A5065292038- Labor Movements and Unions
- Sociology and Education Studies
- Stellar, planetary, and galactic studies
- Social Policy and Reform Studies
- Astronomy and Astrophysical Research
- European Union Policy and Governance
- Astrophysics and Star Formation Studies
- Gender, Feminism, and Media
- Astro and Planetary Science
- Economic and Social Issues
- German legal, social, and political studies
- Public Administration and Political Analysis
- Populism, Right-Wing Movements
- Music History and Culture
- European history and politics
- German Literature and Culture Studies
- Innovation, Technology, and Society
- Astronomical Observations and Instrumentation
- Communism, Protests, Social Movements
- Asian Culture and Media Studies
- European Socioeconomic and Political Studies
- Digital Games and Media
- Social Media and Politics
- Critical Theory and Philosophy
- Psychoanalysis and Social Critique
University of Bremen
2022-2024
Europa-Universität Flensburg
2017-2022
Goethe University Frankfurt
2022
Jena University Hospital
2022
Ospedale Santa Corona
2022
Universität Hamburg
2019-2021
Max Planck Institute for the Study of Societies
2012-2019
Max Planck Society
2012-2019
Leuphana University of Lüneburg
2019
Friedrich Schiller University Jena
2011-2018
The political public sphere is important for democracy, and it changing – this how the quintessence of Jürgen Habermas’s monumental study on Structural Transformation Public Sphere (1989) could be summarized in simple words. In fields sociology social theory, history, but also research movements, cultural studies, media communication his conception as a mediating between state civil society has had decisive influence debate about potential collective reason modern democracy. introduction we...
The transiting planet WASP-12 b was identified as a potential target for transit timing studies because departure from linear ephemeris reported in the literature. Such deviations could be caused by an additional system. We attempt to confirm existence of claimed variations and interpret its origin. organised multi-site campaign observe transits three observing seasons, using 0.5-2.6-metre telescopes. obtained 61 light curves, many them with sub-millimagnitude precision. simultaneous...
To understand the influence of additional wide stellar companions on planet formation, it is necessary to determine fraction multiple systems amongst known extrasolar population. We target recently discovered radial velocity exoplanetary observable from Northern hemisphere and with sufficiently high proper motion detect via direct imaging. utilize Calar Alto 2.2-m telescope in combination its lucky imaging camera AstraLux. 71 host stars have been observed so far, yielding one new low-mass...
The transiting extrasolar planet WASP-12 b was found to be one of the most intensely irradiated exoplanets. It is unexpectedly bloated and losing mass that may accrete into host star. Our aim refine parameters this intriguing system search for signs transit timing variations. We gathered high-precision light curves two transits b. Assuming various limb-darkening laws, we generated best-fitting models redetermined system. Error estimates were derived by prayer bead method Monte Carlo...
The vast majority of extrasolar planets are detected by indirect detection methods such as transit monitoring and radial velocity measurements. While these very successful in detecting short-periodic planets, they mostly blind to wide sub-stellar or even stellar companions on long orbits. In our study we present high resolution imaging observations 63 exoplanet hosts carried out with the lucky instrument AstraLux at Calar Alto 2.2m telescope well new SPHERE adaptive optics imager ESO/VLT...
There have been previous hints that the transiting planet WASP-3 b is accompanied by a second in nearby orbit, based on small deviations from strict periodicity of observed transits. Here we present 17 precise radial velocity measurements and 32 transit light curves were acquired between 2009 2011. These data used to refine parameters host star planet. This has resulted reduced uncertainties for radii masses The radial-velocity times show no evidence an additional system. Therefore,...
We present seven new widely separated companions of exoplanet host stars, detected via common proper motion, whose companionship could be confirmed with photometry, and in two cases also follow-up spectroscopy. derive the masses projected separations all companions, among them HD 107148 B, a further wide white dwarf companion an star. The current multiplicity rate stars is found to about 13 per cent.
Multi-colour broad-band transit observations offer the opportunity to characterise atmosphere of an extrasolar planet with small- medium-sized telescopes. One most favourable targets is hot Jupiter HAT-P-32 b. We combined 21 new this 36 previously published light curves for a homogeneous analysis transmission spectrum from Sloan u' band z' band. Our results rule out cloud-free planetary models solar metallicity. Furthermore, discrepancy at reddest wavelengths makes recent tentative detection...
We present the Young Exoplanet Transit Initiative (YETI), in which we use several 0.2 to 2.6m telescopes around world monitor continuously young (< 100 Myr), nearby 1 kpc) stellar clusters mainly detect transiting planets (and study other variability phenomena on time-scales from minutes years). The telescope network enables us observe targets for days order not miss any transit. runs are typically one two weeks long, about three per year cluster or subsequent years ten clusters. There...
