2020/11/07 by Gunjan Tomar, Pragati Pradhan, Biswajit Paul
Earth and Planetary Sciences · Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Binary pulsar #Cyclotron #High-pressure geophysics and materials #Line (geometry) #Luminosity #Millisecond pulsar #Nuclear physics #Physics #Plasma #Pulsar #Pulsars and Gravitational Waves Research #Spectral line #astro-ph.HE
paper · pdf · doi:10.1093/mnras/staa3477
8 pages, 5 figures, accepted for publication in MNRAS
openalex publication_date 2020/11/07 · arxiv created 2020/11/11 · arxiv updated 2020/11/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT We report results from the analysis of data from two observations of the accreting binary X-ray pulsar Cen X-3 carried out with the broad-band X-ray observatories Suzaku and NuSTAR. The pulse profile is dominated by a broad single peak and show some energy dependence with two additional weak pulse peaks at energies below 15 and 25 keV, respectively. The broad-band X-ray spectrum for 0.8–60.0 keV for Suzaku and 3.0–60.0 keV for NuSTAR is fitted well with high-energy cut-off power-law model along with soft-excess, multiple iron emission lines and a cyclotron absorption. The cyclotron line energy is found to be 30.29+0.68-0.61 and 29.22+0.28-0.27 keV, respectively, in the Suzaku and NuSTAR spectra. We make a comparison of these two measurements with four previous measurements of Cyclotron Resonant Scattering Feature (CRSF) in Cen X-3 obtained with Ginga, BeppoSAX, and RXTE. We find no evidence for a dependence of the CRSF on luminosity. Except for one CRSF measurement with BeppoSAX , the remaining measurements are consistent with a CRSF energy in the range of 29.5–30.0 keV over a luminosity range of 1.1–5.4 × 1037 erg s−1 different from several other sources that show considerable CRSF variation in the same luminosity range.