From 8f46fc1c64af4bd0baa04d6d955b6e3546b4f03f Mon Sep 17 00:00:00 2001
From: Miikka Vaisala <mvaisala@asiaa.sinica.edu.tw>
Date: Thu, 18 Jul 2019 16:20:00 +0800
Subject: [PATCH] Documentation for the planned sink particle property.

---
 doc/manual/convert.sh       |  1 +
 doc/manual/sink_particle.md | 43 +++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)
 create mode 100755 doc/manual/convert.sh
 create mode 100644 doc/manual/sink_particle.md

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