Ewan O'Sullivan

Welcome

I am an astrophysicist working in the mission planning team for the Chandra X-ray Observatory at the Harvard-Smithsonian Center for Astrophysics. My own research speciality is the study of galaxy groups, particularly in the X-ray and radio bands, with interests in elliptical galaxies and galaxy clusters. Until recently I also worked in another field, as a software developer in the Atmospheric Measurements group, preparing for the TEMPO atmospheric pollution monitoring mission, and helping with related projects involving pollution monitoring from space. These pages focus on my astrophysics research.

Recent results

A lot of my recent work has involved the Complete Local-volume Groups Sample, a set of around 50 galaxy groups selected to allow us to explore the population of such systems in the nearby universe, examine their properties, and investigate the role of the supermassive black holes in their central galaxies in regulating the thermal balance of their halos of 10 million K gas. More details of the survey can be found on the CLoGS webpage.

Optical/NIR image (white) of the galaxy group Stephan's Quintet, overlaid with Chandra X-ray emission (blue) tracing the famous shock ridge, JWST infrared emission (red) tracing dust and star formation, and MeerKAT neutral hydrogen emission (pale green) tracing cold neutral gas in the galaxy disks and tidal tails. Major galaxies and structures are labelled, including the star formation regions SQ-A & B

I also like to work on individual systems which are exemplars of interesting physical processes. One such system, perhaps the most famous galaxy group in the sky, is Stephan's Quintet, in which the intruder galaxy NGC 7318B has collided with a group of four other galaxies at around 1000 km/s (2.2 million miles per hour). Previous tidal interactions drew gas and stars out of the galaxies in the main group into long tidal tails and filaments still visible today. The disk of the intruder galaxy has crashed into one of these, shock-heating the cold neutral hydrogen up to about 10 million Kelvin, and accelerating electrons to relativistic velocities, producing radio continuum emission. The resulting ridge of shocked emission is shown in blue in the image above.

My colleague Kamlesh Rajpurohit collected observations of the Quintet from the MeerKAT, GMRT, VLA, and LOFAR radio observatories. With these we were able to map the cold neutral hydrogen in the galaxy disks and tidal structures, as well as using the radio continuum emission to constrain the age and dynamics of the collision shock. We now know the collision to have started 20-25 million years ago at the north end of the shock ridge, and to have finished only about 5 million years ago in the south, with the intruder galaxy moving toward us almost exactly along our line of sight. More detail can be found in our two papers: A MeerKAT View of the Neutral Atomic Gas in Stephan's Quintet and A radio continuum view of Stephan's Quintet: age, dynamics and origin of the shock.

