Publications (20)
Million-Degree Plasma Pervading the Extended Orion Nebula
M. Guedel, K. R. Briggs, T. Montmerle +3
Most stars form as members of large associations within dense, very cold (10-100 K) molecular clouds. The nearby giant molecular cloud in Orion hosts several thousand stars of ages…
An X-rays Survey of the Young Stellar Population of the Lynds 1641 and Iota Orionis Regions
I. Pillitteri, S. J. Wolk, S. T. Megeath +12
We present an XMM-Newton survey of the part of Orion A cloud south of the Orion Nebula. This survey includes the Lynds 1641 (L1641) dark cloud, a region of the Orion A cloud with v…
Circumstellar Disks in the Outer Galaxy: the Star-Forming Region NGC 1893
M. Caramazza, G. Micela, L. Prisinzano +3
It is still debated whether star formation process depends on environment. In particular it is yet unclear whether star formation in the outer Galaxy, where the environmental condi…
The lithium-rotation connection in the 125 Myr-old Pleiades cluster
J. Bouvier, D. Barrado, E. Moraux +9
The evolution of lithium abundance over a star's lifetime is indicative of transport processes operating in the stellar interior. We revisit the relationship between lithium conten…
New insights on the near-infrared veiling of young stars using CFHT/SPIRou data
A. P. Sousa, J. Bouvier, S. H. P. Alencar +10
Veiling is ubiquitous at different wavelength ranges in accreting stars. However, the origin of the veiling in the IR domain is not well understood. The accretion spot alone is not…
CSI 2264: Simultaneous optical and X-ray variability in pre-Main Sequence stars. I: Time resolved X-ray spectral analysis during optical dips and accretion bursts in stars with disks
M. G. Guarcello, E. Flaccomio, G. Micela +6
Pre-main sequence stars are variable sources. In stars with disks, this variability is related to the morphology of the inner circumstellar region (<0.1 AU) and that of the photosp…
The circumstellar environment of the young, low-mass dipper star JH 223. Accretion and large-scale magnetic field topology
T. P. Freitas, J. Bouvier, B. Zaire +11
Studies of magnetospheric accretion and magnetic field topology in T Tauri stars have advanced over the years, but their applications to fully convective, very-low-mass T Tauri sta…
Long period modulation of the classical T Tauri star CI Tau: evidence for an eccentric close-in massive planet at 0.17 au
R. Manick, A. P. Sousa, J. Bouvier +13
Detecting planets within protoplanetary disks around young stars is essential for understanding planet formation and evolution. However, planet detection using the radial velocity…
CSI2264: Simultaneous optical and X-ray variability in the pre-main sequence stars of NGC2264. II: Photometric variability, magnetic activity, and rotation in classIII objects and stars with transition disks
M. G. Guarcello, E. Flaccomio, G. Micela +6
Pre-main sequence stars are variable sources. In diskless stars this variability is mainly due to the rotational modulation of dark photospheric spots and active regions, as in mai…
The large-scale disk fraction of brown dwarfs in the Taurus cloud as measured with Spitzer
J. -L. Monin, S. Guieu, C. Pinte +14
Aims. The brown dwarf (BD) formation process has not yet been completely understood. To shed more light on the differences and similarities between star and BD formation processes,…
Magnetospheric accretion in the intermediate-mass T Tauri star HQ Tau
K. Pouilly, J. Bouvier, E. Alecian +7
Context. Classical T Tauri stars (cTTs) are pre-main sequence stars surrounded by an accretion disk. They host a strong magnetic field, and both magnetospheric accretion and ejecti…
The X-ray activity-rotation relation of T Tauri stars in Taurus-Auriga
K. R. Briggs, M. Guedel, A. Telleschi +9
The Taurus-Auriga star-forming complex hosts the only population of T Tauri stars in which an anticorrelation of X-ray activity and rotation period has been observed. We have used…
Mid-Infrared Variability of protostars in IC 1396A
M. Morales-Calderon, J. R. Stauffer, L. Rebull +7
We have used Spitzer/IRAC to conduct a photometric monitoring program of the IC1396A dark globule in order to study the mid-IR (3.6 - 8 micron) variability of the heavily embedded…
A multi-wavelength view of magnetic flaring from PMS stars
E. Flaccomio, G. Micela, S. Sciortino +5
Flares from the Sun and other stars are most prominently observed in the soft X-ray band. Most of the radiated energy, however, is released at optical/UV wavelengths. In spite of d…
A Sensitive Search for Variability in Late L Dwarfs: The Quest for Weather
M. Morales-Calderon, J. R. Stauffer, J. Davy Kirkpatrick +10
We have conducted a photometric monitoring program of 3 field late-L brown dwarfs looking for evidence of non-axisymmetric structure or temporal variability in their photospheres.…
Accretion and Outflow-Related X-Rays in T Tauri Stars
M. Guedel, K. Briggs, K. Arzner +22
We report on accretion- and outflow-related X-rays from T Tauri stars, based on results from the "XMM-Newton Extended Survey of the Taurus Molecular Cloud." X-rays potentially form…
The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)
M. Guedel, K. R. Briggs, K. Arzner +18
(abridged:) The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) surveys the most populated ~5 square degrees of the Taurus star formation region, using the XMM-Newt…
Spitzer Observations of G Dwarfs in the Pleiades: Circumstellar Debris Disks at 100 Myr Age
J. R. Stauffer, L. Rebull, J. Carpenter +12
Fluxes and upper limits in the wavelength range from 3.6 to 70 microns from the Spitzer Space Telescope are provided for twenty solar-mass Pleiades members. One of these stars show…
A Model for (Quasi-)Periodic Multi-wavelength Photometric Variability in Young Stellar Objects
Aurora Y. Kesseli, Maya A. Petkova, Kenneth Wood +7
We present radiation transfer models of rotating young stellar objects (YSOs) with hotspots in their atmospheres, inner disk warps and other 3-D effects in the nearby circumstellar…
X-ray properties of protostars in the Orion Nebula
L. Prisinzano, G. Micela, E. Flaccomio +8
The origin and evolution of the X-rays in very young stellar objects (YSOs) are not yet well understood since it is very hard to observe YSOs in the protostellar phase. We study th…