Fix particle type
Fix particle type

mit-crpg/openmc,wbinventor/openmc,amandalund/openmc,amandalund/openmc,paulromano/openmc,wbinventor/openmc,walshjon/openmc,mit-crpg/openmc,smharper/openmc,paulromano/openmc,shikhar413/openmc,smharper/openmc,amandalund/openmc,mit-crpg/openmc,liangjg/openmc,shikhar413/openmc,paulromano/openmc,walshjon/openmc,walshjon/openmc,mit-crpg/openmc,shikhar413/openmc,shikhar413/openmc,smharper/openmc,liangjg/openmc,amandalund/openmc,smharper/openmc,liangjg/openmc,paulromano/openmc,wbinventor/openmc,wbinventor/openmc,walshjon/openmc,liangjg/openmc