So happy to have pulse, at two low temperatures (8)
I believe the answer is:
beatific
'so happy' is the definition.
'beatific' can be an answer for 'happy' (thesaurus). I am not certain of the 'so' bit.
'pulse at two low temperatures' is the wordplay.
'pulse' becomes 'be at' (synonyms).
'at' means one lot of letters go next to another.
'two low temperatures' becomes 'ific' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'beat'+'ific'='BEATIFIC'
'to have' is the link.
Can you help me to learn more?
(Other definitions for beatific that I've seen before include "Joyful" , "Befit CIA to be showing great happiness" , "Feeling or expressing blissful happiness" , "Showing great happiness, perhaps a smile" , "Angelic, saintly" .)