TY - JOUR A1 - Christensen, Lise Bech A1 - Schulte-Ladbeck, R. E. A1 - Sanchez, Sebastian F. A1 - Becker, Thomas A1 - Jahnke, Knud A1 - Kelz, A. A1 - Roth, Martin M. A1 - Wisotzki, Lutz T1 - Abundances and kinematics of a candidate sub-damped Lymana galaxy toward PHL 1226 N2 - The spectrum of the quasar PHL 1226 is known to have a strong Mg II and sub-damped Lymanalpha (sub-DLA) absorption line system with N(H I) = (5 +/- 2) x 10(19) cm(-2) at z = 0.1602. Using integral field spectra from the Potsdam Multi Aperture Spectrophotometer (PMAS) we investigate a galaxy at an impact parameter of 6".4 which is most probably responsible for the absorption lines. A fainter galaxy at a similar redshift and a slightly larger distance from the QSO is known to exist, but we assume that the absorption is caused by the more nearby galaxy. From optical Balmer lines we estimate an intrinsic reddening consistent with 0, and a moderate star formation rate of 0.5 M-circle dot yr(-1) is inferred from the Ha luminosity. Using nebular emission line ratios we find a solar oxygen abundance 12 + log (O/H) = 8.7 +/- 0.1 and a solar nitrogen to oxygen abundance ratio log (N/O) = -1.0 +/- 0.2. This abundance is larger than those of all known sub-DLA systems derived from analyses of metal absorption lines in quasar spectra. On the other hand, the properties are compatible with the most metal rich galaxies responsible for strong Mg II absorption systems. These two categories can be reconciled if we assume an abundance gradient similar to local galaxies. Under that assumption we predict abundances 12 + log (O/H) = 7.1 and log (N/O) = -1.9 for the sub-DLA cloud, which is similar to high redshift DLA and sub-DLA systems. We find evidence for a rotational velocity of similar to200 km s(-1) over a length of similar to7 kpc. From the geometry and kinematics of the galaxy we estimate that the absorbing cloud does not belong to a rotating disk, but could originate in a rotating halo Y1 - 2005 ER - TY - JOUR A1 - Christensen, Lise Bech A1 - Sanchez, Sebastian F. A1 - Jahnke, Knud A1 - Becker, Thomas A1 - Kelz, A. A1 - Wisotzki, Lutz A1 - Roth, Martin M. T1 - Integral field observations of damped Lyman-alpha galaxies N2 - We report preliminary results from a targeted investigation on quasars containing damped Lyman-alpha absorption (DLA) lines as well strong metal absorption lines, carried out with the Potsdam Multi Aperture Spectrophotometer (PMAS). We search for line-emitting objects at the same redshift as the absorption lines and close to the line of sight of the QSOs. We have observed and detected the already confirmed absorbing galaxies in Q2233+131 (Z(abs) = 3.15) and Q0151+045 (Z(abs),= 0.168), while failing to find spectral signatures for the z = 0.091 absorber in Q0738+313. From the Q2233+131 DLA galaxy, we have detected extended Lyalpha emission from an area of 3" x 5" Y1 - 2004 ER - TY - JOUR A1 - Wisotzki, Lutz A1 - Becker, Thomas A1 - Christensen, Lise Bech A1 - Jahnke, Knud A1 - Helms, Andreas A1 - Kelz, A. A1 - Roth, Martin M. A1 - Sanchez, Sebastian F. T1 - Integral field spectrophotometry of gravitationally lensed QSOs with PMAS N2 - We present spatially resolved spectrophotometric observations of multiply imaged QSOs, using the Potsdam Multi- Aperture Spectrophotometer (PMAS), with the intention to search for spectral differences between components indicative of either microlensing or dust extinction. For the quadruple QSO HE 0435-1223 we find that the continuum shapes are indistinguishable, therefore differential extinction is negligible. The equivalent widths of the broad emission lines are however significantly different, and we argue that this is most likely due to microlensing. Contrariwise, the two components of the well-known object UM 673 have virtually identical emission line properties, but the continuum slopes differ significantly and indicate different dust extinction along both lines of sight Y1 - 2004 SN - 0004-6337 ER - TY - JOUR A1 - Christensen, Lise