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1. Galactic Gas Flows from Halo to Disk: Tomography and Kinematics at the Milky Way’s Disk–Halo Interface

   https://doi.org/10.3847/1538-4357/ab3414  

   Bish, Hannah V.; Werk, Jessica K.; Prochaska, J. Xavier; Rubin, Kate H.; Zheng, Yong; O’Meara, John M.; Deason, Alis J. (September 2019, The Astrophysical Journal)

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2. The Strikingly Metal-rich Halo of the Sombrero Galaxy

   https://doi.org/10.3847/1538-4357/ab64e9  

   Cohen, Roger E.; Goudfrooij, Paul; Correnti, Matteo; Gnedin, Oleg Y.; Harris, William E.; Chandar, Rupali; Puzia, Thomas H.; Sánchez-Janssen, Rubén (February 2020, The Astrophysical Journal)
3. The Galaxy–Halo Connection in Low-mass Halos

   https://doi.org/10.3847/2041-8213/aafe80  

   Feldmann, Robert; Faucher-Giguère, Claude-André; Kereš, Dušan (February 2019, The Astrophysical Journal)
4. Nitrogen-interrupted halo -Prins/ halo -Nazarov fragment coupling cascade for the synthesis of indolines

   https://doi.org/10.1039/d3sc00986f  

   Milosavljevic, Aleksa; Holt, Connor; Frontier, Alison J. (May 2023, Chemical Science)

   The nitrogen-interrupted Nazarov cyclization can be a powerful method for the stereocontrolled synthesis of sp 3 -rich N -heterocycles. However, due to the incompatibility between the basicity of nitrogen and the acidic reaction conditions, examples of this type of Nazarov cyclization are scarce. Herein, we report a one-pot nitrogen-interrupted halo -Prins/ halo -Nazarov coupling cascade that joins two simple building blocks, an enyne and a carbonyl partner, to furnish functionalized cyclopenta[ b ]indolines with up to four contiguous stereocenters. For the first time, we provide a general method for the alkynyl halo -Prins reaction of ketones, thus enabling the formation of quaternary stereocenters. Additionally, we describe the outcomes of secondary alcohol enyne couplings, which exhibit helical chirality transfer. Furthermore, we investigate the impact of aniline enyne substituents on the reaction and evaluate the tolerance of different functional groups. Finally, we discuss the reaction mechanism and demonstrate various transformations of the prepared indoline scaffolds, highlighting their applicability in drug discovery campaigns. 

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5. A Tilt in the Dark Matter Halo of the Galaxy

   https://doi.org/10.3847/1538-4357/ac795f  

   Han, Jiwon Jesse; Naidu, Rohan P.; Conroy, Charlie; Bonaca, Ana; Zaritsky, Dennis; Caldwell, Nelson; Cargile, Phillip; Johnson, Benjamin D.; Chandra, Vedant; Speagle, Joshua S.; et al (July 2022, The Astrophysical Journal)

   Abstract Recent observations of the stellar halo have uncovered the debris of an ancient merger, Gaia–Sausage–Enceladus (GSE), estimated to have occurred ≳8 Gyr ago. Follow-up studies have associated GSE with a large-scale tilt in the stellar halo that links two well-known stellar overdensities in diagonally opposing octants of the Galaxy (the Hercules–Aquila Cloud and Virgo Overdensity; HAC and VOD). In this paper, we study the plausibility of such unmixed merger debris persisting over several gigayears in the Galactic halo. We employ the simulated stellar halo from Naidu et al., which reproduces several key properties of the merger remnant, including the large-scale tilt. By integrating the orbits of these simulated stellar halo particles, we show that adoption of a spherical halo potential results in rapid phase mixing of the asymmetry. However, adopting a tilted halo potential preserves the initial asymmetry in the stellar halo for many gigayears. The asymmetry is preserved even when a realistic growing disk is added to the potential. These results suggest that HAC and VOD are long-lived structures that are associated with GSE and that the dark matter halo of the Galaxy is tilted with respect to the disk and aligned in the direction of HAC–VOD. Such halo–disk misalignment is common in modern cosmological simulations. Lastly, we study the relationship between the local and global stellar halo in light of a tilted global halo comprised of highly radial orbits. We find that the local halo offers a dynamically biased view of the global halo due to its displacement from the Galactic center. 

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