Sebastian Heinz
A5016535051- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Radio Astronomy Observations and Technology
- Astronomical Observations and Instrumentation
- Solar and Space Plasma Dynamics
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Particle Detector Development and Performance
- Astro and Planetary Science
- Geophysics and Gravity Measurements
- Scientific Research and Discoveries
- Gas Dynamics and Kinetic Theory
- Magnetic confinement fusion research
- Black Holes and Theoretical Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Relativity and Gravitational Theory
- Nuclear Physics and Applications
- Optimization and Variational Analysis
- Fluid Dynamics and Turbulent Flows
University of Wisconsin–Madison
2015-2024
SRI International
2024
Madison Group (United States)
2022
Weierstrass Institute for Applied Analysis and Stochastics
2009-2016
Friedrich-Alexander-Universität Erlangen-Nürnberg
2008-2013
Chemnitz University of Technology
2012
Queen's University Belfast
2010
Max Planck Institute for Astrophysics
2002-2010
University of Wisconsin System
2008-2010
University of Tübingen
2010
We examine the disc--jet connection in stellar mass and supermassive black holes by investigating properties of their compact emission X-ray radio bands. compile a sample ~100 active galactic nuclei with measured mass, 5 GHz core emission, 2-10 keV luminosity, together 8 total ~50 simultaneous observations Using this sample, we study correlations between (L_{R}) (L_{X}) luminosity hole (M). find that is correlated {\em both} M L_{X}, at highly significant level. In particular, show sources...
The very large collection area of ground-based gamma-ray telescopes gives them a substantial advantage over balloon or satellite based instruments in the detection very-high-energy (>600 GeV) cosmic-ray electrons. Here we present electron spectrum derived from data taken with High Energy Stereoscopic System (H.E.S.S.) imaging atmospheric Cherenkov telescopes. In this measurement, first type, are able to extend measurement beyond range accessible direct measurements. We find evidence for...
The measurement of an excess in the cosmic-ray electron spectrum between 300 and 800 GeV by ATIC experiment has - together with PAMELA detection a rise positron fraction up to 100 motivated many interpretations terms dark matter scenarios; alternative explanations assume nearby source like pulsar or supernova remnant. Here we present H.E.S.S. starting at 340 GeV. While overall flux measured is consistent data within statistical systematic errors, exclude pronounced peak as suggested for...
This White Paper, submitted to the recent ESA call for science themes define its future large missions, advocates need a transformational leap in our understanding of two key questions astrophysics: 1) How does ordinary matter assemble into scale structures that we see today? 2) do black holes grow and shape Universe? Hot gas clusters, groups intergalactic medium dominates baryonic content local Universe. To understand astrophysical processes responsible formation assembly these structures,...
We present a comprehensive synthesis model for the active galactic nuclei (AGN) evolution and growth of supermassive black hole (SMBH) in Universe. assume that holes accrete just three distinct physical states, or 'modes': at low Eddington ratio, only radiatively inefficient, kinetically dominated mode is allowed [low kinetic (LK)]; high instead, AGN may display both purely radiative [radio quiet, (HR)] loud, (HK)] mode. solve continuity equation mass function using locally determined one as...
A search for a very-high-energy (VHE; ≥100 GeV) γ-ray signal from self-annihilating particle dark matter (DM) is performed towards region of projected distance r∼45-150 pc the Galactic center. The background-subtracted spectrum measured with High Energy Stereoscopic System (H.E.S.S.) instrument in energy range between 300 GeV and 30 TeV shows no hint residual flux. Assuming conventional Navarro-Frenk-White Einasto density profiles, limits are derived on velocity-weighted annihilation cross...
Gamma-ray line signatures can be expected in the very-high-energy (${E}_{\ensuremath{\gamma}}>100\text{ }\text{ }\mathrm{GeV}$) domain due to self-annihilation or decay of dark matter (DM) particles space. Such a signal would readily distinguishable from astrophysical $\ensuremath{\gamma}$-ray sources that most cases produce continuous spectra span over several orders magnitude energy. Using data collected with H.E.S.S. instrument, upper limits on linelike emission are obtained energy range...
We report the discovery of unusually bright long-duration gamma-ray burst (GRB), GRB 221009A, as observed by Neil Gehrels Swift Observatory (Swift), Monitor All-sky X-ray Image (MAXI), and Neutron Star Interior Composition Explorer Mission (NICER). This energetic was located relatively nearby (z = 0.151), allowing for sustained observations afterglow. The large luminosity low Galactic latitude (b 4.3 degrees) make 221009A a powerful probe dust in Milky Way. Using echo tomography we map...
We derive the non-linear relation between core flux Fν of accretion-powered jets at a given frequency and mass M central compact object. For scale-invariant jet models, mathematical structure equations describing synchrotron emission from enables us to cancel out model-dependent complications dynamics, retaining only simple, model-independent algebraic M. This approach allows Fν–M for any accretion disc scenario that provides set input boundary conditions magnetic field relativistic particle...
We present the first results from a 500 ks Chandra ACIS-I observation of M87. At soft energies (0.5-1.0 keV), we detect filamentary structures associated with eastern and southwestern X-ray radio arms. Many filaments are spatially resolved widths ~300 pc. This structure is particularly striking in arm, where suggest outer edges series plasma-filled, buoyant bubbles whose ages differ by ~6 × 106 yr. These may be influenced magnetic filamentation. hard (3.5-7.5 nearly circular ring radius 2.8'...
