Search Publications
Low-frequency Radio Continuum Imaging and SED Modeling of 11 LIRGs: Radio-only and FUV to Radio Bands
Małek, Katarzyna; Charmandaris, Vassilis; Seymour, Nicholas +5 more
We present a detailed analysis of 11 local luminous infrared galaxies from ultraviolet through far-infrared to radio (~70 MHz to ~15 GHz) bands. We derive the astrophysical properties through spectral energy distribution (SED) modeling using the Code Investigating GALaxy Emission (CIGALE) and UltraNest codes. The radio SEDs include our new observa…
Diagnosing the Optically Thick/Thin Features Using the Intensity Ratio of Si IV Resonance Lines in Solar Flares
Ding, M. D.; Li, Y.; Hong, Jie +1 more
In the optically thin regime, the intensity ratio of the two Si IV resonance lines (1394 and 1403 Å) are theoretically the same as the ratio of their oscillator strengths, which is exactly 2. Here, we study the ratio of the integrated intensity of the Si IV lines (R = ∫I 1394(λ)dλ/∫I 1403(λ)dλ) and the ratio of intensity at e…
The Accretion Process in the DQ Tau Binary System
Ábrahám, P.; Kóspál, Á.; Fiorellino, E. +1 more
Mass accretion from the circumstellar disk onto the protostar is a fundamental process during star formation. Measuring the mass accretion rate is particularly challenging for stars belonging to binary systems, because it is often difficult to discriminate which component is accreting. DQ Tau is an almost equal-mass spectroscopic binary system whe…
Binaries with Possible Compact Components Discovered from the LAMOST Time-domain Survey of Four K2 Plates
Liu, Jifeng; Zhang, Haotong; Wang, Song +4 more
Time-domain spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) can provide accurate and high-cadence radial velocities (RVs). In this work, we search for binaries with compact components with the RV monitoring method by using the LAMOST time-domain survey of four K2 plates. Three binary systems including…
Independent Evidence for Earlier Formation Epochs of Fossil Groups of Galaxies through the Intracluster Light: The Case for RX J100742.53+380046.6
Koekemoer, Anton M.; Dupke, Renato A.; Carrasco, Eleazar R. +9 more
Fossil groups (FG) of galaxies still present a puzzle to theories of structure formation. Despite the low number of bright galaxies, they have relatively high velocity dispersions and ICM temperatures often corresponding to cluster-like potential wells. Their measured concentrations are typically high, indicating early formation epochs as expected…
Multiwavelength Vertical Structure in the AU Mic Debris Disk: Characterizing the Collisional Cascade
MacGregor, Meredith A.; Hughes, A. Meredith; Wilner, David J. +9 more
Debris disks are scaled-up analogs of the Kuiper Belt in which dust is generated by collisions between planetesimals. In the collisional cascade model of debris disks, the dust lost to radiation pressure and winds is constantly replenished by grinding collisions between planetesimals. The model assumes that collisions are destructive and involve l…
Follow-up Observations of the Prolonged, Super-Eddington, Tidal Disruption Event Candidate 3XMM J150052.0+015452: the Slow Decline Continues
Ramirez-Ruiz, Enrico; Komossa, S.; Maksym, W. Peter +7 more
The X-ray source 3XMM J150052.0+015452 was discovered as a spectacular tidal disruption event candidate during a prolonged (>11 yr) outburst. It exhibited unique quasi-soft X-ray spectra of characteristic temperature kT ~ 0.3 keV for several years at the peak, but in a recent Chandra observation (10 yr into the outburst) a super-soft X-ray spec…
Testing Velocity Kinks as a Planet Detection Method: Do Velocity Kinks in Surface Gas Emission Trace Planetary Spiral Wakes in the Midplane Continuum?
Dong, Ruobing; Speedie, Jessica
Spiral density waves generated by an embedded planet are understood to cause "kinks" in observed velocity channel maps of CO surface emission by perturbing the gas motion within the spiral arms. If velocity kinks are a reliable probe of embedded planets, we should expect to see the planet-driven spiral arms in other observational tracers. We test …
ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): Evidence for a Molecular Jet Launched at an Unprecedented Early Phase of Protostellar Evolution
Sanhueza, Patricio; Kwon, Woojin; Soam, Archana +31 more
Protostellar outflows and jets play a vital role in star formation as they carry away excess angular momentum from the inner disk surface, allowing the material to be transferred toward the central protostar. Theoretically, low-velocity and poorly collimated outflows appear from the beginning of the collapse at the first hydrostatic core (FHSC) st…
A Segmented Period-Luminosity Relation for Nearby Extragalactic Delta Scuti Stars
Martínez-Vázquez, C. E.; Catelan, M.; Vivas, A. K. +1 more
The period-luminosity relations (PLRs) of Milky Way δ Scuti (δ Sct) stars have been described to the present day by a linear relation. However, when studying extragalactic systems such as the Magellanic Clouds and several dwarf galaxies, we notice for the first time a nonlinear behavior in the PLR of δ Sct stars. Using the largest sample of ~3700 …