283 research outputs found

    Detection of extended millimeter emission in the host galaxy of 3C273 and its implications for QSO feedback via high dynamic range ALMA imaging

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    We estimate the amount of negative feedback energy injected into the ISM of the host galaxy of 3C273, a prototypical radio loud quasar. We obtained 93, 233 and 343 GHz continuum images with the Atacama Large Millimeter/Sub-millimeter Array (ALMA). After self calibration and point source subtraction, we reach an image dynamic range of 85000\sim 85000 at 93\ GHz, 39000\sim 39000 at 233\ GHz and 2500\sim 2500 at 343\ GHz. These are currently the highest image dynamic range obtained using ALMA. We detect spatially extended millimeter emission associated with the host galaxy, cospatial with the Extended Emission Line Region (EELR) observed in the optical. The millimeter spectral energy distribution and comparison with centimeter data show that the extended emission cannot be explained by dust thermal emission, synchrotron or thermal bremsstrahlung arising from massive star formation. We interpret the extended millimeter emission as thermal bremsstrahlung from gas directly ionized by the central source. The extended flux indicates that at least 7%\sim 7\% of the bolometric flux of the nuclear source was used to ionize atomic hydrogen in the host galaxy. The ionized gas is estimated to be as massive as 101010^{10} to 1011 M10^{11}\ \mathrm{M_\odot}, but the molecular gas fraction with respect to the stellar mass is consistent with other ellipticals, suggesting that direct ionization ISM by the QSO may not be sufficient to suppress star formation, or we are witnessing a short timescale before negative feedback becomes observable. The discovery of a radio counterpart to EELRs provides a new pathway to studying the QSO-host ISM interaction

    Catch performance of coastal squid jigging boats using LED panels in combination with metal halide lamps

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    Squid attracting light systems consisting of low power light emitting diode panels (LEDs) and conventional metal halide lamps (MHs) were tested to describe the influence of combinations of LEDs and MHs on squid catch. Fishing trials using LEDs (9. kW) and different numbers of MHs were carried out in August and September 2009 targeting two squid species: (1) Japanese common squid Todarodes pacificus in northern waters of the Sea of Japan (off Hokkaido) by 4 coastal squid jigging boats (19 gross tonnage) and (2) swordtip squid Photololigo edulis in western waters (off Iki) by 5 boats of the same class. Catches of both species tended to increase with the number of MHs. Generalized Linear Model analysis revealed that in addition to the number of MHs, the catch amount was influenced by fishing power (ability) of boat and by the monthly variation of squid abundance (only for P. edulis off Iki). The expected catch (number of boxes) was not proportional to the number of MHs. The largest catch was expected for P. edulis off Iki by using LEDs with 24 MHs. The optimal combination of LEDs and MHs for T. pacificus off Hokkaido was less clear because the combination with 36 MHs had the largest positive effect on the catch; this was the maximum number MHs used

    X-Ray bright optically faint active galactic nuclei in the Subaru Hyper Suprime-Cam wide survey

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    We construct a sample of X-ray bright optically faint active galactic nuclei by combining Subaru Hyper Suprime-Cam, XMM-Newton, and infrared source catalogs. 53 X-ray sources satisfying i band magnitude fainter than 23.5 mag and X-ray counts with EPIC-PN detector larger than 70 are selected from 9.1 deg^2, and their spectral energy distributions (SEDs) and X-ray spectra are analyzed. 44 objects with an X-ray to i-band flux ratio F_X/F_i>10 are classified as extreme X-ray-to-optical flux sources. SEDs of 48 among 53 are represented by templates of type 2 AGNs or starforming galaxies and show signature of stellar emission from host galaxies in the optical in the source rest frame. Infrared/optical SEDs indicate significant contribution of emission from dust to infrared fluxes and that the central AGN is dust obscured. Photometric redshifts determined from the SEDs are in the range of 0.6-2.5. X-ray spectra are fitted by an absorbed power law model, and the intrinsic absorption column densities are modest (best-fit log N_H = 20.5-23.5 cm^-2 in most cases). The absorption corrected X-ray luminosities are in the range of 6x10^42 - 2x10^45 erg s^-1. 20 objects are classified as type 2 quasars based on X-ray luminsosity and N_H. The optical faintness is explained by a combination of redshifts (mostly z>1.0), strong dust extinction, and in part a large ratio of dust/gas.Comment: 25 pages, 14 figures, 5 tables, accepted for publication in PAS

    A Wide and Deep Exploration of Radio Galaxies with Subaru HSC (WERGS). II. Physical Properties derived from the SED Fitting with Optical, Infrared, and Radio Data

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    We present physical properties of radio galaxies (RGs) with f1.4GHz>f_{\rm 1.4 GHz} > 1 mJy discovered by Subaru Hyper Supreme-Cam (HSC) and VLA Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) survey. For 1056 FIRST RGs at 0<z1.70 < z \leq 1.7 with HSC counterparts in about 100 deg2^2, we compiled multi-wavelength data of optical, near-infrared (IR), mid-IR, far-IR, and radio (150 MHz). We derived their color excess (E(BV)E (B-V)_{*}), stellar mass, star formation rate (SFR), IR luminosity, the ratio of IR and radio luminosity (qIRq_{\rm IR}), and radio spectral index (αradio\alpha_{\rm radio}) that are derived from the SED fitting with CIGALE. We also estimated Eddington ratio based on stellar mass and integration of the best-fit SEDs of AGN component. We found that E(BV)E (B-V)_{*}, SFR, and IR luminosity clearly depend on redshift while stellar mass, qIRq_{\rm IR}, and αradio\alpha_{\rm radio} do not significantly depend on redshift. Since optically-faint (iAB21.3i_{\rm AB} \geq 21.3) RGs that are newly discovered by our RG survey tend to be high redshift, they tend to not only have a large dust extinction and low stellar mass but also have high SFR and AGN luminosity, high IR luminosity, and high Eddington ratio compared to optically-bright ones. The physical properties of a fraction of RGs in our sample seem to differ from a classical view of RGs with massive stellar mass, low SFR, and low Eddington ratio, demonstrating that our RG survey with HSC and FIRST provides us curious RGs among entire RG population.Comment: 30 pages, 20 figures, and 4 tables, accepted for publication in ApJS. The catalog and SED template of radio galaxies will be accessible through an online servic

    Generation of human GAPDH knock-in reporter iPSC lines for stable expression of tdTomato in pluripotent and differentiated culture conditions

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    Human induced pluripotent stem cells (iPSCs) can differentiate into multiple cell types and are utilized for research on human development and regenerative medicine. Here, we report the establishment of human GAPDH knock-in reporter iPSC lines (GAPDH-tdT1 and 2), via CRISPR/Cas9-mediated homologous recombination, that stably express tdTomato as a constitutive cell label in both iPSCs and their differentiated derivatives. These cell lines will provide useful tools to trace cell locations and fates in 2D cultures and 3D organoids and will facilitate in vivo experiments
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