Search Publications
The Dynamical Masses, Densities, and Star Formation Scaling Relations of Lyα Galaxies
Finkelstein, Steven L.; Fynbo, Johan P. U.; Malhotra, Sangeeta +4 more
We present the first dynamical mass measurements for Lyα galaxies at high redshift, based on velocity dispersion measurements from rest-frame optical emission lines and size measurements from Hubble Space Telescope imaging, for nine galaxies drawn from four surveys. We use these measurements to study Lyα galaxies in the context of galaxy scaling r…
The Water Abundance behind Interstellar Shocks: Results from Herschel/PACS and Spitzer/IRS Observations of H2O, CO, and H2
Nisini, Brunella; van Dishoeck, Ewine F.; Güsten, Rolf +7 more
We have investigated the water abundance in shock-heated molecular gas, making use of Herschel measurements of far-infrared (IR) CO and H2O line emissions in combination with Spitzer measurements of mid-IR H2 rotational emissions. We present far-IR line spectra obtained with Herschel's Photodetector Array Camera and Spectrome…
Measuring the Stellar Masses of z ~ 7 Galaxies with the Spitzer UltRaFaint SUrvey Program (SURFS UP)
Schrabback, T.; Bradač, M.; Huang, K. -H. +15 more
We present Spitzer/IRAC observations of nine z'-band dropouts highly magnified (2 <~ µ <~ 12) by the Bullet Cluster. We combine archival imaging with our Exploratory program (SURFS UP), which results in a total integration time of ~30 hr per Infrared Array Camera (IRAC) band. We detect (gsim 3σ) in both IRAC bands the brightest of thes…
Evolution and Dynamics of Orphan Penumbrae in the Solar Photosphere: Analysis from Multi-instrument Observations
Guglielmino, Salvo L.; Romano, Paolo; Zuccarello, Francesca
We investigate the dynamics and magnetic properties of orphan penumbrae observed in the solar photosphere to understand the formation process of such structures. We observed two orphan penumbrae in active region NOAA 11089 during a coordinated observing campaign carried out in 2010 July, involving the Hinode/Solar Optical Telescope (SOT) and Dutch…
The Mass Distribution of the Strong Lensing Cluster SDSS J1531+3414
Rigby, Jane R.; Sharon, Keren; Johnson, Traci L. +5 more
We present the mass distribution at the core of SDSS J1531+3414, a strong-lensing cluster at z = 0.335. We find that the mass distribution is well described by two cluster-scale halos with a contribution from cluster-member galaxies. New Hubble Space Telescope observations of SDSS J1531+3414 reveal a signature of ongoing star formation associated …
Widespread Rotationally Hot Hydronium Ion in the Galactic Interstellar Medium
Godard, B.; Le Petit, F.; Comito, C. +11 more
We present new Herschel observations of the (6,6) and (9,9) inversion transitions of the hydronium ion toward Sagittarius B2(N) and W31C. Sensitive observations toward Sagittarius B2(N) show that the high, ~500 K, rotational temperatures characterizing the population of the highly excited metastable H3O+ rotational levels are…
Deriving Stellar Inclination of Slow Rotators Using Stellar Activity
Dumusque, X.
Stellar inclination is an important parameter for many astrophysical studies. Although different techniques allow us to estimate stellar inclination for fast rotators, it becomes much more difficult when stars are rotating slower than ~2-2.5 km s-1. By using the new activity simulation SOAP 2.0 which can reproduce the photometric and sp…
Mass Transport around Comets and its Impact on the Seasonal Differences in Water Production Rates
Altwegg, K.; Thomas, N.; Combi, M. R. +4 more
Comets are surrounded by a thin expanding atmosphere, and although the nucleus' gravity is small, some molecules and grains, possibly with the inclusion of ices, can get transported around the nucleus through scattering (atoms/molecules) and gravitational pull (grains). Based on the obliquity of the comet, it is also possible that volatile materia…
Structure and Dynamics of the Accretion Process and Wind in TW Hya
Strader, Jay; Cranmer, S. R.; Smith, Graeme H. +3 more
Time-domain spectroscopy of the classical accreting T Tauri star, TW Hya, covering a decade and spanning the far UV to the near-infrared spectral regions can identify the radiation sources, the atmospheric structure produced by accretion, and properties of the stellar wind. On timescales from days to years, substantial changes occur in emission li…
The Heating of Mid-infrared Dust in the Nearby Galaxy M33: A Testbed for Tracing Galaxy Evolution
Calzetti, Daniela; Boquien, Médéric; van der Werf, Paul +10 more
Infrared emission is an invaluable tool for quantifying star formation in galaxies. Because the 8 µm polycyclic aromatic hydrocarbon (PAH) emission has been found to correlate with other well-known star formation tracers, it has widely been used as a star formation rate (SFR) tracer. There are, however, studies that challenge the accuracy an…