Achievements & Publications

L483: Warm Carbon-chain Chemistry Source Harboring Hot Corino Activity

Image

Oya, Yoko,   Sakai, Nami,   Watanabe, Yoshimasa,   Higuchi, Aya E.,   Hirota, Tomoya,   López-Sepulcre, Ana

The Class 0 protostar, L483, has been observed in various molecular lines in the 1.2 mm band at a subarcsecond resolution with ALMA. An infalling-rotating envelope is traced by the CS line, while a very compact component with a broad velocity width is observed for the CS, SO, HNCO, NH$_2$CHO,...

Effects of Grain Growth on Molecular Abundances in Young Stellar Objects

Image

Harada, Nanase,   Hasegawa, Yasuhiro,   Aikawa, Yuri,   Hirashita, Hiroyuki,   Liu, Haoyu Baobab,   Hirano, Naomi

Recent observations suggested that the growth of dust grains may have already occurred in class 0/I young stellar objects (YSOs). Since chemical reactions on dust grain surfaces are important in determining molecular abundances, the dust size growth may affect chemical compositions in YSOs significantly. In this work, we aim to...

Water delivery from cores to disks: Deuteration as a probe of the prestellar inheritance of H$_2$O

Image

Furuya, K.,   Drozdovskaya, M.~N.,   Visser, R.,   van Dishoeck, E.~F.,   Walsh, C.,   Harsono, D.

We investigate the delivery of regular and deuterated forms of water from prestellar cores to circumstellar disks. We adopt a semi- analytical, axisymmetric, two-dimensional collapsing core model with post-processing gas-ice astrochemical simulations, in which a layered ice structure is considered. The physical and chemical evolutions are followed until the end...

ALMA Reveals Strong [C II] Emission in a Galaxy Embedded in a Giant Ly\ensuremathα Blob at z = 3.1

Image

Umehata, Hideki,   Matsuda, Yuichi,   Tamura, Yoichi,   Kohno, Kotaro,   Smail, Ian,   Ivison, R.~J.

We report the result from observations conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) to detect [C II] 158 \ensuremathμm fine structure line emission from galaxies embedded in one of the most spectacular Ly\ensuremathα blobs (LABs) at z = 3.1, SSA22-LAB1. Of three dusty star-forming galaxies previously discovered by ALMA...

Outflows driven by quasars in high-redshift galaxies with radiation hydrodynamics

Image

Bieri, Rebekka,   Dubois, Yohan,   Rosdahl, Joakim,   Wagner, Alexander,   Silk, Joseph,   Mamon, Gary A.

The quasar mode of active galactic nuclei (AGN) in the high-redshift Universe is routinely observed in gas-rich galaxies together with large-scale AGN-driven winds. It is crucial to understand how photons emitted by the central AGN source couple to the ambient interstellar medium to trigger large-scale outflows. By means of radiation-hydrodynamical...

Following the Interstellar History of Carbon: From the Interiors of Stars to the Surfaces of Planets

Image

Ziurys, L.~M.,   Halfen, D.~T.,   Geppert, W.,   Aikawa, Y.

The chemical history of carbon is traced from its origin in stellar nucleosynthesis to its delivery to planet surfaces. The molecular carriers of this element are examined at each stage in the cycling of interstellar organic material and their eventual incorporation into solar system bodies. The connection between the various...

Cosmology with the Square Kilometre Array by SKA-Japan

Image

Yamauchi, Daisuke,   Ichiki, Kiyotomo,   Kohri, Kazunori,   Namikawa, Toshiya,   Oyama, Yoshihiko,   Sekiguchi, Toyokazu

In the past several decades, the standard cosmological model has been established and its parameters have been measured to a high precision, while there are still many fundamental questions in cosmology; such as the physics in the very early universe, the origin of the cosmic acceleration, and the nature of...

