{"id":{"repo_id":"heid-diss","oai_identifier":"oai:archiv.ub.uni-heidelberg.de:5453"},"canonical_url":"https://search.dev.ndltd.org/etd/heid-diss/oai:archiv.ub.uni-heidelberg.de:5453","repository":{"repo_id":"heid-diss","name":"Universität Heidelberg","base_url":"http://archiv.ub.uni-heidelberg.de/volltextserver/cgi/oai2"},"display":{"title":"High-resolution studies of protoplanetary disks","abstract":"This work presents a multi-wavelength search (near-IR, mid-IR, mm) for previously unknown circumstellar disks and a study of those disk candidate objects which are not yet well characterised in the literature. 22 candidate stars, most of these constituting known exoplanet systems, were examined for circumstellar material using the Adaptive Optics instrument ADONIS at La Silla Observatory (Chile). With the new Adaptive Optics system NAOS-CONICA at Paranal (Chile) we tested the technique of Polarimetric Differential Imaging. Advances in mid-IR data reduction were achieved, e.g., a method was developed to correct the chromatic and airmass dependent extinction. We show new N-band photometry and spectra for eight pre-main sequence stars, six main sequence stars and one post-MS object using the TIMMI2 camera at La Silla, and model the emission spectra with a mixture of silicates consisting of different grain sizes and composition. The most important result thereof is the discovery of two previously unknown circumstellar disks around HD 72106 and HD 113766. Both objects are host to highly processed silicates, resembling those found in solar-system comets. We further present the first observational confirmation for an extended circumstellar dust disk around epsilon Eri obtained with the bolometer array SIMBA at the 15m radio telescope SEST in La Silla and demonstrate that the previously claimed disk substructure may alternatively be explained by remnant noise effects.","abstract_html":"This work presents a multi-wavelength search (near-IR, mid-IR, mm) for previously unknown circumstellar disks and a study of those disk candidate objects which are not yet well characterised in the literature. 22 candidate stars, most of these constituting known exoplanet systems, were examined for circumstellar material using the Adaptive Optics instrument ADONIS at La Silla Observatory (Chile). With the new Adaptive Optics system NAOS-CONICA at Paranal (Chile) we tested the technique of Polarimetric Differential Imaging. Advances in mid-IR data reduction were achieved, e.g., a method was developed to correct the chromatic and airmass dependent extinction. We show new N-band photometry and spectra for eight pre-main sequence stars, six main sequence stars and one post-MS object using the TIMMI2 camera at La Silla, and model the emission spectra with a mixture of silicates consisting of different grain sizes and composition. The most important result thereof is the discovery of two previously unknown circumstellar disks around HD 72106 and HD 113766. Both objects are host to highly processed silicates, resembling those found in solar-system comets. We further present the first observational confirmation for an extended circumstellar dust disk around epsilon Eri obtained with the bolometer array SIMBA at the 15m radio telescope SEST in La Silla and demonstrate that the previously claimed disk substructure may alternatively be explained by remnant noise effects.","abstract_has_math":false,"creators":["Schütz, Oliver"],"institution":"Universität Heidelberg","degree_name":null,"degree_level":"thesis.doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Henning, Thomas"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2005,"date_issued":"2005-02-09","date_published":"2005-02-09","updated_at":"2026-07-24T02:30:04Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://www.ub.uni-heidelberg.de/archiv/5453","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Henning, Thomas"]},{"key":"dc:creator","label":"Author","values":["Schütz, Oliver"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:publisher","label":"Institution","values":["Universitätsbibliothek Heidelberg"]},{"key":"dc:type","label":"Dc Type","values":["doctoralThesis"]},{"key":"thesis:degree_level","label":"Degree Level","values":["thesis.doctoral"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Universität Heidelberg"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This work presents a multi-wavelength search (near-IR, mid-IR, mm) for previously unknown circumstellar disks and a study of those disk candidate objects which are not yet well characterised in the literature. 22 candidate stars, most of these constituting known exoplanet systems, were examined for circumstellar material using the Adaptive Optics instrument ADONIS at La Silla Observatory (Chile). With the new Adaptive Optics system NAOS-CONICA at Paranal (Chile) we tested the technique of Polarimetric Differential Imaging. Advances in mid-IR data reduction were achieved, e.g., a method was developed to correct the chromatic and airmass dependent extinction. We show new N-band photometry and spectra for eight pre-main sequence stars, six main sequence stars and one post-MS object using the TIMMI2 camera at La Silla, and model the emission spectra with a mixture of silicates consisting of different grain sizes and composition. The most important result thereof is the discovery of two previously unknown circumstellar disks around HD 72106 and HD 113766. Both objects are host to highly processed silicates, resembling those found in solar-system comets. We further present the first observational confirmation for an extended circumstellar dust disk around