Bernardini, F.de Martino, D.Mukai, K.Israel, G.Falanga, M.Ramsay, G.Masetti, N.2023-06-202023-06-202015-11Monthly Notices of the Royal Astronomical Society. Volume 453, Issue 3, Pages 3100 - 3106. 1 November 20150035-8711https://repositorio.unab.cl/xmlui/handle/ria/50853Indexación: Scopus.IGR J04571+4527 and Swift J0525.6+2416 are two hard X-ray sources detected in the Swift/BAT and INTEGRAL/IBIS surveys. They were proposed to be magnetic cataclysmic variables of the intermediate polar (IP) type, based on optical spectroscopy. IGR J04571+4527 also showed a 1218 s optical periodicity, suggestive of the rotational period of a white dwarf, further pointing towards an IP classification. We here present detailed X-ray (0.3–10 keV) timing and spectral analysis performed with XMM–Newton, complemented with hard X-ray coverage (15–70 keV) from Swift/BAT. These are the first high-S/N observations in the soft X-ray domain for both sources, allowing us to identify the white dwarf X-ray spin period of Swift J0525.6+2416 (226.28 s), and IGR J04571+4527 (1222.6 s). A model consisting of multitemperature optically thin emission with complex absorption adequately fits the broad-band spectrum of both sources. We estimate a white dwarf mass of about 1.1 and 1.0 M⊙ for IGR J04571+4527 and Swift J0525.6+2416, respectively. The above characteristics allow us to unambiguously classify both sources as IPs, confirming the high incidence of this subclass among hard X-ray emitting cataclysmic variables.enNovaeCataclysmic VariablesWhite DwarfsX-rays: individual: IGR J04571+4527 (1RXS J045707.4+452751, as Swift J0457.1+4528)As WISE J052522.84+24133333.6)ArtículoAtribution 4.0 International (CC BY 4.0)10.1093/mnras/stv1673