16443
First proposed by J. J. Thomson in 1904 soon after the discovery of the electron , but before the discovery of the atomic nucleus , the model tried to explain two properties of atoms then known : that electrons are negatively-charged particles and that atoms have no net electric charge .
 J. J. Thomson
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 J. J. Thomson