We combined deep Chandra, ROSAT HRI, and XMM-Newton observations of M87 to study the impact active galactic nucleus (AGN) outbursts on its gaseous atmosphere. Many X-ray features appear be a direct result repetitive AGN outbursts. In particular, cavities around jet counterjet are likely due expansion radio plasma, while rings enhanced emission at 14 17 kpc probably shock fronts associated with that began 1-2 × 107 yr ago. The effects these shocks also seen in brightenings within prominent...
We report the discovery of faint very high energy (VHE; E > 100 GeV) γ-ray emission from radio galaxy Centaurus A in observations performed with High Energy Stereoscopic System (H.E.S.S.) experiment, an imaging atmospheric Cherenkov telescope array consisting four telescopes located Namibia. has been observed for more than 120 hr. signal a statistical significance 5.0σ is detected region including core and inner kpc jets. The integral flux above threshold ∼250 GeV measured to be 0.8% Crab...
Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants which are thought to accelerate energetic cosmic rays up energies ~ 10^15 eV. We report detection gamma -- tracers such from starburst galaxy NGC 253 using H.E.S.S. array imaging atmospheric Cherenkov telescopes. The gamma-ray flux above 220 GeV is F = (5.5 +/- 1.0stat 2.8sys) x 10^-13 ph. s-1 cm-2, implying cosmic-ray density about three orders magnitude larger than that center Milky Way....
Deep observations with the Very Large Array of A0620-00, performed in 2005 August, resulted first detection radio emission from a black hole binary at X-ray luminosities as low 10^{-8.5} times Eddington limit. The measured flux density, 51 \pm 7 microJy 8.5 GHz, is lowest reported for an system so far, and interpreted terms partially self-absorbed synchrotron outflowing plasma. Making use estimated outer accretion rate A0620-00 quiescence, we demonstrate that outflow kinetic power must be...
We have studied the relationship among nuclear radio and X-ray power, Bondi rate kinetic luminosity of sub-Eddington active galactic nucleus (AGN) jets, as estimated from pdV work done to inflate cavities bubbles observed in hot X-ray-emitting atmospheres their host galaxies clusters. Besides recently discovered correlation between jet we show that a clear exists also Eddington-scaled power bolometric luminosity, given by log(Lkin/LEdd) = (0.49 ± 0.07) log(Lbol/LEdd) − (0.78 0.36). The...
The extragalactic background light (EBL) is the diffuse radiation with second highest energy density in Universe after cosmic microwave background. aim of this study measurement imprint EBL opacity to γ-rays on spectra brightest sources detected High Energy Stereoscopic System (H.E.S.S.). originality method lies joint fit optical depth and intrinsic sources, assuming smoothness. Analysis a total ~105γ-ray events enables detection an signature at 8.8σ level constitutes first using very-high...
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 − 6) × 109 M☉) provides a unique opportunity to investigate the origin of high energy (VHE; E > 100 GeV) γ-ray emission generated in relativistic outflows surroundings supermassive holes. has been established as VHE emitter since 2006. displays strong variability on timescales short day. In this paper, results from joint monitoring campaign by MAGIC VERITAS instruments 2010 are reported....
We report on the first simultaneous observations that cover optical, X-ray, and high-energy gamma-ray bands of BL Lac object PKS 2155−304. The were observed for 11 days, between 2008 August 25 September 6 (MJD 54704−54715), jointly with Fermi Gamma-ray Space Telescope HESS atmospheric Cherenkov array, providing MeV–TeV spectral energy distribution (SED) new generation γ-ray telescopes. ATOM telescope RXTE Swift observatories provided optical X-ray coverage low-energy component over same time...
We present an intensive radio and X-ray monitoring campaign on the 2009 outburst of Galactic black hole candidate binary H1743-322. With high angular resolution Very Long Baseline Array, we resolve jet ejection event measure proper motions ejecta relative to position compact core jets detected at beginning outburst. This allows us accurately couple moment when occurred with spectral timing signatures. find that signatures are best diagnostic in this outburst, which as variability began...
Abstract Black hole (BH) X-ray binaries (XRBs) are ideal targets to study the connection between accretion inflow and jet outflow. Here we present quasi-simultaneous, multiwavelength observations of Galactic BH system MAXI J1820+070, throughout its 2018–2019 outburst. Our data set includes coverage from radio through bands 17 different instruments/telescopes, encompasses 19 epochs over a 7 month period, resulting in one most well-sampled sets XRB outburst date. With our data, compile model...
We present a numerical investigation of dead, or relic, radio galaxies and the environmental impact that galaxy activity has on host cluster. perform axisymmetric hydrodynamical calculations light, supersonic, back-to-back jets propagating in β-model galaxy/cluster atmosphere. then shut down jet let resulting structure evolve passively. The dead source undergoes an initial phase pressure driven expansion until it achieves equilibrium with its surroundings. Thereafter, buoyancy forces drive...
<i>Aims. <i/>A detailed study of the spectrum and variability source HESS J1745-290 in Galactic Center (GC) region using new data from H.E.S.S. array Cherenkov telescopes is presented. Flaring activity quasi periodic oscillations (QPO) are investigated.<i>Methods. <i/>The image analysis performed with a combination semi-analytical shower model statistical moment-based Hillas technique. The lightcurves derived likelihood method based on spectral shape hypothesis. Rayleigh tests Fourier GC...
<i>Aims. <i/>Recent theoretical predictions of the lowest very high energy (VHE) luminosity SN 1006 are only a factor 5 below previously published HESS upper limit, thus motivating further in-depth observations this source.<i>Methods. <i/>Deep at VHE energies (above 100 GeV) were carried out with stereoscopic system (HESS) Cherenkov Telescopes from 2003 to 2008. More than h data have been collected and subjected an improved analysis procedure.<i>Results. <i/>Observations resulted in...