Results 21 to 30 of about 801 (259)
Interaction Of A Stellar Magnetic Field With A Turbulent Accretion Disk [PDF]
International Astronomical Union Colloquium, 1997 AbstractMagnetized objects surrounded by a turbulent and keplerian accretion disk are considered. In such systems, magnetic field lines are embedded into the disk. The magnetic field of the central object is assumed to be dipolar in the absence of the accretion disk.
Anne Bardou, Jean Heyvaerts
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On the Accretion Origin of a Vast Extended Stellar Disk around the Andromeda Galaxy [PDF]
The Astrophysical Journal, 2005 We present the discovery of an inhomogenous, low-surface brightness, extended disk-like structure around the Andromeda galaxy (M31) based on a large kinematic survey of more than 2800 stars with the Keck/DEIMOS spectrograph. The stellar structure spans radii from 15 kpc out to ~40 kpc, with detections out to R ~ 70 kpc.
Ibata, R +5 more
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The Astrophysical Journal, 2023 Strong iron lines are a common feature of the optical spectra of active galactic nuclei (AGNs) and quasars from z ∼ 6−7 to the local universe, and [Fe/Mg] ratios do not show cosmic evolution.
Jian-Min Wang +8 more
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Properties of Circum(sub)stellar Accretion Disks
, 2002 We have completed a systematic survey for disks around young brown dwarfs and very low mass stars. By choosing a well-defined sample and by obtaining sensitive thermal IR observations, we can make an unbiased measurement of the disk fraction around such low mass objects.
Liu, Michael C. +2 more
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Ionization and heating by X-rays and cosmic rays*
EPJ Web of Conferences, 2015 High-energy radiation from the central T Tauri and protostars plays an important role in shaping protoplanetary disks and influences their evolution. Such radiation, in particular X-rays and extreme-ultraviolet (EUV) radiation, is predominantly generated
Güdel Manuel
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LAMOST Reveals Long-lived Protoplanetary Disks
The Astronomical JournalWhile both observations and theories demonstrate that protoplanetary disks are not expected to live much longer than ∼10 Myr, several examples of prolonged disks have been observed in the past.
Xiao-Long Wang +4 more
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Stellar Growth by Disk Accretion: The Effect of Disk Irradiation on the Protostellar Evolution
The Astrophysical Journal, 2008 Young stars are expected to gain most of their mass by accretion from a disk that forms around them as a result of angular momentum conservation in the collapsing protostellar cloud. Accretion initially proceeds at high rates of 10^{-6}-10^{-5} M_Sun/yr resulting in strong irradiation of the stellar surface by the hot inner portion of the disk and ...
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Hyperosmotic stress induces PARP1‐mediated HPF1‐dependent mono(ADP‐ribosyl)ation
FEBS Letters, EarlyView.Sorbitol‐induced hyperosmotic stress rapidly induces reversible mono(ADP‐ribosyl)ation (MARylation) on PARP1 without the signs of genotoxic signaling. We show that PARP1 autoMARylation is HPF1 dependent and forms hydroxylamine‐resistant O‐glycosidic linkages.
Anna Georgina Kopasz +11 more
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Understanding Balmer Decrements in T Tauri Stars in Terms of Multiflow Magnetospheric Accretion
The Astrophysical JournalMagnetospheric accretion is the paradigm for accretion in classical T Tauri stars (CTTSs). However, the standard, one-flow magnetospheric accretion model fails to replicate important characteristics such as the observed Balmer decrements. We address this
Naiara Patiño +6 more
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The Disks and Accretion Behavior of Young Stellar Objects [PDF]
, 2011 Zirkumstellare Scheiben spielen eine entscheidende Rolle im Prozess der Sternentstehung und gelten darüberhinaus als die Geburtsstätten neuer Planetensysteme. Notwendig zum Verständnis der Planetenund Sternentstehung ist daher das Wissen um die Entwicklung zirkumstellarer Akkretionsscheiben in Abhängigkeit von der stellaren Umgebung.
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