Meeting update
~Papers~
MHD shock paper
Check out outline on sharelatex
Paper ideas (for undergrad project)
Connie says there are no REU students, but that there may be undergrads available if Adam wants to hire them off of his grants?? I did a search and couldn't find any abstracts with the words Bonnor Ebert, radiation or radiative transfer. I think an easy project for a student would be running the collapse of a BE sphere with rad feedback. This could be a very high resolution run (AU scale, and could include MHD), where a disk forms. The questions might be:
- How does M-dot (and hence, accretion luminosity/rad feedback) change with rad feedback (relevant to the "luminosity problem" we were learning about last week)
- How does M-dot and rad feedback change when the BE sphere is embedded in 'realistic, continuous density medium'.
Paper ideas inspired by new Krumholz et al
Disentangling the effect of the outflows on support surrounding young protostars
Studying the role of turbulence and/or density fluctuations (last paragraph of conclusion says that is lacking)
Paper makes conclusions based on drawing spheres around sinks and calculating various critical masses — but can we test these ideas? under what limits do these ideas hold or not? Basically, trying to get a physical handle on the problem. Maybe this can also help with understanding why the accretion flow is not Bondi.
Update 03/28/16 - Eddie
- 3-D pulsed jets are still running, only hydro run is finished. Beta = 1 run will be done in about a week on bluehive, beta = 5 is 75% done and beta = 0.4 is only 50% done on davinci. The queues on davinci take way too long, so I'm going to move the beta = 0.4 run to bluehive as well. It'll take a while since I can only get 120 cores, but at least it'll be making progress.
- Ready to finish response to referee report on clumpy paper. Need to have meeting with Pat.
- Finished first draft of cooling paper, ready to revise and add figures. Working on some cooling curve plots now.
Meeting Update
Mean Vorticity
Query results:
For S0:
"Average value" | The average value of 3D/AbsVorticity is 22.2432 |
"Sample Stats" | Mean=97.3728, Std Dev= 115.999, Variance=13,455.7, Skewness = 1.78141, Kurtosis = 3.66127 |
"Variable Sum" | The total 3D/AbsVorticity is 7.55786e+08 |
"Weighted Variable Sum" | The total 3D/AbsVorticity is 156,936 |
" NumZones" | The original number of zones is 11,114,080. |
"Weighted Variable Sum" | The total rho is 35,091.4 |
"Volume" | The total Volume is 7,055.47 |
Types of mean from query output:
Variable sum vorticity/NumZones = 68
Variable sum vorticity/Mass hockey puck = 21,537.9
Variable sum vorticity/ volume hockey puck = 107,120
Weighted sum vorticity/Numzones = .014
Weighted sum vorticity/Mass = 4.5
Weighted sum vorticity/Volume = 22.24
For S60:
"Average value" | The average value of 3D/AbsVorticity is 37.8458 |
"Sample Stats" | The average value of 3D/AbsVorticity is 37.8458, Mean=7.8336, Std Dev = 45.8268, Variance = 2,100.09, Skewness = 1.35431, Kurtosis = 1.48626 |
"Variable Sum" | The total 3D/AbsVorticity is 8.31277e+07 |
"Weighted Variable Sum" | The total 3D/AbsVorticity is 662,507 |
" NumZones" | The actual number of zones is 4,836,010 |
"Weighted Variable Sum" | The total rho is 35,027.1 |
"Volume" | The total Volume is 17,505.4 |
Types of mean from query output:
Variable sum vorticity/NumZones = 17.19
Variable sum vorticity/Mass hockey puck = 2,373
Variable sum vorticity/ volume hockey puck = 4,748
Weighted sum vorticity/Numzones = .137
Weighted sum vorticity/Mass = 18.9
Weighted sum vorticity/Volume = 37.8458
Meeting Update
Histos
"Density Weighted":
This plot is the one I sent around yesterday.
