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Herschel Space Observatory. An ESA facility for far-infrared and submillimetre astronomy
Heras, A. M.; Pilbratt, G. L.; Metcalfe, L. +8 more
Herschel was launched on 14 May 2009, and is now an operational ESA space observatory offering unprecedented observational capabilities in the far-infrared and submillimetre spectral range 55-671 µm. Herschel carries a 3.5 m diameter passively cooled Cassegrain telescope, which is the largest of its kind and utilises a novel silicon carbide …
The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory
Lutz, D.; Altieri, B.; Andreani, P. +80 more
The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments on ESA's far infrared and submillimetre observatory. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16×25 pixels, each, and two filled silicon bolometer arrays with 16×32 and 32×64 pixels, respectively, to perform integral-fiel…
The Herschel-SPIRE instrument and its in-flight performance
Pérez-Fournon, I.; Valtchanov, I.; Ivison, R. J. +176 more
The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 µm, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 µm (447-1550…
A Survey of Stellar Families: Multiplicity of Solar-type Stars
Gies, Douglas R.; Latham, David W.; Marcy, Geoffrey W. +6 more
We present the results of a comprehensive assessment of companions to solar-type stars. A sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with π>40 mas, σπ/π < 0.05, 0.5 <= B - V <= 1.0 (~F6-K3), and constrained by absolute magnitude and color to exclude evolved stars. These criteria are equiv…
Detailed Decomposition of Galaxy Images. II. Beyond Axisymmetric Models
Ho, Luis C.; Rix, Hans-Walter; Peng, Chien Y. +1 more
We present a two-dimensional (2D) fitting algorithm (GALFIT, ver. 3) with new capabilities to study the structural components of galaxies and other astronomical objects in digital images. Our technique improves on previous 2D fitting algorithms by allowing for irregular, curved, logarithmic and power-law spirals, ring, and truncated shapes in othe…
From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt Survey
Aussel, H.; Prusti, T.; Blommaert, J. A. D. L. +54 more
We summarize the first results from the Gould Belt Survey, obtained toward the Aquila rift and Polaris Flare regions during the science demonstration phase of Herschel. Our 70-500 µm images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filament…
Spectra and Hubble Space Telescope Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
Panagia, N.; Wang, L.; Lidman, C. +43 more
We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including high signal-to-noise Hubble Space Telescope data, and spectra of six SNe Ia that were discovered during 2001, are presented. Additionally, for the two SNe with z > 1, we present ground-based J-band photometry from Gem…
The Structure and Kinematics of the Circumgalactic Medium from Far-ultraviolet Spectra of z ~= 2-3 Galaxies
Pettini, Max; Erb, Dawn K.; Shapley, Alice E. +5 more
We present new results on the kinematics and spatial distribution of metal-enriched gas within ~125 kpc of star-forming ("Lyman break") galaxies at redshifts 2 <~ z <~ 3. In particular, we focus on constraints provided by the rest-frame far-ultraviolet (far-UV) spectra of faint galaxies, and demonstrate how galaxy spectra can be used to obta…
Magnetic reconnection
Ji, Hantao; Yamada, Masaaki; Kulsrud, Russell
The fundamental physics of magnetic reconnection in laboratory and space plasmas is reviewed by discussing results from theory, numerical simulations, observations from space satellites, and recent results from laboratory plasma experiments. After a brief review of the well-known early work, representative recent experimental and theoretical works…
High molecular gas fractions in normal massive star-forming galaxies in the young Universe
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +19 more
Stars form from cold molecular interstellar gas. As this is relatively rare in the local Universe, galaxies like the Milky Way form only a few new stars per year. Typical massive galaxies in the distant Universe formed stars an order of magnitude more rapidly. Unless star formation was significantly more efficient, this difference suggests that yo…