Search Publications
JWST/NIRCam Coronagraphy of the Young Planet-hosting Debris Disk AU Microscopii
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…
Relation between metallicities and spectral energy distributions of Herbig Ae/Be stars. A potential link with planet formation
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…
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
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…
The evolving paradigm of the subauroral geospace
Mishin, Evgeny V.
An assessment of the status quo of fast subauroral flows—subauroral ion drifts (SAID) and subauroral polarization streams (SAPS), is presented. For a few decades, their development has been interpreted in terms of the voltage and current magnetospheric generators based largely on the drift motion of test particles. Recent multispacecraft observati…
A T-dwarf candidate from JWST early release NIRCam data
Hashimoto, Tetsuya; Goto, Tomotsugu; Kim, Seong Jin +6 more
We present a distant T-type brown dwarf candidate at ≈2.55 kpc discovered in the Cosmic Evolution Early Release Science (CEERS) fields by JWST NIRCam. In addition to the superb sensitivity, we utilized seven filters from JWST in near-infrared and thus is advantageous in finding faint, previously unseen brown dwarfs. From the model spectra in new J…
Progress on nuclear reaction rates affecting the stellar production of 26Al
Meynet, G.; Diehl, R.; Vink, J. S. +24 more
The radioisotope 26Al is a key observable for nucleosynthesis in the Galaxy and the environment of the early Solar System. To properly interpret the large variety of astronomical and meteoritic data, it is crucial to understand both the nuclear reactions involved in the production of 26Al in the relevant stellar sites and the…
Star Formation and AGN Activity 500 Myr after the Big Bang: Insights from JWST
D'Silva, Jordan C. J.; Driver, Simon P.; Lagos, Claudia D. P. +3 more
We consider the effect of including an active galactic nuclei (AGN) component when fitting spectral energy distributions of 109 spectroscopically confirmed z ≈ 3.5-12.5 galaxies with JWST. Remarkably, we find that the resulting cosmic star formation history is ≈0.4 dex lower at z ≳ 9.5 when an AGN component is included in the fitting. This allevia…
Matter ejections behind the highs and lows of the transitional millisecond pulsar PSR J1023+0038
Covino, S.; D'Avanzo, P.; Campana, S. +23 more
Transitional millisecond pulsars are an emerging class of sources that link low-mass X-ray binaries to millisecond radio pulsars in binary systems. These pulsars alternate between a radio pulsar state and an active low-luminosity X-ray disc state. During the active state, these sources exhibit two distinct emission modes (high and low) that altern…
The AstroSat UV Deep Field North: The Far- and Near-ultraviolet Photometric Catalog
Teplitz, Harry I.; Rafelski, Marc; Saha, Kanak +7 more
We present deep UV imaging observations of the Great Observatories Origins Survey Northern (GOODS-N) field with AstroSat/UVIT (AstroSat UV Deep Field north-AUDFn), using one far-UV (FUV) (F154W, 34.0 ks) and two near-UV (NUV) filters (N242W, 19.2 ks; N245M, 15.5 ks). The nature of the UV sky background was explored across the UVIT field, and a glo…
A compact multi-planet system transiting HIP 29442 (TOI-469) discovered by TESS and ESPRESSO. Radial velocities lead to the detection of transits with low signal-to-noise ratio
Bouchy, F.; Rebolo, R.; Zapatero Osorio, M. R. +52 more
Context. One of the goals of the Echelle Spectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) Guaranteed Time Observations (GTO) consortium is the precise characterisation of a selected sample of planetary systems discovered by TESS. One such target is the K0V star HIP 29442 (TOI-469), already known to host a validate…