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TOI-199 b: A Well-characterized 100 day Transiting Warm Giant Planet with TTVs Seen from Antarctica
DOI: 10.3847/1538-3881/acfc1d Bibcode: 2023AJ....166..201H

Trifonov, Trifon; Henning, Thomas; Latham, David W. +49 more

We present the spectroscopic confirmation and precise mass measurement of the warm giant planet TOI-199 b. This planet was first identified in TESS photometry and confirmed using ground-based photometry from ASTEP in Antarctica including a full 6.5 hr long transit, PEST, Hazelwood, and LCO; space photometry from NEOSSat; and radial velocities (RVs…

2023 The Astronomical Journal
Gaia 12
Improving the selection of changing-look AGNs through multiwavelength photometric variability
DOI: 10.1093/mnras/stad1893 Bibcode: 2023MNRAS.524..188L

Stern, D.; Salvato, M.; Merloni, A. +13 more

We present second epoch optical spectra for 30 changing-look (CL) candidates found by searching for Type-1 optical variability in a sample of active galactic nuclei (AGNs) spectroscopically classified as Type 2. We use a random-forest-based light-curve classifier and spectroscopic follow-up, confirming 50 per cent of candidates as turning-on CLs. …

2023 Monthly Notices of the Royal Astronomical Society
XMM-Newton 12
Low-ionization structures in planetary nebulae - II. Densities, temperatures, abundances, and excitation of six PNe
DOI: 10.1093/mnras/stac2729 Bibcode: 2023MNRAS.518.3908M

Gonçalves, Denise R.; Akras, Stavros; Mari, M. Belén

Here we present the spatially resolved study of six Galactic planetary nebulae (PNe), namely IC 4593, Hen 2-186, Hen 2-429, NGC 3918, NGC 6543, and NGC 6905, from intermediate-resolution spectra of the 2.5 m Isaac Newton Telescope and the 1.54 m Danish telescope. The physical conditions (electron densities, Ne, and temperatures, Te…

2023 Monthly Notices of the Royal Astronomical Society
eHST 12
3D chemical structure of the diffuse turbulent interstellar medium. II. The origin of CH+: A new solution to an 80-year mystery
DOI: 10.1051/0004-6361/202243902 Bibcode: 2023A&A...669A..74G

Godard, B.; Hennebelle, P.; Pineau des Forêts, G. +2 more


Aims: The high abundances of CH+ in the diffuse interstellar medium (ISM) are a long-standing issue of our understanding of the thermodynamical and chemical states of the gas. We investigate here the formation of CH+ in turbulent and multiphase environments, where the heating of the gas is almost solely driven by the photoelectric …

2023 Astronomy and Astrophysics
Gaia 12
Saturn's Atmosphere in Northern Summer Revealed by JWST/MIRI
DOI: 10.1029/2023JE007924 Bibcode: 2023JGRE..12807924F

Fletcher, Leigh N.; Hedman, Matthew M.; Guerlet, Sandrine +8 more

Saturn's northern summertime hemisphere was mapped by JWST/Mid-Infrared Instrument (4.9-27.9 µm) in November 2022, tracing the seasonal evolution of temperatures, aerosols, and chemical species in the 5 years since the end of the Cassini mission. The spectral region between reflected sunlight and thermal emission (5.1-6.8 µm) is mapped for the fir…

2023 Journal of Geophysical Research (Planets)
eHST JWST 12
Raising the observed metallicity floor with a 3D non-LTE analysis of SDSS J102915.14+172927.9
DOI: 10.1051/0004-6361/202245786 Bibcode: 2023A&A...672A..90L

Hansen, T. T.; Amarsi, A. M.; Lind, K. +4 more

Context. The first stars marked the end of the cosmic dark ages, produced the first heavy elements, and set the stage for the formation of the first galaxies. Accurate chemical abundances of ultra metal-poor stars ([Fe/H] < −4) can be used to infer the properties of the first stars and thus the formation mechanism for low-mass second-generation…

2023 Astronomy and Astrophysics
Gaia 12
Revised orbits of the two nearest Jupiters
DOI: 10.1093/mnras/stad2297 Bibcode: 2023MNRAS.525..607F

Butler, R. Paul; Vogt, Steven S.; Holden, Bradford +2 more

With its near-to-mid-infrared high-contrast imaging capabilities, JWST is ushering us into a golden age of directly imaging Jupiter-like planets. As the two closest cold Jupiters, ɛ Ind A b and ɛ Eridani b have sufficiently wide orbits and adequate infrared emissions to be detected by JWST. To detect more Jupiter-like planets for direct imaging, w…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 12
JWST/NIRCam Coronagraphy of the Young Planet-hosting Debris Disk AU Microscopii
DOI: 10.3847/1538-3881/aced08 Bibcode: 2023AJ....166..150L

Barclay, Thomas; Young, Erick T.; Boccaletti, Anthony +20 more

High-contrast imaging of debris disk systems permits us to assess the composition and size distribution of circumstellar dust, to probe recent dynamical histories, and to directly detect and characterize embedded exoplanets. Observations of these systems in the infrared beyond 2-3 µm promise access to both extremely favorable planet contrast…

2023 The Astronomical Journal
Gaia eHST JWST 12
Relation between metallicities and spectral energy distributions of Herbig Ae/Be stars. A potential link with planet formation
DOI: 10.1051/0004-6361/202245427 Bibcode: 2023A&A...671A.140G

Montesinos, B.; Mendigutía, I.; Kama, M. +5 more

Context. Most studies devoted to Herbig Ae/Be stars (HAeBes) assume solar metallicity. However, the stellar metallicity, [M/H], is a fundamental parameter that can strongly differ depending on the source and may have important implications for planet formation. It has been proposed that the deficit of refractory elements observed in the surfaces o…

2023 Astronomy and Astrophysics
Gaia 12
Testing the evolutionary pathways of galaxies and their supermassive black holes and the impact of feedback from active galactic nuclei via large multiwavelength data sets
DOI: 10.1093/mnras/stac3211 Bibcode: 2023MNRAS.518.2088M

Mountrichas, George; Shankar, Francesco

It is still a matter of intense debate how supermassive black holes (SMBHs) grow and the role played by feedback from active galactic nuclei (AGN) in the coevolution of SMBHs and galaxies. To test the coevolution proposed by theoretical models, we compile a large AGN sample of 5639 X-ray detected AGN, over a wide redshift range, spanning nearly th…

2023 Monthly Notices of the Royal Astronomical Society
Herschel 12