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© 2011 The American Astronomical Society. This wor0k is partially funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC. J. M. M. acknowledges funding from a Graduate Alumni Fellowship at the University of Florida. The Spanish MICINN provides support to M. B., M. P., and A. H. through grant AYA2009-11137 and to J. G. through grant AYA2009-10368. Our observations were made with the GTC Telescope at the Spanish Observatorio del Roque de los Muchachos, which is managed by the Instituto de Astrofísica de Canarias. We are grateful to the personnel who took the observations and to Ana Matkovic for her help with the use of the REDucmE software. We also thank the anonymous referee for useful comments that improved the presentation of this Letter., We present Gran-Telescopio-Canarias/OSIRIS optical spectra of four of the most compact and massive early-type galaxies (ETGs) in the Groth Strip Survey at redshift z similar to 1, with effective radii R-e = 0.5-2.4 kpc and photometric stellarmasses M-star = (1.2-4) x 10(11)M(circle dot). We find that these galaxies have velocity dispersions sigma = 156-236 km s(-1). The spectra are well fitted by single stellar population models with approximately 1 Gyr of age and solar metallicity. We find that (1) the dynamical masses of these galaxies are systematically smaller by a factor of similar to 6 than the published stellarmasses using BRIJK photometry, and (2) when estimating stellarmasses as 0.7xM(dyn), a combination of passive luminosity fading with mass/size growth due to minor mergers can plausibly evolve our objects to match the properties of the local population of ETGs., Spanish MICINN, University of Florida, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

Context. The occurrence rate and period distribution of (giant) planets around young stars is still not as well constrained as for older main-sequence stars. This is mostly due to the intrinsic activity-related complications and the avoidance of young stars in many large planet search programmes. Yet, dynamical restructuring processes in planetary systems may last significantly longer than the actual planet formation phase and may well extend long into the debris disc phase, such that the planet populations around young stars may differ from those observed around main-sequence stars. Aims. We introduce our Radial Velocity Survey for Planets around Young stars (RVSPY), which is closely related to the NaCo-ISPY direct imaging survey, characterise our target stars, and search for substellar companions at orbital separations smaller than a few au from the host star. Methods. We used the FEROS spectrograph, mounted to the MPG/ESO 2.2 m telescope in Chile, to obtain high signal-to-noise spectra and time series of precise radial velocities (RVs) of 111 stars, most of which are surrounded by debris discs. Our target stars have spectral types between early F and late K, a median age of 400 Myr, and a median distance of 45 pc. During the initial reconnaissance phase of our survey, we determined stellar parameters and used high-cadence observations to characterise the intrinsic stellar activity, searched for hot companions with orbital periods of up to 10 days, and derived the detection thresholds for longer-period companions. In our analysis we, have included archival spectroscopic data, spectral energy distribution, and data for photometric time series from the TESS mission. Results. For all target stars we determined their basic stellar parameters and present the results of the high-cadence RV survey and activity characterisation. We have achieved a median single-measurement RV precision of 6 m s−1 and derived the short-term intrinsic RV scatter of our targets (median 23 m

We present the results obtained from our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z∼6-11

A catalogue of galaxies with extremely red colours (R-J≥5), covering 8.43 square degrees has been selected from optical and near-infrared data. Based on their bright near-infrared magnitude and their very red colour, these objects are likely to be very massive galaxies with little or no ongoing star formation. We have derived a surface density of 0.0396 ± 0.0011 arcmin⁻² (Poisson uncertainties) for these Extremely Red Objects.

Abstrakt Im Rahmen dieser Arbeit wurde ein Doppelkristalldiffraktometer aufgebaut, das unter anderem auch fuer Kleinwinkelstreuunter- suchungen an poroesen Materialien, fuer die Untersuchung neutronenoptischer Komponenten und von Beugungs- und Brechungserscheinungen an magnetischen Domaenen eingesetzt werden kann. Das Doppelkristalldiffraktometer setzt sich aus zwei perfekten Siliciumeinkristallen mit einer asymmetrischen Anordnung zusammen, die variabel kruemmbar sind. Durch die Kruemmung des Analysators kann in einem Q-Bereich von 1*10-4 nm-1 bis 2*10-1 nm-1 und durch die Kruemmung des Monochromators mit einer Aufloesung von 1.5*10-4 nm-1 bis 4.5*10-3 nm-1 gemessen werden. Dadurch ist es moeglich, Messungen ueber einen grossen Q-Bereich an einem Geraet durchzufuehren. Durch die Verwendung eines ortsaufloesenden Detektors kann das gesamte Spektrum simultan erfasst werden, dadurch sind zeitaufgeloeste Messungen von einigen Minuten moeglich. In der Dissertation wurde die zeitliche Entwicklung der inneren Struktur von Zementstein waehrend der Hydratation unter dem Einfluss unterschiedlicher Temperaturen und verschiedener Luftfeuchtigkeiten untersucht. Die beiden Parameter beeinflussen ueber die Struktur des Zementsteins die bautechnischen Eigenschaften, wie Festigkeit, Korrosionsbestaendigkeit und Durchlaessigkeit fuer Flaessigkeiten und Gase. Der Einfluss dieser beiden Parameter auf die Teilchengroessenverteilung wurde ueber einen Zeitraum bis zu 260 Tagen verfolgt. Dabei wurde die Temperatur in einem Bereich von 10oC bis 50oC bei einer relativen Luftfeuchte von 76% variiert. Die Untersuchungen zum Einfluss der relativen Luftfeuchtigkeit auf die Strukturentwicklung fanden bei einer Umgebungstemperatur von 23oC statt, die relative Luftfeuchtigkeit variierte zwischen 11%, 56%, 76% und 100%. Schlagwoerter: Neutronenkleinwinkelstreuung; Groessenverteilungsfunktion; Doppelkristall- diffraktometer; Parameterbestimmung; System Zementstein; Hydratation; Einflussgroessen; Str

We present the results obtained from our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z∼6-11