Zobrazeno 1 - 10
of 79
pro vyhledávání: '"Murakawa, Koji"'
We study the $3~\mu$m scattering feature of water ice detected in the outer disk of HD 142527 by performing radiative transfer simulations. We show that an ice mass abundance at the outer disk surface of HD 142527 is much lower than estimated in a pr
Externí odkaz:
http://arxiv.org/abs/2108.08637
Water ice has a strong spectral feature at a wavelength of approximately $3~\mu$m, which plays a vital role in our understanding of the icy universe. In this study, we investigate the scattering polarization of this water-ice feature. The linear pola
Externí odkaz:
http://arxiv.org/abs/2101.07635
Ring formation by coagulation of dust aggregates in early phase of disk evolution around a protostar
Autor:
Ohashi, Satoshi, Kobayashi, Hiroshi, Nakatani, Riouhei, Okuzumi, Satoshi, Tanaka, Hidekazu, Murakawa, Koji, Zhang, Yichen, Liu, Hauyu Baobab, Sakai, Nami
Ring structures are observed by (sub-)millimeter dust continuum emission in various circumstellar disks from early stages of Class 0 and I to late stage of Class II young stellar objects (YSOs). In this paper, we study one of the possible scenarios o
Externí odkaz:
http://arxiv.org/abs/2012.04082
Autor:
Kataoka, Akimasa, Tsukagoshi, Takashi, Momose, Munetake, Nagai, Hiroshi, Muto, Takayuki, Dullemond, Cornelis P., Pohl, Adriana, Fukagawa, Misato, Shibai, Hiroshi, Hanawa, Tomoyuki, Murakawa, Koji
We present the polarization observations toward the circumstellar disk around HD 142527 by using Atacama Large Millimeter/submillimeter Array (ALMA) at the frequency of 343 GHz. The beam size is $0.51 " \times 0.44 "$, which corresponds to the spatia
Externí odkaz:
http://arxiv.org/abs/1610.06318
Autor:
Kataoka, Akimasa, Muto, Takayuki, Momose, Munetake, Tsukagoshi, Takashi, Fukagawa, Misato, Shibai, Hiroshi, Hanawa, Tomoyuki, Murakawa, Koji, Dullemond, Cornelis P.
We present a new method to constrain the grain size in protoplanetary disks with polarization observations at millimeter wavelengths. If dust grains are grown to the size comparable to the wavelengths, the dust grains are expected to have a large sca
Externí odkaz:
http://arxiv.org/abs/1504.04812
Autor:
Groh, Jose H., Nielsen, Krister E., Damineli, Augusto, Gull, Theodore R., Madura, Thomas I., Hillier, D. J., Teodoro, Mairan, Driebe, Thomas, Weigelt, Gerd, Hartman, Henrik, Kerber, Florian, Okazaki, Atsuo T., Owocki, Stan P., Millour, Florentin, Murakawa, Koji, Kraus, Stefan, Hofmann, Karl-Heinz, Schertl, Dieter
We report near-IR spectroscopic observations of the Eta Carinae massive binary system during 2008-2009 using VLT/CRIRES. We detect a strong, broad absorption wing in He I 10833 extending up to -1900 km/s across the 2009.0 spectroscopic event. Archiva
Externí odkaz:
http://arxiv.org/abs/1003.4527
Autor:
Millour, Florentin, Driebe, Thomas, Chesneau, Olivier, Groh, José, Hofmann, Karl-Heinz, Murakawa, Koji, Ohnaka, Keiichi, Schertl, Dieter, Weigelt, Gerd
Publikováno v:
Astronomy and Astrophysics (2009)
Most Wolf-Rayet stars (WR) of WC9 sub-type exhibit a dusty circumstellar envelope, but it is still a matter of debate how dust can form in their harsh environment. In a few cases, a pinwheel-like structure of the dusty envelope has been detected. The
Externí odkaz:
http://arxiv.org/abs/0909.4207
Publikováno v:
Astron.J.133:1345-1360,2007
The structure of the dusty circumstellar envelopes (CSEs) of proto-planetary nebulae (PPNs) reveals the mass-loss history of these sources and how such histories may differ for elliptical (SOLE) and bipolar (DUPLEX) PPNs. To study the PPN structures
Externí odkaz:
http://arxiv.org/abs/astro-ph/0701880
Autor:
Naoi, Takahiro, Tamura, Motohide, Nagata, Tetsuya, Nakajima, Yasushi, Suto, Hiroshi, Murakawa, Koji, Kandori, Ryo, Sasaki, Sho, Nishiyama, Shogo, Oasa, Yumiko, Sugitani, Koji
We have conducted J, H, and Ks imaging observations for the Coalsack Globule 2 with the SIRIUS infrared camera on the IRSF 1.4 m telescope at SAAO, and determined the color excess ratio, E(J-H)/E(H-Ks). The ratio is determined in the same photometric
Externí odkaz:
http://arxiv.org/abs/astro-ph/0612620
Publikováno v:
Astrophys.J.641:1113-1121,2006
We present the results of proper-motion measurements of the dust shell structure in the Egg Nebula (AFGL 2688, CRL 2688, V1610 Cyg), based on the archived two-epoch imaging-polarimetry data in the 2 micron band taken with NICMOS on-board the Hubble S
Externí odkaz:
http://arxiv.org/abs/astro-ph/0512601