Search Publications
Radio Detection of an Elusive Millisecond Pulsar in the Globular Cluster NGC 6397
Fu, Xiaoting; Tsai, Chao-Wei; Freire, Paulo C. C. +32 more
We report the discovery of a new 5.78 ms period millisecond pulsar (MSP), PSR J1740-5340B (NGC 6397B), in an eclipsing binary system discovered with the Parkes radio telescope (now also known as Murriyang) in Australia and confirmed with the MeerKAT radio telescope in South Africa. The measured orbital period, 1.97 days, is the longest among all e…
Tracing Accretion onto Herbig Ae/Be Stars Using the Brγ Line
Calvet, Nuria; Espaillat, Catherine C.; Grant, Sierra L. +2 more
Accretion plays an important role in protoplanetary disk evolution, and it is thought that the accretion mechanism changes between low- and high-mass stars. Here we characterize accretion in intermediate-mass, pre-main-sequence Herbig Ae/Be (HAeBe) stars to search for correlations between accretion and system properties. We present new high-resolu…
An Old, Metal-rich Accreted Stellar Component in the Milky Way Stellar Disk
Feuillet, Diane K.; Feltzing, Sofia; Bensby, Thomas +1 more
We study the possibility that the Milky Ways' cool stellar disk includes mergers with ancient stars. Galaxies are understood to form in a hierarchical manner, where smaller (proto-)galaxies merge into larger ones. Stars in galaxies, like the Milky Way, contain in their motions and elemental abundance tracers of past events and can be used to disen…
Geminga SNR: Possible Candidate of the Local Cosmic-Ray Factory
Yuan, Qiang; Liu, Wei; Bi, Xiao-Jun +5 more
The precise measurements of energy spectra and anisotropy could help us uncover the local cosmic-ray accelerators. Our recent works have shown that spectral hardening above 200 GeV in the energy spectra and transition of large-scale anisotropy at ~100 TeV are of local source origin. Less than 100 TeV, both spectral hardening and anisotropy explici…
Charge State Calculation for Global Solar Wind Modeling
Landi, E.; van der Holst, B.; Szente, J.
The charge state composition of the solar wind carries information about the electron temperature, density, and velocity of plasma in the solar corona that cannot always be measured with remote sensing techniques, due to limitations in instrumental sensitivity and field of view as well as line-of-sight integration issues. However, in situ measurem…
Testing the Limits of AGN Feedback and the Onset of Thermal Instability in the Most Rapidly Star-forming Brightest Cluster Galaxies
McNamara, Brian R.; Donahue, Megan; Voit, G. Mark +8 more
We present new, deep, narrow- and broadband Hubble Space Telescope observations of seven of the most star-forming brightest cluster galaxies (BCGs). Continuum-subtracted [OII] maps reveal the detailed, complex structure of warm (T ~ 104 K) ionized gas filaments in these BCGs, allowing us to measure spatially resolved star formation rate…
A Simulation-driven Deep Learning Approach for Separating Mergers and Star-forming Galaxies: The Formation Histories of Clumpy Galaxies in All of the CANDELS Fields
Conselice, Christopher J.; Ferreira, Leonardo; Kuchner, Ulrike +1 more
Being able to distinguish between galaxies that have recently undergone major-merger events, or are experiencing intense star formation, is crucial for making progress in our understanding of the formation and evolution of galaxies. As such, we have developed a machine-learning framework based on a convolutional neural network to separate star-for…
SILVERRUSH. XII. Intensity Mapping for Lyα Emission Extending over 100-1000 Comoving Kpc around z 2-7 LAEs with Subaru HSC-SSP and CHORUS Data
Ono, Yoshiaki; Ouchi, Masami; Momose, Rieko +14 more
We conduct intensity mapping to probe for extended diffuse Lyα emission around Lyα emitters (LAEs) at z ~2-7, exploiting very deep (~26 mag at 5σ) and large-area (~4.5 deg2) Subaru/Hyper Suprime-Cam narrowband (NB) images and large LAE catalogs consisting of a total of 1540 LAEs at z = 2.2, 3.3, 5.7, and 6.6 obtained by the HSC-SSP and …
The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER). IV. Star Cluster Catalog
Bell, Eric F.; Williams, Benjamin F.; Johnson, L. Clifton +10 more
We construct a catalog of star clusters from Hubble Space Telescope images of the inner disk of the Triangulum Galaxy (M33) using image classifications collected by the Local Group Cluster Search, a citizen science project hosted on the Zooniverse platform. We identify 1214 star clusters within the Hubble Space Telescope imaging footprint of the P…
Variability Timescales of Hα on Active Mid-to-late M dwarfs
Winters, Jennifer G.; Medina, Amber A.; Charbonneau, David +2 more
We present a study of the variation timescales of the chromospheric activity indicator Hα on a sample of 13 fully convective, active mid-to-late M stars with masses between 0.1 and 0.3 solar masses. Our goal was to determine the dominant variability timescale and, by inference, a possible mechanism responsible for the variation. We gathered 10 or …