The issue may be that the y scaling is way off given the mass flux (and total masses) of the hockey pucks vary so much. To clarify, the masses of the various hockey pucks are (S0→S60):
S0 | 35091 |
S15 | 34735 |
S30 | 31640 |
S60 | 16894 |
So, I then defined a new variable that divides rho by the total mass of the puck for each of the runs. This is the "mass normalized rho", and then weighted the histos by these variables.
"Mass normalized rho weighted" (linear bin scale):
"Mass normalized rho weighted" (log bin scale):
Next, instead of weighting by a variable, did the histo by 'frequency':
So, in all of these cases, regardless of y-axis scaling, the max vorticity is highest in the lower shear cases… perplexing :-/
Min/Max Vorticity
S0 | 5e-5/1068 |
S15 | 1e-4/1005 |
S30 | 2e-4/949 |
S60 | .017/310 |
Histo of vx
Instead of vorticity, how about spread in v? Or RMS v?
Here is vx histo for the diff runs:
Shock solutions
https://astrobear.pas.rochester.edu/trac/wiki/u/erica/scratch3
Calculating the M2FR
Link: http://mnras.oxfordjournals.org/content/414/3/2511.full.pdf
Estimating Timescales for Radiation Diffusion
So this is an execerise in thinking dimensionally and in order of magnitudes.
Consider the equation for radiation energy conservation ignoring a bunch of terms that should be of lower order
The second term on the right hand side tells us about the diffusion of radiation and the right hand term tells us about coupling with matter.
Lets consider the diffusion term to get an estimate of the timescale,
We do this terms of dimensions (L = length, T= time etc). Radiation energy density E is, for example
So the diffusion term reads
which has units of energy of time as would be expected. To get a timescale for radiative diffusion
we can write things in terms of the scales of the problem and
or
Note
drops out hereNow we just have to find values of the Rosseland opacity relevant to something like a dusty in falling protostellar envelope. I am seeing the Rosseland opacity being given in units of cm^{2/g which means we will need to multiply by a density scale in the above expression i.e. }
where
is the value we get from tables and is our density scale.Here is a paper I found that gives some useful opacity information
http://www.aanda.org/articles/aa/full/2003/41/aa3802/aa3802.right.html
Check out this table from the paper
Meeting update
- considering trajectories in lab frame
- Wire turbulence MHD run is at 157 and running well…
- Working on paper…
More reasonable one dimensional AGB wind
I intend to put this new wind model into our code. This movie shows only a radiative driven pulsating AGB wind. It has cooling.
I am going to apply it to the binary paper.
Update 03/11/2016 - Eddie
- Worked on cooling paper: abstract, intro, methods sections finished. Might've finished the whole thing had I not focused so much on recent referee report. I can release these sections for edits, and continue working on the rest.
- Worked on referee report for clumpy paper. I think most of it is resolved, and I don't think we have to change the paper too much. However, we still need to have a co-author discussion about gammas, cooling, and Mach stems. Below is a test simulation I ran to show that simulating a more "realistic" clump does not change our conclusions.
- 3-D jet simulations are still going. Here's a status update:
Beta | Frame (out of 120) | Est. Wall Time Remaining |
---|---|---|
Inf | 103 | 10.7 hours |
5 | 76 | 2.1 days |
1 | 88 | 17.4 days |
0.4 | 55 | 4.2 days |
The beta=1 run will take significantly longer because it's on bluehive, but the other runs wait in the queue for so long in between restarts on davinci that all of these runs may finish around the same time in 3 weeks or so. Honestly don't see this project finishing in time to be part of my thesis, especially since we wanted to do additional runs with random pulses, less frequent pulses, no pulses, etc.
