CPD–82 291: Multi-sector TESS Photometry and SED Analysis of an Active Eclipsing Binary
Publications of the Astronomical Society of the Pacific, cilt.138, sa.9, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 138 Sayı: 9
- Basım Tarihi: 2026
- Doi Numarası: 10.1088/1538-3873/ae9c97
- Dergi Adı: Publications of the Astronomical Society of the Pacific
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC, Academic Search Ultimate (EBSCO)
- Anahtar Kelimeler: Eclipsing binary stars (444), Pre-main sequence stars (1290), Protoplanetary disks (1300), Spectral energy distribution (2129), Young stellar objects (1834)
- Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
- Akdeniz Üniversitesi Adresli: Evet
Özet
We present a multi-sector TESS photometric and spectral energy distribution analysis of the eclipsing binary CPD–82 291 (RX J0853.1–8244). Eight TESS sectors reveal well-defined eclipses and substantial, changing out-of-eclipse modulation. The asymmetries are reproduced by different surface-brightness configurations at different epochs, consistent with strong and evolving stellar activity, although the fitted circular regions are not unique maps of individual starspots. A detached-binary light-curve model yields an orbital inclination of (Formula presented) i≃82.°1 and a photometric mass ratio of qphot ≃ 0.464. Without a spectroscopic radial-velocity orbit, the mass ratio and absolute parameters are model dependent rather than dynamical measurements. Combining the light-curve geometry with the SED radius scale and Gaia distance gives R1 ≃ 1.25 R⊙ and R2 ≃ 3.70 R⊙; the corresponding model-inferred masses remain substantially less secure than the dimensionless light-curve parameters. The stellar photospheres reproduce the observed SED from the optical region through WISE W4, with no statistically significant mid-infrared excess. The only positive long-wavelength deviation is a low-significance 60 μm measurement, while the 90 μm result is an upper limit. A cool circumbinary-dust model can reproduce this tentative signal, but such a component is not required by the photometry, and its inferred mass and radial extent are non-unique and strongly model dependent. Evolutionary tracks place the primary close to the zero-age main sequence and the secondary well above the main-sequence locus. However, the absence of radial velocities and spectroscopic youth indicators, together with Gaia astrometry inconsistent with Chamaeleon I membership, prevents a secure pre-main-sequence classification. CPD–82 291 is therefore best regarded as an active eclipsing binary with uncertain evolutionary status and only a marginal far-infrared indication that could be reproduced by cool circumstellar material.