ner_tags: O O B-Person I-Person O O O O O O O O O O O O O B-Telescope B-Instrument O B-Telescope O O O O O B-Person I-Person I-Person O O O O O O O O O
tokens: We thank Deepto Chakrabarty for useful conversations and for providing input on the effective collecting area of RXTE -PCA and NICER. We are also grateful to Jean in’t Zand and the referee for valuable comments on the manuscript.