Browsing by Author "Yang, C."

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    Electrostatically promoted dynamic hybridization of glucans with cationic polythiophene
    (2016) Fukuhara, G.; Imai, M.; Fuentealba Patiño, Denis Alberto; Ishida, Y.; Kurohara, H.; Yang, C.; Mori, T.; Uyama, H.; Bohne, C.; Inoue, Y.
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    H2O emission in high-z ultra-luminous infrared galaxies
    (2013) Omont, A.; Yang, C.; Cox, P.; Neri, R.; Beelen, A.; Bussmann, R. S.; Gavazzi, R.; van der Werf, P.; Riechers, D.; Downes, D.; Krips, M.; Dye, S.; Ivison, R.; Vieira, J. D.; Weiss, A.; Aguirre, J. E.; Baes, M.; Baker, A. J.; Bertoldi, F.; Cooray, A.; Dannerbauer, H.; De Zotti, G.; Eales, S. A.; Fu, H.; Gao, Y.; Guelin, M.; Harris, A. I.; Jarvis, M.; Lehnert, M.; Leeuw, L.; Lupu, R.; Menten, K.; Michalowski, M. J.; Negrello, M.; Serjeant, S.; Temi, P.; Auld, R.; Dariush, A.; Dunne, L.; Fritz, J.; Hopwood, R.; Hoyos, C.; Ibar, E.; Maddox, S.; Smith, M. W. L.; Valiante, E.; Bock, J.; Bradford, C. M.; Glenn, J.; Scott, K. S.
    Using the IRAM Plateau de Bure interferometer (PdBI), we report the detection of water vapor in six new lensed ultra-luminous starburst galaxies at high redshift, discovered in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). The sources are detected either in the 2(02)-1(11) or 2(11)-2(02) H2O emission lines with integrated line fluxes ranging from 1.8 to 14 Jy km s(-1). The corresponding apparent luminosities are mu L-H2O similar to 3-12 x 10(8) L-circle dot, where mu is the lensing magnification factor (3 < mu < 12). These results confirm that H2O lines are among the strongest molecular lines in high-z ultra-luminous starburst galaxies, with intensities almost comparable to those of the high-J CO lines, and similar profiles and line widths (similar to 200-900 km s(-1)). With the current sensitivity of the PdBI, the water lines can therefore easily be detected in high-z lensed galaxies (with F(500 mu m) > 100 mJy) discovered in the Herschel surveys. Correcting the luminosities for amplification, using existing lensing models, L-H2O is found to have a strong dependence on the infrared luminosity, varying as similar to L-IR(1.2). This relation, which needs to be confirmed with better statistics, may indicate a role of radiative (infrared) excitation of the H2O lines, and implies that high-z galaxies with L-IR greater than or similar to 10(13) L-circle dot tend to be very strong emitters in water vapor, that have no equivalent in the local universe.
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    NuSTAR OBSERVATIONS OF MAGNETAR 1E 1048.1-5937
    (2016) Yang, C.; Archibald, R. F.; Vogel, J. K.; An, H.; Kaspi, V. M.; Guillot, S.; Beloborodov, A. M.; Pivovaroff, M.
    We report on simultaneous Nuclear Spectroscopic Telescope Array (NuSTAR) and XMM-Newton observations of the magnetar 1E. 1048.1-5937, along with Rossi X-ray Timing Explorer (RXTE) data for the same source. The NuSTAR data provide a clear detection of this magnetar's persistent emission up to 20 keV. We detect a previously unreported small secondary peak in the average pulse profile in the 7-10 keV band, which grows to an amplitude comparable to that of the main peak in the 10-20 keV band. We show using RXTE data that this secondary peak is likely transient. We find that the pulsed fraction increases with energy from a value of similar to 0.55 at similar to 2. keV to a value of similar to 0.75 near 8. keV but shows evidence of decreasing at higher energies. After filtering out multiple bright X-ray bursts during the observation, we find that the phase-averaged spectrum from combined NuSTAR and XMM data is well described by an absorbed double blackbody plus power-law model, with no evidence for the spectral turn-up near similar to 10. keV as has been seen in some other magnetars. Our data allow us to rule out a spectral turn-up similar to those seen in magnetars 4U 0142+61 and 1E 2259+586 of Delta Gamma greater than or similar to 2, where Delta Gamma is the difference between the soft-band and hard-band photon indexes. The lack of spectral turn-up is consistent with what has been observed from an active subset of magnetars given previously reported trends suggesting that the degree of spectral turn-up is correlated with spin-down rate and/or spin-inferred magnetic field.
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    VALES V : a kinematic analysis of the molecular gas content in H-ATLAS galaxies at z similar to 0.03-0.35 using ALMA
    (2019) Molina, J.; Ibar, Edo; Villanueva, V.; Escala, A.; Cheng, C.; Baes, M.; Messias, H.; Yang, C.; Bauer, Franz Erik; Werf, van der