Search Publications
Millisecond Pulsars in Dense Star Clusters: Evolution, Scaling Relations, and the Galactic-center Gamma-Ray Excess
Ye, Claire S.; Fragione, Giacomo
The number of millisecond pulsars (MSPs) observed in Milky Way globular clusters has increased explosively in recent years, but the underlying population is still uncertain due to observational biases. We use state-of-the-art N-body simulations to study the evolution of MSP populations in dense star clusters. These cluster models span a wide range…
The Effect of Molecular Cloud Properties on the Kinematics of Stars Formed in the Trifid Region
Gromadzki, Mariusz; Feigelson, Eric D.; Hillenbrand, Lynne A. +5 more
The dynamical states of molecular clouds may affect the properties of the stars they form. In the vicinity of the Trifid Nebula (d = 1180 ± 25 pc), the main star cluster (Trifid Main) lies within an expanding section of the molecular cloud; however, ~0.°3 to the north (Trifid North), the cloud's velocity structure is more tranquil. We acquired a C…
Chandra Observations of Six Peter Pan Disks: Diversity of X-Ray-driven Internal Photoevaporation Rates Does Not Explain Their Rare Longevity
Kounkel, Marina; Kuchner, Marc J.; Wisniewski, John P. +6 more
We present Chandra X-ray observations of six previously identified Peter Pan objects, rare ∼40 Myr systems with evidence of primordial disk retention. We observe X-ray luminosities (0.8–3.0 keV) ranging from log L x ∼ 27.7–29.1. We find that our Peter Pan sample exhibits X-ray properties similar to that of weak-lined T Tauri stars and…
Spatial Structures in the Globular Cluster Distribution of Fornax Cluster Galaxies
Zezas, Andreas; Fabbiano, Giuseppina; Paolillo, Maurizio +3 more
We report the discovery of statistically significant spatial structures in the projected two-dimensional distributions of Globular Cluster (GC) systems of 10 galaxies that are among the brightest in the Fornax Cluster. We use a catalog of GCs extracted from the Hubble Space Telescope Advanced Camera for Surveys Fornax Cluster Survey imaging data. …
A Comprehensive Study of the Young Cluster IRAS 05100+3723: Properties, Surrounding Interstellar Matter, and Associated Star Formation
Zavagno, A.; Samal, M. R.; Ojha, D. K. +13 more
We present a comprehensive multiwavelength investigation of a likely massive young cluster "IRAS 05100+3723" and its environment with the aim to understand its formation history and feedback effects. We find that IRAS 05100+3723 is a distant (~3.2 kpc), moderate-mass (~500 M ⊙), young (~3 Myr) cluster with its most massive star being an…
The Magnetic Field Environment of Active Region 12673 That Produced the Energetic Particle Events of September 2017
Green, Lucie M.; Yardley, Stephanie L.; Mihailescu, Teodora +2 more
Forecasting solar energetic particles (SEPs), and identifying flares/coronal mass ejections (CMEs) from active regions (ARs) that will produce SEP events in advance is extremely challenging. We investigate the magnetic field environment of AR 12673, including the AR's magnetic configuration, the surrounding field configuration in the vicinity of t…
Morpho-kinematic Modeling of the Expanding Ejecta of the Extremely Slow Nova V1280 Scorpii
Maehara, Hiroyuki; Sakon, Itsuki; Watanabe, Makoto +10 more
Knowledge of the morphology of nova ejecta is essential for fully understanding the physical processes involved in nova eruptions. We studied the 3D morphology of the expanding ejecta of the extremely slow nova V1280 Sco with a unique light curve. Synthetic line profile spectra were compared to the observed [O III] λλ4959, 5007 and [N II] λ5755 em…
Density Turbulence and the Angular Broadening of Outer Heliospheric Radio Sources at High Latitudes and in the Ecliptic Plane
Cairns, Iver H.; Adhikari, L.; Tasnim, Samira +1 more
Density irregularities are responsible for the scattering of radio waves in the solar wind and astrophysical plasmas. These irregularities significantly affect the inferred physical properties of radio sources, such as size, direction, and intensity. We present here a theory of angular broadening due to the scattering of radio waves by density irr…
Widespread 1-2 MeV Energetic Particles Associated with Slow and Narrow Coronal Mass Ejections: Parker Solar Probe and STEREO Measurements
Lugaz, Noé; Zhuang, Bin; Lario, David
Suprathermal ions in the corona are thought to serve as seed particles for large gradual solar energetic particle (SEP) events associated with fast and wide coronal mass ejections (CMEs). A better understanding of the role of suprathermal particles as seed populations for SEP events can be made by using observations close to the Sun. We study a se…
Polarization Spectrum of Near-Infrared Zodiacal Light Observed with CIBER
Shirahata, Mai; Cooray, Asantha; Matsuura, Shuji +14 more
We report the first measurement of the zodiacal light (ZL) polarization spectrum in the near-infrared between 0.8 and 1.8 µm. Using the low-resolution spectrometer on board the Cosmic Infrared Background Experiment, calibrated for absolute spectrophotometry and spectropolarimetry, we acquire long-slit polarization spectral images of the tota…