Search Publications
Clusters, Clumps, Dust, and Gas (CCDG) in NGC 1614: Benchmarking Cluster Demographics in Extreme Systems
Whitmore, Bradley C.; Chandar, Rupali; Goudfrooij, Paul +3 more
Observations of young star clusters in a variety of galaxies have been used to constrain basic properties related to star formation, such as the fraction of stars found in clusters (Γ) and the shape of the cluster mass function (CMF). However, the results can depend heavily on the reliability of the cluster age-dating process and other assumptions…
Helioseismic Constraints: Past, Current, and Future Observations
Appourchaux, Thierry
I will review the history of the helioseismic observations since the beginning of the field. I will explain how each instrument was designed based upon the required observables, and to which modes these instruments are sensitive. The impact of these sensitivities on the rotation and structure inversion will be developed. I will conclude with what …
Spectroscopic survey of faint planetary-nebula nuclei: VI. Seventeen hydrogen-rich central stars
Bond, Howard E.; Zeimann, Gregory R.; Werner, Klaus +1 more
We present an analysis of 17 H-rich central stars of planetary nebulae (PNe) observed in our spectroscopic survey of nuclei of faint Galactic PNe carried out at the 10-m Hobby-Eberly Telescope. Our sample includes ten O(H) stars, four DAO white dwarfs (WDs), two DA WDs, and one sdOB star. The spectra were analyzed by means of NLTE model atmosphere…
Localization of the Gamma-Ray Emission Region in the 1 September 2014 Behind-the-Limb Solar Flare According to the Fermi/LAT Data
Grechnev, V. V.; Kochanov, A. A.; Kiselev, V. I. +1 more
Since the launch of the Fermi mission in 2008, it has become possible to study high-energy solar γ-rays with an unprecedented imaging capability. In particular, the position of the >100 MeVγ-ray source can shed light on the origin of high-energy protons that is still controversial. However, the imaging of solar γ-ray sources with the Fermi Larg…
The Interaction Jigsaw: investigating star formation in interacting galaxies
Mathew, Blesson; Kartha, Sreeja S.; Shridharan, B. +5 more
Interaction between galaxies plays a pivotal role in their evolution. Ongoing star formation in spiral galaxies can be affected by these processes. Interacting galaxy pairs provide an opportunity to study these effects. We select a sample of interacting galaxies in field environments at various interaction stages and are nearly face-on and chose g…
Full Abundance Study of Two Newly Discovered Barium Giants
Jofré, Paula; Vitali, Sara; Escorza, Ana +1 more
Barium (Ba) stars are chemically peculiar stars that show enhanced surface abundances of heavy elements produced by the slow-neutron-capture process, the so-called s-process. These stars are not sufficiently evolved to undergo the s-process in their interiors, so they are considered products of binary interactions. Ba stars form when a former Asym…
Cyclical Variations of Meridional Flows on the Sun
Bilenko, Irina A.
Based on a large volume of observational data of magnetic fields obtained at both ground-based and space observatories, cyclical variations of the meridional flows of the solar magnetic fields in 21–25 cycles of solar activity are considered. It is shown that magnetic fields of medium strength of different polarities form oppositely directed magne…
CZ Aqr: An Oscillating Eclipsing Algol-type System Composed of a δ Sct Primary Star and a Subgiant Star in a Quadruple System
Li, Lin-Jia; Qian, Sheng-Bang; Liao, Wen-Ping +3 more
Eclipsing Algol-type systems containing a δ Scuti (hereafter δ Sct) star enable precise determination of physical parameters and the investigation of stellar internal structure and evolution. We present the absolute parameters of CZ Aquarius (hereafter CZ Aqr) based on TESS data. CZ Aqr has an orbital period of 0.86275209 day, a mass ratio of 0.48…
Multi-instrument observations and tracking of a coronal mass ejection front from low to middle corona
Stepanyuk, Oleg; Kozarev, Kamen
The shape and dynamics of coronal mass ejections (CMEs) vary significantly based on the instrument and wavelength used. This has led to significant debate about the proper definitions of CME/shock fronts, pile-up/compression regions, and core observations in projection in optically thin vs. optically thick emission. Here we present an observationa…
The spatially resolved relation between dust, gas, and metal abundance with the TYPHOON survey
Kewley, Lisa J.; Madore, Barry F.; Beaton, Rachael L. +12 more
We present the spatially resolved relationship between the dust-to-gas mass ratio (DGR) and gas-phase metallicity (