Far-ultraviolet investigation into the galactic globular cluster M30 (NGC 7099): I. Photometry and radial distributions

We present a far-ultraviolet (FUV) study of the globular cluster M30 (NGC 7099). The images were obtained using Advanced Camera for Surveys (ACS/SBC, F150LP, FUV) and Wide Field Planetary 2 (WFPC2, F300W, UV) which both on board Hubble Space Telescope (HST). FUV-UV colour-magnitude diagram (CMD) shows main sequence (MS) turnoff at FUV $\approx$ 22 mag 3 mag. MS extends 4 below turnoff, prominent horizontal branch (HB) blue straggler (BS) can be seen. A total 1218 stars, 185 red giant 47 BS stars 41 HB are identified, along with 78 sources blueward consist white dwarfs (WDs) objects in gap between WDs that include potential cataclysmic variable (CV) candidates. radial distribution population is concentrated towards centre, indicating mass segregation has occurred. sub-populations double appear mixed ultraviolet CMD, no significant central concentration CV candidates seen this cluster.