- ID:
- ivo://CDS.VizieR/J/A+A/631/A53
- Title:
- 1-D optical spectra for IRAS19135+3937
- Short Name:
- J/A+A/631/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We aim to determine the geometry, density gradient, and velocity structure of jets in post-asymptotic giant branch (post-AGB) binaries. Our high cadence time series of high-resolution optical spectra of jet-creating post-AGB binary systems provide us with a unique tomography of the jet. We determine the spatio-kinematic structure of the jets based on these data by fitting the synthetic spectral line profiles created by our model to the observed, orbital phase-resolved, H{alpha}-line profiles of these systems. The fitting routine is provided with an initial spectrum and is allowed to test three configurations, derived from three specific jet launching models: a stellar jet launched by the star, an X-wind, and a disk wind configuration. We apply a Markov-chain Monte Carlo routine in order to fit our model to the observations. Our fitting code is tested on the post-AGB binary IRAS19135+3937. We find that a model using the stellar jet configuration gives a marginally better fit to our observations. The jet has a wide half-opening angle of about 76 degrees and reaches velocities up to 870km/s. Our methodology is successful in determining some parameters for jets in post-AGB binaries. The model for IRAS19135+3937 includes a transparent, low density inner region (for a half-opening angle <40{deg}). The source feeding the accretion disk around the companion is most likely the circumbinary disk. We will apply this jet fitting routine to other jet-creating post-AGB stars in order to provide a more complete description of these objects. We aim at describing and understanding binary interaction processes in systems with very evolved companions. Here, we focus on understanding the origin and determining the properties of the high-velocity outflow observed in one such system.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/753/42
- Title:
- Double-peaked AGN. I. Dual AGN candidates
- Short Name:
- J/ApJ/753/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Merger-remnant galaxies with kiloparsec (kpc) scale separation dual active galactic nuclei (AGNs) should be widespread as a consequence of galaxy mergers and triggered gas accretion onto supermassive black holes, yet very few dual AGNs have been observed. Galaxies with double-peaked narrow AGN emission lines in the Sloan Digital Sky Survey (SDSS) are plausible dual AGN candidates, but their double-peaked profiles could also be the result of gas kinematics or AGN-driven outflows and jets on small or large scales. To help distinguish between these scenarios, we have obtained spatial profiles of the AGN emission via follow-up long-slit spectroscopy of 81 double-peaked narrow-line AGNs in SDSS at 0.03<=z<=0.36 using Lick, Palomar, and MMT Observatories. We find that all 81 systems exhibit double AGN emission components with ~kpc projected spatial separations on the sky (0.2h^-1^_70_kpc<{Delta}x<5.5h^-1^_70_kpc; median {Delta}x=1.1h^-1^_70_kpc), which suggests that they are produced by kiloparsec-scale dual AGNs or kiloparsec-scale outflows, jets, or rotating gaseous disks.
- ID:
- ivo://CDS.VizieR/J/ApJ/832/67
- Title:
- Double-peaked narrow lines in AGN. II. z<0.1
- Short Name:
- J/ApJ/832/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical long-slit observations of the complete sample of 71 Type 2 active galactic nuclei (AGNs) with double-peaked narrow emission lines at z<0.1 in the Sloan Digital Sky Survey. Double-peaked emission lines are produced by a variety of mechanisms including disk rotation, kiloparsec-scale dual AGNs, and narrow-line region (NLR) kinematics (outflows or inflows). We develop a novel kinematic classification technique to determine the nature of these objects using long-slit spectroscopy alone. We determine that 86% of the double-peaked profiles are produced by moderate-luminosity AGN outflows, 6% are produced by rotation, and 8% are ambiguous. While we are unable to directly identify dual AGNs with long-slit data alone, we explore their potential kinematic classifications with this method. We also find a positive correlation between the NLR size and luminosity of the AGN NLRs (R_NLR_{propto}L_[OIII]_^0.21+/-0.05^), indicating a clumpy two-zone ionization model for the NLR.
