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CRL 618 paper Figures

Dennis et al.: http://adsabs.harvard.edu/abs/2008ApJ...679.1327D

New site with info for the paper: https://clover.pas.rochester.edu/trac/astrobear/blog/crl2013

17 dec

Short AGB rings separation, v_bullet=300km/s model, inclination angle of 30^o

TESTS Integrated "Doppler-shift" image. This is the bullet model at 200yr, 30^o inclination angle, and only velocities from 10-50 km/s are mapped (based on a phone discussion with Bruce; I could map any other vel components if wanted).
Ditto with the "red-blue" Shape table.

Time [yr]	50	100	200
non-integrated density maps [part cm^-3] and velocity field comparison Logarithmic false gray-scale density maps and color velocity field on the plane at the middle of the computational domain. Left panels show the bullet model, while right panels show the jet model. The bullet/jet are the densest, whitest, central features. Behind the bullet, or to the right of the jet (without loss of generality), we see the cavity formed by the bullet/jet, which is separated from the ambient medium by a contact discontinuity. The ambient medium is stratified and shows a series of concentric spherical shells (see Section "Initial conditions"). The vertical short red, or blue, lines at the top of the maps show the positions at which the lineouts of Figures X Y have been taken. The bullet and the jet propagate at 300km/s away from the ambient medium's densest region (up), forming an elongated lobe. Comparing the left and the right panels in FIGURE X [gray-scale density maps], we find that the lobes formed by the bullet and the jet are quite similar. As the bullet (jet) penetrates the ambient's shells, these form regularly separated vertebrae-looking features along the lobe. The axial velocity of these features decreases with radial distance from the axis.
non-integrated density lineouts [part cm^-3] comparison. See top row for lineouts' positions.
non-integrated vel. lineouts comparison. See top row for lineouts' positions.
Cooling emission, slit marked in blue, Bullet
Cooling emission, slit marked in blue, Jet
PV diagrams, Bullet
PV diagrams, Jet

5 Dec 2012, long AGB rings separation, v_bullet=200km/s model

Time [yr]	50	100	200
non-integrated density maps [part cm^-3] comparison
integrated Emission & non-integrated vel. comparison
non-integrated density lineouts [part cm^-3] comparison. See top row for lineouts' positions.
non-integrated vel. lineouts comparison. See top row for lineouts' positions.

2 Apr '12

Clump/Jet to ambient density contrast of 100 (was 50)
Toroidal AGB wind, based in Frank & Mellema '94, alpha=.7 and beta=.8
Higher initial densities
128x128x192+2AMR levels (~4 days to run in 1024 bgene procs)

Integrated emission and 2D-middle-plane velocity field	MOVIES
Jet + ambient shells	http://www.pas.rochester.edu/~martinhe/2011/crl/jet-2d-vel-n-INTemiss.gif
Jet + No ambient shells	http://www.pas.rochester.edu/~martinhe/2011/crl/jet-2d-vel-n-INTemiss2.gif

There are some spurious numerical artifacts ahed of the jets' head at late times.

16 mar '12

Clump + ambient shells	MOVIES
High res, 2d DM cooling integrated and velocity field.	http://www.pas.rochester.edu/~martinhe/2011/crl/vel-n-INTemiss.gif
High res, 2d DM cooling not integrated and velocity field.	http://www.pas.rochester.edu/~martinhe/2011/crl/2d-vel-n-emiss.gif
High res, 2d log density, temp and DM cooling not integrated.	http://www.pas.rochester.edu/~martinhe/2011/crl/2d-3parts.gif

Clump + NO ambient shells	MOVIES
Hig res, 2d DM cooling integrated and velocity field.	http://www.pas.rochester.edu/~martinhe/2011/crl/2d-vel-n-INTemiss2.gif
High res, 2d DM cooling not integrated and velocity field.	http://www.pas.rochester.edu/~martinhe/2011/crl/2d-vel-n-emiss2.gif
High res, 2d log density, temp and DM cooling not integrated	http://www.pas.rochester.edu/~martinhe/2011/crl/2d-3parts2.gif

14 feb '12

Clump/jet velocity of 400 km s^-1, dens_clump/dens_amb=50, larger grid.