Meeting Update
Papers
Referee Report Points:
The ref says, "Here, I list some points which should be added/clarified:"
1. Discussion on the mass-to-flux ratio / inflow boundaries: This should be complemented with a plot showing the total gas mass (and/or the column density) in the simulation box as a function of time. This plot should then also show the total mass-to-flux ratio as a function of time. | ||
2. Protocluster formation and evolution: Again, a plot showing the mass evolution of the sink particles would be very helpful. Also the mass accretions as function of time would be illustrative. | Give a plot of mass 1 Myr after formation. | X |
3. Furthermore, it is not clear why younger clusters (later formation time) have a higher final mass. Please include a discussion (helpful with the above mentioned plots). | Have this plot for the S0 case, will send him this one. | X |
4. The cartoons (Fig. 5) on the magnetic ring model are confusing: It looks like that a ring like structure (resp. spherical bubble) is expanding in the plane of the flows, i.e. in the xz-plane. This is certainly not true (see Fig. 3). For the cartoons it would be better to use two different views, according to the numerical setup, i.e. a view in the yz- and a xz-plane. | ||
5. About the discussion on the impact of shear/power spectra: Here, it would be also useful to show the generated vorticity. E.g., an increasing vorticity could also explain the reduced star formation. |
Other points:
Include citations to work by Federrath and Dobbs | |
Sink plot after 2 Myr | |
Shear plot |
Data we are missing:
Run | Frames |
0 | 273/273 |
15 | 200/273 |
30 | 200/273 |
60 | 329/329 |
3D volume rendering movies for "Hot Planet Winds Near a Star"
High Res Movies
Versions | mov | avi | mp4 | mpeg |
fixed | fixed mov | fixed avi | fixed mp4 | fixed mpeg |
rotate | rot mov | rot avi | rot mp4 | rot mpeg |
Flow Texture
Old Versions
Versions | gif | mov | avi | mp4 | mpeg |
1 | fixed | fixed mov | fixed avi | fixed mp4 | fixed mpeg |
2 | rotate | rot mov | rot avi | rot mp4 | rot mpeg |
3 | rotate | rot mov | rot avi | rot mp4 | rot mpeg |
Update 3/7
Read Murray-Clay paper: Authors seek to numerically determine validity of hypothesis that hot Jupiters could be evaporated down to their rocky cores over the planetary lifetime. They use a one-dimensional model that includes heating/cooling terms, tidal gravity, and the effects of ionization on the mass-loss rate, and ignore the Coriolis force. Numerically, they use a relaxation solver, and find solutions iteratively by removing simplifying conditions one at a time.
They find that, for main-sequence stars, about 20% of H is still neutral at the sonic point, and place an upper bound of ~3.3*10^{10} g/s on the mass loss rate. For hotter (T Tauri) stars, they find an upper bound of ~6.4*10^{12} g/s. The assumption of a hydrodynamic wind is shown to be self-consistent, and they estimate that these are overestimates by ~4x. By reducing the wind speed to subsonic values and including a stellar wind, the day-side wind may be reduced or completely suppressed - they hypothesize that this may lead to night-side outflows.
They compare observations to estimates from their model, and note a few possible reasons for the disagreement in Lyman-alpha lines. A promising candidate is cited as acceleration of neutral hydrogen due to charge exchange. They note that modelled spectrally-unresolved measurements appear to be in agreement with observation.
List of Key Simulation Papers for Planet Winds
Matsakos et al 2015 http://adsabs.harvard.edu/abs/2015A%26A...578A...6M
Tripathi 2016 http://adsabs.harvard.edu/abs/2015ApJ...808..173T
Frank et al 2015 http://adsabs.harvard.edu/abs/2015IAUS..314..237F
Stugaret 2015 http://adsabs.harvard.edu/abs/2015ApJ...815..111S
Christie http://adsabs.harvard.edu/abs/2016arXiv160105302C
Schnieter 2016 http://adsabs.harvard.edu/abs/2016MNRAS.457.1666S
Scnieter 2007 http://adsabs.harvard.edu/abs/2007ApJ...671L..57S
Bourrier 2013 http://adsabs.harvard.edu/abs/2013A%26A...557A.124B
Cohen 2009 http://adsabs.harvard.edu/abs/2009ApJ...704L..85C
Cohen 2010 http://adsabs.harvard.edu/abs/2011ApJ...733...67C