Search Publications
Spinning Bar and a Star-formation Inefficient Repertoire: Turbulence in Hickson Compact Group NGC 7674
Kewley, Lisa J.; Federrath, Christoph; Groves, Brent +2 more
The physics regulating star formation (SF) in Hickson Compact Groups (HCG) has thus far been difficult to describe, due to their unique kinematic properties. In this study, we expand upon previous works to devise a more physically meaningful SF relation able to better encompass the physics of these unique systems. We combine CO(1-0) data from the …
Heliospheric Maps from Cassini INCA Early in the Cruise to Saturn
Mitchell, D. G.; Krimigis, S.; Clark, G. +8 more
We present new energetic neutral atom (ENA) maps from the Ion and Neutral Camera (INCA) instrument on Cassini from the year 2000, prior to Cassini's encounter with Jupiter. These maps are the first produced for the year 2000 and are the only maps with comprehensive spatial coverage from the peak of solar cycle 23. These ENA maps span the energy ra…
Dying of the Light: An X-Ray Fading Cold Quasar at z ∼ 0.405
Kirkpatrick, Allison; Trump, Jonathan R.; LaMassa, Stephanie +11 more
Cold quasars are a rare subpopulation observed to host unobscured, X-ray luminous active galactic nuclei (AGN) while also retaining a cold gas supply fueling high star formation rates. These objects are interpreted as AGN early in their evolution. We present new SOFIA HAWC+ far-infrared observations, far-ultraviolet to far-infrared (FUV-FIR) photo…
On the Reliability of Photometric and Spectroscopic Tracers of Halo Relaxation
Gozaliasl, Ghassem; Zhoolideh Haghighi, Mohammad H.; Raouf, Mojtaba +2 more
We characterize the relaxation state of galaxy systems by providing an assessment of the reliability of the photometric and spectroscopic probe via the semianalytic galaxy evolution model. We quantify the correlations between the dynamical age of simuglated galaxy groups and popular proxies of halo relaxation in observation, which are mainly eithe…
OGLE-GAL-ACEP-091: The First Known Multi-mode Anomalous Cepheid
Soszyński, I.; Smolec, R.; Udalski, A. +12 more
Anomalous Cepheids (ACs) are metal-deficient, core-helium-burning pulsating stars with masses in the range 1.2-2.2 ${M}_{\odot }$ . Until recently, all known ACs were pure single-mode pulsators. The first candidate for an AC pulsating in more than one radial mode—OGLE-GAL-ACEP-091—was recently identified in the Milky Way based on the photometric d…
Revealing the Spectroscopic Variations of FU Orionis Object V960 Mon with High-resolution Spectroscopy
Honda, Satoshi; Itoh, Yoichi; Takagi, Yuhei +3 more
We present the results of the high-resolution spectroscopy of the FU Orionis-type star V960 Mon. The brightness of V960 Mon decreased continuously after the outburst was detected in 2014 November. During this dimming event, we carried out medium-resolution spectroscopic monitoring observations and found that the equivalent width of the absorption …
A New Microquasar Candidate in M83
Soria, Roberto; Blair, William P.; Long, Knox S. +2 more
Microquasars are neutron star or black hole X-ray binaries with jets. These jets can create bubbles of hot plasma shock ionized that can masquerade as peculiar supernova remnants (SNRs) in extragalactic surveys. To see if this is the case in the well-studied spiral galaxy M83, where one microquasar candidate (M83-MQ1) has already been identified, …
Type IIP Supernova Progenitors. II. Stellar Mass and Obscuration by the Dust in the Circumstellar Medium
Ray, Alak; Wagle, Gururaj A.
It has been well established from a variety of observations that red supergiants (RSGs) lose a lot of mass in stellar wind. Dust that has formed in this emitted gas over a few decades before core-collapse can lead to substantial extinction and obscure the intrinsic luminosity of the progenitor RSG. This may lead to a difficulty in determining the …
Young Stars near Cometary Globule CG 30 in the Tumultuous Gum Nebula
White, Russel J.; Yep, Alexandra C.
We have conducted a high-dispersion (R ∼ 34,000) optical spectroscopic study of 10 young stars near the cometary globule CG 30 in the Gum Nebula, a diffuse H II region home to at least 32 cometary globules. All 10 spectroscopically observed stars at the nebula's northern edge are of low mass (spectral types M4.5-K5), have broad Hα emission, and sh…
Spectroscopic Observations of High-speed Downflows in a C1.7 Solar Flare
Ding, M. D.; Li, Y.; Hong, Jie +2 more
In this paper, we analyze the high-resolution UV spectra for a C1.7 solar flare (SOL2017-09-09T06:51) observed by the Interface Region Imaging Spectrograph (IRIS). We focus on the spectroscopic observations at the locations where the cool lines of Si IV 1402.8 Å (∼104.8 K) and C II 1334.5/1335.7 Å (∼104.4 K) reveal significan…