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Related papers: H.E.S.S. observations of massive stellar clusters

200 papers

We critically assess limits on the maximum energy of protons accelerated within superbubbles around massive stellar clusters, considering a number of different scenarios. In particular, we derive under which circumstances acceleration of…

High Energy Astrophysical Phenomena · Physics 2022-08-03 Thibault Vieu , Brian Reville , Felix Aharonian

Pulsar Wind Nebulae (PWNe) represent the most numerous population of TeV sources in our Galaxy. These sources, some of which emit very-high-energy (VHE) gamma-rays, are believed to be related to the young and energetic pulsars that power…

High Energy Astrophysical Phenomena · Physics 2019-08-15 A. Fernández-Barral , O. Blanch , A. Chatterjee , E. de Oña Wilhelmi , D. Fidalgo

The massive red supergiant (RSG) W26 in Westerlund 1 is one of a growing number of RSGs shown to have winds that are ionized from the outside in. The fate of this dense wind material is important for models of second generation star…

Astrophysics of Galaxies · Physics 2015-09-30 Jonathan Mackey , Norberto Castro , Luca Fossati , Norbert Langer

Globular clusters are gravitationally bound stellar systems containing on the order of 100,000 stars. Due to the high stellar densities in the cores of these clusters, close encounters and even physical collisions between stars are…

Astrophysics · Physics 2007-05-23 Christian Knigge

Rich superclusters are the ideal environment for the detection of cluster mergings, because the high peculiar velocities induced by the enhanced local density of the large-scale structure favour the cluster-cluster collisions, in the same…

Astrophysical flares are one of the possible prominent source classes of ultra-high-energy (UHE, $E > 10^{17}$ eV) cosmic rays, which can be detected by recording clusters of extensive air showers in arrays of detectors. The search for…

High Energy Astrophysical Phenomena · Physics 2025-10-01 Jaroslaw Stasielak , Chaitanya Priyadarshi , Dariusz Góra , Nataliia Borodai , Marcus Niechciol , Jan Pękala

Observations of very-high-energy (VHE) gamma-ray emission from supernova remnants (SNR) established them as sources of accelerated particles up to energies of 100 TeV. The dominant process - leptonic or hadronic - responsible for the VHE…

High Energy Astrophysical Phenomena · Physics 2013-07-23 Stephanie Häffner , Ira Jung , Christian Stegmann

The H.E.S.S. experiment is an array of four imaging Cherenkov telescopes located in the Khomas Highlands of Namibia. It has been operating in its full configuration since December 2003 and detects very-high-energy (VHE) gamma rays ranging…

High Energy Astrophysical Phenomena · Physics 2015-03-19 Mathieu de Naurois

Numerical simulations have established that star clusters with densities comparable to the high redshift ($z>6$-$10$) James Webb Space Telescope (JWST) proto globular clusters may build up extremely massive (EMSs; $m_\mathrm{\star}>1000…

Astrophysics of Galaxies · Physics 2026-04-28 Antti Rantala

Nuclear star clusters are among the densest stellar systems known and are common in both early- and late-type galaxies. They exhibit scaling relations with their host galaxy which may be related to those of supermassive black holes. These…

Astrophysics of Galaxies · Physics 2015-12-09 David R. Cole , Victor P. Debattista

We report on the identification of 54 embedded clusters around 217 massive protostellar candidates of which 34 clusters are new detections. The embedded clusters are identified as stellar surface density enhancements in the 2 $\mu$m All Sky…

Astrophysics · Physics 2018-06-19 M. S. N. Kumar , E. Keto , E. Clerkin

Some general features of cosmic ray acceleration are summarized along with some inferences that can be drawn concerning the origin of the UHE component. The UHE luminosity density is found to be similar to that derived for GeV cosmic rays…

Astrophysics · Physics 2010-12-03 R. D. Blandford

It has been postulated that globular clusters could be sources of Very-High Energy (VHE) gamma rays, powered by milli-second pulsars. This could be due to cumulative direct emission or to plerion-type emission driven by colliding winds. In…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Michael McCutcheon

Analyzing the dynamical state of nearby young massive star clusters is essential understanding star cluster formation and evolution during their earliest stages. In this work we analyze the stellar and gas kinematics of the young massive…

Solar and Stellar Astrophysics · Physics 2021-03-03 Peter Zeidler , Elena Sabbi , Antonella Nota , Anna F. McLeod

Observations by the H.E.S.S. system of imaging atmospheric Cherenkov telescopes provide the most sensitive measurements of the Galactic Centre region in the energy range 150 GeV - 30 TeV. The vicinity of the kinetic centre of our galaxy…

Astrophysics · Physics 2008-11-26 C. van Eldik , O. Bolz , I. Braun , G. Hermann , J. Hinton , W. Hofmann

We report new 5.5 GHz radio observations of the massive star cluster Westerlund 1, taken by the Australia Telescope Compact Array, detecting nine of the ten yellow hypergiants (YHGs) and red supergiants (RSGs) within the cluster. Eight of…

Solar and Stellar Astrophysics · Physics 2018-04-04 H. Andrews , D. Fenech , R. K. Prinja , J. S. Clark , L. Hindson

As deep spectroscopic campaigns extend to higher redshifts and lower stellar masses, the interpretation of galaxy spectra depends increasingly upon models for very young stellar populations. Here we present new HST/COS ultraviolet…

Astrophysics of Galaxies · Physics 2021-04-07 Peter Senchyna , Daniel P. Stark , Stéphane Charlot , Jacopo Chevallard , Gustavo Bruzual , Alba Vidal-García

Motivated by recent detections of pulsar wind nebulae in very-high-energy (VHE) gamma rays, a systematic search for VHE gamma-ray sources associated with energetic pulsars was performed, using data obtained with the H.E.S.S. (High Energy…

Astrophysics · Physics 2012-08-27 S Collaboration , S. Carrigan , Y. A. Gallant , J. A. Hinton , Nu. Komin , K. Kosack , C. Stegmann

We report on the latest discovery of an extended Very High Energy (VHE) gamma-ray source near the 67 ms pulsar PSR J1831-0952 during the H.E.S.S. Galactic Plane Survey (GPS). The dispersion measure distance of the pulsar (4.3 kpc) would…

High Energy Astrophysical Phenomena · Physics 2019-08-13 F. Sheidaei , A. Djannati-Ataï , H. Gast

We present the first Chandra X-ray observations of H72.97-69.39, a highly-embedded, potential super-star cluster (SSC) in its infancy located in the star-forming complex N79 of the Large Magellanic Cloud. We detect particularly hard,…