J1832.4-1627, the first eclipsing stream-fed intermediate polar

We present a photometric study of the newly discovered eclipsing intermediate polar J183221.56-162724.25 (in short J1832) with an orbital period 8.87 h. The system features box-like deep eclipse full width at 50% depth 1970 ± 2 s and large-amplitude coherent pulsation Pobs = 65.18 min, which represents either synodic (beat) or spin white dwarf (WD). ratio is Pspin/Porb 0.1091 0.1225, respectively. eclipsed light originates almost entirely from two accretion spots columns on WD, characteristics indicative pole flipping. There no evidence for disk, we identify J1832 as first deeply stream-fed polar. Our grizy photometry in yielded i-band AB magnitude Roche-lobe-filling secondary star 18.98(3), extinction EB − V 0.54 0.17, spectral type ∼K6. Dynamic models, fitting photometry, limit distance to between 1270 2500 pc masses star, M2, 0.16 1.0 M⊙, well within Gaia EDR3 confidence limits. Employing luminosity selection inspired by binary population studies yields mean M2 0.32 M⊙ 2σ upper 0.60 d 1596 1980 pc. located its Hertzsprung-Russell diagram Teff, 4120 K log(L2/L⊙) 0.92, where can evolve into ultracompact highly magnetic primary. displays variable rate, lapses repeatedly short-lived low states negligible accretion, currently that decreases timescale τ ∼ 3 × 105 yr. X-ray observations, optical spectroscopy, spectropolarimetry have high potential properties individual object general.