Lineouts are taken along the lines marked in this figure >

http://www.pas.rochester.edu/~martinhe/2011/crl/clump-ring-64-l.png

Clump, stratified and ringed ambient medium:	t=88yr	t=176yr	t=247yr
Log(dens) maps. MOVIE: http://www.pas.rochester.edu/~martinhe/2011/crl/clump-ring-dens.gif
Log(dens) axial lineouts
Axial vel lineouts

Clump, stratified ambient medium:	t=88yr	t=176yr	t=247yr
Log(dens) maps. MOVIE: http://www.pas.rochester.edu/~martinhe/2011/crl/clump-dens.gif
Log(dens) axial lineouts
Axial vel lineouts

Jet, stratified and ringed ambient medium:	t=88yr	t=176yr	t=247yr
Log(dens) maps. MOVIE: http://www.pas.rochester.edu/~martinhe/2011/crl/jet-ring-dens.gif
Log(dens) axial lineouts
Axial vel lineouts

Jet, stratified ambient medium:	t=88yr	coming soon	ditto
Log(dens) maps. MOVIE: http://www.pas.rochester.edu/~martinhe/2011/crl/jet-dens.gif
Log(dens) axial lineouts
Axial vel lineouts

SYNTHETIC IMAGES

Ambient =r^-2 + rings, time~176yr, the slit is r_jet/2 displaced from the symmetry axis

Inclination	Clump, log(rho²)	Clump, pv		Jet, log(rho²)	Jet, pv
90^o
60^o

Ambient =r^-2, time~176yr for the clump and time~88yr for the jet (still running), the slit is r_jet/2 displaced from the symmetry axis

Inclination	Clump, log(rho²)	Clump, pv		Jet, log(rho²)	Jet, pv
90^o
60^o

Bruce's thoughts

RED IS SHOCK-EXCITED [NII] GREEN IS HALPHA — MOSTLY COMING FROM THE STAR BLUE IS MOSTLY SCATTERED STARLIGHT ============== CO observations regarding the ambient medium

take a look at Fog 2 and the rest of Sa ́nchez Contreras, C., Sahai, R., & Gil de Paz, A. 2002, ApJ, 578, 269 (optical emission-line study of CRL618): http://iopscience.iop.org/0004-637X/578/1/269/pdf/55888.web.pdf)

Here's my summary of the highlights of this paper

Fig 2 shows long-slit P-V diagrams of selected emission lines. Scattered stellar Halpha is significant near the center, and the Halpha line is thermally broadened everywhere. The other lines show a linear rise in V with slit position from the star…close to a Hubble flow. But the lines don't arise from the insides of the fingers. They come from an outer sheath where the lateral expansion of the fingers produce shocks. (Inclination corrections are important in the interpretation of these spectra.) (Note: one might expect two velocity components at each position arising from the near and far sides of the laterally expanding fingers. This isn't seen, but the limited dispersion of the spectrograph could be the reason why. Our models need only explain the general trends of the P-V diagrams.

The optical fingers are relatively low- and constant-density outflows (~5000 cm-3) plowing through a denser and slower AGB wind (10^{6 cm-3; 18 km/s). The density of the AGB wind appears to decline as r}-2. The shock temperatures (shock speed) derived from emission lines range from 10,000 to 25,000K (75-200 km/s). (They do not directly measure the temperatures along the fingers and through the tips using emission line diagnostics such as [NII]5755/6584.)

The optical emission in the fingers consist of (1) scattered starlight, (2) scattered Halpha and other emission lines (e.g. [OIII]) from a small, dense (10^{6 cm-3, T~14000K) HII region within 0."4 of the core, and (3) shocked gas at the interfaces along the edges and at the tips of the fingers. (Scattered light from the HII region is seen inside the lobes but at different velocities than the intrinsic emission from the lobes.)}

The shock speeds needed to explain the observed emission-line ratios are 75-200 km/s. An independent measure of v_shock at the fingers tips comes from the width of emission lines at the tips of the fingers: 200-230 km/s. The shocks can cross the fingers laterally in a few years.

