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Subaru Surveys for High-z Galaxies [article]

Yoshiaki Taniguchi
2003 arXiv   pre-print
Taniguchi) joined to the SDF project. (1) SDF2002: Thirteen nights were allocated to the SDF project in the semester S02A.  ...  Taniguchi) made a survey for Lyα emitters at z ≈ 5.7 based on optical narrowband (λ c = 8150Å and ∆λ = 120Å), and broad-band (B, R C , I C , and z ′ ) obser- vations of the field surrounding the high  ... 
arXiv:astro-ph/0312228v1 fatcat:7gsgkl73hven3batlk3ba3mnby

Why Can We Detect Quasar BR1202-0725 in Co ? [article]

Chisato Ikuta, Nobuo Arimoto, Yoshiaki Sofue, & Yoshiaki Taniguchi
1997 arXiv   pre-print
formation epoch (z > 4) of high-z quasars studied by chemical properties of the broad emission-line regions (Hamann & Ferland 1992 Hill, Thompson, & Elston 1993; Elston et al. 1994; Kawara et al. 1996; Taniguchi  ...  Although the choice of z f is rather arbitrary, z f ≥ 5 has some supports from recent studies on the metallicity of broad emission-line regions of high-z quasars (Hamann & Ferland 1992 Kawara et al. 1996; Taniguchi  ... 
arXiv:astro-ph/9710192v1 fatcat:ovvnebvypngpfos2pii33rze5q

Dusty Tori of Seyfert Nuclei [article]

Yoshiaki Taniguchi, Takashi Murayama, Hideaki Mouri
2000 arXiv   pre-print
1998a,b) , and 3) viewing angle toward dusty tori based on mid-infrared color (Murayama, Mouri, & Taniguchi 2000) .  ...  In addition, it is also known that some Seyfert nuclei have an extended HINER whose size amounts up to ∼ 1 kpc (Golev et al. 1994; Murayama, Taniguchi, & Iwasawa 1998) .  ... 
arXiv:astro-ph/0001452v1 fatcat:uubll6zwebcczjxzqohk7jfule

CO Observations of Arp's Interacting Galaxies [chapter]

Yoshiaki Sofue, Ken-Ichi Wakamatsu, Yoshiaki Taniguchi, Naomasa Nakai, Toshihiro Handa
1991 The Magellanic Clouds  
Starburst galaxies are interacting A number of starburst galaxies are included in the Atlas of Peculiar Galaxies (Αφ 1966) which is the collection of pecuh'ar-morphology galaxies showing mutual tidal interaction. A scenario of starburst can be summarized as follows (e.g. Sofue 1987 , Noguchi 1988. Tidal interaction between galaxies causes an oval disturbance in the gravitational potential of a galaxy. The oval disturbance causes a bar in the innermost region of the galaxy. By this bar a
more » ... this bar a galactic shock wave is excited, which results in rapid accretion of gas toward the central region. The accreted gas produces a dense ring or a core of molecular gas in the central region, from which massive stars are born. Intense UV radiation from the stars heats dust in the dense molecular gas core/ring, and the dust emits strong FIR emission. Does every interacting galaxy show starburst? This scenario seems to have been widely accepted. However, it has been based on the fact that the observed starburst galaxies or FIR luminous galaxies are often identified with interacting galaxies. Namely, the scenario is sample-dependent, where only active star-forming galaxies are taken into account. On the other hand, no systematic study of the behaviour of molecular gas in interacting galaxies, namely dynamics, distribution, and physical condition of the gas, has been made as yet. Some questions arise: is starburst inevitable as a consequence of galaxy-galaxy interaction? If so, in which phase of interaction does a starburst occur? What dynamics, distribution and physical condition does the molecular gas show during interactions? In particular, is the star-formation rate in the central regions higher in interacting systems? To answer these questions, in particular the last one, we have conducted a 12 CO(7 =1-0) line survey of interacting systems in the Arp's atlas. We have obtained spectra for the central regions of 43 galaxies, while no maps have been obtained. Observations were made in the winters of 1989 and 1990, using the 45-m telescope of the Nobeyama Radio Observatory with a HPBW of 17". The total observing time per data point (usually per galaxy) was 1-2 hours, so that the onsource integration time was about 20-40 min. The rms noise of the resultant spectra of 10 km s _1 velocity resolution was about AT mb ~ 10 mK. 485 R. Haynes and D. Milne (eds.), The Magellanic Clouds, 485-486.
doi:10.1007/978-94-011-3432-3_131 fatcat:fipkh323anfm7bhulu2j65zrwu

