From the Circumnuclear Disk in the Galactic Center to thick, obscuring tori of AGNs: modeling the molecular emission of a parsec-scale torus as found in NGC 1068

Galaxie

Governing the anthropocene: agency, governance, knowledge

The growing body of literature on the idea of the Anthropocene has opened up serious questions that go to the heart of the social and human sciences. There has been as yet no satisfactory theoretical framework for the analysis of the Anthropocene debate in the social and human sciences. The notion of the Anthropocene is not only a condition in which humans have become geologic agents, thus signalling a temporal shift in Earth history: it can be seen as a new object of knowledge and an order of governance. A promising direction for theorizing in the social and human science is to approach the notion of the Anthropocene as exemplified in new knowledge practices that have implications for governance. It invokes new conceptions of time, agency, knowledge and governance. The Anthropocene has become a way in which the human world is re-imagined culturally and politically in terms of its relation with the Earth. It entails a cultural model, that is an interpretative category by which contemporary societies make sense of the world as embedded in the Earth, and articulate a new kind of historical self-understanding, by which an alternative order of governance is projected. This points in the direction of cosmopolitics – and thus of a ‘Cosmopolocene’ – rather than a geologization of the social or in the post-humanist philosophy, the end of the human condition as one marked by agency

Active Galactic Nuclei at the Crossroads of Astrophysics

Over the last five decades, AGN studies have produced a number of spectacular examples of synergies and multifaceted approaches in astrophysics. The field of AGN research now spans the entire spectral range and covers more than twelve orders of magnitude in the spatial and temporal domains. The next generation of astrophysical facilities will open up new possibilities for AGN studies, especially in the areas of high-resolution and high-fidelity imaging and spectroscopy of nuclear regions in the X-ray, optical, and radio bands. These studies will address in detail a number of critical issues in AGN research such as processes in the immediate vicinity of supermassive black holes, physical conditions of broad-line and narrow-line regions, formation and evolution of accretion disks and relativistic outflows, and the connection between nuclear activity and galaxy evolution.Comment: 16 pages, 5 figures; review contribution; "Exploring the Cosmic Frontier: Astrophysical Instruments for the 21st Century", ESO Astrophysical Symposia Serie

The Physics of Star Cluster Formation and Evolution

© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00689-4.Star clusters form in dense, hierarchically collapsing gas clouds. Bulk kinetic energy is transformed to turbulence with stars forming from cores fed by filaments. In the most compact regions, stellar feedback is least effective in removing the gas and stars may form very efficiently. These are also the regions where, in high-mass clusters, ejecta from some kind of high-mass stars are effectively captured during the formation phase of some of the low mass stars and effectively channeled into the latter to form multiple populations. Star formation epochs in star clusters are generally set by gas flows that determine the abundance of gas in the cluster. We argue that there is likely only one star formation epoch after which clusters remain essentially clear of gas by cluster winds. Collisional dynamics is important in this phase leading to core collapse, expansion and eventual dispersion of every cluster. We review recent developments in the field with a focus on theoretical work.Peer reviewe

Scholarly publishing depends on peer reviewers

The peer-review crisis is posing a risk to the scholarly peer-reviewed journal system. Journals have to ask many potential peer reviewers to obtain a minimum acceptable number of peers accepting reviewing a manuscript. Several solutions have been suggested to overcome this shortage. From reimbursing for the job, to eliminating pre-publication reviews, one cannot predict which is more dangerous for the future of scholarly publishing. And, why not acknowledging their contribution to the final version of the article published? PubMed created two categories of contributors: authors [AU] and collaborators [IR]. Why not a third category for the peer-reviewer?Scopu

Neutral hydrogen absorption in NGC 1068 and NGC 3079

Copyright American Astronomical Society [Full text of this article is not available in the UHRA]Peer reviewe

H 2O and OH Masers as Probes of the Obscuring Torus in NGC 1068

Original article can be found at: http://adsabs.harvard.edu/abs/ Copyright American Astronomical Society. DOI: 10.1086/177187 [Full text of this article is not available in the UHRA]We report the discovery of OH masers and positionally resolved H_2_O maser emission in the nucleus of NGC 1068. The brightest H_2_O masers are associated with the radio continuum component that is probably the location of the central engine (Gallimore, Muxlow, and coworkers). These masers trace a ~50 mas (~5 pc) roughly linear velocity gradient along P.A 94^deg^ +/- 4^deg^, which is almost at right angles to the local radio jet axis. The kinematics of the masers are well described as an edge-on Keplerian disk surrounding a large central mass concentration (black hole?). The inner radius of the maser disk is ~> 1.3 pc, and the outer radius is ~2.5 pc, assuming a distance of 22 Mpc. The mass within the inner radius, normalized to the best-fit disk parameters, is 4.4 x 10^7^ M_sun_ x (r_in_/1.3 pc) (ν_max_/378 km s^-1^)^2^. These masers might occur in the parsec-scale torus thought to obscure the central engine. Radio continuum emission fills the region interior to the H_2_O masers, in agreement with the prediction that the continuum emission is thermal free-free radiation from the inner face of the molecular torus (Gallimore and coworkers). The location of-the OH masers and nuclear H I absorption (Gallimore and coworkers), measured with ~1" angular resolution, is consistent with the location of the H_2_O masers associated with the central engine. The H I absorption profile is also consistent with the Keplerian model for the H_2_O maser disk kinematics, and the velocity range of the OH masers is similar to that spanned by both the H I and H_2_O spectral features. It therefore seems likely that the OH masers and H I absorption also originate in the obscuring material surrounding the central engine. The OH masers indicate the presence of a more tenuous molecular medium in the torus, in addition to the denser material traced by the H_2_O maser emission. We have also discovered fainter H_2_O masers located 0.3" (~30 pc) downstream along the radio jet. These masers are too distant from the central engine to arise in a parsec-scale torus. They may instead occur at the shock interface between the radio jet and an intervening molecular cloud. The implication is that H_2_O magamaser emission may probe both circumnuclear disks and shock fronts in other active galactic nuclei.Peer reviewe

MERLIN observations of neutral hydrogen absorption in the Seyfert nucleus of NGC 4151

Peer reviewe