The inclination angle of the fingers is 24 ± 6 deg, so the predicted space motions of the tips are 80/tan24 = 180 km/s, in good agreement with the estimated shock speeds

The shocks along the edges of the fingers are radiative (detailed discussion in section 9 p 286). The cooling time behind the shock is weeks. So energy from an ongoing fast wind is needed in order to maintain the radiation in the finger edges

The measured density along the length of the fingers is 5000 cm-3 with only small and local variations. This constant density contrasts with the density distribution of the surrounding neutral gas.

(BB: question for the Rochester crew: according to models, will the jets accelerate as they plow through decreasing ambient density? About knots, how will the general shapes of the fingers differ in an external medium that is (1) uniform, (2) declining as r^{-2? Can we use the shapes of the fingers to deduce the density falloff in the external medium?)}

============== More recent CO observations with somewhat higher spatial resolution and a spatio-kinematic model of the ambient molecular cloud

============== (movie 1)

============== Martin, two of the most notable features of the evolving structure of CRL618 are the motions and brightness changes of the tips of the fingers. This is seen on the 3-frame movie that's attached. open it with a browser. The movie frames are from 1998, 2002, and 2009 (not equally spaced)

One thing that we have yet to explore with the models is the changes in tip brightness as the tips cross the rings in the dust distribution. One might expect them to brighten as the bullets or jets encounter rings of higher density and to fade in between. In fact, after I stare at the movie, I think that I see the reverse…the tips fade when they hit the rings. Of course, the enhanced foreground extinction will affect the optical brightness.

Too bad that we don't have an IR move of the fingertips!

movie 2

============== Balick's first thoughts on the models 92/10/12)

FILES:

Older model info

Posted: 13 years ago (Updated: 12 years ago)
Author: martinhe
Categories: (none)

Comments

1. martinhe -- 13 years ago

Bruce asks:

The models predict an evolving morphology for the fingers that is sensitive to the grand structure of the ambient medium that they disrupt. Aside from the rings, can we use the observed finger morphology to constrain this external density distribution?

I say, yes. Our models with a flat density profile ambient medium yield more elongated objects (http://www.pas.rochester.edu/~blin/jan2012crl618/clump-nostrat.gif) than those with a r^-2 density profile (compare with images at the top of this page), independently of the ambient shells (or rings).

2. martinhe -- 13 years ago

The O_I and S_II pv diagrams from Sachez-Contreras and Sahai (http://iopscience.iop.org/0004-637X/578/1/269/pdf/55888.web.pdf) have contours. I'll make the next set of pv diagrams with contours too in order to facilitate the comparison.

This pv diagram of theirs (see their Fig 2, top right) seems to show some similar-ish structure in adjacent contours. e.g. take the southern feature here. All the contours corresponding to large velocities (left ones) seem to be pinched towards the symmetry axis. Could this correspond to the rib-cage-looking features in our synthetic pv diagram corresponding to the clump at 60^o propagating though a ringed ambient medium ?

http://www.pas.rochester.edu/~martinhe/2011/crl/sanchez1.png

3. martinhe -- 13 years ago

Bruce:

Let me remind you that the problem with many of the P-V plots from Sanchez et al is that the slit 'sees' both nebular light all along the fingers and scattered stellar light adjacent to and on both sides of the dark gap that covers the star itself (near the vertical line). Halpha is by far the most affected. That's easy to see since the stellar Halpha line is both bright and broad and it dominates the spectrum for at least 2" in both directions from the star.

Chances are that the [SII] line is not affected by stellar light — the circumstellar envelope is so dense that the [SII] lines are suppressed by collisions. When I look at the contour map the lower half appears to be vertical and the upper half is both vertical and tilted. I don't understand this asymmetry in the kinematic pattern.

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