CO observations of Arp's interacting galaxies

Yoshiaki Sofue, Ken-Ichi Wakamatsu, Yoshiaki Taniguchi, Naomasa Nakai, Toshihiro Handa
1991 Symposium - International astronomical union  
A number of starburst galaxies are included in theAtlas of Peculiar Galaxies(Arp 1966) which is the collection of peculiar-morphology galaxies showing mutual tidal interaction. A scenario of starburst can be summarized as follows (e.g. Sofue 1987, Noguchi 1988). Tidal interaction between galaxies causes an oval disturbance in the gravitational potential of a galaxy. The oval disturbance causes a bar in the innermost region of the galaxy. By this bar a galactic shock wave is excited, which
more » ... xcited, which results in rapid accretion of gas toward the central region. The accreted gas produces a dense ring or a core of molecular gas in the central region, from which massive stars are born. Intense UV radiation from the stars heats dust in the dense molecular gas core/ring, and the dust emits strong FIR emission.
doi:10.1017/s0074180900201241 fatcat:25x5o34pnrgmhgunzbkh7a4bie

The [O III]4363 Emitting Region Obscured by Dusty Tori [article]

Tohru Nagao, Takashi Murayama, Yoshiaki Taniguchi
2001 arXiv   pre-print
& Taniguchi (1998b) .  ...  Then, we compare R Oiii with various parameters to know the nature of the [O iii]λ4363 emitting regions in AGNs (see Nagao, Murayama, & Taniguchi 2001 for more details).  ... 
arXiv:astro-ph/0106295v1 fatcat:4zojhpa46nbljbpapt5tjvxyr4

Circumnuclear molecular gas in Seyfert galaxies

Yoshiaki Taniguchi, Osamu Kameya, Naomasa Nakai, Kimiaki Kawara
1990 Astrophysical Journal  
In order to investigate ci uclear molecular gaseous contents and its relation to the nuclear activity, ade a search for circumnuclear 112C0 ( J = l -0) emission from 28 starbursts galaxies (SBNs) and 12 Seyfert galaxies with the recession velocities less than 5000 kmjs-', using the Nobeyama Radio Observatory 45-m telescope. The full half-power beam width of 17 arcsec covers a region of less than about 5 ameter for the sample galaxies. The circumnuclear CO emission h ected from twelve SBNs (one
more » ... m twelve SBNs (one is summarized .as follows. I. Starburst-Nucleus Galaxies (1) We study a relation between MH~/MHI and [OIII]/HP, where the latter ratio provides a measure of excitation condition of the ionized gas. It is indicated that the galaxies in which the circumnuclear gas is less abundant have higher-excitation emitting regions in general. This implies that molecular gas clouds are dissociated by strong radiation and/or supernova wind activity in such galaxies. Alternatively, we simply interpret that more intense starburst activity tends to h umed more molecular gas. results with previous CO studies made at radio observatories with 1 beam sizes, we investigated the radial distribution of s. We found that most of the SBNs show a tendency of central concentratjon of molecular gas in comparison to Seyfert galaxies. (3) We found tbat two of the SBNs (Mrk 52 and Mrk 708) have very narrow CO line widths although they look like significantly inclined galaxies. This strongly suggests that the circumnuclear molecular gas clouds in these galaxies are kinematically independent from the host galaxies. Since these galaxies have prominent bar structure, it is considered that the bar shock cause forcing gas infall toward the nuclear regions, triggering the nuclear starburst activities. i 1 marginal) and four Seyfert galaxies. Om main results an i 56 https://ntrs.nasa.gov/search.jsp?
doi:10.1086/168967 fatcat:yqd2spxhw5dljexiofo7csrrki

ASCA observation of Henize 2-10

Youichi Ohyama, Yoshiaki Taniguchi
1999 Symposium - International astronomical union  
The contribution of LMXBs would not be 524 Youichi Ohyama, Yoshiaki Taniguchi Table 1.  ...  Introduction Henize2-10 is the prototypical Wolf-Rayet starburst galaxy (Conti 1991; Sugai & Taniguchi 1992 ) at a distance of 8.7Mpc (Stevens & Strickland 1998) .  ... 
doi:10.1017/s0074180900206232 fatcat:lxgpe56wcbg6rifwtq5dcllxru

