Search Publications
Tomography of the Unique Ongoing Jet in the Planetary Nebula NGC 2392
Guerrero, M. A.; Toalá, J. A.; Ramos-Larios, G. +5 more
Jets (fast collimated outflows) are claimed to be the main shaping agent of the most asymmetric planetary nebulae (PNs), as they impinge on the circumstellar material at late stages of the asymptotic giant branch phase. The first jet detected in a PN was that of NGC 2392, yet there is no available image because of its low surface brightness contra…
On the Nature of AGN and Star Formation Enhancement in the z = 3.1 SSA22 Protocluster: The HST WFC3 IR View
Kubo, Mariko; Umehata, Hideki; Alexander, David M. +9 more
We examine possible environmental sources of the enhanced star formation and active galactic nucleus (AGN) activity in the z = 3.09 SSA22 protocluster using Hubble WFC3 F160W (~1.6 µm) observations of the SSA22 field, including new observations centered on eight X-ray selected protocluster AGN. To investigate the role of mergers in the obser…
Photoionized Herbig-Haro Objects in the Orion Nebula through Deep High Spectral Resolution Spectroscopy. II. HH 204
Henney, W. J.; Méndez-Delgado, J. E.; Arellano-Córdova, K. Z. +3 more
We analyze the physical conditions, chemical composition, and other properties of the photoionized Herbig-Haro (HH) object HH 204 through Very Large Telescope echelle spectroscopy and Hubble Space Telescope imaging. We kinematically isolate the high-velocity emission of HH 204 from the emission of the background nebula and study the subarcsecond d…
ALMA 1.3 mm Survey of Lensed Submillimeter Galaxies Selected by Herschel: Discovery of Spatially Extended SMGs and Implications
Pérez-González, Pablo G.; Richard, Johan; Smail, Ian +19 more
We present an ALMA 1.3 mm (Band 6) continuum survey of lensed submillimeter galaxies (SMGs) at z = 1.0 to ∼3.2 with an angular resolution of ∼0"2. These galaxies were uncovered by the Herschel Lensing Survey and feature exceptionally bright far-infrared continuum emission (Speak ≳ 90 mJy) owing to their lensing magnification. We detect …
Magnetic and Rotational Evolution of ρ CrB from Asteroseismology with TESS
Kochukhov, Oleg; Drake, Jeremy J.; Stassun, Keivan G. +15 more
During the first half of main-sequence lifetimes, the evolution of rotation and magnetic activity in solar-type stars appears to be strongly coupled. Recent observations suggest that rotation rates evolve much more slowly beyond middle age, while stellar activity continues to decline. We aim to characterize this midlife transition by combining arc…
Benchmarking Dust Emission Models in M101
Gordon, Karl D.; Leroy, Adam K.; Koch, Eric W. +7 more
We present a comparative study of four physical dust models and two single-temperature modified blackbody models by fitting them to the resolved WISE, Spitzer, and Herschel photometry of M101 (NGC 5457). Using identical data and a grid-based fitting technique, we compare the resulting dust and radiation field properties derived from the models. We…
An Improved Near-infrared Spectrum of the Archetype Y Dwarf WISEP J182831.08+265037.8
Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R. +8 more
We present a Hubble Space Telescope/Wide-Field Camera 3 near-infrared spectrum of the archetype Y dwarf WISEP 182831.08+265037.8. The spectrum covers the 0.9-1.7 µm wavelength range at a resolving power of λ/Δλ ≈ 180 and is a significant improvement over the previously published spectrum because it covers a broader wavelength range and is un…
One Year in the Life of Young Suns: Data-constrained Corona-wind Model of κ1 Ceti
Kochukhov, Oleg; Güdel, Manuel; Jin, Meng +5 more
The young magnetically active solar-like stars are efficient generators of ionizing radiation in the form of X-ray and extreme-UV (EUV) flux, stellar wind, and eruptive events. These outputs are the critical factors affecting atmospheric escape and chemistry of (exo)planets around active stars. While X-ray fluxes and surface magnetic fields can be…
On the Color-Metallicity Relation of the Red Clump and the Reddening toward the Magellanic Clouds
Riess, Adam G.; Yuan, Wenlong; Casagrande, Luca +2 more
The zero point of the reddening toward the Large Magellanic Cloud (LMC) has been the subject of some dispute. Its uncertainty propagates as a systematic error for methods that measure the extragalactic distance scale through knowledge of the absolute extinction of LMC stars. In an effort to resolve this issue, we used three different methods to ca…
On the Contribution of the X-Ray Source to the Extended Nebular He II Emission in IZW18
Guerrero, M. A.; Ramos-Larios, G.; Kehrig, C. +1 more
Nebular He II emission implies the presence of energetic photons (E ≥ 54 eV). Despite the great deal of effort dedicated to understanding He II ionization, its origin has remained mysterious, particularly in metal-deficient star-forming (SF) galaxies. Unfolding He II-emitting, metal-poor starbursts at z ∼ 0 can yield insight into the powerful ioni…