_version_ 1866916019845464064
author Wu, S. -Y.
Gritsevich, M.
Lao, Q. -H.
Castro-Tirado, A. J.
Li, Z.
Hu, Y. -D.
Pérez-García, I.
Sánchez-Ramírez, R.
Castro-Segura, N.
Fernández-García, E. J.
Caballero-García, M. D.
Guziy, S.
Olivares, I.
Sakowska, J. D.
García-Segura, G.
Hiriart, D.
Lee, W. H.
Meintjes, P. J.
van Heerden, H. J.
Martín-Carrillo, A.
Hanlon, L.
Maury, A.
Hernández-García, L.
Carrasco-García, I. M.
Castillo-Carrión, S.
Castellón, A.
Pandey, S. B.
del Pulgar, C. J. Pérez
Reina, A. J.
Bai, J. -M.
Fan, Y. -F.
Wang, C. -J.
Xin, Y. -X.
Xiong, D. -R.
Zhao, X. -H.
Mao, J.
Lun, B. -L.
Ye, K.
Cui, C. -Z.
Valeev, A. F.
Zhang, B. -B.
Sun, T. -R.
author_facet Wu, S. -Y.
Gritsevich, M.
Lao, Q. -H.
Castro-Tirado, A. J.
Li, Z.
Hu, Y. -D.
Pérez-García, I.
Sánchez-Ramírez, R.
Castro-Segura, N.
Fernández-García, E. J.
Caballero-García, M. D.
Guziy, S.
Olivares, I.
Sakowska, J. D.
García-Segura, G.
Hiriart, D.
Lee, W. H.
Meintjes, P. J.
van Heerden, H. J.
Martín-Carrillo, A.
Hanlon, L.
Maury, A.
Hernández-García, L.
Carrasco-García, I. M.
Castillo-Carrión, S.
Castellón, A.
Pandey, S. B.
del Pulgar, C. J. Pérez
Reina, A. J.
Bai, J. -M.
Fan, Y. -F.
Wang, C. -J.
Xin, Y. -X.
Xiong, D. -R.
Zhao, X. -H.
Mao, J.
Lun, B. -L.
Ye, K.
Cui, C. -Z.
Valeev, A. F.
Zhang, B. -B.
Sun, T. -R.
contents RX J1553.0+4457 (TMTS J15530469+4457458) is a detached post-common-envelope binary containing a cool white dwarf and an active late-type companion. We present a multi-wavelength study combining BOOTES multi-band photometry, six sectors of public TESS full-frame imaging, Einstein Probe/FXT X-ray observations, CAFOS optical spectroscopy, and archival ultraviolet-to-mid-infrared photometry. The BOOTES data reveal two short optical flares separated by about 3 h, with amplitudes of roughly 1-1.5 mag and faster decay at shorter wavelengths. The combined TESS light curve shows a stable signal at P = 0.083782 d, consistent with the first harmonic of the known spectroscopic orbital period, and its folded morphology indicates ellipsoidal modulation from a tidally distorted late-type companion rather than an irradiation-dominated waveform. TESS flare energetics lie in the active M-dwarf regime. The Einstein Probe/FXT spectra show a factor of about 4 decline in the 0.3-10 keV flux, mainly associated with decreasing emission measures. The broadband SED is reproduced by a cool white dwarf plus a late-type M dwarf, with no clear hot-continuum or mid-infrared excess. RX J1553.0+4457 is therefore best interpreted as a detached pre-cataclysmic binary whose rapid optical variability is dominated by magnetic activity and whose orbital modulation is ellipsoidal, although a weak wind-fed or intermittent accretion contribution remains possible.
format Preprint
id arxiv_https___arxiv_org_abs_2605_02796
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Ellipsoidal modulation and multi-wavelength activity in the pre-cataclysmic binary RX J1553.0+4457
Wu, S. -Y.
Gritsevich, M.
Lao, Q. -H.
Castro-Tirado, A. J.
Li, Z.
Hu, Y. -D.
Pérez-García, I.
Sánchez-Ramírez, R.
Castro-Segura, N.
Fernández-García, E. J.
Caballero-García, M. D.
Guziy, S.
Olivares, I.
Sakowska, J. D.
García-Segura, G.
Hiriart, D.
Lee, W. H.
Meintjes, P. J.
van Heerden, H. J.
Martín-Carrillo, A.
Hanlon, L.
Maury, A.
Hernández-García, L.
Carrasco-García, I. M.
Castillo-Carrión, S.
Castellón, A.
Pandey, S. B.
del Pulgar, C. J. Pérez
Reina, A. J.
Bai, J. -M.
Fan, Y. -F.
Wang, C. -J.
Xin, Y. -X.
Xiong, D. -R.
Zhao, X. -H.
Mao, J.
Lun, B. -L.
Ye, K.
Cui, C. -Z.
Valeev, A. F.
Zhang, B. -B.
Sun, T. -R.
Solar and Stellar Astrophysics
High Energy Astrophysical Phenomena
RX J1553.0+4457 (TMTS J15530469+4457458) is a detached post-common-envelope binary containing a cool white dwarf and an active late-type companion. We present a multi-wavelength study combining BOOTES multi-band photometry, six sectors of public TESS full-frame imaging, Einstein Probe/FXT X-ray observations, CAFOS optical spectroscopy, and archival ultraviolet-to-mid-infrared photometry. The BOOTES data reveal two short optical flares separated by about 3 h, with amplitudes of roughly 1-1.5 mag and faster decay at shorter wavelengths. The combined TESS light curve shows a stable signal at P = 0.083782 d, consistent with the first harmonic of the known spectroscopic orbital period, and its folded morphology indicates ellipsoidal modulation from a tidally distorted late-type companion rather than an irradiation-dominated waveform. TESS flare energetics lie in the active M-dwarf regime. The Einstein Probe/FXT spectra show a factor of about 4 decline in the 0.3-10 keV flux, mainly associated with decreasing emission measures. The broadband SED is reproduced by a cool white dwarf plus a late-type M dwarf, with no clear hot-continuum or mid-infrared excess. RX J1553.0+4457 is therefore best interpreted as a detached pre-cataclysmic binary whose rapid optical variability is dominated by magnetic activity and whose orbital modulation is ellipsoidal, although a weak wind-fed or intermittent accretion contribution remains possible.
title Ellipsoidal modulation and multi-wavelength activity in the pre-cataclysmic binary RX J1553.0+4457
topic Solar and Stellar Astrophysics
High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2605.02796