{"work":{"id":"bc7daa59-acdf-4564-be7c-dfdaf671f6f0","openalex_id":null,"doi":"10.1146/annurev.astro.44.051905.092532","arxiv_id":"1905.09253","raw_key":null,"title":"Broadband reflection spectroscopy of MAXI J1535-571 using AstroSat: Estimation of black hole mass and spin","authors":null,"authors_text":null,"year":2019,"venue":"astro-ph.HE","abstract":"We report the results from \\textit{AstroSat} observations of the transient Galactic black hole X-ray binary MAXI J1535-571 during its hard-intermediate state of the 2017 outburst. We systematically study the individual and joint spectra from two simultaneously observing \\textit{AstroSat} X-ray instruments, and probe and measure a number of parameter values of accretion disc, corona and reflection from the disc in the system using models with generally increasing complexities. Using our broadband ($1.3-70$ keV) X-ray spectrum, we clearly show that a soft X-ray instrument, which works below $\\sim 10-12$ keV, alone cannot correctly characterize the Comptonizing component from the corona, thus highlighting the importance of broadband spectral analysis. By fitting the reflection spectrum with the latest version of the \\textsc{relxill} family of relativistic reflection models, we constrain the black hole's dimensionless spin parameter to be $0.67^{+0.16}_{-0.04}$. We also jointly use the reflection spectral component (\\textsc{relxill}) and a general relativistic thin disc component (\\texttt{Kerrbb}), and estimate the black hole's mass and distance to be $10.39_{-0.62}^{+0.61} M_{\\odot}$ and $5.4_{-1.1}^{+1.8}$ kpc respectively.","external_url":"https://arxiv.org/abs/1905.09253","cited_by_count":null,"metadata_source":"pith","metadata_fetched_at":"2026-07-10T00:15:00.872479+00:00","pith_arxiv_id":"1905.09253","created_at":"2026-05-19T21:57:48.290017+00:00","updated_at":"2026-07-11T11:50:26.030339+00:00","title_quality_ok":true,"display_title":"Broadband reflection spectroscopy of MAXI J1535-571 using AstroSat: Estimation of black hole mass and spin","render_title":"Broadband reflection spectroscopy of MAXI J1535-571 using AstroSat: Estimation of black hole mass and spin"},"hub":{"state":{"work_id":"bc7daa59-acdf-4564-be7c-dfdaf671f6f0","tier":"hub","tier_reason":"10+ Pith inbound or 1,000+ external citations","pith_inbound_count":19,"external_cited_by_count":null,"distinct_field_count":3,"first_pith_cited_at":"2019-06-25T15:15:29+00:00","last_pith_cited_at":"2026-07-08T15:57:44+00:00","author_build_status":"not_needed","summary_status":"needed","contexts_status":"needed","graph_status":"needed","ask_index_status":"not_needed","reader_status":"not_needed","recognition_status":"not_needed","updated_at":"2026-08-03T05:56:40.731001+00:00","tier_text":"hub"},"tier":"hub","role_counts":[],"polarity_counts":[],"runs":{},"summary":{},"graph":{},"authors":[]}}