assay using a rice (Oryza sativa) phyA phyC double mutant line showed that both of the HvPhyC alleles are functional, but HvPhyC-e may have a hyperfunction. Expression analysis using NILs carrying HvPhyC-e and HvPhyC-l (NIL [HvPhyC-e] and NIL [HvPhyC-l], respectively) showed that HvPhyC-e up-regulated only the flowering promoter FLOWERING LOCUS T1 by bypassing the circadian clock genes and flowering integrator CONSTANS1 under a long photoperiod. Consistent with the up-regulation, NIL (HvPhyC-e) flowered earlier than NIL (HvPhyC-l) under long photoperiods. These results implied that HvPhyC is a key factor to control long-day flowering directly.

Infrared (IR) luminosity is fundamental to understanding the cosmic star formation history and active galactic nuclei (AGN) evolution, since their most intense stages are often obscured by dust. However, local IR luminosity function estimates today are still based on the IRAS survey in the 1980s, with wavelength coverage only up to 100 μm. The AKARI IR space telescope performed an all‐sky survey in six IR bands (9, 18, 65, 90, 140 and 160 μm) with 3–10 times better sensitivity, covering the crucial far‐IR wavelengths across the peak of the dust emission. Combined with a better spatial resolution, AKARI can much more precisely measure the total infrared luminosity (LTIR) of individual galaxies, and thus, the total infrared luminosity density in the local Universe. By fitting modern IR spectral energy distribution (SED) models, we have remeasured LTIR of the IRAS Revised Bright Galaxy Sample, which is a complete sample of local galaxies with S60 μm > 5.24 Jy. We present mid‐IR monochromatic luminosity (νLν) to LTIR correlations for Spitzer8 μm, AKARI9 μm, IRAS12 μm, WISE12 μm, ISO15 μm, AKARI18 μm, WISE22 μm and Spitzer24 μm filters. These measures of LMIR are well correlated with LTIR, with scatter in the range 13–44 per cent. The best‐fitting LMIR‐to‐LTIR conversions provide us with estimates of LTIR using only a single MIR band, in which several deep all‐sky surveys are becoming available such as AKARI MIR and WISE. Although we have found some overestimates of LTIR by IRAS due to contaminating cirrus/sources, the resulting AKARI IR luminosity function (LF) agrees well with that from IRAS. We integrate the LF weighted by LTIR to obtain a cosmic IR luminosity density of ΩTIR= (8.5+1.5−2.3) × 107  L⊙ Mpc−3, of which 7 ± 1 per cent is produced by luminous infrared galaxies (LIRGs) (LTIR > 1011  L⊙), and only 0.4 ± 0.1 per cent is from ultraluminous infrared galaxies (ULIRGs) (LTIR > 1012  L⊙) in the local Universe, in stark contrast to high‐redshift results. We separate the contributions from AGN and star‐forming galaxies (SFGs). The SFG IR LF shows a steep decline at the bright end. Combined with high‐redshift results from the AKARI NEP deep survey, these data show a strong evolution of ΩSFTIR∝ (1 +z)4.0±0.5 and ΩAGNTIR∝ (1 +z)4.4±0.4. For ΩAGNTIR, the ULIRG contribution exceeds that from LIRGs already by z∼ 1. A rapid evolution in both ΩAGNTIR and ΩSFGTIR suggests the correlation between star formation and black hole accretion rate continues up to higher redshifts. We compare the evolution of ΩAGNTIR to that of X‐ray luminosity density. The ΩAGNTIR/ΩX‐ray AGN ratio shows a possible increase at z > 1, suggesting an increase of obscured AGN at z > 1.