Search Publications
UVIT Survey of the Host Galaxies of Active Galactic Nuclei. I. Star Formation Scenarios
Stalin, C. S.; Nandi, Payel; Saikia, D. J. +1 more
Circumnuclear star formation (SF) is generally seen in galaxies hosting active galactic nuclei (AGN); however, the connection between the AGN activity and SF in them is less well understood. To explore this connection on scales of a few tens of parsecs to a few tens of kiloparsecs and larger, we carried out an investigation of SF in seven Seyfert-…
A New Rarity Assessment of the "Disk of Satellites": The Milky Way System Is the Exception Rather Than the Rule in the ΛCDM Cosmology
Yoon, Suk-Jin; Paudel, Sanjaya; Moon, Jun-Sung +2 more
The majority of satellite galaxies around the Milky Way (MW) show disk-like distributions (the disk of satellites; DoS), which is a small-scale problem of the lambda cold dark matter cosmology. The conventional definition of the MW-like DoS is a satellite system with a minor-to-major axis ratio (c/a) lower than the MW's c/a value of 0.181. Here, w…
The Dark Energy Camera Magellanic Clouds Emission-line Survey
White, Richard L.; Rest, Armin; Blair, William P. +7 more
We have used the Dark Energy Camera (DECam) on the CTIO Blanco 4 m telescope to perform a new emission-line survey of the Large Magellanic Cloud (LMC) using narrowband Hα and [S II] filters in addition to a continuum band to create pure emission-line images. We refer to this new survey as DeMCELS, to distinguish it from the earlier Magellanic Clou…
Boron Abundances in Early B Dwarfs of the Galactic Open Cluster NGC 3293
Cunha, Katia; Langer, Norbert; Proffitt, Charles R. +4 more
New boron abundances or upper limits have been determined for eight early B stars in the young Galactic open cluster NGC 3293, using UV spectra obtained by the Hubble Space Telescope Cosmic Origins Spectrograph. With previous observations, there are now 18 early B stars in this cluster with boron measurements. Six of the newly observed stars have …
Asteroseismology of One of the Most Rapidly Rotating DBV Stars: EPIC 248705247
Su, Jie; Cang, Tianqi; Fu, Jianning +4 more
We present a comprehensive analysis of oscillations of the helium-rich white dwarf DBV star EPIC 248705247 (SDSS J102106.69+082724.8). We extract the light curves from 79.7 days of K2 Campaign 14 data and identify 21 independent frequencies, including three complete and three incomplete dipole modes, with an average frequency splitting of 20.37 ± …
Direct Observations of a Shock Traversing Preceding Two Coronal Mass Ejections: Insights from Solar Orbiter, Wind, and STEREO Observations
Zhang, Zhiyong; Wang, Yuming; Shen, Chenglong +8 more
The three successive coronal mass ejections (CMEs) that erupted from 2023 November 27–28, provide the first opportunity to shed light on the entire process of a shock propagating through, sequentially compressing, and modifying two preceding CMEs using in situ data from Solar Orbiter, Wind, and STEREO-A. We describe the interaction of the three CM…
Precise Mass, Orbital Motion, and Stellar Properties of the M-dwarf Binary LP 349‑25AB
Curiel, Salvador; Ortiz-León, Gisela N.; Mioduszewski, Amy J. +1 more
LP 349‑25 is a well-studied close stellar binary system comprised of two late M dwarf stars, where both stars are close to the limit between star and brown dwarf. This system was previously identified as a source of gigahertz radio emission. We observed LP 349‑25AB over 11 epochs in 2020–2022, detecting both components in this nearby binary system…
Temporally Resolved Type III Solar Radio Bursts in the Frequency Range 3–13 MHz
Maksimovic, Milan; Kontar, Eduard P.; Chrysaphi, Nicolina +2 more
Radio observations from space allow to characterize solar radio bursts below the ionospheric cutoff, which are otherwise inaccessible, but suffer from low, insufficient temporal resolution. In this Letter we present novel, high-temporal resolution observations of type III solar radio bursts in the range 3–13 MHz. A dedicated configuration of the R…
Investigating 56 High Galactic Latitude Open Cluster Candidates in Gaia DR3
Chen, Jing; Zhang, Su; Wu, You +4 more
Using Gaia DR3 data, we revisit 56 high Galactic latitude (∣b∣ ≥ 30°) open cluster (OC) candidates with poor shapes of color–magnitude diagrams (CMDs), including unclear and paired main sequences (MSs). We aim to confirm their physical reality and explore whether the special MS morphology is intrinsic to genuine OCs. Initially, we redetermine clus…
Assessment of SDSS-derived Galaxy Morphologies Using HST Imaging
Salim, Samir; Osborne, Chandler
The Sloan Digital Sky Survey (SDSS) was foundational to the study of galaxy evolution, having revealed the bimodality of galaxies and the relationship between their structure and star-forming activity. However, ground-based optical surveys like SDSS are limited in resolution and depth, which may lead to biases or poor quality in the derived morpho…