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Ionized Gas Motions and the Structure of Feedback near a Forming Globular Cluster in NGC 5253
Turner, Jean L.; Beck, Sara C.; Martin, Emily C. +2 more
We observed Brackett α 4.05 µm emission toward the supernebula in NGC 5253 with NIRSPEC on Keck II in adaptive optics mode, NIRSPAO, to probe feedback from its exciting embedded super star cluster (SSC). NIRSPEC's Slit-viewing Camera was simultaneously used to image the K-band continuum at ∼0.″1 resolution. We register the IR continuum with …
Exploring the Origins of Earth’s Nitrogen: Astronomical Observations of Nitrogen-bearing Organics in Protostellar Environments
Bergin, Edwin A.; Wampfler, S. F.; Jørgensen, Jes K. +1 more
It is not known whether the original carriers of Earth’s nitrogen were molecular ices or refractory dust. To investigate this question, we have used data and results of Herschel observations toward two protostellar sources: the high-mass hot core of Orion KL, and the low-mass protostar IRAS 16293-2422. Toward Orion KL, our analysis of the molecula…
Circumgalactic Gas at Its Extreme: Tidal Gas Streams around the Whale Galaxy NGC 4631 Explored with HST/COS
Wakker, B. P.; Gentile, G.; Winkel, B. +8 more
We present a detailed analysis of the absorption properties of one of the tidal gas streams around the “Whale” galaxy NGC 4631 in the direction of the quasar 2MASS J12421031+3214268. Our study is based on ultraviolet spectral data obtained with the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST) and 21cm-data from the H…
Does Nearby Open Flux Affect the Eruptivity of Solar Active Regions?
DeRosa, Marc L.; Barnes, Graham
The most energetic solar flares are typically associated with the ejection of a cloud of coronal material into the heliosphere in the form of a coronal mass ejection (CME). However, large flares exist that are not accompanied by a CME. The existence of these noneruptive flares raises the question of whether such flares suffer from a lack of access…
The Envelope Kinematics and a Possible Disk around the Class 0 Protostar within BHR7
Bourke, Tyler L.; Dunham, Michael M.; Tobin, John J. +2 more
We present a characterization of the protostar embedded within the BHR7 dark cloud, based on both photometric measurements from the near-infrared to millimeter and interferometric continuum and molecular line observations at millimeter wavelengths. We find that this protostar is a Class 0 system, the youngest class of protostars, measuring its bol…
Bright Network, UVA, and the Physical Modeling of Solar Spectral and Total Irradiance in Recent Solar Cycles
Fontenla, J. M.; Landi, E.
In this paper we study the total solar irradiance (TSI) and the spectral solar irradiance (SSI) by applying the solar disk image decomposition algorithm (SDIDA) and solar irradiance synthesis algorithm (SISA) methods. These methods were applied to space-based observations in previous works, but in this work, they are applied to ground-based observ…
Quantifying Turbulent Dynamics Found within the Plasma Sheets of Multiple Solar Flares
McKenzie, David E.; Freed, Michael S.
It is vital to our understanding of solar flares that we discern how turbulent motion can affect the magnetic reconnection process. The objective of this study is to quantify the velocity and vorticity structures inherent in the observed motions found in a plasma sheet above arcades during a solar flare. The most noticeable features in these plasm…
The Advanced Spectral Library (ASTRAL): Reference Spectra for Evolved M Stars
Ayres, Thomas R.; Carpenter, Kenneth G.; Nielsen, Krister E. +3 more
The HST Treasury Program Advanced Spectral Library Project: Cool Stars was designed to collect representative, high-quality UV spectra of eight evolved F-M type cool stars. The Space Telescope Imaging Spectrograph (STIS) echelle spectra of these objects enable investigations of a broad range of topics, including stellar and interstellar astrophysi…
The Long-term Secular Mass Accretion Rate of the Recurrent Nova T Pyxidis
Williams, Robert E.; Sion, Edward M.; Godon, Patrick +1 more
We present Hubble Space Telescope ultraviolet spectroscopy of the recurrent nova T Pyxidis obtained more than five years after its 2011 outburst, indicating that the system might not have yet reached its deep quiescent state. The ultraviolet data exhibit a 20% decline in the continuum flux from the pre-outburst deep quiescence state to the post-ou…
Possible Association of Two Stellar Bowshocks with Unidentified Fermi Sources
Luque-Escamilla, P. L.; Romero, G. E.; Martí, J. +2 more
The bowshocks of runaway stars had been theoretically proposed as gamma-ray sources. However, this hypothesis has not been confirmed by observations to date. In this paper, we present two runaway stars (λ Cep and LS 2355) whose bowshocks are coincident with the unidentified Fermi gamma-ray sources 3FLG J2210.1+5925 and 3FGL J1128.7-6232, respectiv…