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تسجيل مستخدم جديدDiscovery of 13 New Orbital Periods for Classical Novae
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Bradley E. Schaefer
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I report new orbital periods (P) for 13 classical novae, based on light curves from TESS, AAVSO, and other public archives. These new nova periods now constitute nearly one-seventh of all known nova periods. Five of my systems have P>1 day, which doubles the number of such systems that must have evolved companion stars. (This is simply because ground-based time series have neither the coverage nor the stability required to discover these small-amplitude long periods.) V1016 Sgr has a rare P below the period gap, and suddenly becomes useful for current debates on evolution of novae. Five of the novae (FM Cir, V399 Del, V407 Lup, YZ Ret, and V549 Vel) have the orbital modulations in the tail of the eruption after the transition phase. Soon after the transition, YZ Ret shows a unique set of aperiodic diminishing oscillations, plus YZ Ret shows two highly-significant transient periods, 1.1% and 4.5% longer than the orbital period, much like for the superhump phenomenon. I also report an optical 591.27465 second periodicity for V407 Lup, which is coherent and must be tied to the white dwarf spin period. The new orbital periods in days are 0.1883907 +- 0.0000048 for V1405 Cas, 3.4898 +- 0.0072 for FM Cir, 0.162941 +- 0.000060 for V339 Del, 3.513 +- 0.020 for V407 Lup, 1.32379 +- 0.00048 for V2109 Oph, 3.21997 +- 0.00039 for V392 Per, 0.1628714 +- 0.0000110 for V598 Pup, 0.1324539 +- 0.0000098 for YZ Ret, 0.07579635 +- 0.00000017 for V1016 Sgr, 7.101 +- 0.016 for V5583 Sgr, 0.61075 +- 0.00071 for V1534 Sco, 0.40319 +- 0.00005 for V549 Vel, and 0.146501 +- 0.000058 for NQ Vul.
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