Bech A1 - Sanchez, Sebastian F. A1 - Jahnke, Knud A1 - Becker, Thomas A1 - Wisotzki, Lutz A1 - Kelz, A. A1 - Popovic, L. C. A1 - Roth, Martin M. T1 - Integral field spectroscopy of extended Ly alpha emission from the DLA galaxy in Q2233+131 N2 - This paper presents observations of an extended Lyman-alpha emission nebula surrounding the galaxy responsible for the Damped Lyman-alpha Absorption (DLA) line in the spectrum of the quasar Q2233+131. With the Potsdam Multi Aperture Spectrophotometer (PMAS) we measure the properties of the extended Lyalpha emission in an area of 3" x 5" having a total line flux of (2.8 +/- 0.3) x 10(-16) erg cm(-2) s(-1), which at redshift z = 3.15 corresponds to a luminosity of (2.4(-0.2)(+0.3)) x 10(43) erg s(-1) and a size of 23 x 38 kpc. The location of the emission is spatially coincident with the previously detected DLA galaxy, but extends significantly beyond its limb. We argue that the Lya emission is likely to be caused by an outflow from the DLA galaxy, presumably powered by star formation. In the case of negligible dust extinction, the Lya luminosity indicates a star-formation rate of 19 +/- 10 M-. yr(-1) consistent with that derived from the UV continuum flux from the parent galaxy. The wind velocity indicated by the integral field spectra is of the order of several hundred km s(-1). We find no indication of emission originating in a rotating disk Y1 - 2004 ER - TY - JOUR A1 - Jahnke, Knud A1 - Wisotzki, Lutz A1 - Sanchez, Sebastian F. A1 - Christensen, Lise Bech A1 - Becker, Thomas A1 - Kelz, A. A1 - Roth, Martin M. T1 - Integral field spectroscopy of QSO host galaxies N2 - We describe a project to study the state of the ISM in similar to20 low redshift (z < 0.3) QSO host galaxies observed with the PMAS integral field spectrograph. We describe the development of the method to access the stellar and gas components of the spectrum without the strong nuclear emission, in order to access the host galaxy properties in the central region. It shows that integral field spectroscopy promises to be very efficient in studying the gas distribution and its velocity field, and also the spatially resolved stellar population in the host galaxies of luminous AGN Y1 - 2004 ER - TY - JOUR A1 - Christensen, Lise Bech A1 - Becker, Thomas A1 - Jahnke, Knud A1 - Kelz, A. A1 - Roth, Martin M. A1 - Sanchez, S. S. A1 - Wisotzki, Lutz T1 - Integral field spectroscopy of SN 2002er with PMAS N2 - sent observations of the Type Ia supernova SN 2002er during the brightening phase. The observations were performed with the Potsdam Multi Aperture Spectrophotometer (PMAS) integral field instrument. Due to the 8arcsecx8 arcsec field of view of the spectrograph an accurate background subtraction was possible. Results from analyses of the evolution of absorption features in comparisons with other SNe show that SN 2002er is a fairly bright Type Ia supernova with a peak brightness of MB=-19.6+/-0.1. Y1 - 2003 ER - TY - JOUR A1 - Wisotzki, Lutz A1 - Becker, Thomas A1 - Christensen, Lise Bech A1 - Helms, Andreas A1 - Jahnke, Knud A1 - Kelz, A. A1 - Roth, Martin M. A1 - Sanchez, Sebastian F. T1 - Integral-field spectrophotometry of the quadruple QSO HE 0435-1223 : Evidence for microlensing N2 - We present the first spatially resolved spectroscopic observations of the recently discovered quadruple QSO and gravitational lens HE 0435-1223. Using the Potsdam Multi-Aperture Spectrophotometer (PMAS), we show that all four QSO components have very similar but not identical spectra. In particular, the spectral slopes of components A, B, and D are indistinguishable, implying that extinction due to dust plays no major role in the lensing galaxy. While also the emission line profiles are identical within the error bars, as expected from lensing, the equivalent widths show significant differences between components. Most likely, microlensing is responsible for this phenomenon. This is also consistent with the fact that component D, which shows the highest