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I am trying to look up StoppingPowerData for a number of elements and while this snippet works for several I have tried (Aluminum, Lead, Iron for example), I get a result of (not available), but no error, when I try with others, such as Carbon. I've tried specifying an isotope of Carbon as well as different incoming particles and different energies.

StoppingPowerData[
Entity["Element", "Carbon"],
{"Particle" -> "Proton","Energy" -> Quantity[500,"Kiloelectronvolts"]},
"LinearStoppingPower"]

Does anyone know what the issue might be?

Thanks.

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  • 1
    $\begingroup$ Have a look at the "possible issues" in the help docs: "Not all properties support all particles". Missing[NotAvailable] just means there's no data entered for those lookup parameters. $\endgroup$ – dionys Nov 7 '16 at 12:42
  • $\begingroup$ Is it possible to find out what parameters it does support? StoppingPowerData[] shows Carbon as being an available parameter, but I've tried a range of energies and different properties and everything seems to give not available? $\endgroup$ – Cod Fish Nov 7 '16 at 13:12
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As far as I know, StoppingPowerData is just a construct to interface with a compilation of NIST data, along the same lines as ChemicalData and ThermodynamicData. They cite three primary sources in the help docs:

Mma provides an error message to let you know when you specify energies that are out of range:

StoppingPowerData::orng: Energy should be between 10000. eV and 1.1*10^10 eV.

Also, data is not available for all property/particle/element combinations. Missing[NotAvailable] is returned in cases where StoppingPowerData can't find anything for the specified lookup parameters. You can use TableForm to make a rough visual check:

Module[{props, test},
 props = StoppingPowerData["Properties"]; 
 test = StoppingPowerData[
     Entity["Element", "Lead"], {"Particle" -> "Proton", 
      "Energy" -> Quantity[500, "Kiloelectronvolts"]}, #] & /@ props;
 TableForm[Transpose[{props, test}]]]

enter image description here

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