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Showing 1 to 14 of 14 for “"galactic centre"”.
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High Resolution Near-Infrared Imaging Observations of the Galactic Centre
Ziel der vorliegenden Doktorarbeit war es, neue Erkenntnisse über die Struktur, Zusammensetzung und Dynamik des zentralen Sternhaufens unserer Milchstraße zu gewinnen. Im Mittelpunkt unserer Analysen stand dabei vor allem die Natur der Konzentration einiger Millionen Sonnenmassen dunkler Materie im …
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A COMPARISON OF STAR FORMATION WITHIN THE GALACTIC CENTRE AND GALACTIC DISC
… study of a sample of IRDCs within the Disc and Centre of the Milky Way; two very different environments. Several key aspects of the star formation process within IRDCs from these environments are investigated. Firstly, a chemical signpost – the deuterium fraction of N2H+ – is used to identify …
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Photon reconstruction for the H.E.S.S. 28 m telescope and analysis of Crab Nebula and galactic centre observations
… analysis is performed on the region around the Galactic Centre. The analysis results emphasise the capabilities of the new telescope to measure γ-rays in an energy range that is interesting for both theoretical and experimental astrophysics. The presented analysis features the lowest energy …
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The motion of stars and the accretion of matter in the fermion ball and black hole scenarios of the galactic centre
… SO-I, SO-2 and SO-4, in the vicinity of the galactic centre, is investigated using a X2 analysis of the parameters in our line of sight. The resulting phase spaces for the black hole and fermion ball scenarios are compared. We find that due to the lack of accurate z or Vz data, the upper …
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The red clump stars as a distance indicator : review and application
… was primarily to determine the distance to the Galactic Centre using a new technique pioneered by Paczynski and Stanek (1998) that uses the red clump stars as a standard candle. This was made possible by the large number of stars simultaneously observed by the OGLE microlensing project which …
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Exploring gravity
… from many nearby galaxies, as well as the Galactic centre. Bursts could provide insightful constraints on the MBHs' parameters. These could elucidate the formation history of the MBHs and, by association, their host galaxies. The Galactic centre is the most promising source. Its event rate …
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The nucleus of Centaurus A
… inside the central r<1.5 arcsec of the active galactic nucleus are successfully described by a (warped) gas disk, rotating in the joint gravitational potential of the stars and a black hole of Mbh~7x10^7 Msolar. With our revised Mbh estimate, that is a factor ~3 lower than previous …
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The formation of high-mass stars and stellar clusters in the extreme environment of the Central Molecular Zone
… that are studied in detail belong to the Galactic centre dust ridge -- a group of six high-mass (M ~ 10^(4-5) Msun), dense (R ~ 1-3 pc, n > 10^(4) cm^(-3)), and quiescent molecular clouds. These properties make these clouds ideal candidates for representing the earliest stages of high-mass …
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A new population of very high-energy gamma-ray sources detected with H.E.S.S. in the inner part of the Milky Way
… at an unprecedented sensitivity level. The Galactic plane between +- 30deg, in longitude and +-3deg, in latitude relative to the Galactic centre was observed for a total of 230 hours, reaching an average flux sensitivity of 3% of the Crab nebula at energies above 200 GeV. Fourteen new …
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Heavily-reddened lines of sight in the galaxy
… of 3.4 pm band enhancement towards the Galactic Centre. No global dependence on Galactic longitude is evident in the 3.4 pm band strengths towards the Stephenson stars. Profile fining of the hydrocarbon band towards these sources indicates some variation between lines of sight, but …
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Modeling the cosmological co-evolution of supermassive black holes and galaxies
… of supermassive black holes (BHs), Active Galactic Nuclei (AGN) and their hosting dark matter (DM) halos and galaxies, within the standard CDM scenario. We analyze both analytic, semi-analytic and hybrid techniques and use the most recent observational data available to constrain the …
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Fast Stars in the Milky Way
… that the hypervelocity stars originated in the Galactic centre by showing that a Large Magellanic Cloud (LMC) origin better explains their distribution on the sky. In Ch. 5 I present three ground-breaking hypervelocity results with Gaia DR2: 1) only 41 of the 524 hypervelocity star candidates …
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Simulations of Galaxy Formation and Large Scale Structure
… typically overestimated the emission from the centre of the Milky Way and from its halo's substructure. We find an overall enhancement of at most a factor of a few with respect to a smooth halo of standard NFW structure. For an observation outside the region around the galactic centre where the …