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What do astronomers want from the STFC?

Astronomy and Geophysics Oxford University Press 60:2 (2019) 2.13-2.17

Authors:

Stephen Serjeant, James Bolton, Poshak Gandhi, Christiane Helling, Paolo Mazzali, Ben Stappers, Yvonne Unruh, Aprajita Verma

Abstract:

Stephen Serjeant and the STFC's Astronomy Advisory Panel summarize community responses to its consultation on research priorities, undertaken in November 2018.

Getting Connected: An Empirical Investigation of the Relationship Between Social Capital and Philanthropy Among Online Volunteers

Nonprofit and Voluntary Sector Quarterly SAGE Publications 48:2_suppl (2019) 151s-173s

Authors:

Joe Cox, Eun Young Oh, Brooke Simmons, Gary Graham, Anita Greenhill, Chris Lintott, Karen Masters, Royston Meriton

Single-object Imaging and Spectroscopy to Enhance Dark Energy Science from LSST

ArXiv 1903.09324 (2019)

Authors:

Ren茅e A Hlo啪ek, Thomas Collett, Llu铆s Galbany, Daniel A Goldstein, Saurabh W Jha, Alex G Kim, Rachel Mandelbaum, Jeffrey A Newman, Saul Perlmutter, Daniel J Perrefort, Mark Sullivan, Aprajita Verma

The case for a 'sub-millimeter SDSS': a 3D map of galaxy evolution to z~10

(2019)

Authors:

James E Geach, Manda Banerji, Frank Bertoldi, Matthieu Bethermin, Caitlin M Casey, Chian-Chou Chen, David L Clements, Claudia Cicone, Francoise Combes, Christopher Conselice, Asantha Cooray, Kristen Coppin, Emanuele Daddi, Helmut Dannerbauer, Romeel Dave, Matthew Doherty, James S Dunlop, Alastair Edge, Duncan Farrah, Maximilien Franco, Gary Fuller, Tracy Garratt, Walter Gear, Thomas R Greve, Evanthia Hatziminaoglou, Christopher C Hayward, Rob J Ivison, Ryohei Kawabe, Pamela Klaassen, Kirsten K Knudsen, Kotaro Kohno, Maciej Koprowski, Claudia DP Lagos, Georgios E Magdis, Benjamin Magnelli, Sean L McGee, Michal Michalowski, Tony Mroczkowski, Omid Noroozian, Seb Oliver, Dominik Riechers, Wiphu Rujopakarn, Douglas Scott, Stephen Serjeant, Matthew WL Smith, Mark Swinbank, Yoichi Tamura, Paul van der Werf, Eelco van Kampen, Aprajita Verma, Joaquin Vieira, Jeff Wagg, Fabian Walter, Lingyu Wang, Al Wootten, Min S Yun

AGN photoionization of gas in companion galaxies as a probe of AGN radiation in time and direction

Monthly Notices of the Royal Astronomical Society 483:4 (2019) 4847-4865

Authors:

WC Keel, VN Bennert, A Pancoast, CE Harris, A Nierenberg, SD Chojnowski, AV Moiseev, DV Oparin, CJ Lintott, K Schawinski, G Mitchell, C Cornen

Abstract:

漏 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We consider active galactic nucleus (AGN) photoionization of gas in companion galaxies (cross-ionization) as a way to sample the intensity of AGN radiation in both direction and time, independent of the gas properties of the AGN host galaxies. From an initial set of 212 AGN+companion systems, identified with the help of Galaxy Zoo participants, we obtained long-slit optical spectra of 32 pairs that were a priori likely to show cross-ionization based on projected separation or angular extent of the companion. From emission-line ratios, 10 of these systems are candidates for cross-ionization, roughly the fraction expected if most AGNs have ionization cones with 70掳 opening angles. Among these, Was 49 remains the strongest nearby candidate. NGC 5278/9 and UGC 6081 are dual-AGN systems with tidal debris, complicating identification of cross-ionization. The two weak AGNs in the NGC 5278/9 system ionize gas filaments to a projected radius 14 kpc from each galaxy. In UGC 6081, an irregular high-ionization emission region encompasses both AGNs, extending more than 15 kpc from each. The observed AGN companion galaxies with and without signs of external AGN photoionization have similar distributions in estimated incident AGN flux, suggesting that geometry of escaping radiation or long-term variability controls this facet of the AGN environment. This parallels conclusions for luminous QSOs based on the proximity effect among Lyman 伪 absorbers. In some galaxies, mismatch between spectroscopic classifications in the common BPT diagram and the intensity of weaker He ii and [Ne v] emission lines highlights the limits of common classifications in low-metallicity environments.