Dear yt:

I have one simple question, but it bothers me these days.

I used the yt to analysis the "hdf5" files, which generated by Gadget-2. These files have basic fields, like: ("PartType0", "*"), ("PartType1", "*") and ("all", "*"). Then I want to plot the density map and temperature map, it seems need some derived fields, like: ("gas", "density") and ("gas", "temperature").

I'm curious about how the ("gas","temperature") was derived, so I browsed a lots of documents on the Web, but found nothing. Please see
http://yt-project.org/doc/reference/field_list.html?highlight=field%20list
About the field of ('gas','temperature'),  there is "No source available" in "Field Source"!

In my data, the field ("PartType0","InternalEnergy") is provided by me, and I think the temperature should calculated by Internal Energy "E" with the function: k*T = (Gamma -1)*µ*mp*E, where k = 1.38E-16 erg/K is Boltzmann constant, Gamma = 5/3 for adiabat particles, μ = 0.6 is the corresponding mean molecular weight, and mp = 1.67E-24 g is proton mass. But this result is about half of the value of ("gas","temperature").
So what you may know is why, which one is right? I need your help!

Thank you a lot, and happy new year!

Regard,
Dan


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Dan Hu
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Department of Physics, Shanghai Jiao Tong University
800 Dongchuan Road, Minhang, Shanghai 200240, PRC
E-mail : hudan_bazhaoyu@163.com
             hudan_bazhaoyu@sjtu.edu.cn
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