The Sun in Time: Activity and Environment by Güdel Manuel

“…The Sun's magnetic activity has steadily declined during its main-sequence life. While the solar photospheric luminosity was about 30% lower 4.6 Gyr ago when the Sun arrived on the main sequence compared to present-day levels, its faster rotation generated enhanced magnetic activity; magnetic heating processes in the chromosphere, the transition region, and the corona induced ultraviolet, extreme-ultraviolet, and X-ray emission about 10, 100, and 1000 times, respectively, the present-day levels, as inferred from young solar-analog stars. …”
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Data-driven modeling of solar coronal magnetic field evolution and eruptions by Chaowei Jiang, Xueshang Feng, Yang Guo, Qiang Hu

“…Because of a lack of direct measurements, the 3D coronal magnetic fields are commonly studied using numerical modeling, whereas traditional models mostly aim for a static extrapolation of the coronal field from the observable photospheric magnetic field data. Over the last decade, dynamic models that are driven directly by observation magnetograms have been developed and applied successfully to study solar coronal magnetic field evolution as well as its eruption, which offers a novel avenue for understanding their underlying magnetic topology and mechanism. …”
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A Possible Correlation between Metallicity and Near-IR Color for Late-M and L Dwarfs by Ruihan Zhang, Michael C. Liu, Zhoujian Zhang

“…We assess the correlation between the Δ( J − K ) color anomaly (the difference in an object’s J − K color from the median color for field objects of the same spectral type) and the metallicity of the host star to investigate how metallicity affects ultracool photospheres. Using Spearman’s rank correlation test and Student’s t-test, the late-M dwarf (L dwarf) sample’s Δ( J − K ) and metallicity show a positive correlation at the 95% (90%) confidence level. …”
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Mass Transfer in Two Post-AGB Binaries with Dusty Disks by Gorlova N., Van Winckel H., Jorissen A.

“…In addition, strong photospheric lines reveal a narrow central absorption. …”
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The FIP and Inverse FIP Effects in Solar and Stellar Coronae by J. Martin Laming

“…These effects relate to the enhancement or depletion, respectively, in coronal abundance with respect to photospheric values of elements with FIP below about 10 eV. …”
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Ground-based follow-up observations of TRAPPIST-1 transits in the near-infrared by Burdanov, AY, Lederer, SM, Gillon, M, Delrez, L, Ducrot, E, de Wit, J, Jehin, E, Triaud, AHMJ, Lidman, C, Spitler, L, Demory, B-O, Queloz, D, Van Grootel, V

“…A possible obstacle to this technique could come from the photospheric heterogeneity of the host star that could affect planetary signatures in the transit transmission spectra. …”
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The local galaxy 8 μm luminosity function by Huang, J, Ashby, M, Barmby, P, Brodwin, M, Brown, M, Caldwell, N, Cool, R, Eisenhardt, P, Eisenstein, D, Fazio, G, Le Floc'h, E, Green, P, Kochanek, C, Lu, N, Pahre, M, Rigopoulou, D, Rosenberg, J, Smith, H, Wang, Z, Willmer, C, Willner, S

“…Dust emission (mostly PAH) accounts for 80% of the 8 μm luminosity, stellar photospheres account for 19%, and AGN emission accounts for roughly 1%. …”

Separating planetary reflex Doppler shifts from stellar variability in the wavelength domain by Cameron, AC, Ford, EB, Shahaf, S, Aigrain, S, Dumusque, X, Haywood, RD, Mortier, A, Phillips, DF, Buchhave, L, Cecconi, M, Cegla, H, Cosentino, R, Cretignier, M, Ghedina, A, Gonzalez, M, Latham, DW, Lodi, M, Lopez-Morales, M, Micela, G, Molinari, E, Pepe, F, Piotto, G, Poretti, E, Queloz, D, Juan, JS, Segransan, D, Sozzetti, A, Szentgyorgyi, A, Thompson, S, Udry, S, Watson, C

“…Stellar magnetic activity produces time-varying distortions in the photospheric line profiles of solar-type stars. These lead to systematic errors in high-precision radial-velocity measurements, which limit efforts to discover and measure the masses of low-mass exoplanets with orbital periods of more than a few tens of days. …”

The Local Galaxy 8 micron Luminosity Function by Huang, J, Ashby, M, Barmby, P, Brodwin, M, Brown, M, Caldwell, N, Cool, R, Eisenhardt, P, Eisenstein, D, Fazio, G, Floc'h, E, Green, P, Kochanek, C, Lu, N, Pahre, M, Rigopoulou, D, Rosenberg, J, Smith, H, Wang, Z, Willmer, C, Willner, S

“…Dust emission (mostly PAH) accounts for 80% of the 8 micron luminosity, stellar photospheres account for 19%, and AGN emission accounts for roughly 1 %. …”

The UV/optical spectra of the Type Ia supernova SN 2010jn: a bright supernova with outer layers rich in iron-group elements by Hachinger, S, Mazzali, P, Sullivan, M, Ellis, R, Maguire, K, Gal-Yam, A, Howell, D, Nugent, P, Baron, E, Cooke, J, Arcavi, I, Bersier, D, Dilday, B, James, P, Kasliwal, M, Kulkarni, SR, Ofek, E, Laher, R, Parrent, J, Surace, J, Yaron, O, Walker, E

