Search Publications
SAUNAS. II. Discovery of Cross-shaped X-Ray Emission and a Rotating Circumnuclear Disk in the Supermassive S0 Galaxy NGC 5084
Koekemoer, Anton M.; Laine, Seppo; Lopez-Rodriguez, Enrique +11 more
Combining Chandra, Atacama Large Millimeter/submillimeter Array, EVLA, and Hubble Space Telescope archival data and newly acquired data from the Apache Point Observatory/Dual Imaging Spectrograph, we detect a double-lobed 17 kpc X-ray emission with plumes oriented approximately perpendicular and parallel to the galactic plane of the massive lentic…
Cold Water Emission Cannot Be Used to Infer Depletion of Bulk Elemental Oxygen [O/H] in Disks
Gorti, Uma; Ruaud, Maxime
We reexamine the constraints provided by Herschel Space Observatory data regarding cold water emission from protoplanetary disks. Previous disk models that were used to interpret observed water emission concluded that oxygen (O/H) is depleted by at least 2 orders of magnitude if a standard, interstellar gas/dust mass ratio is assumed in the disk. …
Investigating the Mass of the Black Hole and Possible Wind Outflow of the Accretion Disk in the Tidal Disruption Event AT2021ehb
Drake, Jeremy J.; Zoghbi, Abderahmen; Miller, Jon M. +11 more
Tidal disruption events (TDEs) can potentially probe low-mass black holes (BHs) in host galaxies that might not adhere to bulge or stellar-dispersion relationships. At least initially, TDEs can also reveal super-Eddington accretion. X-ray spectroscopy can potentially constrain BH masses, and reveal ionized outflows associated with super-Eddington …
Persistent Homology Analysis for Solar Magnetograms
Toriumi, Shin; Katsukawa, Yukio; Orozco Suárez, D. +1 more
Understanding the magnetic fields of the Sun is essential for unraveling the underlying mechanisms driving solar activity. Integrating topological data analysis techniques into these investigations can provide valuable insights into the intricate structures of magnetic fields, enhancing our comprehension of solar activity and its implications. In …
On the 3D Transport of Low-energy Galactic Cosmic-ray and Jovian Electrons in the Inner Heliosphere in the Presence of a Fisk-type Heliospheric Magnetic Field
Engelbrecht, N. E.
Modeling the transport of low-energy (1‑10 MeV) cosmic-ray electrons can lead to valuable insights as to the behavior of the heliospheric magnetic field (HMF), due to the fact that the mean free path (MFP) of these particles parallel to the HMF is significantly larger than their perpendicular MFP, and that these particles experience little in the …
NNHMC: An Efficient Stokes Inversion Method Using a Neural Network (NN) Model Combined with the Hamiltonian Monte Carlo (HMC) Algorithm
Ji, KaiFan; Wang, JinLiang; Liu, Hui +6 more
The Milne–Eddington (M-E) atmosphere model is commonly adopted in the inversion of the magnetic fields in the solar photosphere. By applying the Levenberg–Marquardt algorithm or training a neural network (NN) model, the magnetic field vector can be quickly inferred from the Stokes profile but lacks reliable and statistically well-defined confidenc…
COBIPULSE: A Systematic Search for Compact Binary Millisecond Pulsars
Miles-Páez, Paulo A.; Turchetta, Marco; Simpson, Jordan A. +5 more
We report here the results obtained from a systematic optical photometric survey aimed at finding new compact binary millisecond pulsars (also known as "spiders"): the COmpact BInary PULsar SEarch. We acquired multiband optical images over 1 yr around 33 unidentified Fermi Large Area Telescope sources, selected as pulsar candidates based on their …
Enhanced Oxygen Ion Outflow at Earth and Mars due to the Concurrent Impact of a Stream Interaction Region
Thampi, Smitha V.; Bhaskar, Ankush; Venkataraman, V. +1 more
One of the major processes that solar wind drives is the outflow and escape of ions from the planetary atmospheres. The major ion species in the upper ionospheres of both Earth and Mars is O+, and hence it is more likely to dominate the escape process. On Earth, due to a strong intrinsic magnetic field, the major ion outflow pathways ar…
Meridional Flow in the Solar Polar Caps Revealed by Magnetic Field Observation and Simulation
Hou, Yijun; Li, Ting; Yang, Shuhong +10 more
As a large-scale motion on the Sun, the meridional flow plays an important role in determining magnetic structure and strength and solar cycle. However, the meridional flow near the solar poles is still unclear. The Hinode observations show that the magnetic flux density in polar caps decreases from the lower latitudes to the poles. Using a surfac…
An Analysis of the Complex and Compact Outflow Cavity Carved by HOPS 361-A in NGC 2071 IR
Narang, Mayank; Coudé, Simon; Quillen, Alice C. +10 more
We present a combined Stratospheric Observatory for Infrared Astronomy (SOFIA) and two-epoch Hubble Space Telescope (HST) study of the region NGC 2071 IR containing the outflow from the protostar HOPS 361-A (NGC 2071 IRS 1). New [O I] 63 µm spectra, taken with the German REciever for Astronomy at Terahertz frequencies (GREAT) instrument aboa…