Search Publications
The Effect of Environment on Star Formation Activity and Morphology at 0.5 < z < 2.5 in CANDELS
Fang, Guanwen; Gu, Yizhou; Yuan, Qirong +2 more
To explore the effect of environment on star formation and the morphological transformation of high-redshift galaxies, we present a robust estimation of localized galaxy overdensity using a density estimator within the Bayesian probability framework. The maps of environmental overdensity at 0.5 < z < 2.5 are constructed for the five CANDELS …
Core Mass Function of a Single Giant Molecular Cloud Complex with 10,000 Cores
Qiu, Keping; Cao, Yue; Zhang, Qizhou +2 more
Similarity in shape between the initial mass function (IMF) and the core mass functions (CMFs) in star-forming regions prompts the idea that the IMF originates from the CMF through a self-similar core-to-star mass mapping process. To accurately determine the shape of the CMF, we create a sample of 8431 cores with the dust continuum maps of the Cyg…
Bursts before Burst: A Comparative Study on FRB 200428-associated and FRB-absent X-Ray Bursts from SGR J1935+2154
Lin, Lin; Zhang, Bing; Dai, Zi-Gao +8 more
Accompanied by an X-ray burst, the fast radio burst (FRB) FRB 200428 was recently confirmed as originating from the Galactic magnetar soft gamma repeater (SGR) SGR J1935+2154. Just before and after FRB 200428 was detected, the Five-hundred-meter Aperture Spherical radio Telescope (FAST) had been monitoring SGR J1935+2154 for eight hours. From UTC …
The Masses of Supernova Remnant Progenitors in NGC 6946
Williams, Benjamin F.; Blair, William P.; Dolphin, Andrew +5 more
We constrained the progenitor masses for 169 supernova remnants (SNRs), eight historically observed supernovae (SNe), and the black hole formation candidate in NGC 6946, finding that they are consistent with originating from a standard initial mass function. Additionally, there were 16 remnants that showed no sign of nearby star formation consiste…
Probing the Hot Circumgalactic Medium with Broad O VI and X-Rays
Nicastro, Fabrizio; Mathur, Smita; Gupta, Anjali +2 more
Most of the baryonic mass in the circumgalactic medium (CGM) of a spiral galaxy is believed to be warm-hot, with temperature around 106 K. The narrow O VI absorption lines probe a somewhat cooler component at $\mathrm{log}\,T({\rm{K}})=5.5$ , but broad O VI absorbers have the potential to probe the hotter CGM. Here we present 376 ks Cha…
Discovery of a Protocluster Core Associated with an Enormous Lya Nebula at z = 2.3
Fan, Xiaohui; Cai, Zheng; Li, Qiong +10 more
The MAMMOTH-1 nebula at z = 2.317 is an enormous Lyα nebula (ELAN) extending to a ~440 kpc scale at the center of the extreme galaxy overdensity BOSS 1441. In this paper, we present observations of the CO(3 - 2) and 250 GHz dust-continuum emission from MAMMOTH-1 using the IRAM NOrthern Extended Millimeter Array. Our observations show that CO(3 - 2…
A Spatially Resolved Survey of Distant Quasar Host Galaxies. II. Photoionization and Kinematics of the ISM
Armus, Lee; Larkin, James E.; Wright, Shelley A. +6 more
We present detailed observations of photoionization conditions and galaxy kinematics in 11 z = 1.39-2.59 radio-loud quasar host galaxies. Data were taken with the OSIRIS integral field spectrograph and the adaptive optics system at the W. M. Keck Observatory that targeted nebular emission lines (Hβ, [O III], Hα, [N II]) redshifted into the near-in…
Years-delayed X-Ray Afterglows of TDEs Originated from Wind-Torus Interactions
Wang, Wei; Shu, Xinwen; Jiang, Ning +8 more
Tidal disruption events (TDEs) occurring in active galactic nuclei (AGNs) are a special class of sources with outstanding scientific significance. TDEs can generate ultrafast winds, which should almost inevitably collide with the preexisting AGN dusty tori. We perform analytical calculations and simulations on the wind-torus interactions and find …
New Families in our Solar Neighborhood: Applying Gaussian Mixture Models for Objective Classification of Structures in the Milky Way and in Simulations
Faucher-Giguère, Claude-André; Sharma, Sanjib; Bonaca, Ana +10 more
The standard picture of galaxy formation motivates the decomposition of the Milky Way into 3-4 stellar populations with distinct kinematic and elemental abundance distributions: the thin disk, thick disk, bulge, and stellar halo. To test this idea, we construct a Gaussian mixture model (GMM) for both simulated and observed stars in the solar neigh…
The Source Locations of Major Flares and CMEs in Emerging Active Regions
Wang, Yuming; Liu, Lijuan; Cui, Jun +1 more
Major flares and coronal mass ejections (CMEs) tend to originate from compact polarity inversion lines (PILs) in solar active regions (ARs). Recently, a scenario named "collisional shearing" was proposed by Chintzoglou et al. to explain the phenomenon, which suggests that the collision between different emerging bipoles is able to form a compact P…