Multi-epoch observations with high spatial resolution of multiple T Tauri systems

Csépány, G.; Ancker, M. E. van den; Ábrahám, P.; Köhler, Rainer H.; Brandner, W.; Hormuth, F.; Hiss, Hector

doi:10.1051/0004-6361/201527494

Cited by 14 publications

(9 citation statements)

References 110 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The absorption column density is low and not well-constrained by the Chandra spectra. Thus, it was held fixed during fitting at N H = 2 × 10 21 cm −2 , compatible with A V = 1.1 (+0.4,−0.2) mag for XZ Tau A (Csépány et al 2017) and similar to values determined from previous XMM-Newton observations.…”

Section: Xz Taumentioning

confidence: 56%

X-Ray Emission and Disk Irradiation of HL Tau and HD 100546

Skinner

Güdel

2019

ApJ

View full text Add to dashboard Cite

We present new X-ray observations of the optically-obscured protostar HL Tau and the intermediate mass Herbig Be star HD 100546. Both objects are surrounded by spectacular disks showing complex morphology including rings and gaps that may have been sculpted by protoplanets. HL Tau was detected as a variable hard X-ray source by Chandra, typical of late-type magnetically-active coronal sources. No extended X-ray emission was seen along the HL Tau jet, or along the jet of the T Tauri binary system XZ Tau located 23 ′′ to its east. In contrast, HD 100546 was detected by XMM-Newton as a soft X-ray source (kT < ∼ 1 keV) with no short-term (<1 day) variability. Its X-ray properties are remarkably similar to the Herbig stars AB Aur and HD 163296, strongly suggesting that their X-ray emission arises from the same mechanism and is intrinsic to the Herbig stars themselves, not due to unseen late-type companions. We consider several possible emission mechanisms and conclude that the X-ray properties of HD 100546 are consistent with an accretion shock origin, but higher resolution grating spectra capable of providing information on individual emission lines are needed to more reliably distinguish between accretion shocks and alternatives. We show that X-ray ionization and heating are mainly confined to the upper disk layers in both HL Tau and HD 100546, and any exoplanets near the midplane at distances ≥1 au are well-shielded from X-rays produced by the central star. 2The X-ray luminosity of low and intermediate mass PMS stars is typically in the range L x ∼ 10 28 -10 31 ergs s −1 , about 10 1 -10 4 times that of the quiet Sun. As young solar-like stars age and spin down, their X-ray luminosity declines (Güdel, Guinan, & Skinner 1997). Stellar X-rays heat and ionize disk gas and the gaseous atmospheres of any close-in protoplanets, and must be taken into account in realistic models of planet formation. X-ray ionization of disk gas also promotes the magnetorotational instability (Balbus & Hawley 1991) and can thereby affect accretion onto the central star.In magnetically-active class I protostars obscured by surrounding envelopes and optically-revealed T Tauri stars (TTS), very high plasma temperatures (T ∼ 100 MK) can be reached during powerful short-duration (minutes to hours) magnetic reconnection flares. In addition to flash-heating, such flares can produce high energy particles that bombard the inner disk and any close-in protoplanets (reviewed by Feigelson & Montmerle 1999; Feigelson 2010).The photoelectric cross section for absorption of X-rays by gas scales inversely with photon energy as σ ∝ E −p , where p ≈ 2.5 for solar-abundance gas. Soft X-rays (E < ∼ 1 keV) are thus heavily absorbed in outer disk layers, whereas harder X-rays with energies of several keV penetrate deeper and can potentially reach the disk midplane, as can cosmic rays. As a young star evolves and its inner disk gas disperses, close-in protoplanets become more heavily exposed to stellar X-rays. Detailed discussions of X-ray heating and ionization ...