ALMA Reveals the Anatomy of the mm-sized Dust and Molecular Gas in the HD 97048 Disk

Image

Walsh, Catherine,   Juhász, Attila,   Meeus, Gwendolyn,   Dent, William R.~F.,   Maud, Luke T.,   Aikawa, Yuri

Transitional disks show a lack of excess emission at infrared wavelengths due to a large dust cavity, that is often corroborated by spatially resolved observations at ̃ mm wavelengths. We present the first spatially resolved ̃ mm- wavelength images of the disk around the Herbig Ae/Be star, HD 97048. Scattered...

Spectral Line Survey toward a Molecular Cloud in IC10

Image

Nishimura, Yuri,   Shimonishi, Takashi,   Watanabe, Yoshimasa,   Sakai, Nami,   Aikawa, Yuri,   Kawamura, Akiko

We have conducted a spectral line survey observation in the 3 mm band toward the low-metallicity dwarf galaxy IC10 with the 45 m radio telescope of the Nobeyama Radio Observatory to explore its chemical composition at a molecular-cloud scale (\ensuremath∼80 pc). The CS, SO, CCH, HCN, HCO$^+$, and HNC lines...

The Sunyaev-Zel'dovich effect at 5″: RX J1347.5-1145 imaged by ALMA

Image

Kitayama, Tetsu,   Ueda, Shutaro,   Takakuwa, Shigehisa,   Tsutsumi, Takahiro,   Komatsu, Eiichiro,   Akahori, Takuya

We present the first image of the thermal Sunyaev-Zel'dovich effect (SZE) obtained by the Atacama Large Millimeter/submillimeter Array (ALMA). Combining 7-m and 12-m arrays in Band 3, we create an SZE map toward a galaxy cluster RX J1347.5-1145 with 5″ resolution (corresponding to a physical size of 20 h$^-1$ kpc),...

Discovery of a Hot Corino in the Bok Globule B335

Image

Imai, Muneaki,   Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Ceccarelli, Cecilia

We report the first evidence of a hot corino in a Bok globule. This is based on ALMA observations in the 1.2 mm band toward the low- mass Class 0 protostar IRAS 19347+0727 in B335. Saturated complex organic molecules (COMs), CH$_3$CHO, HCOOCH$_3$, and NH$_2$CHO, are detected in a compact region...

Collision Tomography: Physical Properties of Possible Progenitors of the Andromeda Stellar Stream

Image

Miki, Yohei,   Mori, Masao,   Rich, R. Michael

To unveil a progenitor of the Andromeda Giant Stellar Stream, we investigate the interaction between an accreting satellite galaxy and the Andromeda Galaxy using an N-body simulation. We perform a comprehensive exploration of the properties of the progenitor dwarf galaxy, using 247 models of varying mass, mass distribution, and size....

Sub-parsec-scale dynamics of a dusty gas disc exposed to anisotropic AGN radiation with frequency-dependent radiative transfer

Image

Namekata, Daisuke,   Umemura, Masayuki

We explore the gas dynamics near the dust sublimation radius of active galactic nucleus (AGN). For the purpose, we perform axisymmetric radiation hydrodynamic simulations of a dusty gas disc of radius \ensuremath≈1 pc around a supermassive black hole of mass 10$^7$ M$_☉$ taking into account (1) anisotropic radiation of accretion...

First Detection of Gas-phase Methanol in a Protoplanetary Disk

Image

Walsh, Catherine,   Loomis, Ryan A.,   Öberg, Karin I.,   Kama, Mihkel,   van 't Hoff, Merel L.~R.,   Millar, Tom J.

The first detection of gas-phase methanol in a protoplanetary disk (TW Hya) is presented. In addition to being one of the largest molecules detected in disks to date, methanol is also the first disk organic molecule with an unambiguous ice chemistry origin. The stacked methanol emission, as observed with the...

Jet-intracluster medium interaction in Hydra A - II. The effect of jet precession

Image

Nawaz, M.~A.,   Bicknell, G.~V.,   Wagner, A.~Y.,   Sutherland , R.~S.,   McNamara, B.~R.

We present three-dimensional relativistic hydrodynamical simulations of a precessing jet interacting with the intracluster medium and compare the simulated jet structure with the observed structure of the Hydra A northern jet. For the simulations, we use jet parameters obtained in the parameter space study of the first paper in this...

