THE LATE B-TYPE STARS - REFINED MK CLASSIFICATION, CONFRONTATION WITH STROMGREN PHOTOMETRY, AND THE EFFECTS OF ROTATION

In the fourth and final of a series of papers on the late B to the early F type stars, we refine the MK spectral classification system for the.late B type stars and consider the effect of rotation on both spectral classification and Stromgren photometry of these stars. We extend the work of Morgan by establishing self-consistent sequences of narrow and broadlined standards. We reclassify a number of Bp stars, compare these classifications with Stromgren photometry and consider the question of whether all Bp stars are main-sequence objects.