Search Publications
Distinguishing Dark Matter Cusps from Cores Using Globular Clusters
Greene, Jenny E.; Danieli, Shany; Modak, Shaunak
Globular clusters (GCs) provide valuable insight into the properties of their host galaxies' dark matter halos. Using N-body simulations incorporating semianalytic dynamical friction and GC-GC merger prescriptions, we study the evolution of GC radial distributions and mass functions in cuspy and cored dark matter halos. Modeling the dynamics of th…
Energetics of a Solar Flare and a Coronal Mass Ejection Generated by a Hot Channel Eruption
Li, Dong; Zhang, Qingmin; Zhang, Yanjie +2 more
Hot channels (HCs) are prevalent in the solar corona and play a critical role in driving flares and coronal mass ejections (CMEs). In this paper, we estimate the energy content of an X1.4 eruptive flare with a fast CME generated by an HC eruption on 2011 September 22. Originating from NOAA Active Region 11302, the HC is the most dramatic feature i…
Isotopic Enrichment of Planetary Systems from Asymptotic Giant Branch Stars
Parker, Richard J.; Schoettler, Christina
Short-lived radioisotopes, in particular 26Al and 60Fe, are thought to contribute to the internal heating of the Earth, but are significantly more abundant in the solar system compared to the interstellar medium. The presence of their decay products in the oldest solar system objects argues for their inclusion in the Sun's pr…
Investigating the Dominant Environmental Quenching Process in UVCANDELS/COSMOS Groups
Finkelstein, Steven L.; Arrabal Haro, Pablo; Dickinson, Mark +36 more
We explore how the fraction of quenched galaxies changes in groups of galaxies with respect to the distance to the center of the group, redshift, and stellar mass to determine the dominant process of environmental quenching in 0.2 < z < 0.8 groups. We use new UV data from the UVCANDELS project in addition to existing multiband photometry to …
The Direct-method Oxygen Abundance of Typical Dwarf Galaxies at Cosmic High Noon
Richard, Johan; Siana, Brian; Freeman, William R. +5 more
We present a Keck/MOSFIRE rest-optical composite spectrum of 16 typical gravitationally lensed star-forming dwarf galaxies at 1.7 ≲ z ≲ 2.6 (z mean = 2.30), all chosen independent of emission-line strength. These galaxies have a median stellar mass of $\mathrm{log}{({M}_{* }/{M}_{\odot })}_{\mathrm{med}}={8.29}_{-0.43}^{+0.51}$ and a me…
Varstrometry for Off-nucleus and Dual Sub-kiloparsec Active Galactic Nuclei (VODKA): Very Long Baseline Array Searches for Dual or Off-nucleus Quasars and Small-scale Jets
Shen, Yue; Zakamska, Nadia L.; Lazio, Joseph +5 more
Dual and off-nucleus active supermassive black holes are expected to be common in the hierarchical structure formation paradigm, but their identification at parsec scales remains a challenge due to strict angular resolution requirements. We conducted a systematic study using the Very Long Baseline Array (VLBA) to examine 23 radio-bright candidate …
Evolution of the Radial Size and Expansion of Coronal Mass Ejections Investigated by Combining Remote and In Situ Observations
Lugaz, Noé; Zhuang, Bin; Scolini, Camilla +4 more
A fundamental property of coronal mass ejections (CMEs) is their radial expansion, which determines the increase in the CME radial size and the decrease in the CME magnetic field strength as the CME propagates. CME radial expansion can be investigated either by using remote observations or by in situ measurements based on multiple spacecraft in ra…
Accelerated Structural Evolution of Galaxies in a Starbursting Cluster at z = 2.51
Daddi, Emanuele; Lu, Shiying; Elbaz, David +11 more
Structural properties of cluster galaxies during their peak formation epoch, z ~ 2-4 provide key information on whether and how the environment affects galaxy formation and evolution. Based on deep Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) imaging toward the z = 2.51 cluster, J1001, we explore environmental effects on the structure, …
Strongest Coronal Magnetic Fields in Solar Cycles 23 and 24: Probing, Statistics, and Implications
Fleishman, Gregory D.; Anfinogentov, Sergey A.; Fedenev, Viktor V.
A strong coronal magnetic field, when present, manifests itself as bright microwave sources at high frequencies produced by the gyroresonant (GR) emission mechanism in thermal coronal plasma. The highest frequency at which this emission is observed is proportional to the absolute value of the strongest coronal magnetic field on the line of sight. …
X-Ray Studies of the Pulsar PSR J1420-6048 and Its TeV Pulsar Wind Nebula in the Kookaburra Region
Woo, Jooyun; An, Hongjun; Mori, Kaya +4 more
We present a detailed analysis of broadband X-ray observations of the pulsar PSR J1420-6048 and its wind nebula (PWN) in the Kookaburra region with Chandra, XMM-Newton, and NuSTAR. Using the archival XMM-Newton and new NuSTAR data, we detected 68 ms pulsations of the pulsar and characterized its X-ray pulse profile, which exhibits a sharp spike an…