Search Publications
Planetary Nebula Morphologies Indicate a Jet-Driven Explosion of SN 1987A and Other Core-Collapse Supernovae
Soker, Noam
I demonstrate the usage of planetary nebulae (PNe) to infer that a pair of jets shaped the ejecta of the core-collapse supernova (CCSN) SN 1987A. The main structure of the SN 1987A inner ejecta, the 'keyhole', comprises two low-intensity zones. The northern one has a bright rim on its front, while the southern one has an elongated nozzle. An earli…
A Dust-Scattering Model for M1-92: A Revised Estimate of the Mass Distribution and Inclination
Morris, Mark R.; Sahai, Raghvendra; Li, Yun Qi
Preplanetary nebulae (PPNe) are formed from mass-ejecting late-stage AGB stars. Much of the light from the star gets scattered or absorbed by dust particles, giving rise to the observed reflection nebula seen at visible and near-IR wavelengths. Precursors to planetary nebulae (PNe), PPNe generally have not yet undergone any ionization by UV radiat…
Steps toward Unraveling the Structure and Formation of Five Polar Ring Galaxies
Kulkarni, Varsha P.; Aller, Monique C.; Lackey, Kyle E.
Polar ring galaxies (PRGs) are unusual relative to common galaxies in that they consist of a central host galaxy—usually a gas-poor, early-type S0 or elliptical galaxy—surrounded by a ring of gas, dust and stars that orbit perpendicular to the major axis of the host. Despite the general quiescence of early-type galaxies (ETGs) and the rings' lack …
Insight on AGB Mass-Loss and Dust Production from PNe
Tosi, Silvia
The asymptotic giant branch (AGB) phase, experienced by low- and intermediate-mass stars (LIMSs), plays a crucial role in galaxies due to its significant dust production. Planetary nebulae (PNe) offer a novel perspective, providing valuable insights into the dust production mechanisms and the evolutionary history of LIMSs. We selected a sample of …
Young Radio Sources Expanding in Gas-Rich ISM: Using Cold Molecular Gas to Trace Their Impact
Morganti, Raffaella; Oosterloo, Tom; Murthy, Suma +2 more
We present an overview of the results obtained from the study of the resolved distribution of molecular gas around eight young (≲106yr), peaked-spectrum radio galaxies. Tracing the distribution and kinematics of the gas around these radio sources allows us to trace the interplay between the jets and the surrounding medium. For three of these sourc…
Metal Content in Relativistically Jetted and Radio-Quiet Quasars in the Main Sequence Context
Panda, Swayamtrupta; Marziani, Paola; Deconto Machado, Alice +1 more
The optical and UV properties of radio-quiet (RQ) and radio-loud (RL, relativistically "jetted") active galactic nuclei (AGN) are known to differ markedly; however, it is still unclear what is due to a sample selection and what is associated with intrinsic differences in the inner workings of their emitting regions. Chemical composition is an impo…
Spirality: A Novel Way to Measure Spiral Arm Pitch Angle
Davis, Benjamin L.; Boe, Benjamin; Kennefick, Daniel +7 more
We present the MATLAB code Spirality, a novel method for measuring spiral arm pitch angles by fitting galaxy images to spiral templates of known pitch. Computation time is typically on the order of 2 min per galaxy, assuming 8 GB of working memory. We tested the code using 117 synthetic spiral images with known pitches, varying both the spiral pro…
Cosmological Model Tests with JWST
Lovyagin, Nikita; Raikov, Alexander; Yershov, Vladimir +1 more
The James Webb Space Telescope (JWST), which has recently become operational, is capable of detecting objects at record-breaking redshifts, z≳15. This is a crucial advance for observational cosmology, as at these redshifts the differences between alternative cosmological models manifest themselves in the most obvious way. In recent years, some obs…
The Accreting White Dwarfs in Cataclysmic Variables
Sion, Edward M.; Godon, Patrick
Accreting white dwarfs (WDs) in cataclysmic variables (CVs) provide crucial insights about the accretion of mass and angular momentum in all types of binaries, including accreting NSs and BHs. Accreting WDs are the critical component in the single degenerate pathway to SNe Ia, along with the double degenerate merger pathway, they are the standard …
Plasma Diagnostics in the Era of Integral Field Spectroscopy
Ueta, Toshiya
To understand the physical conditions of various gaseous systems, plasma diagnostics must be performed properly. To that end, it is equally important to have extinction correction performed properly, even before performing plasma diagnostics. This means that the physical conditions of the target sources—the very quantities to be derived via plasma…