We present the results of 45 transit observations obtained for transiting exoplanet HAT-P-32b. The transits have been observed using several telescopes mainly throughout YETI network. In 25 cases, complete light curves with a timing precision better than $1.4\:$min obtained. These used to refine system properties, namely inclination $i$, planet-to-star radius ratio $R_\textrm{p}/R_\textrm{s}$, and between semimajor axis stellar $a/R_\textrm{s}$. First analyses by Hartman et al. (2011)...
As part of our ongoing effort to investigate transit timing variations (TTVs) known exoplanets, we monitored transits the four exoplanets HAT-P-18b, HAT-P-19b, HAT-P-27b/WASP-40b and WASP-21b. All them are suspected show TTVs due properties their host systems based on respective discovery papers. During past three years 46 observations were carried out, mostly using telescopes Young Exoplanet Transit Initiative. The analyses used refine systems' orbital parameters. In all cases found no...
Although WASP-14 b is one of the most massive and densest exoplanets on a tight eccentric orbit, it has never been target photometric follow-up monitoring or dedicated observing campaigns. We report new transit observations obtained within framework Transit Timing Variations @ Young Exoplanet Initiative (TTV@YETI). collected 19 light curves 13 individual events using six telescopes located in five observatories distributed Europe Asia. From light-curve modelling, we determined planetary,...
Homogeneous observations and careful analysis of transit light curves can lead to the identification timing variations (TTVs). TrES-2 is one few exoplanets, which offer matchless possibility combine long-term ground-based with continuous satellite data. Our research aimed at search for TTVs that would be indicative perturbations from additional bodies in system. We also wanted refine system parameters orbital elements. obtained 44 31 individual events TrES-2. Eight 0.2 - 2.2-m telescopes...
CVSO 30 is a unique young low-mass system, because, for the first time, close-in transiting and wide directly imaged planet candidates are found around common host star. The inner companion, b, possible orbiting previously known weak-lined T Tauri With five telescopes of 'Young Exoplanet Transit Initiative' located in Asia, Europe South America, we monitored over three years total 144 nights detected 33 fading events. In two more seasons carried out follow-up observations with telescopes. We...
Aims. The transiting hot-Jupiter planet Qatar-1 b exhibits variations in transit times that could be perturbative. A hot Jupiter with a planetary companion on nearby orbit would constitute an unprecedented configuration, which is important for theories of the formation and evolution systems. We performed photometric follow-up campaign to confirm or refute timing variations.
We present long-term photometric observations of the young open cluster IC 348 with a baseline time-scale 2.4 yr. Our study was conducted several telescopes from Young Exoplanet Transit Initiative (YETI) network in Bessel $R$ band to find periodic variability stars. identified 87 stars be periodically variable; 33 them were unreported before. Additionally, we detected 61 non-members which 41 are new discoveries. wide field view key those numerous newly found variable The distribution...
We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4-2.2 m telescopes located west Asia, Europe, and South America. When combined literature data, they allowed us to redetermine system parameters a homogeneous way. Our results individual systems are agreement values reported previous studies. refined ephemerides reduced uncertainties of orbital periods by factor between 2 7. No sign any variations times was detected the studied.
The WASP-10 planetary system is intriguing because different values of radius have been reported for its transiting exoplanet. host star exhibits activity in terms photometric variability, which caused by the rotational modulation spots. Moreover, a periodic has discovered transit timing b, could be sign an additional body perturbing orbital motion planet. We attempt to refine physical parameters system, particular radius, crucial studying internal structure also determine new mid-transit...
Aims. The goal of our ongoing study exoplanet host stars is to determine the true multiplicity rate such stars. For this purpose we aim research a statistically significant and homogeneously analyzed sample around which planets have been found by radial velocity or transiting method. Ultimately, want if there are differences between in single- multiple-star systems. This could indicate different formation scenarios. In note, specifically investigate companionship three low-mass stellar...
We report results of the first five observing campaigns for open stellar cluster NGC 7243 in frame project Young Exoplanet Transit Initiative (YETI). The focuses on monitoring young and nearby clusters, with aim to detect transiting exoplanets, study other variability phenomena time-scales from minutes years. After additional observations during 2013 2014, a clear repeating transit-like signal was detected light curve J221550.6+495611. Furthermore, we analysed 37 new eclipsing binary stars...
Abstract We report our investigation of the first transiting planet candidate from YETI project in young (∼4 Myr old) open cluster Trumpler 37. The transit‐like signal detected lightcurve F8V star 2M21385603+5711345 repeats every 1.364894 + 0.000015 days, and has a depth 54.5 0.8 mmag R . Membership is supported by its mean radial velocity location color‐magnitude diagram, while Li diagnostic proper motion are inconclusive this regard. Follow‐up photometric monitoring adaptive optics imaging...
While globalization has led to what can – with reference Karl Polanyi be referred as a disembedding of the labour market from its nationally segmented settings, recent decades bring about development identifiable 'countermovement. As text shows, drawing on example European Works Councils and International Framework Agreements, this process 're-embedding' takes place through network different measures regulation. It is for reason that establishing relational perspective cross-border phenomena...