show abstract

Section: Xz Taumentioning

confidence: 56%

X-Ray Emission and Disk Irradiation of HL Tau and HD 100546

Skinner

Güdel

2019

ApJ

View full text Add to dashboard Cite

show abstract

“…Recently, Gaia measured the separation to be 1.4863±0.0006 (Gaia Collaboration et al 2016). Using a large compilation of data from the literature, Csépány et al (2017) determined that RW Aur A and B are currently moving away from each other at about 3.6 mas yr −1 (see their Tables 2 and 5); accounting for this increase in separation puts our observations in excellent agreement with the HST data of Ghez et al (1997), and with the other accurate separation measurements obtained in the meantime with VLT/NACO (Correia et al 2006), CHANDRA (Skinner & Güdel 2014), and Gaia (Gaia Collaboration et al 2016).…”

Section: Continuum Modelingmentioning

confidence: 99%

Multiple Stellar Flybys Sculpting the Circumstellar Architecture in RW Aurigae

Rodriguez

Loomis

Cabrit

et al. 2018

ApJ

View full text Add to dashboard Cite

We present high-resolution ALMA Band 6 and 7 observations of the tidally disrupted protoplanetary disks of the RW Aurigae binary. Our observations reveal the presence of additional tidal streams to the previously observed tidal arm around RW Aur A. The observed configuration of tidal streams surrounding RW Aur A and B is incompatible with a single star-disk tidal encounter, suggesting that the RW Aurigae system has undergone multiple fly-by interactions. We also resolve the circumstellar disks around RW Aur A and B, with CO radii of 58 au and 38 au consistent with tidal truncation, and 2.5 times smaller dust emission radii. The disks appear misaligned by 12 • or 57 • . Using new photometric observations from the American Association of Variable Star Observers (AAVSO) and All Sky Automated Survey for SuperNovae (ASAS-SN) archives, we have also identified an additional dimming event of the primary that began in late 2017 and is currently ongoing. With over a century of photometric observations, we are beginning to explore the same spatial scales as ALMA.

show abstract

“…RW Aur is a young visual binary (Joy & van Biesbroeck 1944) with the current separation between the components of about 1.5 arcsec (Bisikalo et al 2012;Gaia Collaboration et al 2016;Csépány et al 2017). The primary of the system RW Aur A is a classical T Tauri star, i.e.…”

Section: Introductionmentioning

confidence: 99%

Analysis of colour and polarimetric variability of RW Aur A in 2010–2018

Dodin

Grankin

Ламзин

et al. 2018

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

Results of U BV RIJHKLM photometry and V RI polarimetry of a young star RW Aur A observed during unprecedented long and deep (up to ∆V ≈ 5 mag) dimming events in 2010-11 and 2014-18 are presented. The polarization degree p of RW Aur A at this period has reached 30 per cent in the I band. As in the case of UX Ori type stars (UXORs), the so-called 'bluing effect' in the colour-magnitude V versus V − R c , V − I c diagrams of the star and a strong anticorrelation between p and brightness were observed. But the duration and the amplitude of the eclipses as well as the value and orientation of polarization vector in our case differ significantly from that of UXORs. We concluded that the dimmings of RW Aur A occurred due to eclipses of the star and inner regions of its disc by the axisymmetric dust structure located above the disc and created by the disc wind. Taking into account both scattering and absorption of stellar light by the circumstellar dust, we explain some features of the light curve and the polarization degree -magnitude dependence. We found that near the period of minimal brightness mass-loss rate of the dusty wind was > 10 −9 M ⊙ yr −1 .

show abstract

Multi-epoch observations with high spatial resolution of multiple T Tauri systems

Cited by 14 publications

References 110 publications

X-Ray Emission and Disk Irradiation of HL Tau and HD 100546

X-Ray Emission and Disk Irradiation of HL Tau and HD 100546

Multiple Stellar Flybys Sculpting the Circumstellar Architecture in RW Aurigae

Analysis of colour and polarimetric variability of RW Aur A in 2010–2018

Contact Info

Product

Resources

About