- ID:
- ivo://CDS.VizieR/J/ApJ/867/66
- Title:
- Double-peaked narrow lines in AGN. IV. Mergers
- Short Name:
- J/ApJ/867/66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Double-peaked narrow emission lines in active galactic nucleus (AGN) spectra can be produced by AGN outflows, rotation, or dual AGNs, which are AGN pairs in ongoing galaxy mergers. Consequently, double-peaked narrow AGN emission lines are useful tracers of the coevolution of galaxies and their supermassive black holes, as driven by AGN feedback and AGN fueling. We investigate this concept further with follow-up optical longslit observations of a sample of 95 Sloan Digital Sky Survey (SDSS) galaxies that have double-peaked narrow AGN emission lines. Based on a kinematic analysis of the longslit spectra, we confirm previous work that finds that the majority of double-peaked narrow AGN emission lines are associated with outflows. We also find that eight of the galaxies have companion galaxies with line-of-sight velocity separations <500km/s and physical separations <30kpc. Since we find evidence of AGNs in both galaxies, all eight of these systems are compelling dual AGN candidates. Galaxies with double-peaked narrow AGN emission lines occur in such galaxy mergers at least twice as often as typical active galaxies. Finally, we conclude that at least 3% of SDSS galaxies with double-peaked narrow AGN emission lines are found in galaxy mergers where both galaxies are resolved in SDSS imaging.
- ID:
- ivo://CDS.VizieR/J/A+A/590/A93
- Title:
- Doubly ^13^C-substituted ethyl cyanide
- Short Name:
- J/A+A/590/A93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed a spectral line survey called Exploring Molecular Complexity with ALMA (EMoCA) toward Sagittarius B2(N) between 84.1 and 114.4GHz with the Atacama Large Millimeter/submillimeter Array (ALMA) in its Cycles 0 and 1. Line intensities of the main isotopic species of ethyl cyanide and its singly ^13^C-substituted isotopomers observed toward the hot molecular core Sagittarius B2(N2) suggest that the doubly ^13^C-substituted isotopomers should also be detectable. We want to determine the spectroscopic parameters of all three doubly ^13^C-substituted isotopologues of ethyl cyanide to search for them in our ALMA data. We investigated the laboratory rotational spectra of the three species between 150GHz and 990GHz. We searched for emission lines produced by these species in the ALMA spectrum of Sagittarius B2(N2). We modeled their emission and the emission of the ^12^C and singly ^13^C-substituted isotopologues assuming local thermodynamic equilibrium.
- ID:
- ivo://CDS.VizieR/J/A+A/445/857
- Title:
- DPOSS II compact group survey
- Short Name:
- J/A+A/445/857
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the results of a pilot redshift survey of 18 candidate compact groups from the distant DPOSS survey that extends to redshift 0.2 the available surveys of compact groups of galaxies, mainly Hickson Compact Groups and Southern Compact Groups. The goal of our survey was to confirm group membership via redshift information and to measure the characteristic parameters of a representative, albeit small, sample of DPOSS survey groups.