relative continuum level, has brightened by 0.07 mag since Dec. 2001. We find that the emission line flux ratios between the components are in better agreement with simple lens models than broad band or continuum measurements, but that the discrepancies between model and data are still unacceptably large. Finally, we present a detection of the lensing galaxy, although this is close to the limits of the data. Comparing with a model galaxy spectrum, we obtain a redshift estimate of zlens=0.44+/- 0.02. Y1 - 2003 ER - TY - THES A1 - Christensen, Lise Bech T1 - Probing quasar sight lines in three dimensions T1 - Untersuchung von Quasar-Sichtlinien in drei Dimensionen N2 - Strong damped Lyman alpha absorption (DLA) lines seen spectra of distant quasar are believed to arise when the sight line to the quasar goes trough the disc of a galaxy or a proto galaxy. Most of the neutral matter in the universe is contained in these clouds of neutral hydrogen that cause the absorption lines. Hence these DLAs are reservoirs for the formation of stars and galaxies throughout the universe. Despite intensive efforts over more than two decades only few galaxies responsible for the DLAs have been found. The problem is that the galaxies that harbour the neutral clouds are not necessarily bright, and selecting galaxies based on absorption lines could well select different types of galaxies than found in large surveys. If we are to understand how galaxies form out of neutral gas clouds it is essential to locate the galaxies in which DLAs reside. This thesis explores the use of integral field spectroscopy (IFS) to observe quasars known to have strong absorption lines in their spectra. IFS allows us to obtain a spectrum at many spatial points close to the quasar, thus providing images and spectroscopy simultaneously. From the imaging part, we can directly identify objects, and from the spectroscopy we can calculate the distances to the objects. When the distance of the object found in emission matches the distance to the object that cause the DLA line, we have identified the absorbing galaxy. Using this technique, we have showed that we can successfully recover a few DLA galaxies known previously from the literature. In a survey aimed to increase the number of DLA galaxies we have identified eight new candidate DLA galaxies. The projected distances from the candidates to the quasar sight lines indicate that the DLA galaxies have sizes similar to local disc galaxies. Hence our results suggest that large discs may be present when the universe was just 2 billion years old. We furthermore find no differences between the sizes of the very distant DLA galaxies and those that are not so distant. The large sizes imply that their neutral hydrogen masses are also similar to those in local galaxies, but we argue that the DLA galaxies are not necessarily as luminous as the present day disc galaxies. Taking advantage of the three-dimensional view provided by the IFS data, the second part of this thesis investigates extended emission line regions arising in the quasar neighborhood. We find that extended emission line nebulae are common around quasars, and explore the effects that may be the cause. Some quasars are known to be powerful radio emitters while others are not detected at radio wavelengths. We find that significantly larger and brighter emission line nebulae are found around the quasars which have the brightest radio emission, and in particular those that have large radio jets. The existence of the nebulae can be interpreted as an interaction of the radio jet with the surrounding medium, but we can not rule out a scenario where there are density or temperature differences in the surrounding environment. Only for the brightest object, where additional velocity information can be derived from the IFS data, can we argue for an interaction. In conclusion the use of IFS to search for faint emission lines, both from point sources and extended nebulae provides exciting new results within