Search Publications
Absorption-line Detections of 105-106 K Gas in Spiral-rich Groups of Galaxies
Kacprzak, Glenn G.; Savage, Blair D.; Shull, J. Michael +10 more
Using the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, the COS Science Team has conducted a high signal-to-noise survey of 14 bright QSOs. In a previous paper, these far-UV spectra were used to discover 14 "warm" (T >= 105 K) absorbers using a combination of broad Lyα and broad O VI absorptions. A reanalysis of a …
Star Formation Rates from [C II] 158 µm and Mid-infrared Emission Lines for Starbursts and Active Galactic Nuclei
Lebouteiller, V.; Sargsyan, L.; Samsonyan, A. +5 more
A summary is presented for 130 galaxies observed with the Herschel Photodetector Array Camera and Spectrometer instrument to measure fluxes for the [C II] 158 µm emission line. Sources cover a wide range of active galactic nucleus to starburst classifications, as derived from polycyclic aromatic hydrocarbon strength measured with the Spitzer…
A Solar Type II Radio Burst from Coronal Mass Ejection-Coronal Ray Interaction: Simultaneous Radio and Extreme Ultraviolet Imaging
Feng, Li; Li, Gang; Chen, Yao +5 more
Simultaneous radio and extreme ultraviolet (EUV)/white-light imaging data are examined for a solar type II radio burst occurring on 2010 March 18 to deduce its source location. Using a bow-shock model, we reconstruct the three-dimensional EUV wave front (presumably the type-II-emitting shock) based on the imaging data of the two Solar TErrestrial …
Hubble Space Telescope/Cosmic Origins Spectrograph Observations of the Quasar Q0302-003: Probing the He II Reionization Epoch and QSO Proximity Effects
Shull, J. Michael; Syphers, David
Q0302-003 (z = 3.2860 ± 0.0005) was the first quasar discovered that showed a He II Gunn-Peterson trough, a sign of incomplete helium reionization at z >~ 2.9. We present its Hubble Space Telescope/Cosmic Origins Spectrograph far-UV medium-resolution spectrum, which resolves many spectral features for the first time, allowing study of the quasa…
The Very Faint End of the UV Luminosity Function over Cosmic Time: Constraints from the Local Group Fossil Record
Conroy, Charlie; Johnson, Benjamin D.; Weisz, Daniel R.
We present a new technique to estimate the evolution of the very faint end of the UV luminosity function (LF) out to z ~ 5. Measured star formation histories (SFHs) from the fossil record of Local Group (LG) galaxies are used to reconstruct the LF down to M UV ~-5 at z ~ 5 and M UV ~-1.5 at z < 1. Such faint limits are wel…
Direct Observations of Magnetic Flux Rope Formation during a Solar Coronal Mass Ejection
Chen, Y.; Song, H. Q.; Cheng, X. +1 more
Coronal mass ejections (CMEs) are the most spectacular eruptive phenomena in the solar atmosphere. It is generally accepted that CMEs are the results of eruptions of magnetic flux ropes (MFRs). However, there is heated debate on whether MFRs exist prior to the eruptions or if they are formed during the eruptions. Several coronal signatures, e.g., …
A Spectroscopic Sample of Massive, Quiescent z ~ 2 Galaxies: Implications for the Evolution of the Mass-Size Relation
Brammer, G.; Toft, S.; Man, A. +2 more
We present deep, near-infrared Hubble Space Telescope/Wide Field Camera 3 grism spectroscopy and imaging for a sample of 14 galaxies at z ≈ 2 selected from a mass-complete photometric catalog in the COSMOS field. By combining the grism observations with photometry in 30 bands, we derive accurate constraints on their redshifts, stellar masses, ages…
Revealing H2D+ Depletion and Compact Structure in Starless and Protostellar Cores with ALMA
Di Francesco, J.; Bourke, T. L.; Caselli, P. +4 more
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the submillimeter dust continuum and H2D+ 110-111 emission toward two evolved, potentially protostellar cores within the Ophiuchus molecular cloud, Oph A SM1 and SM1N. The data reveal small-scale condensations within both core…
Tracking the CME-driven Shock Wave on 2012 March 5 and Radio Triangulation of Associated Radio Emission
Mierla, M.; Zhukov, A. N.; Magdalenić, J. +5 more
We present a multiwavelength study of the 2012 March 5 solar eruptive event, with an emphasis on the radio triangulation of the associated radio bursts. The main points of the study are reconstruction of the propagation of shock waves driven by coronal mass ejections (CMEs) using radio observations and finding the relative positions of the CME, th…
Simulating the Formation of a Sigmoidal Flux Rope in AR10977 from SOHO/MDI Magnetograms
Green, L. M.; Gibb, G. P. S.; Mackay, D. H. +1 more
The modeling technique of Mackay et al. is applied to simulate the coronal magnetic field of NOAA active region AR10977 over a seven day period (2007 December 2-10). The simulation is driven with a sequence of line-of-sight component magnetograms from SOHO/MDI and evolves the coronal magnetic field though a continuous series of non-linear force-fr…