44 lines
1011 B
Markdown
44 lines
1011 B
Markdown
# Sink particle
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The document aims to describe how the sink particle is calculated.
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For referfence see Lee et al. (2014) Apj, 783, 50.
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## Stage 1: Initialization
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Create datatype `sink` with coordinate and location for the particle.
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```c
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sink.x
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sink.y
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sink.z
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sink.mass
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```
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Either we start with an initial particle, or we can assume it to form later
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(e.g. based on Truelove criterion.)
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## Stage 2: Communication (host to device)
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Values of `sink` need to be communicated from Host to Device.
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## Stage 3: Gravitation
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Based on `sink` gravitational force effect is added to the momentun equation (via DSL).
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## Stage 4: Accretion
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Jeans length
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\begin{equation}
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\lambda_\mathrm{J} = \Big( \frac{\pi c_s^2}{G \rho} \Big)^{1/2}
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\end{equation}
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Truelove-Jeans density.
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\begin{equation}
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\rho_\mathrm{TJ} = \frac{\pi J^2 c_s^2}{G \Delta x^2}
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\end{equation}
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where $J = \Delta x / \lambda_\mathrm{J}$
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## Stage 5: Data gathering (device to host)
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We need to combine accretion calculated in multiple GPUs.
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