3D Astrophysics Newsletter

Morpho-kinematic model of the Ant Nebula (Mz 3) generate with SHAPE.

Morpho-kinematic model of the Ant Nebula (Mz 3) generated with SHAPE.

4.1 Today´s new entry:

A morpho-kinematic and spectroscopic study of the bipolar
nebulae: M 2–9, Mz 3, and Hen 2–104

Niall Clyne, Stavros Akras, Wolfgang Steffen, Matthew P. Redman, Denise R. Gonçalves, Eamonn Harvey

Context. Complex bipolar shapes can be generated either as a planetary nebula or symbiotic system. The origin of the material ionised by the white dwarf is very different in these two scenarios and complicates the understanding of the morphologies of planetary nebulae.
Aims. The physical properties, structure, and dynamics of the bipolar nebulae, M 2–9, Mz 3, and Hen 2–104 are investigated in detail with the aim of understanding their nature, shaping mechanisms, and evolutionary history. A morpho-kinematic study, as well as a spectroscopic analysis, can be used to more accurately determine the kinematics and nature of each nebula.
Methods. Long-slit optical echelle spectra are used to investigate the morpho-kinematics of M 2–9, Mz 3, and Hen 2–104. The morpho-kinematic modelling software SHAPE is used to constrain both the morphology and kinematics of each nebula by means of detailed 3-D models. Near-infrared (NIR) data as well as optical spectra are used to separate Galactic symbiotic-type nebulae from genuine planetary nebulae by means of a 2MASS J–H/H–Ks diagram and a 4363/H vs. 5007/H diagnostic diagram, respectively.
Results. The best-fitted 3-D models for M 2–9, Mz 3, and Hen 2–104 provide invaluable kinematical information on the expansion velocity of its nebular components by means of synthetic spectra. The observed spectra match up very well with the synthetic spectra
for each model, thus showing that each model is tightly constrained both morphologically and kinematically. Kinematical ages of the different structures of M 2–9 and Mz 3 have also been determined. Both diagnostic diagrams show M 2–9 and Hen 2–104 to fall well within the category of having a symbiotic source, whereas, Mz 3 borders the region of symbiotic and young planetary nebulae in the optical diagram but is located firmly in the symbiotic region of the NIR colour-colour diagram. The optical diagnostic diagram is shown to successfully separate the two types of nebulae, however, the NIR colour-colour diagram is not as accurate in separating
these objects.
Conclusions. The morphology, kinematics, and evolutionary history of M 2–9, Mz 3, and Hen 2–104 are better understood using the interactive 3-D modelling tool Shape. The expansion velocities of the components for each nebula are better constrained, and fitted with a vector field to reveal their direction of motion. The optical and NIR diagnostic diagrams used are important techniques for separating Galactic symbiotic-type nebulae from genuine planetary nebulae.

Journal: Astronomy & Astrophysics
Comments: 20 pages, 9 figures, 7 tables
Submitted by: W. Steffen


Churi – 3D structure and its dust jets

Bending and formation of jets due to convergence of dust trajectories (left) compared with a Rosetta image of comet "Churi"

Bending and formation of jets due to convergence of dust trajectories (left) compared with a Rosetta image of comet “Churi”

The Rosetta spacecraft has given us unprecedented views of comet “Churi” alias 67P/Churyumov-Gerasimenko. As it gets closer to the sun activity increases and shows many jet-like gas and dust emanations. Usually we associate such jets with regions of locally higher activity, as it was found to be the case in the now famous pits on the comet. However, in a recent paper,  Tobias Kramer et al, (2015) have shown that many of the jets and the overall outflow structure could be a manifestation of the three-dimensional surface structure and the superposition of trajectories from uniformly emitted particles that leave the comet perpendicularly to the local surface. Their method is a beautiful application of “3D-thinking”.  Continue reading

3D Astrophysics Newsletter

Newsletter IllustrationSummary of issue 3:

In May and June we had the following submissions to the 3DA Newsletter:

3.6 FRELLED : A 3D Visualisation Tool For FITS Files
Rhys Taylor,
(Astro-ph) Comment on ‘The role of 3-D interactive visualization in blind surveys of HI in galaxies’ (item 3.3, see below)
URL: http://arxiv.org/abs/1506.04621

3.5 Magnetic Field Structures in Star Forming Regions: Mid-Infrared Imaging Polarimetry of K3-50
Peter Barnes, Dan Li, Charles Telesco, Nahathai Tanakul, Naibi Marinas, Chris Wright, Chris Packham, Eric Pantin, Patrick Roche, James Hough
MNRAS, URL of preprint: http://arxiv.org/abs/1506.02173

3.4 3D-Barolo: a new 3D algorithm to derive rotation curves of galaxies
Di Teodoro, E. M., Fraternali, F.
MNRAS, URL of preprint: http://arxiv.org/abs/1505.07834

3.3 The role of 3-D interactive visualization in blind surveys of HI in galaxies
D. Punzo, J.M. van der Hulst, J.B.T.M. Roerdink, T.A. Oosterloo, M. Ramatsoku, M.A.W. Verheijen
Astronomy and ComputingURL of preprint: http://arxiv.org/abs/1505.06976

3.2 Galaxy Interactions in Compact Groups II: abundance and kinematic anomalies in HCG 91c
F.P.A. Vogt, M.A. Dopita, S. Borthakur, L. Verdes-Montenegro, T.M. Heckman, M.S. Yun, K.C. Chambers
MNRAS, URL of preprint: http://arxiv.org/abs/1504.03337

3.1 Simplified models of stellar wind anatomy for interpreting
high-resolution data
W. Homan, L. Decin, A. de Koter, A.J. van Marle, R. Lombaert, W. Vlemmings
A&A, URL of preprint: http://arxiv.org/pdf/1504.04996v2.pdf