Subarcsecond Analysis of the Infalling-Rotating Envelope around the Class I Protostar IRAS 04365+2535

Image

Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Sakai, Takeshi,   Hirota, Tomoya

Subarcsecond images of the rotational line emission of CS and SO have been obtained toward the Class I protostar IRAS 04365+2535 in TMC-1A with ALMA. A compact component around the protostar is clearly detected in the CS and SO emission. The velocity structure of the compact component of CS reveals...

Statistical properties of diffuse Ly\ensuremathα haloes around star-forming galaxies at z ̃ 2

Image

Momose, Rieko,   Ouchi, Masami,   Nakajima, Kimihiko,   Ono, Yoshiaki,   Shibuya, Takatoshi,   Shimasaku, Kazuhiro

We present statistical properties of diffuse Ly\ensuremathα haloes (LAHs) around high-z star-forming galaxies with large Subaru samples of Ly\ensuremathα emitters (LAEs) at z = 2.2. We make subsamples defined by the physical quantities of LAEs' central Ly\ensuremathα luminosities, ultraviolet (UV) magnitudes, Ly\ensuremathα equivalent widths, and UV slopes, and investigate LAHs'...

Image

L483: Warm Carbon-chain Chemistry Source Harboring Hot Corino Activity

Oya, Yoko,   Sakai, Nami,   Watanabe, Yoshimasa,   Higuchi, Aya E.,   Hirota, Tomoya,   López-Sepulcre, Ana

The Class 0 protostar, L483, has been observed in various molecular lines in the 1.2 mm band at a subarcsecond resolution with ALMA. An infalling-rotating envelope is traced by the CS line, while a very compact component with a broad velocity width is observed for the CS, SO, HNCO, NH$_2$CHO,...

March 2017   The Astrophysical Journal
Image

Effects of Grain Growth on Molecular Abundances in Young Stellar Objects

Harada, Nanase,   Hasegawa, Yasuhiro,   Aikawa, Yuri,   Hirashita, Hiroyuki,   Liu, Haoyu Baobab,   Hirano, Naomi

Recent observations suggested that the growth of dust grains may have already occurred in class 0/I young stellar objects (YSOs). Since chemical reactions on dust grain surfaces are important in determining molecular abundances, the dust size growth may affect chemical compositions in YSOs significantly. In this work, we aim to...

March 2017   The Astrophysical Journal
Image

Water delivery from cores to disks: Deuteration as a probe of the prestellar inheritance of H$_2$O

Furuya, K.,   Drozdovskaya, M.~N.,   Visser, R.,   van Dishoeck, E.~F.,   Walsh, C.,   Harsono, D.

We investigate the delivery of regular and deuterated forms of water from prestellar cores to circumstellar disks. We adopt a semi- analytical, axisymmetric, two-dimensional collapsing core model with post-processing gas-ice astrochemical simulations, in which a layered ice structure is considered. The physical and chemical evolutions are followed until the end...

March 2017  
Image

ALMA Reveals Strong [C II] Emission in a Galaxy Embedded in a Giant Ly\ensuremathα Blob at z = 3.1

Umehata, Hideki,   Matsuda, Yuichi,   Tamura, Yoichi,   Kohno, Kotaro,   Smail, Ian,   Ivison, R.~J.

We report the result from observations conducted with the Atacama Large Millimeter/submillimeter Array (ALMA) to detect [C II] 158 \ensuremathμm fine structure line emission from galaxies embedded in one of the most spectacular Ly\ensuremathα blobs (LABs) at z = 3.1, SSA22-LAB1. Of three dusty star-forming galaxies previously discovered by ALMA...

January 2017   The Astrophysical Journal Letters
Image

Outflows driven by quasars in high-redshift galaxies with radiation hydrodynamics

Bieri, Rebekka,   Dubois, Yohan,   Rosdahl, Joakim,   Wagner, Alexander,   Silk, Joseph,   Mamon, Gary A.

The quasar mode of active galactic nuclei (AGN) in the high-redshift Universe is routinely observed in gas-rich galaxies together with large-scale AGN-driven winds. It is crucial to understand how photons emitted by the central AGN source couple to the ambient interstellar medium to trigger large-scale outflows. By means of radiation-hydrodynamical...