“…SN 2010jn was discovered by the Palomar Transient Factory (PTF) 15 d before maximum light, allowing us to secure a time series of four near-UV spectra at epochs from -10.5 to +4.8 d relative to B-band maximum. The photospheric near-UV spectra are excellent diagnostics of the iron-group abundances in the outer layers of the ejecta, particularly those at very early times. …”

Alfvénic Motions Arising from Asymmetric Acoustic Wave Drivers in Solar Magnetic Structures by Samuel J. Skirvin, Yuhang Gao, Tom Van Doorsselaere

“…Alfvénic motions are ubiquitous in the solar atmosphere and their observed properties are closely linked to those of photospheric p-modes. However, it is still unclear how a predominantly acoustic wave driver can produce these transverse oscillations in the magnetically dominated solar corona. …”
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Role of Small-scale Impulsive Events in Heating the X-Ray Bright Points of the Quiet Sun by Biswajit Mondal, James A Klimchuk, Santosh V. Vadawale, Aveek Sarkar, Giulio Del Zanna, P. S. Athiray, N. P. S. Mithun, Helen E. Mason, Anil Bhardwaj

“…The lengths and magnetic field strengths of these loops are obtained through a potential field extrapolation of the photospheric magnetogram. Each loop is assumed to be heated by random nanoflares having an energy that depends on the loop properties. …”
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Type W and Type 15bn Subgroups of Hydrogen-poor Superluminous Supernovae: Premaximum Diversity, Postmaximum Homogeneity? by Réka Könyves-Tóth, Bálint Seli

“…It is concluded that in terms of photospheric temperature and velocity, Type W and Type 15bn SLSNe-I decrease to a similar value by the postmaximum phases, and their pseudo-nebular spectra are nearly uniform. …”
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Examining the Source Regions of Solar Energetic Particles Using an AI-generated Synchronic Potential Field Source Surface Model by Jinhye Park, Hyun-Jin Jeong, Yong-Jae Moon

“…By comparing the AI _HMI , HMI, Global Oscillations Network Group (GONG) synoptic magnetograms, and Air force Data Assimilative Photospheric flux Transport synchronic magnetograms, as well as the PFSS extrapolations, we find interesting differences between them in view of SEP source regions and magnetic field configurations. …”
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The Merging of a Coronal Dimming and the Southern Polar Coronal Hole by Nawin Ngampoopun, David M. Long, Deborah Baker, Lucie M. Green, Stephanie L. Yardley, Alexander W. James, Andy S. H. To

“…The plasma dynamics are quantified using spectroscopic data obtained from the EUV Imaging Spectrometer on board Hinode. The photospheric magnetograms from the Helioseismic and Magnetic Imager are used to derive the magnetic field properties. …”
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Data-constrained Solar Modeling with GX Simulator by Gelu M. Nita, Gregory D. Fleishman, Alexey A. Kuznetsov, Sergey A. Anfinogentov, Alexey G. Stupishin, Eduard P. Kontar, Samuel J. Schonfeld, James A. Klimchuk, Dale E. Gary

“…The package includes a fully automatic model production pipeline that, based on minimal users input, downloads the required SDO/HMI vector magnetic field data, performs potential or nonlinear force-free field extrapolations, populates the magnetic field skeleton with parameterized heated plasma coronal models that assume either steady-state or impulsive plasma heating, and generates non-LTE density and temperature distribution models of the chromosphere that are constrained by photospheric measurements. The standardized models produced by this pipeline may be further customized through specialized IDL scripts, or a set of interactive tools provided by the graphical user interface. …”
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The Solar Minimum Eclipse of 2019 July 2. III. Inferring the Coronal T e with a Radiative Differential Emission Measure Inversion by Benjamin Boe, Cooper Downs, Shadia Habbal

“…This radiative-DEM (R-DEM) inversion utilizes visible and infrared emission lines that are excited by photospheric radiation out to at least 3 R _⊙ . Specifically, we use the Fe x (637 nm), Fe xi (789 nm), and Fe xiv (530 nm) coronal emission lines observed during the 2019 July 2 TSE near solar minimum. …”
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Spicules in IRIS Mg ii Observations: Automated Identification by Vicki L. Herde, Phillip C. Chamberlin, Don Schmit, Souvik Bose, Adrian Daw, Ryan O. Milligan, Vanessa Polito

“…We present event statistics and relate occurrence rates to the underlying photospheric magnetic field strength. This method identifies spicule event densities and occurrence rates similar to previous studies performed using H α and Ca ii observations of active regions. …”
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Early-time Ultraviolet and Optical Hubble Space Telescope Spectroscopy of the Type II Supernova 2022wsp by Sergiy S. Vasylyev, Christian Vogl, Yi Yang, Alexei V. Filippenko, Thomas G. Brink, Peter J. Brown, Thomas Matheson, Maryam Modjaz, Avishay Gal-Yam, Paolo A. Mazzali, Thomas de Jaeger, Kishore C. Patra, Gabrielle E. Stewart

“…The early-time evolution of the photospheric velocity and temperature derived from the modeling agree with the behavior observed from other previously studied cases. …”
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Toward Robust Atmospheric Retrieval on Cloudy L Dwarfs: the Impact of Thermal and Abundance Profile Assumptions by Melanie J. Rowland, Caroline V. Morley, Michael R. Line

“…Near-infrared (NIR) spectra probe a limited range of pressures, while many species condense within their photospheres. Condensation creates two complexities: gas-phase species “rain out” (decreasing in abundances by many orders of magnitude) and clouds form. …”
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