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A 12CO () and () atlas of circumstellar envelopes of AGB and post-AGB stars

to: R. Neri Such a copious mass loss process necessarily leads to substantial changes in the stellar structure and appearance especially when the amount of mass ejecta becomes comparable to the mass of

A 12CO () and () atlas of circumstellar envelopes of AGB and post-AGB stars

to: R. Neri Such a copious mass loss process necessarily leads to substantial changes in the stellar structure and appearance especially when the amount of mass ejecta becomes comparable to the mass of

Structure and dynamics of the molecular gas in M 2–9: a follow-up study with ALMA

Context. M 2–9 is a young planetary nebula (PN) that shows the characteristics of its last ejections in unprecedented detail. These last ejections are thought to trigger the post−asymptotic giant branch evolution.Aims. To assemble an overall picture of how M 2–9 was shaped, we analyzed the characteristics of the different molecular gas components and their relation with the...

High spatial resolution imaging of SO and H2CO in AB Auriga: The first SO image in a transitional disk

Context. Transitional disks are structures of dust and gas around young stars with large inner cavities in which planet formation may occur. Lopsided dust distributions are observed in the dust continuum emission at millimeter wavelengths. These asymmetrical structures can be explained as being the result of an enhanced gas density vortex where the dust is trapped, potentially...

The structure of the Cepheus E protostellar outflow: The jet, the bowshock, and the cavity

Context. Protostellar outflows are a crucial ingredient of the star-formation process. However, the physical conditions in the warm outflowing gas are still poorly known.Aims. We present a multi-transition, high spectral resolution CO study of the outflow of the intermediate-mass Class 0 protostar Cep E-mm. The goal is to determine the structure of the outflow and to constrain...

ACA [CI] observations of the starburst galaxy NGC 253

Context. Carbon monoxide (CO) is widely used as a tracer of the molecular gas in almost all types of environments. However, several shortcomings of CO complicate usaging it as H2 tracer, such as its optical depth effects, the dependence of its abundance on metallicity, or its susceptibility to dissociation in highly irradiated regions. Neutral carbon emission has been proposed to...

SiO collimated outflows driven by high-mass YSOs in G24.78+0.08

, M. 2001 , A &A, 372 , 899 Beltrán , M. T. , Cesaroni , R. , Neri , R. , et al. 2004 , ApJ, 601 , L187 Beltrán , M. T. , Cesaroni , R. , Neri , R. , et al. 2005 , A &A, 435 , 901 Beltrán, M. T ... , C. , Furuya , R. S. , & Testi , L. 2003 , A &A, 401 , 227 Cesaroni, R. , Neri , R. , Olmi , L. , et al. 2005 , A &A, 434 , 1039 Codella, C. , Testi , L. , & Cesaroni , R. 1997 , A &A, 325 , 282

ALMA observations of the Red Rectangle, a preliminary analysis

Aims. We aim to study equatorial disks in rotation and axial outflows in post-AGB objects so as to disclose the formation and shaping mechanisms in planetary nebulae. So far, both disks and outflows have not been observed simultaneously.Methods. We obtained high-quality ALMA observations of 12CO and 13CO J = 3−2 and 12CO J = 6−5 line emission in the Red Rectangle, the only post...

A search for linear polarization in the active galactic nucleus 3C 84 at 239 and 348GHz⋆

We report a search for linear polarization in the active galactic nucleus (AGN) 3C 84 (NGC 1275) at observed frequencies of 239 and 348 GHz, corresponding to rest-frame frequencies of 243 and 354 GHz. We collected polarization data with the IRAM Plateau de Bure Interferometer via Earth rotation polarimetry. We do not detect linear polarization. Our analysis finds 3σ upper limits...

ALMA reveals the feeding of the Seyfert 1 nucleus in NGC 1566

We report ALMA observations of CO(3–2) emission in the Seyfert 1 galaxy NGC 1566, at a spatial resolution of 25 pc. Our aim is to investigate the morphology and dynamics of the gas inside the central kpc, and to probe nuclear fueling and feedback phenomena. NGC 1566 has a nuclear bar of 1.7 kpc radius and a conspicuous grand design spiral starting from this radius. The ALMA field...

Fueling the central engine of radio galaxies - III. Molecular gas and star formation efficiency of 3C 293

Context. Powerful radio galaxies show evidence of ongoing active galactic nuclei (AGN) feedback, mainly in the form of fast, massive outflows. But it is not clear how these outflows affect the star formation of their hosts. Aims. We investigate the different manifestations of AGN feedback in the evolved, powerful radio source 3C 293 and their impact on the molecular gas of its...

ALMA observations of feeding and feedback in nearby Seyfert galaxies: an AGN-driven outflow in NGC 1433

We report ALMA observations of CO(3–2) emission in the Seyfert 2 galaxy NGC 1433 at the unprecedented spatial resolution of 0.′′5 = 24 pc. Our aim is to probe active galactic nucleus (AGN) feeding and feedback phenomena through the morphology and dynamics of the gas inside the central kpc. The galaxy NGC 1433 is a strongly barred spiral with three resonant rings: one at the ultra...

Massive molecular outflows and evidence for AGN feedback from CO observations

We study the properties of massive, galactic-scale outflows of molecular gas and investigate their impact on galaxy evolution. We present new IRAM PdBI CO(1–0) observations of local ultra-luminous infrared galaxies (ULIRGs) and quasar-hosts: a clear signature of massive and energetic molecular outflows, extending on kpc scales, is found in the CO(1–0) kinematics of four out of...

Detection of HCN, HCO+, and HNC in the Mrk 231 molecular outflow - Dense molecular gas in the AGN wind

Aims. Our goal is to study gas properties in large-scale molecular outflows and winds from active galactic nuclei (AGNs) and starburst galaxies.Methods. We obtained high-resolution (1.

Fueling the central engine of radio galaxies - II. The footprints of AGN feedback on the ISM of 3C 236

Context. There is growing observational evidence of active galactic nuclei (AGN) feedback on the interstellar medium (ISM) of radio-quiet and radio-loud galaxies. While AGN feedback is expected to be more common at high-redshift objects, studying local universe galaxies helps to better characterize the different manifestations of AGN feedback.Aims. Molecular line observations can...

Dust properties of protoplanetary disks in the Taurus-Auriga star forming region from millimeter wavelengths

We present the most sensitive 3 mm-survey to date of protoplanetary disks carried out in the Taurus-Auriga star forming region (average rms of about 0.3 mJy), using the IRAM PdBI. With our high detection rate of 17/19 we provide the first detections at wavelengths longer than about 1 mm for 12 sources. This enables us to statistically study the mm SED slopes and dust properties...

Variations in the fundamental constants in the QSO host J1148+5251 at z = 6.4 and the BR1202−0725 system at z = 4.7

. , Combes F. , 2006 , A&A, 453 , 77 Salome P. , Guelin M. , Downes D. , Cox P. , Guilloteau S. , Omont A. , Gavazzi R. , Neri R. , 2012 , A&A, 545 , A57 Stacey G. J. , Geis N. , Genzel R. , Lugten J. B

Molecular gas chemistry in AGN - II. High-resolution imaging of SiO emission in NGC 1068: shocks or XDR?

Context. This paper is part of a multi-species survey of line emission from the molecular gas in the circum-nuclear disk (CND) of the Seyfert 2 galaxy NGC 1068. Unlike in other active galaxies, the intensely star-forming regions in NGC 1068 and the CND can be resolved with current instrumentation. This makes this galaxy an optimal test-bed to probe the effects of AGN on the...