Position-Velocity Diagrams as a Probe of the Bar in Edge-On Galaxies

Keiichi Wada, Tetsuo Hasegawa, Yoshiaki Sofue, Yoshiaki Taniguchi, Asao Habe
1996 Symposium - International astronomical union  
., Sapporo 060, Japan TETSUO HASEGAWA, YOSHIAKI SOFUE Institute of Astronomy, The Univ. of Tokyo, Mitaka, Tokyo 181, Japan YOSHIAKI TANIGUCHI  ... 
doi:10.1017/s007418090022963x fatcat:pg5dep5xjncgndqooob47hkiwe

A Provocative Summary: Is There Any Unified Model for Triggering Active Galactic Nuclei ? [article]

Yoshiaki Taniguchi
2013 arXiv   pre-print
Here we should remind that the starburst activity also 266 Yoshiaki Taniguchi needs some triggering mechanisms because a lot of dense gas must be accumulated in the nuclear region of galaxies.  ...  ., Taniguchi 2003 Taniguchi , 2004 .  ... 
arXiv:1312.2330v1 fatcat:erja56722fgxdejpgtxftnepji

Poststarburst Models of LINERS

Yoshiaki Taniguchi, Yasuhiro Shioya, Takashi Murayama
2000 Astronomical Journal  
If starbursts were triggered by minor-mergers of satellite galaxies, the morphology of host galaxies could be altered (Mihos & Hernquist 1994; Hernquist & Mihos 1995; Taniguchi & Wada 1996) .  ...  Phase III (2 × 10 7 ∼ < t ∼ < 1 × 10 8 yr): Continuous supernova explosions develop a superwind and then shock heating also works in this phase (Heckman, Armus, & Miley 1990; Ohyama, Taniguchi, & Terlevich  ... 
doi:10.1086/301520 fatcat:eva6qq5zgjfw7cew2nu674smyy

Stress-Fiber Wheel Rotation in Keratocytes

Chika OKIMURA, Atsushi TANIGUCHI, Shigenori NONAKA, Yoshiaki IWADATE
2019 Seibutsu Butsuri  
doi:10.2142/biophys.59.094 fatcat:jk27u2ky65ae3fhyvyqqsq37pq

Position-Velocity Diagrams as a Probe of the Bar in Edge-On Galaxies [chapter]

Keiichi Wada, Tetsuo Hasegawa, Yoshiaki Sofue, Yoshiaki Taniguchi, Asao Habe
1996 Unsolved Problems of the Milky Way  
., Sapporo 060, Japan TETSUO HASEGAWA, YOSHIAKI SOFUE Institute of Astronomy, The Univ. of Tokyo, Mitaka, Tokyo 181, Japan YOSHIAKI TANIGUCHI  ... 
doi:10.1007/978-94-009-1687-6_19 fatcat:gwinikkajffqjk4f2b37iewukm

Discovery of Active Galactic Nuclei in Mid- and Far-Infrared Deep Surveys with ISO [article]

Yoshiaki Taniguchi
2001 arXiv   pre-print
together on the MIR/FIR deep surveys with ISO and their follow-up observations, Len Cowie, Dave Sanders, Bob Joseph, Haruyuki Okuda, Kimiaki Kawara, Yasunori Sato, Toshio Matsumoto, Hideo Matsuhara, Yoshiaki  ...  However, only a few AGN were found in the remaining four surveys (Aussel et al. 1999; Taniguchi 1999 Taniguchi , 2000 Altieri et al. 1999; Fadda et al. 2000) .  ...  ., Pier & Krolik 1992; Clavel et al. 2000; Laurent et al. 2000; Murayama, Mouri, & Taniguchi 2000 and references therein).  ... 
arXiv:astro-ph/0111009v1 fatcat:zjnfqgbp6zemvcajwrj6p2fomy

Subaru surveys for the high-redshift universe

Yoshiaki Taniguchi
2006 Proceedings of the International Astronomical Union  
., Taniguchi et al. 2005; Kashikawa et al. 2006) , and z 7 (Iye et al. 2006; Hu et al. 2007) .  ... 
doi:10.1017/s1743921307010290 fatcat:pijfh337lvembmd6slva4ujaqe
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