What's new

2026/08/28: Our second paper on Stephan's Quintet, "https://arxiv.org/abs/2608.26461", is accepted by ApJ and posted to the arXiv. We carried out in-depth multi-band radio imaging of the group and its central shock ridge, and made the best available estimate of the age and dynamics of the collision that produced the radio and X-ray emission.
2026/04/01: Francesco Ubertosi's latest paper on NGC 5044, confirming HI clouds within 10-20 pc of the AGN and measuring the expansion rate of the radio jets, accepted for publication in ApJ, and posted to the arXiv.
2026/03/31: Our new paper, "A MeerKAT view of the Neutral Atomic Gas in Stephan's Quintet" accepted by ApJ and posted to the arXiv. We mapped the group in HI, finding previously-undetected gas in two galaxies, tracing bridges linking NGC 7319 to the shock ridge, and providing a modern view of the system for comparison with other wavebands.
2026/03/24: Gave a talk in the CfA's Galaxy Cluster Group meeting, entitled "Stephan's Quintet: A MeerKAT view of shocks in low-mass galaxy groups" - showing off our recent work and some of the wonderful images available of the group. Slides available on the presentations page.
2026/02/18-20: Attending the AGN & Energy Flows workshop at the Center for Computational Astrophysics.
2025/12/03: Dominque Eckert's paper showing the the X-GAP groups are inconsistent with cosmological models with strong AGN feedback submitted to A&A and posted on arXiv.
2025/11/04: The Advanced X-ray Imaging Satellite Community Science Book, for which I contributed a short section on spiral-rich groups, published on arXiv.
2025/10/04: Francesco Ubertosi's paper on offsets between X-ray and Hα gas and supermassive black holes in groups and clusters accepted by ApJ and posted to arXiv. The paper shows the critical connection between cool gas and AGN feedback.
2025/09/08-12: Attending Magnetic Fields and Cosmic Rays across Diverse Scales: What's Next? a conference we're holding here at the Center for Astrophysics, and speaking on shock driven radio emission in my all-time favourite galaxy group, Stephan's Quintet (copy on the presentations page).
2025/08/09: Francesco Ubertosi's paper on the young radio source in the rapidly star-forming BCG of CHIPS 1911+4455 published by ApJ here and covered in the NRAO newsletter: Astronomers Catch Supermassive Black Hole in the Act of "Waking Up".
2025/05/09: Kamlesh Rajpurohit's paper on the properties of the largest radio halos in massive galaxy clusters submitted to ApJ and posted at arXiv:2505.05415.
2025/05/05: Kamlesh Rajpurohit's image of the spectacular double radio relic in the cluster PSZ2G181.06+48.47 featured by AAS Nova.
2025/03/13: Chris Riseley's paper on the highly unusual magnetized fossil radio plasma structure in HCG 15 accepted for publication in A&A and posted at arXiv:2503.08840.
2025/01/15: Two papers on the double-relic cluster PSZ2 G181.06+48.47 submitted by Andra Stroe and Kamlesh Rajpurohit, and posted to arXiv here and here.
2025/01/03: Kamlesh Rajpurohit's paper on our multi-wavelength radio study of NGC 5044 is submitted and posted at arXiv:2501.02076. It presents the first detection of HI in the galaxy via the absorption signature of cold gas clouds near the AGN, and the first consistent multi-band continuum picture of the galaxy.
2024/12/18: My paper on the compact group HCG 57 is accepted by ApJ. We used Chandra and XMM to explore the properties of the group and its galaxies, and added optical IFU data to look into the shocked gas bridge linking two of the major galaxies, HCG 57A/D, which recently collided at 650-750 km/s. Paper posted at at arXiv:2412.13055.
2024/12/03-06: Attending 25 Years of Science with Chandra in Boston, MA, and presenting a poster on my favourite cluster-central quasar, IRAS 09104+4109 (copy on the presentations page).
2024/11/22: Bjorn Emonts' paper on the molecular gas structure and kinematics in Stephan's Quintet, based on ACA and CARMA data, is accepted by ApJ and posted at arXiv:2411.14310.
2024/09/25: Francesco Ubertosi's paper examining the history of AGN activity in Abell 496 accepted by A&A and posted at arXiv:2409.15440.
2024/09/10: Gerrit Schellenberger's latest work on high frequency variability in the low-luminosity, ADAF-powered AGN of NGC 5044 submitted to ApJ and posted at arXiv:2409.06039.
2024/09/03-06: Attending Galaxy Clusters & Radio Relics II here at the CfA, presenting Kamlesh Rajpurohit's work NGC 741. A copy of my slides is on the presentations page.
2024/08/28: Kamlesh Rajpurohit's paper describing the spectacular head-tail radio galaxy diving through the NGC 741 group submitted to ApJ and posted at arXiv:2408.15197.
2024/05/24: My paper on the hot core of the group-dominant elliptical galaxy NGC 777 accepted for publication in ApJ and posted at arXiv:2405.13667.
2024/05/22: Francesco Ubertosi's work on jet reorientation gets a Chandra image release: Spotted - "Death Star" Black Holes in Action!
2024/03/08: Tom Rose's paper using absorption line observations to separate out the infalling population of molecular clouds in the cores of 8 massive galaxies submitted to MNRAS and posted to arXiv.
2024/01/12: Proposal for Smithsonian's internal Physical Sciences funding call, titled "Feeding your SuperMassive Black Hole: from the cooling flow to the accretion flow" approved.
2024/01/08: Francesco Ubertosi visiting our group at the CfA for the next couple of months, following up his work on jet reorientation in cluster-central galaxies.