- ID:
- ivo://CDS.VizieR/J/A+A/539/A106
- Title:
- DPOSS II compact group survey. EMMI-NTT sample
- Short Name:
- J/A+A/539/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a redshift survey of 138 candidate compact groups from the DPOSS II catalogue, which extends the available redshift range of spectroscopically confirmed compact groups of galaxies to redshift z~0.2. In this survey, we aim to confirm group membership via spectroscopic redshift information, to measure the characteristic properties of the confirmed groups, namely their mass, radius, luminosity, velocity dispersion, and crossing time, and to compare them with those of nearby compact groups. Using information available from the literature, we also studied the surrounding group environment and searched for additional, previously unknown, group members, or larger scale structures to whom the group might be associated.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/160
- Title:
- 3D spectroscopy in 30 Dor
- Short Name:
- J/ApJS/191/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have completed a new optical imaging and spectrophotometric survey of a 140x80pc^2^ region of 30 Doradus centered on R136, covering key optical diagnostic emission lines including H{alpha}, H{beta}, H{gamma}, [OIII]4363, 4959, 5007, [NII]6548, 6584, [SII]6717, 6731 [SIII]6312, and in some locations [SIII]9069. We present maps of fluxes and intensity ratios for these lines, and catalogs of isolated ionizing stars, elephant-trunk pillars, and edge-on ionization fronts. The final science-quality spectroscopic data products are available to the public. Our analysis of the new data finds that, while stellar winds and supernovae undoubtedly produce shocks and are responsible for shaping the nebula, there are no global spectral signatures to indicate that shocks are currently an important source of ionization. We conclude that the considerable region covered by our survey is well described by photoionization from the central cluster where the ionizing continuum is dominated by the most massive O stars. We show that if 30 Dor were viewed at a cosmological distance, its integrated light would be dominated by its extensive regions of lower surface brightness rather than by the bright, eye-catching arcs.
- ID:
- ivo://CDS.VizieR/J/ApJ/835/208
- Title:
- 2D stellar kinematics of Mrk 1216
- Short Name:
- J/ApJ/835/208
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mrk 1216 is a nearby, early-type galaxy with a small effective radius of 2.8kpc and a large stellar velocity dispersion of 308km/s for its K-band luminosity of 1.4x10^11^L_{sun}_. Using integral field spectroscopy assisted by adaptive optics from Gemini North, we measure spatially resolved stellar kinematics within ~450pc of the galaxy nucleus. The galaxy exhibits regular rotation with velocities of +/-180km/s and a sharply peaked velocity dispersion profile that reaches 425km/s at the center. We fit axisymmetric, orbit-based dynamical models to the combination of these high angular resolution kinematics, large-scale kinematics extending to roughly three effective radii, and Hubble Space Telescope imaging, resulting in a constraint of the mass of the central black hole in Mrk 1216. After exploring several possible sources of systematics that commonly affect stellar-dynamical black hole mass measurements, we find a black hole mass of M_BH_=(4.9+/-1.7)x10^9^M_{sun}_ and an H-band stellar mass-to-light ratio of {Upsilon}_H_=1.3+/-0.4{Upsilon}_{sun}_ (1{sigma} uncertainties). Mrk 1216 is consistent with the local black hole mass-stellar velocity dispersion relation, but is a factor of ~5-10 larger than expectations from the black hole mass-bulge luminosity and black hole mass-bulge mass correlations when conservatively using the galaxy's total luminosity or stellar mass. This behavior is quite similar to the extensively studied compact galaxy NGC 1277. Resembling the z~2 quiescent galaxies, Mrk 1216 may be a passively evolved descendant, and perhaps reflects a previous era when galaxies contained over-massive black holes relative to their bulge luminosities/masses, and the growth of host galaxies had yet to catch up.
- ID:
- ivo://CDS.VizieR/J/A+A/333/658
- Title:
- D-type symbiotic stars emission line fluxes
- Short Name:
- J/A+A/333/658
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of five D-type symbiotics are presented: three oxygen Mira (He2-38, H2-38 and H1-36) and two carbon Mira symbiotics (AS 210 and SS 38). The observations in the spectral range between 3200{AA} and 7400{AA} show the presence of several emission lines in various states of excitation. A line list is provided with their suggested identifications. Several parameters were derived for each object: interstellar reddening as determined from Balmer decrement and He II lines, temperature and electronic density, abundance ratios of Ne/O, Ar/O, Fe/Ne, N/O and He/H. We found nitrogen enrichment while for the other elements their abundances are compatible with solar, except iron which is depleted. We did not detect significant changes in the line and in the continuos spectra of the stars analyzed here, except for He2-38, which increased its degree of excitation compared to Allen's (1984PASAu...5..562N) catalogue.