Valmiki Ramayana Yuddha Kanda Sarga 59 Shloka 140

रामः Rama, विह्वलन्तम् swooning, तम् him, प्रसमीक्ष्य seeing, अथ then, दीप्तम् flaming, अर्थचन्द्रम् crescent shaped, समाददे took up, तेन by that, महात्मा great soul, सहसा hastily, अर्कवर्णम् red like sun, किरीटम् crown, चिच्छेद broke into pieces.

Seeing Ravana swooning, great soul Rama took up a crescent shaped arrow and hastily broke his crown into pieces which were shining bright red like the Sun.