Search Publications
Missions
Journals
Publication Years
Lifetime of starspots on detached eclipsing binaries: Detecting the effects of tides on stellar activity
Zong, Weikai; Wang, Jiaxin; Pan, Yang +5 more
Context. Tidal deformation breaks the axisymmetric structure of stars, and this may affect stellar activity. This effect has been demonstrated in theoretical analyses and simulations, but it lacks observational support. In this paper, we use spot-modulated detached binaries to study the effect of tides on stellar activity. We show this effect by a…
Rotational Velocities and Radii Estimates of Low-mass Pre-main-sequence Stars in NGC 2264
Rhode, Katherine L.; Rebull, Luisa M.; Gray, Laurin M. +2 more
Investigating the angular momentum evolution of pre-main-sequence (PMS) stars provides important insight into the interactions between Sun-like stars and their protoplanetary disks, and the timescales that govern disk dissipation and planet formation. We present projected rotational velocities (v sin i values) of 254 T Tauri stars (TTSs) in the ∼3…
Dark matter search in the Perseus cluster with simultaneous analysis of Hitomi and Suzaku data
Kitamoto, Shunji; Sawada, Makoto; Tamura, Takayuki +1 more
The reported detection of a 3.5 keV emission line in the Perseus cluster, possibly originating from dark matter decay, is still under scrutiny. Despite extensive observations, the detection has not yet been confirmed, and its origin remains a topic of active debate. Most of the previous searches relied on spectroscopy with X-ray charge-coupled dev…
Long-term Evolution in Ionization of Ejecta Illuminated by Eta Carinae
Corcoran, Michael F.; Moffat, Anthony F. J.; Damineli, Augusto +6 more
Changes in the flux and spectrum of Eta Carinae (η Car) since 1900 have been attributed to the evolution of the central binary by some. Others suggest evolution in the occulting ejecta. The brightness jump in the 1940s, which coincided with the appearance of narrow forbidden emission lines, may have been caused by the clearing and ionization of in…
High-Energy Spectra of Black Hole and Neutron Star Low-Mass X-Ray Binaries
Pszota, Gábor
In the case of low-mass X-ray binaries, the companion star is often too faint for detection; therefore, there is no chance for dynamical studies to independently determine the mass of the compact object. In the absence of a mass estimate, one cannot make a distinction as to whether the binary hosts a black hole or neutron star. Therefore, the ques…
On the Influence of the Solar Wind on the Propagation of Earth-impacting Coronal Mass Ejections
Gopalswamy, Nat; Srivastava, Nandita; Kumar, Sandeep +1 more
Coronal mass ejections (CMEs) are subject to changes in their direction of propagation, tilt, and other properties as they interact with the variable solar wind. We investigated the heliospheric propagation of 15 Earth-impacting CMEs observed during 2010 April to 2018 August in the field of view (FOV) of the Heliospheric Imager (HI) on board the S…
A Tale of Three Dwarfs: Cluster-based Star Formation Histories of Blue Compact Dwarf Galaxies
Calzetti, Daniela; Whitmore, Bradley C.; Chandar, Rupali +9 more
We present a new study of the cluster populations in the blue compact dwarf galaxies (BCD) ESO185-IG13, ESO338-IG04, and Haro11, based on new and archival high-resolution images taken by the Hubble Space Telescope, and the first to probe the populations older than ≈100 Myr. BCDs are believed to experience intense bursts of star formation (includin…
X-ray occultations in active galactic nuclei: Physical properties of eclipsing clouds as part of the broad-line region cloud ensemble
Risaliti, G.; Pietrini, P.; Torricelli-Ciamponi, G.
Context. Short-term X-ray variability in active galactic nuclei (AGNs) can be explained as being due to varying X-ray absorption induced by the temporary occultation of the primary X-ray source, when moving absorbing clouds cross the line of sight to the X-ray source itself. Earlier work suggests that these absorbing clouds have physical propertie…
The near-infrared degree of polarization in debris disks. Toward a self-consistent approach to model scattered light observations
Bayo, A.; Henning, Th.; Milli, J. +2 more
Context. Debris disks provide a unique opportunity to probe the properties of small µm-sized particles, allowing us to peer into the constituents of their parent bodies, namely the young analogs of comets and the asteroids of our Solar System.
Aims: In the past, studies of the total intensity phase function - that is, the brightness of …
Observations of Uranus at High Phase Angle as Seen by New Horizons
Mayorga, L. C.; Singer, Kelsi N.; Stern, S. Alan +14 more
We present flux measurements of Uranus observed at phase angles of 43.°9, 44.°0, and 52.°4 by the Multispectral Visible Imaging Camera on the New Horizons spacecraft during 2023, 2010, and 2019, respectively. New Horizons imaged Uranus at a distance of about 24–70 au (2023) in four color filters, with bandpasses of 400–550 nm, 540–700 nm, 780–975 …