Search Publications
Outflows in the radio-intermediate quasar III Zw 2: a polarization study with the EVLA and uGMRT
Ho, L. C.; Ishwara-Chandra, C. H.; Harrison, C. M. +4 more
We present results from a polarization study of the radio-intermediate quasar, III Zw 2, at a redshift of 0.089, with the upgraded Giant Metrewave Radio Telescope (uGMRT) at 685 MHz and the Karl G. Jansky Very Large Array (VLA) at 5 and 34 GHz. We detect a kpc-scale outflow, exhibiting transverse magnetic (B-) fields. The curved jet terminates in …
Mass and density of the transiting hot and rocky super-Earth LHS 1478 b (TOI-1640 b)
Kuzuhara, M.; Tamura, M.; Kudo, T. +52 more
One of the main objectives of the Transiting Exoplanet Survey Satellite (TESS) mission is the discovery of small rocky planets around relatively bright nearby stars. Here, we report the discovery and characterization of the transiting super-Earth planet orbiting LHS 1478 (TOI-1640). The star is an inactive red dwarf (J ~ 9.6 mag and spectral type …
Head-to-Toe Measurement of El Gordo: Improved Analysis of the Galaxy Cluster ACT-CL J0102-4915 with New Wide-field Hubble Space Telescope Imaging Data
Sifón, Cristóbal; Hughes, John P.; Jee, M. James +6 more
We present an improved weak-lensing (WL) study of the high-z (z = 0.87) merging galaxy cluster ACT-CL J0102-4915 ("El Gordo") based on new wide-field Hubble Space Telescope imaging data. The new imaging data cover the ~3.5 × ~3.5 Mpc region centered on the cluster and enable us to detect WL signals beyond the virial radius, which was not possible …
Revisiting Dynamical Friction: The Role of Global Modes and Local Wakes
Babul, Arif; Quinn, Thomas R.; Mayer, Lucio +4 more
The orbital decay of a perturber within a larger system plays a key role in the dynamics of many astrophysical systems-from nuclear star clusters or globular clusters in galaxies, to massive black holes in galactic nuclei, to dwarf galaxy satellites within the dark matter halos of more massive galaxies. For many decades, there have been various at…
The Ultraviolet Extinction Map and Dust Properties at High Galactic Latitude
Jiang, Biwei; Yuan, Haibo; Li, Jun +1 more
Extinction in ultraviolet is much more significant than in optical or infrared, which can be very informative to precisely measure the extinction and understand the dust properties in the low-extinction areas. The high Galactic latitude sky is such an area, important for studying the extragalactic sky and the universe. Based on the stellar paramet…
The importance of lake breach floods for valley incision on early Mars
Goudge, Timothy A.; Fassett, Caleb I.; Morgan, Alexander M. +1 more
The surface environment of early Mars had an active hydrologic cycle, including flowing liquid water that carved river valleys1-3 and filled lake basins4-6. Over 200 of these lake basins filled with sufficient water to breach the confining topography4,6, causing catastrophic flooding and incision of outlet canyons<…
Variations of the Galactic Cosmic Rays in the Recent Solar Cycles
Zhao, Lingling; Fu, Shuai; Zhang, Xiaoping +1 more
In this paper, we study the Galactic cosmic-ray (GCR) variations over the solar cycles 23 and 24, with measurements from NASA's Advanced Composition Explorer/Cosmic Ray Isotope Spectrometer instrument and the ground-based neutron monitors (NMs). The results show that the maximum GCR intensities of heavy nuclei (5 ≤ Z ≤ 28, 50∼500 MeV nuc-1
Orbits of 152 globular clusters of the MilkyWay galaxy constructed from Gaia DR2
Bajkova, Anisa Talgatovna; Bobylev, Vadim Vadimovich
We present orbits and their properties for 152 globular clusters of the Milky Way galaxy obtained using average Gaia DR2 proper motions and other astrometric data from the list of Vasiliev. For orbital integration we have applied the axisymmetric model of the Galactic potential based on the Navarro-Frenk- White dark halo, and modified by Bajkova &…
The Milky Way's bar structural properties from gravitational waves
Korol, Valeriya; Rossi, Elena M.; D'Onghia, Elena +1 more
The Laser Interferometer Space Antenna (LISA) will enable Galactic gravitational wave (GW) astronomy by individually resolving >104 signals from double white dwarf (DWD) binaries throughout the Milky Way. Since GWs are unaffected by stellar crowding and dust extinction unlike optical observations of the Galactic plane, in this work, …
R-process-rich Stellar Streams in the Milky Way
Roederer, Ian U.; Frebel, Anna; Ji, Alexander P. +3 more
We present high-resolution Magellan/MIKE spectra of 22 bright (9 < V < 13.5) metal-poor stars (-3.18 < [Fe/H] < -1.37) in three different stellar streams, the Helmi debris stream, the Helmi trail stream, and the ω Centauri progenitor stream. We augment our Helmi debris sample with results for 10 stars by Roederer et al. for a total of …