January 2017   Monthly Notices of the Royal Astronomical Society
Image

Following the Interstellar History of Carbon: From the Interiors of Stars to the Surfaces of Planets

Ziurys, L.~M.,   Halfen, D.~T.,   Geppert, W.,   Aikawa, Y.

The chemical history of carbon is traced from its origin in stellar nucleosynthesis to its delivery to planet surfaces. The molecular carriers of this element are examined at each stage in the cycling of interstellar organic material and their eventual incorporation into solar system bodies. The connection between the various...

December 2016  
Image

Cosmology with the Square Kilometre Array by SKA-Japan

Yamauchi, Daisuke,   Ichiki, Kiyotomo,   Kohri, Kazunori,   Namikawa, Toshiya,   Oyama, Yoshihiko,   Sekiguchi, Toyokazu

In the past several decades, the standard cosmological model has been established and its parameters have been measured to a high precision, while there are still many fundamental questions in cosmology; such as the physics in the very early universe, the origin of the cosmic acceleration, and the nature of...

December 2016   Publications of the Astronomical Society of Japan
Image

ALMA Reveals the Anatomy of the mm-sized Dust and Molecular Gas in the HD 97048 Disk

Walsh, Catherine,   Juhász, Attila,   Meeus, Gwendolyn,   Dent, William R.~F.,   Maud, Luke T.,   Aikawa, Yuri

Transitional disks show a lack of excess emission at infrared wavelengths due to a large dust cavity, that is often corroborated by spatially resolved observations at ̃ mm wavelengths. We present the first spatially resolved ̃ mm- wavelength images of the disk around the Herbig Ae/Be star, HD 97048. Scattered...

November 2016   The Astrophysical Journal
Image

Spectral Line Survey toward a Molecular Cloud in IC10

Nishimura, Yuri,   Shimonishi, Takashi,   Watanabe, Yoshimasa,   Sakai, Nami,   Aikawa, Yuri,   Kawamura, Akiko

We have conducted a spectral line survey observation in the 3 mm band toward the low-metallicity dwarf galaxy IC10 with the 45 m radio telescope of the Nobeyama Radio Observatory to explore its chemical composition at a molecular-cloud scale (\ensuremath∼80 pc). The CS, SO, CCH, HCN, HCO$^+$, and HNC lines...

October 2016   The Astrophysical Journal
Image

The Sunyaev-Zel'dovich effect at 5″: RX J1347.5-1145 imaged by ALMA

Kitayama, Tetsu,   Ueda, Shutaro,   Takakuwa, Shigehisa,   Tsutsumi, Takahiro,   Komatsu, Eiichiro,   Akahori, Takuya

We present the first image of the thermal Sunyaev-Zel'dovich effect (SZE) obtained by the Atacama Large Millimeter/submillimeter Array (ALMA). Combining 7-m and 12-m arrays in Band 3, we create an SZE map toward a galaxy cluster RX J1347.5-1145 with 5″ resolution (corresponding to a physical size of 20 h$^-1$ kpc),...

October 2016   Publications of the Astronomical Society of Japan
Image

Discovery of a Hot Corino in the Bok Globule B335

Imai, Muneaki,   Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Ceccarelli, Cecilia

We report the first evidence of a hot corino in a Bok globule. This is based on ALMA observations in the 1.2 mm band toward the low- mass Class 0 protostar IRAS 19347+0727 in B335. Saturated complex organic molecules (COMs), CH$_3$CHO, HCOOCH$_3$, and NH$_2$CHO, are detected in a compact region...

October 2016   The Astrophysical Journal Letters
Image

Collision Tomography: Physical Properties of Possible Progenitors of the Andromeda Stellar Stream

Miki, Yohei,   Mori, Masao,   Rich, R. Michael

To unveil a progenitor of the Andromeda Giant Stellar Stream, we investigate the interaction between an accreting satellite galaxy and the Andromeda Galaxy using an N-body simulation. We perform a comprehensive exploration of the properties of the progenitor dwarf galaxy, using 247 models of varying mass, mass distribution, and size....

