Vitarka means logical thinking in several ways due to curiosity. A superficial attempt is made to grasp any object. Superficial refers to a gross thing, a gross phenomenon for its sphere of action.
Asamprajnata Samadhi is the other form of trance. This is a seedless Samadhi,trance. There is no object for its basis.
Bhava is an objective existence. The objective existence is that in which living beings are born. Bhava prathyaya means that which forms due to birth.
vega means speed. Here, vega, the speed refers to vairagya. The goal is near for those who are keen and practice with high intensity.
Others, that is yogis, attain asamprajnata samadhi by upaya prataya, that is by practicing shraddha (faith), virya, (energy), smriti (memory) and Samadhi with prajna a discern mind; in sequence.
Besides, there are sadhakas, the practitioners at different levels in their faith, eagerness and intensity.