Search Publications
The HD 98800 quadruple pre-main sequence system. Towards full orbital characterisation using long-baseline infrared interferometry
Bayo, A.; Olofsson, J.; Haubois, X. +8 more
Context. HD 98800 is a young (∼10 Myr old) and nearby (∼45 pc) quadruple system, composed of two spectroscopic binaries orbiting around each other (AaAb and BaBb), with a gas-rich disk in polar configuration around BaBb. While the orbital parameters of BaBb and AB are relatively well constrained, this is not the case for AaAb. A full characterisat…
Dissecting the Supercritical Filaments Embedded in the 0.5 pc Subsonic Region of Barnard 5
Caselli, Paola; Pineda, Jaime E.; Arce, Héctor G. +7 more
We characterize in detail the two ∼0.3 pc long filamentary structures found within the subsonic region of Barnard 5. We use combined Robert C. Byrd Green Bank Telescope and Very Large Array observations of the molecular lines NH3(1,1) and (2,2) at a resolution of 1800 au, as well as James Clerk Maxwell Telescope continuum observations a…
Extended Tidal Tails of IC 4756 Detected by Gaia EDR3
Zhao, Gang; Yang, Yong; Ye, Xianhao +2 more
We report the discovery of emerged tidal tails around open cluster IC 4756 (~1 Gyr) based on 644 members identified from Gaia EDR3. Three-dimensional spatial positions and two-dimensional tangential velocities $\left(x,y,z,\kappa \cdot {\mu }_{\alpha }^{* }/\varpi ,\kappa \cdot {\mu }_{\delta }/\varpi \right)$ are utilized to determine the comovin…
Study of the hydrogen escape rate at Mars during martian years 28 and 29 from comparisons between SPICAM/Mars express observations and GCM-LMD simulations
Lopez-Valverde, M. A.; Forget, F.; Montmessin, F. +10 more
We have simulated the 3D atomic hydrogen density in the Martian upper atmosphere and associated Jeans escape rate during Martian years 28 and 29. The coronal Lyman-α brightness is computed using a 3D radiative transfer model which accounts for the monthly average hydrogen density for these two years and is compared to a large set of observations b…
The McDonald Accelerating Stars Survey (MASS): White Dwarf Companions Accelerating the Sun-like Stars 12 Psc and HD 159062
Cochran, William D.; Endl, Michael; Kratter, Kaitlin M. +7 more
We present the discovery of a white dwarf companion to the G1 V star 12 Psc found as part of a Keck adaptive optics imaging survey of long-term accelerating stars from the McDonald Observatory Planet Search Program. Twenty years of precise radial-velocity monitoring of 12 Psc with the Tull Spectrograph at the Harlan J. Smith telescope reveals a mo…
The Photospheric Footpoints of Solar Coronal Hole Jets
Muglach, K.
We study the photospheric footpoints of a set of 35 coronal jets in a coronal hole as observed by Hinode/EIS. We use SDO/AIA data to coalign the spectroscopic EIS data with SDO/HMI line-of-sight magnetograms and calculate the plane-of-sky flow field using local correlation tracking (LCT) on SDO/HMI white light images. The jets are put into categor…
Cosmic Evolution of Barred Galaxies up to z 0.84
Park, Myeong-Gu; Ann, Hong Bae; Sheth, Kartik +4 more
We explore the cosmic evolution of the bar length, strength, and light deficit around the bar for 379 barred galaxies at 0.2 < z ≤ 0.835 using F814W images from the COSMOS survey. Our sample covers galaxies with stellar masses $10.0\leqslant \mathrm{log}({M}_{* }/{M}_{\odot })\leqslant 11.4$ and various Hubble types. The bar length is strongly …
Press-Schechter primordial black hole mass functions and their observational constraints
Padilla, Nelson D.; Magaña, Juan; Sureda, Joaquín +1 more
We present a modification of the Press-Schechter (PS) formalism to derive general mass functions for primordial black holes (PBHs), considering their formation as being associated with the amplitude of linear energy density fluctuations. To accommodate a wide range of physical relations between the linear and non-linear conditions for collapse, we…
Discovery of a New Redback Millisecond Pulsar Candidate: 4FGL J0940.3-7610
Strader, Jay; Dage, Kristen C.; Chomiuk, Laura +3 more
We have discovered a new candidate redback millisecond pulsar binary near the center of the error ellipse of the bright unassociated Fermi-LAT γ-ray source 4FGL J0940.3-7610. The candidate counterpart is a variable optical source that also shows faint X-ray emission. Optical photometric and spectroscopic monitoring with the SOAR telescope indicate…
X-Ray Emission from the PeVatron-candidate Supernova Remnant G106.3+2.7
Matsumoto, Hironori; Bamba, Aya; Fujita, Yutaka +1 more
We report the discovery of diffuse X-ray emission around the supernova remnant (SNR) G106.3+2.7, which is associated with VER J2227+608 and HAWC J2227+610 and is known as a candidate for a PeV cosmic-ray accelerator (PeVatron). We analyze observational data of Suzaku around the SNR and the adjacent pulsar PSR J2229+6114. We find diffuse X-ray emis…