August 2016   The Astrophysical Journal
Image

Sub-parsec-scale dynamics of a dusty gas disc exposed to anisotropic AGN radiation with frequency-dependent radiative transfer

Namekata, Daisuke,   Umemura, Masayuki

We explore the gas dynamics near the dust sublimation radius of active galactic nucleus (AGN). For the purpose, we perform axisymmetric radiation hydrodynamic simulations of a dusty gas disc of radius \ensuremath≈1 pc around a supermassive black hole of mass 10$^7$ M$_☉$ taking into account (1) anisotropic radiation of accretion...

July 2016   Monthly Notices of the Royal Astronomical Society
Image

First Detection of Gas-phase Methanol in a Protoplanetary Disk

Walsh, Catherine,   Loomis, Ryan A.,   Öberg, Karin I.,   Kama, Mihkel,   van 't Hoff, Merel L.~R.,   Millar, Tom J.

The first detection of gas-phase methanol in a protoplanetary disk (TW Hya) is presented. In addition to being one of the largest molecules detected in disks to date, methanol is also the first disk organic molecule with an unambiguous ice chemistry origin. The stacked methanol emission, as observed with the...

May 2016   The Astrophysical Journal Letters
Image

Jet-intracluster medium interaction in Hydra A - II. The effect of jet precession

Nawaz, M.~A.,   Bicknell, G.~V.,   Wagner, A.~Y.,   Sutherland , R.~S.,   McNamara, B.~R.

We present three-dimensional relativistic hydrodynamical simulations of a precessing jet interacting with the intracluster medium and compare the simulated jet structure with the observed structure of the Hydra A northern jet. For the simulations, we use jet parameters obtained in the parameter space study of the first paper in this...

May 2016   Monthly Notices of the Royal Astronomical Society
Image

Subarcsecond Analysis of the Infalling-Rotating Envelope around the Class I Protostar IRAS 04365+2535

Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Sakai, Takeshi,   Hirota, Tomoya

Subarcsecond images of the rotational line emission of CS and SO have been obtained toward the Class I protostar IRAS 04365+2535 in TMC-1A with ALMA. A compact component around the protostar is clearly detected in the CS and SO emission. The velocity structure of the compact component of CS reveals...

April 2016   The Astrophysical Journal Letters
Image

Statistical properties of diffuse Ly\ensuremathα haloes around star-forming galaxies at z ̃ 2

Momose, Rieko,   Ouchi, Masami,   Nakajima, Kimihiko,   Ono, Yoshiaki,   Shibuya, Takatoshi,   Shimasaku, Kazuhiro

We present statistical properties of diffuse Ly\ensuremathα haloes (LAHs) around high-z star-forming galaxies with large Subaru samples of Ly\ensuremathα emitters (LAEs) at z = 2.2. We make subsamples defined by the physical quantities of LAEs' central Ly\ensuremathα luminosities, ultraviolet (UV) magnitudes, Ly\ensuremathα equivalent widths, and UV slopes, and investigate LAHs'...

April 2016   Monthly Notices of the Royal Astronomical Society

L483: Warm Carbon-chain Chemistry Source Harboring Hot Corino Activity

Oya, Yoko,   Sakai, Nami,   Watanabe, Yoshimasa,   Higuchi, Aya E.,   Hirota, Tomoya,   López-Sepulcre, Ana
March 2017   The Astrophysical Journal

Effects of Grain Growth on Molecular Abundances in Young Stellar Objects

Harada, Nanase,   Hasegawa, Yasuhiro,   Aikawa, Yuri,   Hirashita, Hiroyuki,   Liu, Haoyu Baobab,   Hirano, Naomi
March 2017   The Astrophysical Journal

Water delivery from cores to disks: Deuteration as a probe of the prestellar inheritance of H$_2$O

Furuya, K.,   Drozdovskaya, M.~N.,   Visser, R.,   van Dishoeck, E.~F.,   Walsh, C.,   Harsono, D.
March 2017  