epsilon Eri obtained with the bolometer array SIMBA at the 15m radio telescope SEST in La Silla and demonstrate that the previously claimed disk substructure may alternatively be explained by remnant noise effects.","Die vorliegende Arbeit beschreibt eine Suche nach neuen, noch unbekannten circumstellaren Staub-Scheiben im nahen und thermischen Infrarot sowie im Millimeter-Bereich. Ferner studieren wir mutmaßliche Scheiben, die in der Literatur erst unzureichend beschrieben sind. 22 Sterne, die zum Teil eine Scheibe besitzen könnten, wurden mit Adaptiver Optik (AO) und der Kamera ADONIS am Observatorium La Silla (Chile) untersucht. Mit dem AO-System NAOS-CONICA am Paranal (Chile) testen wir eine neue Nachweismethode für Scheiben: Differenzielle Polarimetrie. Für die Reduktion von Daten des thermischen Infrarots haben wir neue Methoden entwickelt, z.B. eine Möglichkeit die chromatische und von der Luftmasse abhängige Extinktion zu korrigieren. Wir zeigen bisher unveröffentlichte N-Band Photometrie und Spektren - aufgenommen mit der TIMMI2 Kamera in La Silla - für acht Vor-Hauptreihensterne, sechs Sterne der Hauptreihe und ein Objekt am Ende des Hauptreihenstadiums. Die Emissionsspektren modellieren wir mit bekannten Spektren von Silikaten verschiedener Zusammensetzung und Größe. Bei diesen Untersuchungen wurden bisher unbekannte Scheiben um die Sterne HD 72106 und HD 113766 gefunden. Beide Scheiben beinhalten Silikate in einem sehr weit fortgeschrittenen Entwicklungszustand, ähnlich jenen in Kometen unseres Sonnensystems. Wir zeigen ferner die erste Bestätigung einer großen Scheibe um epsilon Eri anhand von Daten, die mit dem Bolometer Array SIMBA am 15m Radioteleskop SEST in La Silla gewonnen wurden. Die aus früheren Beobachtungen gefolgerte innere Struktur dieser Scheibe kann alternativ aber auch durch Rauscheffekte erklärt werden."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["High-resolution studies of protoplanetary disks","Hochauflösende Untersuchungen protoplanetarer Scheiben"]}]}],"canonical_facts":{"dc:contributor":["Henning, Thomas"],"dc:creator":["Schütz, Oliver"],"dc:description.abstract":["This work presents a multi-wavelength search (near-IR, mid-IR, mm) for previously unknown circumstellar disks and a study of those disk candidate objects which are not yet well characterised in the literature. 22 candidate stars, most of these constituting known exoplanet systems, were examined for circumstellar material using the Adaptive Optics instrument ADONIS at La Silla Observatory (Chile). With the new Adaptive Optics system NAOS-CONICA at Paranal (Chile) we tested the technique of Polarimetric Differential Imaging. Advances in mid-IR data reduction were achieved, e.g., a method was developed to correct the chromatic and airmass dependent extinction. We show new N-band photometry and spectra for eight pre-main sequence stars, six main sequence stars and one post-MS object using the TIMMI2 camera at La Silla, and model the emission spectra with a mixture of silicates consisting of different grain sizes and composition. The most important result thereof is the discovery of two previously unknown circumstellar disks around HD 72106 and HD 113766. Both objects are host to highly processed silicates, resembling those found in solar-system comets. We further present the first observational confirmation for an extended circumstellar dust disk around epsilon Eri obtained with the bolometer array SIMBA at the 15m radio telescope SEST in La Silla and demonstrate that the previously claimed disk substructure may alternatively be explained by remnant noise effects.","Die vorliegende Arbeit beschreibt eine Suche nach neuen, noch unbekannten circumstellaren Staub-Scheiben im nahen und thermischen Infrarot sowie im Millimeter-Bereich. Ferner studieren wir mutmaßliche Scheiben, die in der Literatur erst unzureichend beschrieben sind. 22 Sterne, die zum Teil eine Scheibe besitzen könnten, wurden mit Adaptiver Optik (AO) und der Kamera ADONIS am Observatorium La Silla (Chile) untersucht. Mit dem AO-System NAOS-CONICA am Paranal (Chile) testen wir eine neue Nachweismethode für Scheiben: Differenzielle Polarimetrie. Für die Reduktion von Daten des thermischen Infrarots haben wir neue Methoden entwickelt, z.B. eine Möglichkeit die chromatische und von der Luftmasse abhängige Extinktion zu korrigieren. Wir zeigen bisher unveröffentlichte N-Band Photometrie und Spektren - aufgenommen mit der TIMMI2 Kamera in La Silla - für acht Vor-Hauptreihensterne, sechs Sterne der Hauptreihe und ein Objekt am Ende des Hauptreihenstadiums. Die Emissionsspektren modellieren wir mit bekannten Spektren von Silikaten verschiedener Zusammensetzung und Größe. Bei diesen Untersuchungen wurden bisher unbekannte Scheiben um die Sterne HD 72106 und HD 113766 gefunden. Beide Scheiben beinhalten Silikate in einem sehr weit fortgeschrittenen Entwicklungszustand, ähnlich jenen in Kometen unseres Sonnensystems. Wir zeigen ferner die erste Bestätigung einer großen Scheibe um epsilon Eri anhand von Daten, die mit dem Bolometer Array SIMBA am 15m Radioteleskop SEST in La Silla gewonnen wurden. Die aus früheren Beobachtungen gefolgerte innere Struktur dieser Scheibe kann alternativ aber auch durch Rauscheffekte erklärt werden."],"dc:format.medium":["application/pdf"],"dc:publisher":["Universitätsbibliothek Heidelberg"],"dc:title":["High-resolution studies of protoplanetary disks","Hochauflösende Untersuchungen protoplanetarer Scheiben"],"dc:type":["doctoralThesis"],"thesis:degree_level":["thesis.doctoral"],"thesis:institution_name":["Universität Heidelberg"]},"updated_at":"2026-07-24T02:30:04Z"}