Results 81 to 90 of about 206 (176)

VLT/MUSE Detection of Accretion/Ejection Associated with the Close Stellar Companion in the HT Lup System

The Astrophysical Journal
The accretion/ejection processes in T Tauri stars are fundamental to their physical evolution, while also impacting the properties and evolution of the circumstellar material at a time when planet formation takes place.
Sebastián Jorquera, Mickaël Bonnefoy, Laura M. Pérez, Gaël Chauvin, Adrian Aguinaga, Catherine Dougados, Rémi Julo, Dorian Demars, Sean M. Andrews, Luca Ricci, Zhaohuan Zhu, Nicolas T. Kurtovic, Nicolás Cuello, Xue-Ning Bai, Til Birnstiel, Cornellis Dullemond, Viviana V. Guzmán   +16 more
doaj   +1 more source

Evidence of a Disk Wind Origin for Fluorescent H2 in Classical T Tauri Stars

The Astronomical Journal
We use far-ultraviolet spectra of 36 T Tauri stars, predominately from the Hubble Space Telescope (HST) ULLYSES program, to examine the kinematic properties of fluorescent H _2 emission lines for evidence of disk outflows.
Matt Kalscheur, Kevin France, Brunella Nisini, P. Christian Schneider, Richard Alexander, Jochen Eislöffel, Justyn Campbell-White, Hsien Shang, Manuele Gangi, Zhen Guo, Seok-Jun Chang   +10 more
doaj   +1 more source

A Critique of Current Magnetic‐Accretion Models for Classical T Tauri Stars [PDF]

The Astrophysical Journal, 1998
Current magnetic-accretion models for classical T-Tauri stars rely on a strong, dipolar magnetic field of stellar origin to funnel the disk material onto the star, and assume a steady-state. In this paper, I critically examine the physical basis of these models in light of the observational evidence and our knowledge of magnetic fields in low-mass ...
openaire   +2 more sources

Measuring the Magnetic Field of the Classical T Tauri Star TW Hydrae

The Astrophysical Journal, 2005
We present infrared (IR) and optical echelle spectra of the Classical T Tauri star TW Hydrae. Using the optical data, we perform detailed spectrum synthesis to fit atomic and molecular absorption lines and determine key stellar parameters: Teff = 4126 \pm 24 K, log g = 4.84 \pm 0.16, [M/H] = -0.10 \pm 0.12, vsini = 5.8 \pm 0.6 km/s.
Yang, H., Johns-Krull, C. M., Valenti, J. A.   +2 more
openaire   +2 more sources

A Multiwavelength, Multiepoch Monitoring Campaign of Accretion Variability in T Tauri Stars from the ODYSSEUS Survey. II. Photometric Light Curves

The Astrophysical Journal
Classical T Tauri stars (CTTSs) are young, low-mass stars that accrete material from their surrounding protoplanetary disk. To better understand accretion variability, we conducted a multiepoch, multiwavelength photometric monitoring campaign of four ...
John Wendeborn, Catherine C. Espaillat, Thanawuth Thanathibodee, Connor E. Robinson, Caeley V. Pittman, Nuria Calvet, Ágnes Kóspál, Konstantin N. Grankin, Fredrick M. Walter, Zhen Guo, Jochen Eislöffel   +10 more
doaj   +1 more source

ExoplaNeT accRetion mOnitoring sPectroscopic surveY (ENTROPY)

Astronomy & Astrophysics
Context. Observations of helium emission lines from classical T Tauri stars at high resolution (Rλ > 10 000) offer great potential, showing distinct profile characteristics that help probe regions within the accretion geometry untapped by hydrogen lines.
Viswanath Gayathri, Bonnefoy Mickaël, Dougados Catherine, Ringqvist Simon C., Janson Markus, Demars Dorian, Sicilia-Aguilar Aurora, Bouvier Jérôme, Marleau Gabriel-Dominique, Alecian Evelyne, Chauvin Gaël   +10 more
doaj   +1 more source

Outflows from the youngest stars are mostly molecular. [PDF]

Nature, 2023
Ray TP, McCaughrean MJ, Caratti O Garatti A, Kavanagh PJ, Justtanont K, van Dishoeck EF, Reitsma M, Beuther H, Francis L, Gieser C, Klaassen P, Perotti G, Tychoniec L, van Gelder M, Colina L, Greve TR, Güdel M, Henning T, Lagage PO, Östlin G, Vandenbussche B, Waelkens C, Wright G.   +22 more
europepmc   +1 more source

Monitoring the magnetospheric accretion of the classical T Tauri star DO Tau with SPIRou

Astronomy & Astrophysics
We present observations of the classical T Tauri star DO Tau collected with the near-infrared SPIRou spectropolarimeter and precision velocimeter at the Canada-France-Hawaii Telescope from early 2020 to late 2025.
Donati J.-F., Cristofari P. I., Carmona A., Lavail A., Moutou C., Bouvier J., Perraut K., Alencar S. H. P., Ménard F., Audard M., Petit P., Alecian E., Ray T.   +12 more
doaj   +1 more source

Haro 5-2: A New Pre-main-sequence Quadruple Stellar System

The Astronomical Journal
We have discovered that the H α emission-line star Haro 5-2, located in the 3–6 Myr old Ori OB1b association, is a young quadruple system. The system has a 2+2 configuration, with an outer separation of 2.″6 and with resolved subarcsecond inner binary ...
Bo Reipurth, C. Briceño, T. R. Geballe, C. Baranec, S. Mikkola, A. M. Cody, M. S. Connelley, C. Flores, B. A. Skiff, J. D. Armstrong, N. M. Law, R. Riddle   +11 more
doaj   +1 more source

Warm Disk Coronae in Classical T Tauri Stars

The Astrophysical Journal, 1997
It is proposed that a warm disk corona is a characteristic feature of the accretion process in a classical T Tauri star, based on analyses of the [O I] λλ6300, 5577 emission and the central absorptions in the Balmer lines of hydrogen. Calculations are presented to determine the physical conditions needed to produce the hydrogen and O I excitation. They
openaire   +1 more source