Search Publications
Properties of Polycyclic Aromatic Hydrocarbons in the Northwest Photon Dominated Region of NGC 7023. II. Traditional PAH Analysis Using k-means as a Visualization Tool
Boersma, C.; Allamandola, L. J.; Bregman, J.
Polycyclic aromatic hydrocarbon (PAH) emission in the Spitzer-IRS spectral map of the northwest photon dominated region (PDR) in NGC 7023 is analyzed using the "traditional" approach in which the PAH bands and plateaus between 5.2-19.5 µm are isolated by subtracting the underlying continuum and removing H2 emission lines. The spec…
ALMA Observations of Warm Molecular Gas and Cold Dust in NGC 34
Sanders, D. B.; Murphy, E. J.; Armus, L. +17 more
We present Atacama Large Millimeter Array (ALMA) Cycle-0 observations of the CO (6-5) line emission (rest-frame frequency = 691.473 GHz) and of the 435 µm dust continuum emission in the nuclear region of NGC 34, a local luminous infrared galaxy at a distance of 84 Mpc (1'' = 407 pc) which contains a Seyfert 2 active galactic nucleus (AGN) an…
To Stack or Not to Stack: Spectral Energy Distribution Properties of Lyα-emitting Galaxies at z = 2.1
Finkelstein, Steven L.; Ferguson, Henry; Gronwall, Caryl +13 more
We use the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) GOODS-S multi-wavelength catalog to identify counterparts for 20 Lyα emitting (LAE) galaxies at z = 2.1. We build several types of stacked spectral energy distributions (SEDs) of these objects. We combine photometry to form average and median flux-stacked SEDs, and…
Does the Debris Disk around HD 32297 Contain Cometary Grains?
Currie, Thayne; Debes, John H.; Schneider, Glenn +13 more
We present an adaptive optics imaging detection of the HD 32297 debris disk at L' (3.8 µm) obtained with the LBTI/LMIRcam infrared instrument at the Large Binocular Telescope. The disk is detected at signal-to-noise ratio per resolution element ~3-7.5 from ~0.''3 to 1.''1 (30-120 AU). The disk at L' is bowed, as was seen at shorter wavelengt…
Distributed Low-mass Star Formation in the IRDC G34.43+00.24
Jackson, James M.; Foster, Jonathan B.; Sanhueza, Patricio +9 more
We have used deep near-infrared observations with adaptive optics to discover a distributed population of low-mass protostars within the filamentary Infrared Dark Cloud G34.43+00.24. We use maps of dust emission at multiple wavelengths to determine the column density structure of the cloud. In combination with an empirically verified model of the …
Direct Measurement of Interstellar Extinction toward Young Stars Using Atomic Hydrogen Lyα Absorption
Edwards, Suzan; Herczeg, Gregory J.; Brown, Alexander +5 more
Interstellar reddening corrections are necessary to reconstruct the intrinsic spectral energy distributions (SEDs) of accreting protostellar systems. The stellar SED determines the heating and chemical processes that can occur in circumstellar disks. Measurement of neutral hydrogen absorption against broad Lyα emission profiles in young stars can …
Herschel Observations of EXtra-Ordinary Sources: H2S as a Probe of Dense Gas and Possibly Hidden Luminosity Toward the Orion KL Hot Core
Bergin, E. A.; Crockett, N. R.; Blake, G. A. +3 more
We present Herschel/HIFI observations of the light hydride H2S obtained from the full spectral scan of the Orion Kleinmann-Low nebula (Orion KL) taken as part of the Herschel Observations of EXtra-Ordinary Sources GT (guaranteed time) key program. In total, we observe 52, 24, and 8 unblended or slightly blended features from H2
Morphological and Kinematic Evolution of Three Interacting Coronal Mass Ejections of 2011 February 13-15
Srivastava, Nandita; Mishra, Wageesh
During 2011 February 13-15, three Earth-directed coronal mass ejections (CMEs) launched in succession were recorded as limb CMEs by STEREO/SECCHI coronagraphs (COR). These CMEs provided an opportunity to study their geometrical and kinematic evolution from multiple vantage points. In this paper, we examine the differences in geometrical evolution …
Diffusion of Magnetic Elements in a Supergranular Cell
Bellot Rubio, L.; Giannattasio, F.; Berrilli, F. +2 more
Small scale magnetic fields (magnetic elements) are ubiquitous in the solar photosphere. Their interaction can provide energy to the upper atmospheric layers, and contribute to heat the solar corona. In this work, the dynamic properties of magnetic elements in the quiet Sun are investigated. The high number of magnetic elements detected in a super…
Search for Surviving Companions in Type Ia Supernova Remnants
Pan, Kuo-Chuan; Ricker, Paul M.; Taam, Ronald E.
The nature of the progenitor systems of type Ia supernovae (SNe Ia) is still unclear. One way to distinguish between the single-degenerate scenario and double-degenerate scenario for their progenitors is to search for the surviving companions (SCs). Using a technique that couples the results from multi-dimensional hydrodynamics simulations with ca…