context: Paila Baishakh or Pahala Baishakh (the first month of Baishakh, the first month of the Bengali calendar) is the first day of Bangabha, that is, Bengali New Year. The day is the traditional rainy day of the Bengali nation. The day is celebrated as a New Year in West Bengal in Bangladesh and India. Bengalis living in Tripura also participate in the festival. As such, it is regarded as a universal folk festival of the Bengalis. [1]
question: What is the first day of the Bengali New Year called?