the scientific areas studied here. N2 - Man glaubt, daß starke gedämpfte Lyman alpha Absorptionslinien (damped Lyman alpha lines, DLA lines) in den Spektren entfernter Quasare entstehen, wenn die Sichtlinie zu dem Quasar durch eine Galaxie oder eine Proto-Galaxie geht. Die meiste neutrale Materie des Universums ist in diesen Wolken aus neutralem Wasserstoff enthalten, die die Absorptionslinien verursachen. Daher sind diese DLAs Reservoire für die Bildung von Sternen und Galaxien im gesamten Universum. Trotz intensiver Anstrengungen seit mehr als zwei Jahrzehnten konnten nur wenige Galaxien gefunden werden, die für DLAs verantwortlich sind. Das Problem ist, daß die Galaxien, die die neutralen Wolken beherbergen, nicht notwendigerweise hell sind, und Galaxien basierend auf Absorptionslinien zu selektieren, könnte leicht andere Typen von Galaxien selektieren, als diejenigen, die in großen Durchmusterungen gefunden werden. Wenn wir verstehen wollen wie Galaxien aus neutralen Gaswolken entstehen, ist es entscheidend, die Galaxien ausfindig zu machen, in denen DLAs liegen. Diese Doktorarbeit erforscht die Nutzung der Ganzfeldspektroskopie (integral field spectroscopy, IFS), um Quasare zu beobachten, die bekanntermaßen starke Absorptionslinien in ihren Spektren haben. IFS erlaubt uns, ein Spektrum an vielen räumlichen Punkten nahe des Quasars zu erhalten, somit Bilder und Spekroskopie gleichzeitig zu liefern. Aus den Bildern können wir direkt Objekte identifizieren und aus der Spektroskopie können wir die Entfernungen zu den Objekten berechnen. Wenn die Entfernung zum gefundenen Objekt mit der Entfernung zu einer DLA-Linie übereinstimmt, dann haben wir die absorbierende Galaxie gefunden. Diese Methode anwendend, können wir zeigen, daß wir erfolgreich einige wenige schon aus der Literatur bekannte DLA-Galaxien wiederentdecken können. In einer auf Erhöhung der Zahl von DLA-Galaxien abzielenden Duchmusterung haben wir acht neue DLA-Galaxienkandidaten identifiziert. Die projizierten Entfernungen von den Kandidaten zu den Quasarsichtlinien lassen erkennen, daß die DLA-Galaxien ähnliche Größen haben, wie nahe Scheibengalaxien. Daher lassen unsere Resultate darauf schließen, daß es große Scheibengalaxien gegeben haben könnte, als das Universum gerade zwei Milliarden Jahre alt war. Außerdem finden wir keine Unterschiede zwischen den Größen der sehr weit entfernten DLA-Galaxien und jenen, die nicht so weit entfernt sind. Die Größen implizieren, daß ihre Massen gebunden in neutralem Wasserstoff auch ähnlich sind zu jenen in lokalen Galaxien, aber wir vertreten die Ansicht, daß DLA-Galaxien nicht notwendigerweise so leuchtkräftig sind wie heutige Scheibengalaxien. Den dreidimensionalen Blick ermöglicht durch die IFS-Daten ausnutzend, untersucht der zweite Teil dieser Doktorarbeit ausgedehnte Emissionslinienregionen, die in der Nachbarschaft der Quasare entstehen. Wir finden heraus, daß ausgedehnte Emissionsliniennebel um Quasare häufig sind und erforschen die ihnen zugrundeliegenden Effekte. Einige Quasare sind bekannte starke Radioquellen, während andere nicht im Radiobereich entdeckt werden. Wir zeigen, daß bedeutend größere und hellere Emissionsliniennebel um Quasare gefunden werden, welche die stärkste Radioemission, insbesondere große Radiojets, aufweisen. Die Existenz der Nebel kann interpretiert werden als eine Wechselwirkung der Radiojets mit dem umgebenden Medium, aber wir können nicht ausschließen, daß es Dichte- oder Temperaturunterschiede in der Umgebung gibt. Nur für die hellsten Objekte, für die zusätzliche Geschwindigkeitsinformation aus den IFS-Daten abgeleitet werden kann, vertreten wir die Ansicht der Wechselwirkung. Die Nutzung der IFS bei der Suche nach schwachen Emissionslinien von Punktquellen wie auch ausgedehnten Nebeln bietet spannende neue Ergebnisse in den hier studierten wissenschaftlichen Gebieten. KW - Emissionslinien-Galaxie KW - Aktive Galaxie KW - Damped Lyman alpha Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-5844 ER -