ALMA Reveals Strong [C II] Emission in a Galaxy Embedded in a Giant Ly\ensuremathα Blob at z = 3.1

Umehata, Hideki,   Matsuda, Yuichi,   Tamura, Yoichi,   Kohno, Kotaro,   Smail, Ian,   Ivison, R.~J.
January 2017   The Astrophysical Journal Letters

Outflows driven by quasars in high-redshift galaxies with radiation hydrodynamics

Bieri, Rebekka,   Dubois, Yohan,   Rosdahl, Joakim,   Wagner, Alexander,   Silk, Joseph,   Mamon, Gary A.
January 2017   Monthly Notices of the Royal Astronomical Society

Following the Interstellar History of Carbon: From the Interiors of Stars to the Surfaces of Planets

Ziurys, L.~M.,   Halfen, D.~T.,   Geppert, W.,   Aikawa, Y.
December 2016  

Cosmology with the Square Kilometre Array by SKA-Japan

Yamauchi, Daisuke,   Ichiki, Kiyotomo,   Kohri, Kazunori,   Namikawa, Toshiya,   Oyama, Yoshihiko,   Sekiguchi, Toyokazu
December 2016   Publications of the Astronomical Society of Japan

ALMA Reveals the Anatomy of the mm-sized Dust and Molecular Gas in the HD 97048 Disk

Walsh, Catherine,   Juhász, Attila,   Meeus, Gwendolyn,   Dent, William R.~F.,   Maud, Luke T.,   Aikawa, Yuri
November 2016   The Astrophysical Journal

Spectral Line Survey toward a Molecular Cloud in IC10

Nishimura, Yuri,   Shimonishi, Takashi,   Watanabe, Yoshimasa,   Sakai, Nami,   Aikawa, Yuri,   Kawamura, Akiko
October 2016   The Astrophysical Journal

The Sunyaev-Zel'dovich effect at 5″: RX J1347.5-1145 imaged by ALMA

Kitayama, Tetsu,   Ueda, Shutaro,   Takakuwa, Shigehisa,   Tsutsumi, Takahiro,   Komatsu, Eiichiro,   Akahori, Takuya
October 2016   Publications of the Astronomical Society of Japan

Discovery of a Hot Corino in the Bok Globule B335

Imai, Muneaki,   Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Ceccarelli, Cecilia
October 2016   The Astrophysical Journal Letters

Collision Tomography: Physical Properties of Possible Progenitors of the Andromeda Stellar Stream

Miki, Yohei,   Mori, Masao,   Rich, R. Michael
August 2016   The Astrophysical Journal

Sub-parsec-scale dynamics of a dusty gas disc exposed to anisotropic AGN radiation with frequency-dependent radiative transfer

Namekata, Daisuke,   Umemura, Masayuki
July 2016   Monthly Notices of the Royal Astronomical Society

First Detection of Gas-phase Methanol in a Protoplanetary Disk

Walsh, Catherine,   Loomis, Ryan A.,   Öberg, Karin I.,   Kama, Mihkel,   van 't Hoff, Merel L.~R.,   Millar, Tom J.
May 2016   The Astrophysical Journal Letters

Jet-intracluster medium interaction in Hydra A - II. The effect of jet precession

Nawaz, M.~A.,   Bicknell, G.~V.,   Wagner, A.~Y.,   Sutherland , R.~S.,   McNamara, B.~R.
May 2016   Monthly Notices of the Royal Astronomical Society

Subarcsecond Analysis of the Infalling-Rotating Envelope around the Class I Protostar IRAS 04365+2535

Sakai, Nami,   Oya, Yoko,   López-Sepulcre, Ana,   Watanabe, Yoshimasa,   Sakai, Takeshi,   Hirota, Tomoya
April 2016   The Astrophysical Journal Letters

Statistical properties of diffuse Ly\ensuremathα haloes around star-forming galaxies at z ̃ 2

Momose, Rieko,   Ouchi, Masami,   Nakajima, Kimihiko,   Ono, Yoshiaki,   Shibuya, Takatoshi,   Shimasaku, Kazuhiro
April 2016   Monthly Notices of the Royal Astronomical Society