heat of passion vs indignation

heat of passion

noun
  • An outburst of anger that leads one to commit a criminal act, and is itself influenced by preceding events that might cause a reasonable person to lose self control. 

indignation

noun
  • An anger aroused by something perceived as an indignity, notably an offense or injustice. 

  • A self-righteous anger or disgust. 

How often have the words heat of passion and indignation occurred in a corpus of books? (source: Google Ngram Viewer )