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1. Parker Solar Probe Enters the Magnetically Dominated Solar Corona

   https://doi.org/10.1103/PhysRevLett.127.255101  

   Kasper, J. C.; Klein, K. G.; Lichko, E.; Huang, Jia; Chen, C. H. K.; Badman, S. T.; Bonnell, J.; Whittlesey, P. L.; Livi, R.; Larson, D.; et al (December 2021, Physical Review Letters)
2. Solar Cycle and Solar Wind Dependence of the Occurrence of Large dB / dt Events at High Latitudes

   https://doi.org/10.1029/2022JA030953  

   Milan, S. E.; Imber, S. M.; Fleetham, A. L.; Gjerloev, J. (April 2023, Journal of Geophysical Research: Space Physics)

   Key Points Large dB / dt “spikes” in ground magnetometer data occur in three local time hotspots in the pre‐midnight, dawn, and pre‐noon sectors These are consistent with spikes produced by substorm onsets, omega bands, and the Kelvin‐Helmholtz instability, respectively Spike occurrence is controlled by solar activity, maximizing in the declining phase of the solar cycle, esp. solar cycle 23 

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3. Predicting the Solar Wind at the Parker Solar Probe Using an Empirically Driven MHD Model

   https://doi.org/10.3847/1538-4365/ab58c9  

   Kim, T. K.; Pogorelov, N. V.; Arge, C. N.; Henney, C. J.; Jones-Mecholsky, S. I.; Smith, W. P.; Bale, S. D.; Bonnell, J. W.; Dudok de Wit, T.; Goetz, K.; et al (February 2020, The Astrophysical Journal Supplement Series)
4. Properties of carbon stars in the solar neighbourhood based on Gaia DR2 astrometry

   https://doi.org/10.1051/0004-6361/201936831  

   Abia, C.; de Laverny, P.; Cristallo, S.; Kordopatis, G.; Straniero, O. (January 2020, Astronomy & Astrophysics)

   Context. Stars evolving along the asymptotic giant branch (AGB) can become carbon rich in the final part of their evolution. The detailed description of their spectra has led to the definition of several spectral types: N, SC, J, and R. To date, differences among them have been partially established only on the basis of their chemical properties. Aims. An accurate determination of the luminosity function (LF) and kinematics together with their chemical properties is extremely important for testing the reliability of theoretical models and establishing on a solid basis the stellar population membership of the different carbon star types. Methods. Using Gaia Data Release 2 ( Gaia DR2) astrometry, we determine the LF and kinematic properties of a sample of 210 carbon stars with different spectral types in the solar neighbourhood with measured parallaxes better than 20%. Their spatial distribution and velocity components are also derived. Furthermore, the use of the infrared Wesenheit function allows us to identify the different spectral types in a Gaia -2MASS diagram. Results. We find that the combined LF of N- and SC-type stars are consistent with a Gaussian distribution peaking at M bol  ∼ −5.2 mag. The resulting LF, however, shows two tails at lower and higher luminosities more extended than those previously found, indicating that AGB carbon stars with solar metallicity may reach M bol  ∼ −6.0 mag. This contrasts with the narrower LF derived in Galactic carbon Miras from previous studies. We find that J-type stars are about half a magnitude fainter on average than N- and SC-type stars, while R-hot stars are half a magnitude brighter than previously found, although fainter in any case by several magnitudes than other carbon types. Part of these differences are due to systematically lower parallaxes measured by Gaia DR2 with respect to H IPPARCOS values, in particular for sources with parallax ϖ < 1 mas. The Galactic spatial distribution and velocity components of the N-, SC-, and J-type stars are very similar, while about 30% of the R-hot stars in the sample are located at distances greater than ∼500 pc from the Galactic plane, and show a significant drift with respect to the local standard of rest. Conclusions. The LF derived for N- and SC-type in the solar neighbourhood fully agrees with the expected luminosity of stars of 1.5−3 M ⊙ on the AGB. On a theoretical basis, the existence of an extended low-luminosity tail would require a contribution of extrinsic low-mass carbon stars, while the high-luminosity tail would imply that stars with mass values up to ∼5 M ⊙ may become carbon stars on the AGB. J-type stars differ significantly not only in their chemical composition with respect to the N- and SC-types, but also in their LF, which reinforces the idea that these carbon stars belong to a different type whose origin is still unknown. The derived luminosities of R-hot stars means that it is unlikely that these stars are in the red-clump, as previously claimed. On the other hand, the derived spatial distribution and kinematic properties, together with their metallicity values, indicate that most of the N-, SC-, and J-type stars belong to the thin disc population, while a significant fraction of R-hot stars show characteristics compatible with the thick disc. 

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5. Rotation and magnetic activity of oscillating solar-like stars with the Kepler mission

   https://doi.org/10.1051/epjconf/201715205011  

   Mathur, Savita; Balliet, Lauren; García, Rafael A.; Salabert, David; Catelan, M.; Gieren, W. (January 2017, EPJ Web of Conferences)