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   https://doi.org/10.3847/1538-4357/ac32be  

   Cufari, M.; Coughlin, Eric R.; Nixon, C. J. (January 2022, The Astrophysical Journal)

   Abstract Upon entering the tidal sphere of a supermassive black hole, a star is ripped apart by tides and transformed into a stream of debris. The ultimate fate of that debris, and the properties of the bright flare that is produced and observed, depends on a number of parameters, including the energy of the center of mass of the original star. Here we present the results of a set of smoothed particle hydrodynamics simulations in which a 1 M ⊙ , γ = 5/3 polytrope is disrupted by a 10 6 M ⊙ supermassive black hole. Each simulation has a pericenter distance of r p = r t (i.e., β ≡ r t / r p = 1 with r t the tidal radius), and we vary the eccentricity e of the stellar orbit from e = 0.8 up to e = 1.20 and study the nature of the fallback of debris onto the black hole and the long-term fate of the unbound material. For simulations with eccentricities e ≲ 0.98, the fallback curve has a distinct, three-peak structure that is induced by self-gravity. For simulations with eccentricities e ≳ 1.06, the core of the disrupted star reforms following its initial disruption. Our results have implications for, e.g., tidal disruption events produced by supermassive black hole binaries. 

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2. Magnetorotational Instability in Eccentric Disks

   https://doi.org/10.3847/1538-4357/aab15c  

   Chan, Chi-Ho; Krolik, Julian H.; Piran, Tsvi (March 2018, The Astrophysical Journal)
3. Analytic waveforms for eccentric gravitational wave bursts

   https://doi.org/10.1088/1361-6382/ab745f  

   Loutrel, Nicholas (April 2020, Classical and Quantum Gravity)
4. The eccentric behavior of inspiralling compact binaries

   https://doi.org/10.1088/1361-6382/aaf2a9  

   Loutrel, Nicholas; Liebersbach, Samuel; Yunes, Nicolás; Cornish, Neil (January 2019, Classical and Quantum Gravity)
5. An Eccentric Brown Dwarf Eclipsing an M dwarf

   https://doi.org/10.3847/1538-3881/ac415f  

   Cañas, Caleb I.; Mahadevan, Suvrath; Bender, Chad F.; Salazar Rivera, Noah Isaac; Monson, Andrew; Beard, Corey; Lubin, Jack; Robertson, Paul; Gupta, Arvind F.; Cochran, William D.; et al (January 2022, The Astronomical Journal)

   Abstract We report the discovery of an M = 67 ± 2 M J brown dwarf transiting the early M dwarf TOI-2119 on an eccentric orbit ( e = 0.3362 ± 0.0005) at an orbital period of 7.200861 ± 0.000005 days. We confirm the brown dwarf nature of the transiting companion using a combination of ground-based and space-based photometry and high-precision velocimetry from the Habitable-zone Planet Finder. Detection of the secondary eclipse with TESS photometry enables a precise determination of the eccentricity and reveals the brown dwarf has a brightness temperature of 2100 ± 80 K, a value which is consistent with an early L dwarf. TOI-2119 is one of the most eccentric known brown dwarfs with P < 10 days, possibly due to the long circularization timescales for an object orbiting an M dwarf. We assess the prospects for determining the obliquity of the host star to probe formation scenarios and the possibility of additional companions in the system using Gaia EDR3 and our radial velocities. 

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