Search Publications
Could the Magnetic Star HD 135348 Possess a Rigidly Rotating Magnetosphere?
Gagliano, Robert; Jayaraman, Rahul; Ricker, George R. +5 more
We report the detection and characterization of a new magnetospheric star, HD 135348, based on photometric and spectropolarimetric observations. The TESS light curve of this star exhibited variations consistent with stars known to possess rigidly rotating magnetospheres (RRMs), so we obtained spectropolarimetric observations using the Robert Stobi…
Luminosity Function and Event Rate Density of XMM-Newton-selected Supernova Shock Breakout Candidates
Liu, Zhu; Yuan, Weimin; Sun, Hui +6 more
A dozen X-ray supernova shock breakout (SN SBO) candidates were reported recently based on XMM-Newton archival data, which increased the X-ray-selected SN SBO sample by an order of magnitude. Assuming that they are genuine SN SBOs, we study the luminosity function (LF) by improving on the method used in our previous work. The light curves and the …
Light from the Darkness: Detecting Ultra-diffuse Galaxies in the Perseus Cluster through Over-densities of Globular Clusters with a Log-Gaussian Cox Process
van Dokkum, Pieter; Romanowsky, Aaron J.; Abraham, Roberto +6 more
We introduce a new method for detecting ultra-diffuse galaxies by searching for over-densities in intergalactic globular cluster populations. Our approach is based on an application of the log-Gaussian Cox process, which is a commonly used model in the spatial statistics literature but rarely used in astronomy. This method is applied to the globul…
The Solar Wind Parker Spiral Angle Distributions and Variations at 1 au
Xu, Qi; Xu, Xiaojun; Wang, Jing +8 more
Using the data from the Advanced Composition Explorer (ACE) and Wind spacecraft, we statistically studied the Parker spiral angle (PSA) of the solar wind magnetic field from 1998 to 2019 at 1 au. The PSA occurrences over both a Carrington rotation (CR) and a year can be well fitted by a Gaussian distribution. However, large-scale magnetic structur…
Searching Extra-tidal Features around the Globular Cluster Whiting 1
Tian, Haijun; Tian, Hao; Carballo-Bello, Julio A. +14 more
Whiting 1 is a faint and young globular cluster in the halo of the Milky Way, and was suggested to have originated in the Sagittarius spherical dwarf galaxy (Sgr dSph). In this paper, we use the deep DESI Legacy Imaging Surveys to explore tentative spatial connection between Whiting 1 and the Sgr dSph. We redetermine the fundamental parameters of …
The Astrometric Animation of Water Masers toward the Mira Variable BX Cam
Kim, Dong-Jin; Sun, Yan; Orosz, Gabor +20 more
We report very long baseline interferometry (VLBI) monitoring observations of the 22 GHz water (H2O) masers around the Mira variable BX Cam, which were carried out as a part of the EAVN Synthesis of Stellar Maser Animations project. Data of 37 epochs in total were obtained from 2018 May to 2021 June with a time interval of 3-4 weeks, sp…
High-latitude Observations of Inertial-range Turbulence by the Ulysses Spacecraft During the Solar Minimum of 1993-96
Isenberg, Philip A.; Schwadron, Nathan A.; Murphy, Neil +8 more
We have examined Ulysses magnetic field measurements for the years 1993 through 1996 as the spacecraft moved sunward from 5 au at high southern latitudes, passing through perihelion during the first fast-latitude scan to achieve high northern latitudes, and finally returning to 5 au. These years represent near-solar-minimum activity, providing a c…
Distances to Local Group Galaxies via Population II, Stellar Distance Indicators. II. The Fornax Dwarf Spheroidal
Madore, Barry F.; Freedman, Wendy L.; Cerny, William +5 more
We determine three independent Population II distance moduli to the Fornax dwarf spheroidal (dSph) galaxy, using wide-field, ground-based VI imaging acquired with the Magellan-Baade telescope at Las Campanas Observatory. After subtracting foreground stars using Gaia EDR3 proper motions, we measure an I-band tip of the red giant branch (TRGB) magni…
On the Characterization of GJ 504: A Magnetically Active Planet-host Star Observed by the Transiting Exoplanet Survey Satellite (TESS)
Stassun, Keivan G.; García, Rafael A.; Corsaro, Enrico +11 more
We present the results of the analysis of the photometric data collected in long- and short-cadence mode by the Transiting Exoplanet Survey Satellite for GJ 504, a well-studied planet-hosting solar-like star, whose fundamental parameters have been largely debated during the last decade. Several attempts have been made by the present authors to iso…
Using Multiple Emission Line Ratios to Constrain the Slope of the Dust Attenuation Law
Papovich, Casey; Cleri, Nikko J.; Trump, Jonathan R. +2 more
We explore the possibility and practical limitations of using a three-line approach to measure both the slope and normalization of the dust attenuation law in individual galaxies. To do this, we focus on a sample of 11 galaxies with existing ground-based Balmer Hα and Hβ measurements from slit spectra, plus space-based grism constraints on Paschen…