129 citations · 884 across the 36 of their papers we have counts for
39 papers
Gas and stellar dynamics in Stephan's Quintet: Mapping the kinematics in a closely interacting compact galaxy group
M. Yttergren, P. Misquitta, Á. Sánchez-Monge +4
Stephan's Quintet (SQ) is a nearby compact galaxy group and a perfect laboratory for studying the process of galaxy evolution through galaxy harassment and interaction. By analysin…
Kinematic Structure of the Galactic Center S-cluster
Basel Ali, Daria Paul, Andreas Eckart +7
We present a detailed analysis of the kinematics of 112 stars that mostly comprise the high velocity S-cluster and orbit the super massive black hole SgrA* at the center of the Mil…
Interactions among intermediate redshift galaxies. The case of SDSSJ134420.86+663717.8
Persis Misquitta, Micah Bowles, Andreas Eckart +4
We present the properties of the central supermassive black holes and the host galaxies of the interacting object SDSSJ134420.86+663717.8. We obtained optical long slit spectroscop…
Monitoring dusty sources in the vicinity of Sgr A*
F. Peißker, S. E. Hosseini, M. Zajacek +5
We trace several dusty infrared sources on their orbit around the supermassive black hole (SMBH) SgrA* in the center of our galaxy. We give an overview of known and unknown sources…
Radio spectral index distribution of SDSS-FIRST sources across optical diagnostic diagrams
Michal Zajaček, Gerold Busch, Mónica Valencia-S. +7
A detailed understanding of how the activity of a galactic nucleus regulates the growth of its host is still missing. To understand the activity and the types of accretion of super…
Bow shock sources close to the Galactic centre
Michal Zajacek, Andreas Eckart, Seyedeh Elaheh Hosseini
We provide an up-to-date summary of the current observational and theoretical studies of stellar bow-shock sources close to the Galactic centre. The symmetry axis of a bow shock pr…
Super-Massive Black Hole mass estimation from bright flares
Vladimir Karas, Michal Bursa, Michal Dovciak +4
Super-Massive Black Holes reside in galactic nuclei, where they exhibit episodic bright flares due to accretion events. Taking into account relativistic effects, namely, the boosti…
Near-infrared observations of star formation and gas flows in the NUGA galaxy NGC 1365
Nastaran Fazeli, Gerold Busch, Monica Valencia-S. +4
In the framework of understanding the gas and stellar kinematics and their relations to AGNs and galaxy evolution scenarios, we present spatially resolved distributions and kinemat…
Light and shadow in the Galactic Center - On the detection of the relativistic periastron shift of star S2 in the Galactic Center
A. Eckart, M. Parsa, E. Mossoux +11
We report on the nature of prominent sources of light and shadow in the Galactic Center. With respect to the Bremsstrahlung X-ray emission of the hot plasma in that region the Gala…
The Multifrequency Behavior of Sagittarius A*
A. Eckart, M. Zajacek, M. Parsa +15
The Galactic Center is the closest galactic nucleus that allows us to determine the multi-frequency behavior of the supermassive black hole counterpart Sagittarius A* in great deta…
Bright X-ray flares from Sgr A*
G. D. Karssen, M. Bursa, A. Eckart +4
We address a question whether the observed light curves of X-ray flares originating deep in galactic cores can give us independent constraints on the mass of the central supermassi…
Nuclear Activity and the Conditions of Star-formation at the Galactic Center
A. Eckart, M. Valencia-S., B. Shahzamanian +15
The Galactic Center is the closest galactic nucleus that can be studied with unprecedented angular resolution and sensitivity. We summarize recent basic observational results on Sa…
A low-luminosity type-1 QSO sample: IV. Molecular gas contents and conditions of star formation in three nearby Seyfert galaxies
Lydia Moser, Melanie Krips, Gerold Busch +8
We present a pilot study of ~ 3" resolution observations of low CO transitions with the Submillimeter Array in three nearby Seyfert galaxies, which are part of the low-luminosity q…
The Milky Way's Supermassive Black Hole: How good a case is it? A Challenge for Astrophysics & Philosophy of Science
Andreas Eckart, Andreas Huettemann, Claus Kiefer +7
The compact and, with 4.3+-0.3 million solar masses, very massive object located at the center of the Milky Way is currently the very best candidate for a supermassive black hole (…
Star formation and gas flows in the centre of the NUGA galaxy NGC 1808 observed with SINFONI
Gerold Busch, Andreas Eckart, Mónica Valencia-S. +4
NGC 1808 is a nearby barred spiral galaxy which hosts young stellar clusters in a patchy circumnuclear ring with a radius of . In order to study the gaseous…
Polarized near-infrared light of the Dusty S-cluster Object (DSO/G2) at the Galactic Center
B. Shahzamanian, A. Eckart, M. Zajacek +6
We investigate an infrared-excess source called G2 or Dusty S-cluster Object (DSO) moving on a highly eccentric orbit around the Galaxy's central black hole, Sgr A*. We use, for th…
A low-luminosity type-1 QSO sample. V. Overluminous host spheroids and their excitation mechanisms
Gerold Busch, Nastaran Fazeli, Andreas Eckart +6
We present near-infrared (NIR) -band longslit spectra of eleven galaxies which are obtained with SOFI at the NTT (ESO). The galaxies are chosen from the low-luminosity type-1…
Line and Continuum Variability in Active Galaxies
Y. E. Rashed, A. Eckart, M. Valencia-S. +5
We compared optical spectroscopic and photometric data for 18 AGN galaxies over 2 to 3 epochs, with time intervals of typically 5 to 10 years. We used the Multi-Object Double Spect…
The Galactic Center Black Hole Laboratory
A. Eckart, S. Britzen, M. Valencia-S. +8
The super-massive 4 million solar mass black hole Sagittarius~A* (SgrA*) shows flare emission from the millimeter to the X-ray domain. A detailed analysis of the infrared light cur…
A low-luminosity type-1 QSO sample: II. Tracing circumnuclear star formation in HE 1029-1831 with SINFONI
Gerold Busch, Semir Smajić, Julia Scharwächter +6
Circumnuclear star formation and AGN feedback is believed to play a critical role in the context of galaxy evolution. The low-luminosity QSO (LLQSO) sample that contains 99 of the…
Monitoring the Dusty S-Cluster Object (DSO/G2) on its Orbit towards the Galactic Center Black Hole
M. Valencia-S., A. Eckart, M. Zajacek +23
We analyse and report in detail new near-infrared (1.45 - 2.45 microns) observations of the Dusty S-cluster Object (DSO/G2) during its approach to the black hole at the center of t…
ALMA backed NIR high resolution integral field spectroscopy of the NUGA galaxy NGC 1433
Semir Smajic, Lydia Moser, Andreas Eckart +7
We present the results of near-infrared (NIR) H- and K-band European Southern Observatory SINFONI integral field spectroscopy (IFS) of the Seyfert 2 galaxy NGC 1433. We present emi…
The infrared K-band identification of the DSO/G2 source from VLT and Keck data
Andreas Eckart, M. Horrobin, S. Britzen +24
A fast moving infrared excess source (G2) which is widely interpreted as a core-less gas and dust cloud approaches Sagittarius A* (SgrA*) on a presumably elliptical orbit. VLT K_s-…
The Galactic Center as a Paradigm for Low Luminosity Nuclei? The K-band identification of the DSO/G2 source from VLT and Keck data
Andreas Eckart, S. Britzen, M. Horrobin +27
The super-massive 4 million solar mass black hole (SMBH) SgrA* shows flare emission from the millimeter to the X-ray domain. The nucleus of the Milky Way has properties (stellar cl…