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1. LIGHTCURVES AND ROTATIONAL PERIODS OF FOUR MAIN BELT ASTERIODS

   Teer, Allan; Montgomery, Kent (April 2020, The Minor planet bulletin)

   Lightcurves and rotational periods were determined for the following four asteroids: 1120 Cannonia: 3.810 ± 0.003 h; 6801 Strekov: 6.171 ± 0.016 h; (28885) 2000 KH56: 3.326 ± 0.001 h; and 87312 Akirasuzuki: 3.0439 ± 0.0007 h. 

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2. Determining the Lightcurves and Rotational Periods of Five Main Belt Asteroids

   Ahmed, Harum; Montgomery, Kent; Cheek, Michael (April 2022, The Minor planet bulletin)

   Lightcurves and rotational periods were determined for the following five main belt asteroids: 3942 Churivannia, 2.516 ± 0.002 h; 4673 Bortle, 2.643 ± 0.001 h; 5186 Donalu, 3.154 ± 0.001 h; 8441 Lapponica, 3.285 ± 0.001 h; and 12259 Szukalski, 5.986 ± 0.001 h. 

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3. The Plutino Population: An Abundance of Contact Binaries

   https://doi.org/https://doi.org/10.3847/1538-3881/aac0ff  

   Thirouin, A; Sheppard, S.S. (May 2018, The Astronomical journal)

   We observed 12 Plutinos over two separated years with the 4.3 m Lowell’s Discovery Channel Telescope. Here, we present the first light-curve data for those objects. Three of them (2014 JL80, 2014 JO80, and 2014 JQ80) display a large light-curve amplitude explainable by a single elongated object, but they are most likely caused by a contact binary system due to their light-curve morphology. These potential contact binaries have rotational periods from 6.3 to 34.9 hr and peak-to-peak light-curve variability between 0.6 and 0.8mag. We present partial light curves, allowing us to constrain the light-curve amplitude and the rotational period of another nine Plutinos. By merging our data with the literature, we estimate that up to ∼40% of the Plutinos could be contact binaries. Interestingly, we found that all of the suspected contact binaries in the 3:2 resonance are small with absolute magnitude H>6mag. Based on our sample and the literature, up to ∼50% of the small Plutinos are potential contact binaries. 

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4. Enhancing reactivity of SiO+ ions by controlled excitation to extreme rotational states

   https://doi.org/10.1038/s41467-023-40135-x  

   Venkataramanababu, Sruthi; Li, Anyang; Antonov, Ivan O.; Dragan, James B.; Stollenwerk, Patrick R.; Guo, Hua; Odom, Brian C. (December 2023, Nature Communications)

   Abstract Optical pumping of molecules provides unique opportunities for control of chemical reactions at a wide range of rotational energies. This work reports a chemical reaction with extreme rotational excitation of a reactant and its kinetic characterization. We investigate the chemical reactivity for the hydrogen abstraction reaction SiO⁺+ H₂ → SiOH⁺+ H in an ion trap. The SiO⁺cations are prepared in a narrow rotational state distribution, including super-rotor states with rotational quantum number (j) as high as 170, using a broad-band optical pumping method. We show that the super-rotor states of SiO⁺substantially enhance the reaction rate, a trend reproduced by complementary theoretical studies. We reveal the mechanism for the rotational enhancement of the reactivity to be a strong coupling of the SiO⁺rotational mode with the reaction coordinate at the transition state on the dominant dynamical pathway. 

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5. SAMI-H  i : The H  i view of the Hα Tully–Fisher relation and data release

   https://doi.org/10.1093/mnras/stac3556  

   Catinella, Barbara; Cortese, Luca; Tiley, Alfred L.; Janowiecki, Steven; Watts, Adam B.; Bryant, Julia J.; Croom, Scott M.; d’Eugenio, Francesco; van de Sande, Jesse; Bland-Hawthorn, Joss; et al (December 2022, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT We present SAMI-H i, a survey of the atomic hydrogen content of 296 galaxies with integral field spectroscopy available from the SAMI Galaxy Survey. The sample spans nearly 4 dex in stellar mass ($$M_\star = 10^{7.4}-10^{11.1}~ \rm M_\odot$$), redshift z < 0.06, and includes new Arecibo observations of 153 galaxies, for which we release catalogues and H i spectra. We use these data to compare the rotational velocities obtained from optical and radio observations and to show how systematic differences affect the slope and scatter of the stellar-mass and baryonic Tully–Fisher relations. Specifically, we show that $$\rm H\alpha$$ rotational velocities measured in the inner parts of galaxies (1.3 effective radii in this work) systematically underestimate H i global measurements, with H i/$$\rm H\alpha$$ velocity ratios that increase at low stellar masses, where rotation curves are typically still rising and $$\rm H\alpha$$ measurements do not reach their plateau. As a result, the $$\rm H\alpha$$ stellar mass Tully–Fisher relation is steeper (when M⋆ is the independent variable) and has larger scatter than its H i counterpart. Interestingly, we confirm the presence of a small fraction of low-mass outliers of the $$\rm H\alpha$$ relation that are not present when H i velocity widths are used and are not explained by ‘aperture effects’. These appear to be highly disturbed systems for which $$\rm H\alpha$$ widths do not provide a reliable estimate of the rotational velocity. Our analysis reaffirms the importance of taking into account differences in velocity definitions as well as tracers used when interpreting offsets from the Tully–Fisher relation, at both low and high redshifts and when comparing with simulations. 

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