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1. Near-infrared and Optical Observations of Type Ic SN 2020oi and Broad-lined Type Ic SN 2020bvc: Carbon Monoxide, Dust, and High-velocity Supernova Ejecta

   https://doi.org/10.3847/1538-4357/abd850  

   Rho, J. ; Evans, A. ; Geballe, T. R. ; Banerjee, D. P. ; Hoeflich, P. ; Shahbandeh, M. ; Valenti, S. ; Yoon, S.-C. ; Jin, H. ; Williamson, M. ; et al ( February 2021 , The Astrophysical Journal)

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2. The 3D geometry of reflection nebulae IC 59 and IC 63 with their illuminating star gamma Cas

   https://doi.org/10.1093/mnras/stae102  

   Eiermann, Jacob M. ; Caputo, Miranda ; Lai, Thomas S. -Y ; Witt, Adolf N. ( January 2024 , Monthly Notices of the Royal Astronomical Society)

   The early-type star gamma Cas illuminates the reflection nebulae IC 59 and IC 63, creating two photodissociation regions (PDRs). Uncertainties about the distances to the nebulae and the resulting uncertainty about the density of the radiation fields incident on their surfaces have hampered the study of these PDRs during the past three decades. We employed far-ultraviolet (UV) – optical nebula – star colour differences of dust-scattered light to infer the locations of the nebulae relative to the plane of the sky containing gamma Cas, finding IC 63 to be positioned behind the star and IC 59 in front of the star. To obtain the linear distances of the nebulae relative to gamma Cas, we fit far-infrared archival Herschel flux data for IC 59 and IC 63 with modified blackbody curves and relate the resulting dust temperatures with the luminosity of gamma Cas, yielding approximate distances of 4.15 pc for IC 59 and 2.3 pc for IC 63. With these distances, using updated far-UV flux data in the 6–13.6 eV range for gamma Cas with two recent determinations of the interstellar extinction for gamma Cas, we estimate that the far-UV radiation density at the surface of IC 63 takes on values of G0 = 58 or G0 = 38 with respective values for E(B − V) for gamma Cas of 0.08 and 0.04 mag. This is a substantial reduction from the range 150 ≤ G0 ≤ 650 used for IC 63 during the past three decades. The corresponding, even lower new values for IC 59 are G0 = 18 and G0 = 12.

    

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3. Physics and Chemistry of Radiation Driven Cloud Evolution. [C ii] Kinematics of IC 59, and IC 63

   https://doi.org/10.3847/1538-4357/acd2d5  

   Caputo, Miranda ; Soam, Archana ; Andersson, B-G ; Dennis, Remy ; Chambers, Ed ; Güsten, Rolf ; Knee, Lewis B. G. ; Stutzki, Jürgen ( June 2023 , The Astrophysical Journal)

   We used high-resolution [Cii] 158μm mapping of two nebulae IC 59 and IC 63 from SOFIA/upGREAT in conjunction with ancillary data of the gas, dust, and polarization to probe the kinematics, structure, and magnetic properties of their photodissociation regions (PDRs). The nebulae are part of the Sh 2-185 Hiiregion that is illuminated by the B0 IVe starγCas. The velocity structure of each PDR changes with distance fromγCas, which is consistent with driving by the radiation. Based on previous far-ultraviolet (FUV) flux measurements of, and the known distance to,γCas, along with the predictions of 3D distances to the clouds, we estimated the FUV radiation field strength (G₀) at the clouds. Assuming negligible extinction between the star and clouds, we find their 3D distances fromγCas. For IC 63, our results are consistent with earlier estimates of distance from Andersson et al., locating the cloud at ∼2 pc fromγCas at an angle of 58° to the plane of the sky behind the star. For IC 59, we derive a distance of 4.5 pc at an angle of 70° in front of the star. We do not detect any significant correlation between the orientation of the magnetic field and the velocity gradients of [Cii] gas, which indicates a moderate magnetic field strength. The kinetic energy in IC 63 is estimated to be an order of 10 higher than the magnetic energies. This suggests that kinetic pressure in this nebula is dominant.

    

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4. Deciphering the Origin of Ionized Gas in IC 1459 with VLT/MUSE

   https://doi.org/10.1093/mnras/stab1137  

   Mulcahey, C R ; Prichard, L J ; Krajnović, D ; Jorgenson, R A ( April 2021 , Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   Abstract IC 1459 is an early-type galaxy (ETG) with a rapidly counter-rotating stellar core, and is the central galaxy in a gas-rich group of spirals. In this work, we investigate the abundant ionized gas in IC 1459 and present new stellar orbital models to connect its complex array of observed properties and build a more complete picture of its evolution. Using the Multi-Unit Spectroscopic Explorer (MUSE), the optical integral field unit (IFU) on the Very Large Telescope (VLT), we examine the gas and stellar properties of IC 1459 to decipher the origin and powering mechanism of the galaxy’s ionized gas. We detect ionized gas in a non-disk-like structure rotating in the opposite sense to the central stars. Using emission-line flux ratios and velocity dispersion from full-spectral fitting, we find two kinematically distinct regions of shocked emission-line gas in IC 1459, which we distinguished using narrow (σ ≤ 155 km s−1) and broad (σ > 155 km s−1) profiles. Our results imply that the emission-line gas in IC 1459 has a different origin than that of its counter-rotating stellar component. We propose that the ionized gas is from late-stage accretion of gas from the group environment, which occurred long after the formation of the central stellar component. We find that shock heating and AGN activity are both ionizing mechanisms in IC 1459 but that the dominant excitation mechanism is by post-asymptotic giant branch stars from its old stellar population. 

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5. Comparison of Drug Inhibitory Effects ($$\hbox {IC}_{50}$$) in Monolayer and Spheroid Cultures

   https://doi.org/10.1007/s11538-020-00746-7  

   Berrouet, Catherine ; Dorilas, Naika ; Rejniak, Katarzyna A. ; Tuncer, Necibe ( June 2020 , Bulletin of Mathematical Biology)

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