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floyd0117
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If I have a cluster with a mass measured in M_500c, then how do I go about converting that mass to M_200c given some concentration and an NFW profile?
Chalnoth said:What do you mean converting the mass? What are you converting? Why?
Ahh, okay. I'm honestly not sure. I did find this resource, which describes these measures a bit:floyd0117 said:I have a dataset of cluster masses, expressed in units of M_500c, which I need to relate to a velocity dispersion. But the relation between cluster mass and velocity dispersion is in terms of M_200c, so I need to convert the masses in the dataset before I can find the equivalent dispersions.
Chalnoth said:Ahh, okay. I'm honestly not sure. I did find this resource, which describes these measures a bit:
https://www.princeton.edu/astro/undergraduate/astro-jps-senior-theses-a/bilhudathesis-2.pdf [Broken]
It looks like [itex]M_{500}[/itex] is the mass within [itex]R_{500}[/itex], while [itex]M_{200}[/itex] is the mass within [itex]R_{200}[/itex], where [itex]R_{500} \approx 0.7 R_{200}[/itex]. If you've got a good understanding of the NFW profile, you might be able to use that to do the conversion.
That said, my guess is it'd be even better to convert the relation between mass and dispersion to be in terms of [itex]M_{500}[/itex] instead of [itex]M_{200}[/itex], as that's most likely a far simpler operation.
Makes sense. Sorry I can't be of more help.floyd0117 said:Perhaps, but I'm trying to follow the methodology presented in a specific paper and replicate their results. Thanks anyway
To convert from grams to kilograms, divide the number of grams by 1000. To convert from kilograms to grams, multiply the number of kilograms by 1000.
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The formula for converting metric tons to kilograms is 1 t = 1000 kg. To convert from metric tons to kilograms, multiply the number of metric tons by 1000. To convert from kilograms to metric tons, divide the number of kilograms by 1000.
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