Preparing for the Early eVolution Explorer: Photometric Diagnostics of Magnetospheric Accretion Geometry in…

Abstract

The inner disk truncation radius, R_T, plays a crucial role in the regulation of star-disk interaction and the early evolution of star-disk-planet systems; however, measuring this parameter is observationally challenging. We present a new method for determining R_T in young accreting systems that hinges on the color dependence of the accretion shock emission in multi-band time-domain surveys. Based on the accretion simulations of Robinson et al. (2017, 2021), we produce synthetic color-magnitude diagrams at near-UV and optical wavelengths that predict the loci of accreting stars as a function of R_T. We test these model predictions on young stars with interferometric R_T estimates, finding very good agreement in our results. We apply this novel technique to a pilot survey of 26 classical T Tauri stars in Taurus and Upper Scorpius. We find a predominance of sources with small truncation radii, R_T < 4 R_⋆, and an overall distribution of R_T that is statistically similar to that inferred from interferometric studies, while differing from those inferred from emission line modeling. Finally, we discuss the application of this technique to NASA's mission concept EVE, with the goal to provide simultaneous measurements of inner disk truncation radii, corotation radii and mass accretion rates for hundreds of young stars across the Galaxy. The unprecedented survey of inner disk properties that the mission would produce would enable the first stringent test of angular momentum evolution theories in young stars and reveal the impact of the inner disk conditions on early planet architectures.

3D simulations of magnetospheric accretion in T Tauri stars I. Disk truncation, stellar torques, and application to observations
G. Pantolmos, C. Zanni, J. Bouvier
Astronomy & Astrophysics9 Oct 2026Peer-reviewedPublisher termsSolar & stellar physicsCrossref
3D simulations of magnetospheric accretion in T Tauri stars: I. Disk truncation, stellar torques, and application to observations
George Pantolmos, Claudio Zanni, Jérôme Bouvier
arXiv5 Oct 2026PreprintarXiv licenceFull textSolar & stellar physicsarXiv
Unstable magnetospheric accretion on the T Tauri star TW Hya
J.-F. Donati, P. Cristofari, C. Moutou +9
Astronomy & Astrophysics - A&A22 Sep 2026Peer-reviewedCC BY 4.0Full textSolar & stellar physicsHAL
Dynamical evolution and surface accretion of DART impact ejecta in the (65803) Didymos system
X. Fu, N. Stronati, S. Soldini +6
Astronomy & Astrophysics27 Oct 2026Peer-reviewedPublisher termsPlanetary science & exoplanetsCrossref
The long-term evolution of a black hole accretion torus: a comparison between GRMHD simulations and relativistic thin disk theory
Andrew Mummery, Minghao Guo, Eliot Quataert +1
arXiv26 Oct 2026PreprintCC BY 4.0Full textHigh-energy astrophysicsarXiv

Cite

BibTeX RIS

BibTeX

@misc{venuti2026preparing,
  title = {{Preparing for the Early eVolution Explorer: Photometric Diagnostics of Magnetospheric Accretion Geometry in Young Stellar Objects}},
  author = {Laura Venuti and Connor E. Robinson and Ann Marie Cody and Eric Gaidos and Meredith A. MacGregor and Neal J. Turner and Mark R. Swain and George Zhou and Sydney Vach and Lukas Gehrig and Christopher M. Johns-Krull and Zhaohuan Zhu and Jennifer A. Burt and Ward S. Howard and Damon Landau and Evgenya Shkolnik},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2608.23351},
  eprint = {2608.23351},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2608.23351},
  note = {CC BY 4.0},
}

RIS

TY  - UNPB
TI  - Preparing for the Early eVolution Explorer: Photometric Diagnostics of Magnetospheric Accretion Geometry in Young Stellar Objects
AU  - Laura Venuti
AU  - Connor E. Robinson
AU  - Ann Marie Cody
AU  - Eric Gaidos
AU  - Meredith A. MacGregor
AU  - Neal J. Turner
AU  - Mark R. Swain
AU  - George Zhou
AU  - Sydney Vach
AU  - Lukas Gehrig
AU  - Christopher M. Johns-Krull
AU  - Zhaohuan Zhu
AU  - Jennifer A. Burt
AU  - Ward S. Howard
AU  - Damon Landau
AU  - Evgenya Shkolnik
PY  - 2026
DA  - 2026/09/14
PB  - arXiv
DO  - 10.48550/arxiv.2608.23351
UR  - https://arxiv.org/abs/2608.23351
AB  - The inner disk truncation radius, R_T, plays a crucial role in the regulation of star-disk interaction and the early evolution of star-disk-planet systems; however, measuring this parameter is observationally challenging. We present a new method for determining R_T in young accreting systems that hinges on the color dependence of the accretion shock emission in multi-band time-domain surveys. Based on the accretion simulations of Robinson et al. (2017, 2021), we produce synthetic color-magnitude diagrams at near-UV and optical wavelengths that predict the loci of accreting stars as a function of R_T. We test these model predictions on young stars with interferometric R_T estimates, finding very good agreement in our results. We apply this novel technique to a pilot survey of 26 classical T Tauri stars in Taurus and Upper Scorpius. We find a predominance of sources with small truncation radii, R_T < 4 R_⋆, and an overall distribution of R_T that is statistically similar to that inferred from interferometric studies, while differing from those inferred from emission line modeling. Finally, we discuss the application of this technique to NASA's mission concept EVE, with the goal to provide simultaneous measurements of inner disk truncation radii, corotation radii and mass accretion rates for hundreds of young stars across the Galaxy. The unprecedented survey of inner disk properties that the mission would produce would enable the first stringent test of angular momentum evolution theories in young stars and reveal the impact of the inner disk conditions on early planet architectures.
ER  -

Abstract

Related

Cite