Publications (20)
Long-term monitoring of Ark 120 with Swift
M. Gliozzi, I. E. Papadakis, D. Grupe +2
We report the results of a six-month Swift monitoring campaign of Ark120, a prototypical bare Seyfert1 galaxy. The lack of intrinsic absorption combined with the nearly contemporan…
Probing non-Gaussianities on Large Scales in WMAP5 and WMAP7 Data using Surrogates
C. Raeth, G. Rossmanith, G. Morfill +2
Probing Gaussianity represents one of the key questions in modern cosmology, because it allows to discriminate between different models of inflation. We test for large-scale non-Ga…
On the Nature of X-ray Variability in Ark 564
M. Gliozzi, W. Brinkmann, C. Raeth +3
We use data from a recent long ASCA observation of the Narrow Line Seyfert 1 Ark 564 to investigate in detail its timing properties. We show that a thorough analysis of the time se…
XMM-Newton timing mode observations of Mrk 421
W. Brinkmann, I. E. Papadakis, C. Raeth +2
We present the results of a detailed temporal analysis of the bright BL Lac object Mrk 421 using the three available long timing mode observations by the EPIC PN camera. This detec…
Non-Gaussianity as a Probe of the Physics of the Primordial Universe and the Astrophysics of the Low Redshift Universe
E. Komatsu, N. Afshordi, N. Bartolo +58
A new and powerful probe of the origin and evolution of structures in the Universe has emerged and been actively developed over the last decade. In the coming decade, non-Gaussiani…
A panchromatic view of PKS 0558-504: an ideal laboratory to study the disk-jet link
M. Gliozzi, I. E. Papadakis, D. Grupe +3
PKS 0558-504 is the brightest radio-loud Narrow-Line Seyfert 1 galaxy at X-ray energies. Here we present results from the radio, optical, UV, and X-ray bands obtained with Swift, X…
Non-Gaussian Signatures in the five-year WMAP data as identified with isotropic scaling indices
G. Rossmanith, C. Raeth, A. J. Banday +1
We continue the analysis of non-Gaussianities in the CMB by means of the scaling index method (SIM, Raeth, Schuecker & Banday 2007) by applying this method on the 5-year WMAP data.…
Spectral variability analysis of an XMM-Newton observation of Ark 564
W. Brinkmann, I. E. Papadakis, C. Raeth
We present a spectral variability analysis of the X-ray emission of the Narrow Line Seyfert 1 galaxy Ark 564 using the data from a ~100 ks XMM-Newton observation. Taking advantage…
Search for non-Gaussianities in the WMAP data with the Scaling Index Method
G. Rossmanith, H. Modest, C. Raeth +3
In the recent years, non-Gaussianity and statistical isotropy of the Cosmic Microwave Background (CMB) was investigated with various statistical measures, first and foremost by mea…
A model-independent test for scale-dependent non-Gaussianities in the CMB
C. Raeth, G. Morfill, G. Rossmanith +2
We present a model-independent method to test for scale-dependent non-Gaussianities in combination with scaling indices as test statistics. Therefore, surrogate data sets are gener…
Analysing Large Scale Structure: I. Weighted Scaling Indices and Constrained Randomisation
C. Raeth, W. Bunk, M. Huber +3
The method of constrained randomisation is applied to three-dimensional simulated galaxy distributions. With this technique we generate for a given data set surrogate data sets whi…
Scale-dependent non-Gaussianities in the WMAP data as identified by using surrogates and scaling indices
C. Raeth, A. J. Banday, G. Rossmanith +5
We present a model-independent investigation of the WMAP data with respect to scale- dependent non-Gaussianities (NGs) by employing the method of constrained randomization. For gen…
Revisiting algorithms for generating surrogate time series
C. Raeth, M. Gliozzi, I. E. Papadakis +1
The method of surrogates is one of the key concepts of nonlinear data analysis. Here, we demonstrate that commonly used algorithms for generating surrogates often fail to generate…
Characterizing black hole variability with nonlinear methods: the case of the X-ray Nova 4U 1543-47
M. Gliozzi, C. Raeth, I. E. Papadakis +1
We investigate the possible nonlinear variability properties of the black hole X-ray nova 4U1543-47 to complement the temporal studies based on linear techniques, and to search for…
A Scaling Index Analysis of the WMAP three year data: Signatures of non-Gaussianities and Asymmetries in the CMB
C. Raeth, P. Schuecker, A. J. Banday
Local scaling properties of the co-added foreground-cleaned three-year Wilkinson Microwave Anisotropy Probe (WMAP) data are estimated using weighted scaling indices. The scaling in…
Long-term monitoring of PKS0558-504 with Swift: the disc-corona link
M. Gliozzi, I. E. Papadakis, D. Grupe +2
PKS 0558-504 is a highly variable, X-ray bright, radio-loud, Narrow-Line Seyfert 1 galaxy with super-Eddington accretion rate and extended jets that do not dominate the emission be…
XMM-Newton long-look observation of the narrow line Seyfert 1 galaxy PKS0558-504; I: Spectral analysis
I. E. Papadakis, W. Brinkmann, M. Gliozzi +3
We present results from the spectral analysis of a long XMM-Newton observation of the radio-loud NLS1 galaxy PKS0558-504. The source is highly variable, on all sampled time scales.…
Analysing large scale structure: II. Testing for primordial non-Gaussianity in CMB maps using surrogates
C. Raeth, P. Schuecker
The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate alt…
Time Series with Tailored Nonlinearities
C. Raeth, I. Laut
It is demonstrated how to generate time series with tailored nonlinearities by inducing well- defined constraints on the Fourier phases. Correlations between the phase information…
Correlated spectral and temporal changes in 3C 390.3: a new link between AGN and Galactic Black Hole Binaries?
M. Gliozzi, I. E. Papadakis, C. Raeth
This work presents the results from a systematic search for evidence of temporal changes (i.e., non-stationarity) associated with spectral variations in 3C 390.3, using data from a…