Constraints on the Equation-of-State of neutron stars from nearby neutron star observations

We try to constrain the Equation-of-State (EoS) of supra-nuclear-density matter in neutron stars (NSs) by observations of nearby NSs. There are seven thermally emitting NSs known from X-ray and optical observations, the so-called Magnificent Seven (M7), which are young (up to few Myrs), nearby (within a few hundred pc), and radio-quiet with blackbody-like X-ray spectra, so that we can observe their surfaces. As bright X-ray sources, we can determine their rotational (pulse) period and their period derivative from X-ray timing. From XMM and/or Chandra X-ray spectra, we can determine their temperature. With precise astrometric observations using the Hubble Space Telescope, we can determine their parallax (i.e. distance) and optical flux. From flux, distance, and temperature, one can derive the emitting area - with assumptions about the atmosphere and/or temperature distribution on the surface. This was recently done by us for the two brightest M7 NSs RXJ1856 and RXJ0720. Then, from identifying absorption lines in X-ray spectra, one can also try to determine gravitational redshift. Also, from rotational phase-resolved spectroscopy, we have for the first time determined the compactness (mass/radius) of the M7 NS RBS1223. If also applied to RXJ1856, radius (from luminosity and temperature) and compactness (from X-ray data) will yield the mass and radius - for the first time for an isolated single neutron star. We will present our observations and recent results.Comment: refereed NPA5 conference proceedings, in pres

On identifying the neutron star that was born in the supernova that placed 60Fe onto the Earth

Recently, 60Fe was found in the Earth crust formed in a nearby recent supernova (SN). If the distance to the SN and mass of the progenitor of that SN was known, then one could constrain SN models. Knowing the positions, proper motions, and distances of dozens of young nearby neutron stars, we can determine their past flight paths and possible kinematic origin. Once the birth place of a neutron star in a SN is found, we would have determined the distance of the SN and the mass of the SN progenitor star.Comment: refereed NPA5 conference proceedings, in pres

Morphological paradigms in language processing and language disorders

We present results from two cross‐modal morphological priming experiments investigating regular person and number inflection on finite verbs in German. We found asymmetries in the priming patterns between different affixes that can be predicted from the structure of the paradigm. We also report data from language disorders which indicate that inflectional errors produced by language‐impaired adults and children tend to occur within a given paradigm dimension, rather than randomly across the paradigm. We conclude that morphological paradigms are used by the human language processor and can be systematically affected in language disorders

Putting things in places: Developmental consequences of linguistic typology

This study explores how adults and children describe placement events (e.g., putting a book on a table) in a range of different languages (Finnish, English, German, Russian, Hindi, Tzeltal Maya, Spanish, and Turkish). Results show that the eight languages grammatically encode placement events in two main ways (Talmy, 1985, 1991), but further investigation reveals fine-grained crosslinguistic variation within each of the two groups. Children are sensitive to these finer-grained characteristics of the input language at an early age, but only when such features are perceptually salient. Our study demonstrates that a unitary notion of 'event' does not suffice to characterize complex but systematic patterns of event encoding crosslinguistically, and that children are sensitive to multiple influences, including the distributional properties of the target language, in constructing these patterns in their own speech

The Hercules-Lyra Association revisited New age estimation and multiplicity study

The Her-Lyr assoc., a nearby young MG, contains a few tens of ZAMS stars of SpT F to M. The existence and the properties of the Her-Lyr assoc. are controversial and discussed in the literature. The present work reassesses properties and the member list of Her-Lyr assoc., based on kinematics and age. Many objects form multiple systems or have low-mass companions and so we need to account for multiplicity. We use our own new imaging obs. and archival data to identify multiple systems. The colors and magnitudes of kinematic candidates are compared to isochrones. We derive further information on the age based on Li depletion, rotation, and coronal and chromospheric activity. A set of canonical members is identified to infer mean properties. Membership criteria are derived from the mean properties and used to discard non-members. The candidates selected from the literature belong to 35 stellar systems, 42.9% of which are multiple. Four multiple systems are confirmed in this work by common proper motion. An orbital solution is presented for the binary system HH Leo B and C. Indeed, a group of candidates displays signatures of youth. 7 canonical members are identified. The distribution of EWLi of canonical Her-Lyr members is spread widely and is similar to that of the Pleiades and the UMa group. Gyrochronology gives an age of 257+-46 Myr which is in between the ages of the Pleiades and the Ursa Major group. The measures of chromospheric and coronal activity support the young age. Four membership criteria are presented based on kinematics, EWLi, chromospheric activity, and gyro. age. In total, 11 stars are identified as certain members including co-moving objects plus additional 23 possible members while 14 candidates are doubtful or can be rejected. A comparison to the mass function, however, indicates the presence of a large number of additional unidentified low-mass members.Comment: 19 pages 16 figure

Transit observations at the observatory in Grossschwabhausen: XO-1b and TrES-1

We report on observations of transit events of the transiting planets XO-1b and TrES-1 with the AIU Jena telescope in Grossschwabhausen. Based on our IR photometry (in March 2007) and available transit timings (SuperWASP, XO and TLC-project-data) we improved the orbital period of XO-1b (P = 3.941497$\pm$0.000006) and TrES-1 (P = 3.0300737$\pm$0.000006), respectively. The new ephemeris for the both systems are presented.Comment: 4 pages, 2 figure

Variability of young stars: Determination of rotational periods of weak-line T Tauri stars in the Cepheus-Cassiopeia star-forming region

We report on observation and determination of rotational periods of ten weak-line T Tauri stars in the Cepheus-Cassiopeia star-forming region. Observations were carried out with the Cassegrain-Teleskop-Kamera (CTK) at University Observatory Jena between 2007 June and 2008 May. The periods obtained range between 0.49 d and 5.7 d, typical for weak-line and post T Tauri stars.Comment: 11 pages, 26 figures, accepted to be published in A

WASP-14 b: Transit Timing analysis of 19 light curves

Although WASP-14 b is one of the most massive and densest exoplanets on a tight and eccentric orbit, it has never been a target of photometric follow-up monitoring or dedicated observing campaigns. We report on new photometric transit observations of WASP-14 b obtained within the framework of "Transit Timing Variations @ Young Exoplanet Transit Initiative" (TTV@YETI). We collected 19 light-curves of 13 individual transit events using six telescopes located in five observatories distributed in Europe and Asia. From light curve modelling, we determined the planetary, stellar, and geometrical properties of the system and found them in agreement with the values from the discovery paper. A test of the robustness of the transit times revealed that in case of a non-reproducible transit shape the uncertainties may be underestimated even with a wavelet-based error estimation methods. For the timing analysis we included two publicly available transit times from 2007 and 2009. The long observation period of seven years (2007-2013) allowed us to refine the transit ephemeris. We derived an orbital period 1.2 s longer and 10 times more precise than the one given in the discovery paper. We found no significant periodic signal in the timing-residuals and, hence, no evidence for TTV in the system.Comment: 12 pages, 10 figures, 7 table