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Development of Realistic Simulations of the Interactions Between Stars and the Interstellar Medium in Disk GalaxiesZeltwanger, Thomas January 2000 (has links) (PDF)
No description available.
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Optical polarimetry studies of Seyfert galaxiesFelton, Michelle Ann January 1999 (has links)
Optical imaging polarimetry has been performed on seven nearby Seyfert galaxies, three with face-on and four with edge-on host galaxies of various morphological classifications. Observations in V, R, B and H(_a) wavebands are presented as maps of total intensity and of polarized intensity, overlaid with polarization vectors. Independent determinations of the interstellar polarization (ISP) contribution from our own galaxy are made where possible, and are used to produce ISP corrected maps. The polarization patterns seen in the maps show evidence of either dichroic extinction, which indicates the presence of non-spherical dust grains in large-scale galactic magnetic fields, or scattering, which is due to the illumination of regions of dust grains or electrons. The polarization features, which are observed at the different wavebands, are then compared to recent models of polarization in external galaxies. Estimates of the intrinsic Seyfert nuclear polarization are made where possible by correcting for ISP and for an approximation of the dilution due to the host galaxy flux by using values from previous studies. Both the measured and the corrected nuclear polarizations are compared with previously published values, and are discussed in the context of the standard models of Seyfert galaxies. Most of the observed galaxies show evidence of polarization, both from the host galaxy and from the intrinsic Seyfert nucleus. In particular, distinct polarization features: bands of polarization consistent with extended dusty disks aligned with the dusty tori proposed in Seyferts, and regions of polarization corresponding to scattering of the nuclear continuum along the biconical extended Seyfert emission-line regions, have been identified in several of the observed galaxies.
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Dust penetrated quantitative classifcation of nearby barred spiral galaxiesTailor, Asha 12 September 2012 (has links)
The objective of this dissertation is twofold. Firstly an extensive yet concise literature
review on the state-of-the-art of near infrared barred spiral galaxy classi cation is presented.
Secondly, two quantitative approaches to galaxy classi cation at near infrared
wavelengths, the relative gravitational torque method and the isophotal ellipse tting
method, are applied for the rst time to a sample of selected Spitzer IRAC nearby
barred galaxies. Maximum relative gravitational torques are derived for a sample of 40
nearby bright barred disk galaxies at 3.6 m and 4.5 m. These torques are compared
between galaxy pairs at these passbands and we nd an excellent agreement between
the 3.6 m and 4.5 m morphology. The sample used incorporates a wide range of
inclination and bar strength values. The tight coupling of 3.6 m and 4.5 m morphology
provides an opportunity to classify intermediate redshift galaxies that have their
near-infrared rest frame emissions shifted red-ward to 4.5 m; i.e.: out to z = 0:25.
We nd a greater frequency of higher maximum relative torques in our sample compared
with either Block et al. (2002) or Buta et al. (2004) due to sample bias, as
this dissertation is aimed at understanding quantitative methods in classifying barred
galaxies. Furthermore, we compare results from applying an isophotal ellipse tting
technique and a gravitational torque analysis to a common sample of 28 nearby barred
S4G/Spitzer galaxies imaged at 3.6 m. These two quantitative bar strength methods
are applied to images that have identical orientation and deprojection parameters
for an objective comparison. We nd a strong correlation between the gravitational
torque and isophotal ellipse tting methods which in principle supports a method for
estimating bar potentials out to intermediate redshifts by using an isophotal ellipse tting
approach. This has important implications for bar-fraction estimates and galaxy
accretion/evolution scenarios.
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Etude de la réaction de cassure du (^11)Be sur cible de (^48)Ti ; le towing mode, un outil spectroscopique pour l'étude des noyaux.Lima, Victor 07 October 2004 (has links) (PDF)
Dans cette thèse nous avons éffectué l'analyse des données relatives à l'expérience réalisée au GANIL pour laquelle un faisceau de (^11)Be a bombardé une cible de (^48)Ti dans le but d'étudier la réaction (^48]Ti((^11)Be,(^10)Be+n+gamma) à 41 MeV/nucléon. L'utilisation du towing mode dans l'étude des noyaux a montré sa potentialité pour la détermination de facteurs spectroscopiques à l'aide du calcul TDSE. De nouveaux développements devraient nous permettre d'approfondir nos connaissances sur les noyaux exotiques avec, dans un avenir proche, le projet SPIRAL II extension du projet SPIRAL au GANIL. Ce projet fournira des faisceaux radioactifs plus lourds que ceux étudiés actuellement grâce à la fission de noyau d'uranium induite par un faisceau de deutons de très haute intensité.
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Broadband counterwound spiral antenna for subsurface radar applications /Lim, Teck Yong. January 2003 (has links) (PDF)
Thesis (M.S. in Engineering Science (Electrical Engineering))--Naval Postgraduate School, December 2003. / Thesis advisor(s): David Jenn, Jeffrey B. Knorr. Includes bibliographical references (p. 73-76). Also available online.
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On the spiral troughs of MarsSmith, Isaac Blaine 08 November 2013 (has links)
The north and south polar layered deposits (NPLD and SPLD respectively) of Mars are 2 – 3 km thick and mostly ice, comprising nearly all of the known water reserves on Mars. They are commonly believed to hold a detailed record of recent (~10 – 100 Myr) climate within their layers. Dominating the surface of the NPLD, intriguing spiral depressions called troughs, exhibit a pinwheel appearance.
In late 2006, the Shallow Radar (SHARAD) instrument began making observations. SHARAD can detect internal structure within the PLD, making observations that are impossible with instruments that only inspect the surface. SHARAD data reveals a unique stratigraphic record associated with trough formation and migration. The troughs did not exist during deposition of the first half of NPLD accumulation but initiated some 1000 m below the current surface and have migrated as much as 100 km northward. Three processes are responsible for this migration: wind transport, insolation induced sublimation, and atmospheric deposition.
I synthesize work from ground penetrating radar, optical imagery, established analogs, and atmospheric modeling in order to derive a process model that describes trough formation and evolution, including migration. The NPLD spiral troughs belong to a larger classification of features called cyclic steps, which can exist in either erosional or depositional environments. On the SPLD, troughs and a variety of other features exist. While SPLD features are more complex than NPLD troughs, they exist due to the same three processes. / text
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Na^+ Channel Blockade Causes a Prolongation of Electrical Diastole during Spiral-type Reentry in the VentricleNIHEI, Motoki, YAMAMOTO, Mitsuru, NIWA, Ryoko, ARAFUNE, Tatsuhiko, MISHIMA, Akira, SHIBATA, Nitaro, SAKUMA, Ichiro, INADA, Hiroshi, HONJO, Haruo, KAMIYA, Kaichiro, KODAMA, Itsuo 12 1900 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
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The globular cluster system of the Sombrero galaxyVanDalfsen, Marcel L. Harris, W. E. January 2004 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: W.E. Harris. Includes bibliographical references (p. 127-132).
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Dark and luminous matter in bright spiral galaxiesKassin, Susan Alice Joan, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiv, 86 p.; also includes graphics. Includes bibliographical references (p. 83-86).
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Funktionsdiagnostik des Herzens mittels 4-Schicht-Mehrzeilen-ComputertomographieTrebar, Branko, January 2005 (has links)
Tübingen, Univ., Diss., 2005.
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