Physical Sciences and Mathematics Commons^™

Variability Of The Blazar 4c 38.41 (B3 1633+382) From Ghz Frequencies To Gev Energies, Niall Smith, Et. Al.

Blackrock Castle Observatory Publications

Context. After years of modest optical activity, the quasar-type blazar 4C 38.41 (B3 1633+382) experienced a large outburst in 2011, which was detected throughout the entire electromagnetic spectrum, renewing interest in this source.

Aims. We present the results of low-energy multifrequency monitoring by the GLAST-AGILE Support Program (GASP) of the Whole Earth Blazar Telescope (WEBT) consortium and collaborators, as well as those of spectropolarimetric/spectrophotometric monitoring at the Steward Observatory. We also analyse high-energy observations of the Swift and Fermi satellites. This combined study aims to provide insights into the source broad-band emission and variability properties.

Methods. We assemble …

Residual Cooling And Persistent Star Formation Amid Active Galactic Nucleus Feedback In Abell 2597, G. R. Tremblay, C. P. O'Dea, S. A. Baum, T. E. Clarke, C. L. Sarazin, J. N. Bregman, F. Combes, M. Donahue, A. C. Edge, A. C. Fabian, Gary J. Ferland, B. R. Mcnamara, R. Mittal, J. B. R. Oonk, A. C. Quillen, H. R. Russell, J. S. Sanders, P. Salomé, G. M. Voit, R. J. Wilman, M. W. Wise

Physics and Astronomy Faculty Publications

New Chandra X-ray and Herschel Far-Infrared (FIR) observations enable a multiwavelength study of active galactic nucleus (AGN) heating and intracluster medium (ICM) cooling in the brightest cluster galaxy (BCG) of Abell 2597 (z= 0.0821). The new Chandra observations reveal the central ≲30 kpc X-ray cavity network to be more extensive than previously thought, and associated with enough enthalpy to theoretically inhibit the inferred classical cooling flow. Nevertheless, we present new evidence, consistent with previous results, that a moderately strong residual cooling flow is persisting at 4–8 per cent of the classically predicted rates in a spatially structured manner …

The 2010 Very High Energy Gamma-Ray Flare And 10 Years Of Multi-Wavelength Observations Of M 87, P. T. Reynolds, Hess, Magic, Veritas, Et. Al.

Physical Sciences Publications

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 very high energy (VHE; E > 100 GeV) γ-ray emission generated in relativistic outflows and the surroundings of supermassive black holes. M 87 has been established as a VHE γ-ray emitter since 2006. The VHE γ-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in …

The Influence Of Soft Spectral Components On The Structure And Stability Of Warm Absorbers In Active Galactic Nuclei, Susmita Chakravorty, Ranjeev Misra, Martin Elvis, Ajit K. Kembhavi, Gary J. Ferland

Physics and Astronomy Faculty Publications

The radiation from the central regions of active galactic nuclei, including that from the accretion disc surrounding the black hole, is likely to peak in the extreme-ultraviolet ∼13–100 eV. However, due to Galactic absorption, we are limited to constrain the physical properties, i.e. the black hole mass and the accretion rate, from what observations we have below ∼10 eV or above ∼100 eV. In this paper, we predict the thermal and ionization states of warm absorbers as a function of the shape of the unobservable continuum. In particular we model an accretion disc at kT_in∼ 10 eV and …

Multiphase Signatures Of Active Galactic Nucleus Feedback In Abell 2597, G. R. Tremblay, C. P. O'Dea, S. A. Baum, T. E. Clarke, C. L. Sarazin, J. N. Bregman, F. Combes, M. Donahue, A. C. Edge, A. C. Fabian, Gary J. Ferland, B. R. Mcnamara, R. Mittal, J. B. R. Oonk, A. C. Quillen, H. R. Russell, J. S. Sanders, P. Salomé, G. M. Voit, R. J. Wilman, M. W. Wise

Physics and Astronomy Faculty Publications

We present new Chandra X-ray observations of the brightest cluster galaxy (BCG) in the cool-core cluster Abell 2597 (z= 0.0821). The data reveal an extensive kpc-scale X-ray cavity network as well as a 15-kpc filament of soft-excess gas exhibiting strong spatial correlation with archival Very Large Array radio data. In addition to several possible scenarios, multiwavelength evidence may suggest that the filament is associated with multiphase (10³–10⁷ K) gas that has been entrained and dredged-up by the propagating radio source. Stemming from a full spectral analysis, we also present profiles and 2D spectral maps of …