2023/12/21: Luca Rossignoli's paper on the possibility of sloshing-regulated feedback in Abell 2495 accepted by Apj and posted to the arXiv.
2023/12/06: Francesco Ubertosi's paper on jet reorientation in group- and cluster-dominant galaxies, based on work done while visiting our group at CfA, accepted by ApJ and posted to the arXiv.
2023/08/21: ALMA proposal to carry out an absorption line study of NGC 4261 approved.
2023/07/25: New Chandra proposal approved, targetting the cooling filaments in CLoGS group NGC 410.
2023/06/13-16: I'm attending The X-ray Universe 2023 in Athens, speaking on CLoGS. A copy of the slides is on the presentations page.
2023/04/07: Attended the successful launch of TEMPO from Cape Canaveral. NASA launch video.
2023/03/22: Looks like I'll be attending and speaking at The X-ray Universe 2023 this June, in Athens.
2023/03/16: Gerrit Schellenberger's paper on AGN feedback in the group-central galaxy NGC 6338 accepted by ApJ and posted to the arXiv.
2023/03/12: My GMRT proposal to look for remnant radio emission from past AGN outbursts in NGC 777 has been accepted.
2023/03/10: Francesco Ubertosi's paper using cluster-central GPS radio sources to look at the conditions that trigger feedback submitted to A&A and posted at the arXiv.
2023/01/07: Phil Appleton's paper using JWST data to look at some of the complex shocked multiphase gas in Stephan's Quintet submitted to ApJ and posted to arXiv.
2022/12/19: I am speaking (remotely) on the CLoGS sample at The Cosmic Crowd in the Universe, a symposium to mark Somak Raychaudhury's tenure as Director of IUCAA. A copy of the slides is on the presentations page.
2022/11/24: Our XMM-Newton proposal to observe more of Pratik Dabhade's SAGAN cluster-central giant radio galaxies partially approved: 4 targets at B priority, the remaining 6 at C priority.
2022/10/11: Added listings on the publications page for the remote sensing and pollution-related papers which my old colleagues in the Atmospheric Measurements group have been kind enough to include me on.
2022/08/31: Patricio Lagos' paper using ionization and metallicity indicators to investigate the origin of the warm gas in our CLoGS group-dominant galaxies accepted by MNRAS and posted on arXiv.
2022/08/25: Our MeerKAT proposal to map polarisation along the long radio tail of NGC 741 approved at B-priority.
2022/07/26: Two new Chandra proposals approved, one looking at a pair of giant radio galaxies drawn from Pratik Dabhade's SAGAN project, the other to look at some rare mini-halo hosting clusters identified in the MeerKAT Galaxy Cluster Legacy Survey.
2022/06/28: Ilani Loubser's paper on the stellar kinematics of the 18 CLoGS group-dominant galaxies covered by MUSE accepted by MNRAS and posted on the arXiv.
2022/06/20-24: I'll be attending and speaking at the conference Multiphase Feeding and Feedback II in Sexten, Italy. Delayed from two years ago owing to the pandemic. Talk posted on the presentations page.
2022/06/08: Lyla Jung's paper on the properties of group-central galaxies in the Romulus simulations accepted by MNRAS and posted to arXiv.
2022/05/25: Valeria Olivares' paper on MUSE observations of 18 CLoGS group-dominant galaxies accepted by A&A and posted at the arXiv.
2022/04/14: New paper on heating by non-central radio galaxies in clusters accepted by MNRAS and posted to arXiv. This was a project carried out and written up by Ruchika Seth as part of her Ph.D., and submitted after her untimely death.
2021/12/17: Konstantinos Kolokythas' paper on the star formation and gas content in the CLoGS group-dominant galaxies accepted by MNRAS and posted to the arXiv.
2021/12/9: Two XMM-Newton proposals approved at A priority, one for deeper observations of two CLoGS groups with unusually high cold gas content in their dominant galaxies, and a large program led by Dominique Eckert to measure the IGM properties of 40 SDSS/RASS-selected groups out to R₅₀₀.
2021/12/6-9: Remotely attending Science At Low Frequencies VIII to see what's new in low-frequency radio astronomy.
2021/11/18: Gerrit Schellenberger's latest paper, on a weak, steep spectrum radio relic in the low mass galaxy cluster Abell 2108, accepted by ApJ and posted at arXiv.
2021/11/03: Romana Grossová's paper on VLA observations of nearby bright early-type galaxies accepted for publication and posted at arXiv.
2021/10/19: Conference proceedings paper on the cluster-central compact steep spectrum radio source 1321+045, from the 6th Workshop on Compact Steep Spectrum and Gigahertz Peaked Spectrum radio sources, accepted by AN and posted at arXiv:2110.08358.
2021/07/23: Two of my Chandra proposal approved, one on the CLoGS group NGC 777, and a Large Project on the cluster-central quasar IRAS 09104+4109.
2021/06/28: Nazma Islam's paper announcing the XMM-Newton Galaxy Atlas accepted by ApJS and posted at arXiv:2106.14937
2021/05/26: Gave a (remote) talk on AGN feedback in galaxy groups at the Galactic Fidelity seminar, run by the South African Center for Radio Astronomy Techniques and Technologies.
2021/05/14: My first VLBA proposal as PI, targeting my favourite cluster-central quasar, approved at B priority.
2021/05/11: Review paper on Feedback from AGN in Galaxy Groups published (early access) in Universe.
2021/05/10-14: Remotely attending the 6th Workshop on Compact Steep Spectrum and Gigahertz Peaked Spectrum radio sources. My talk is up on the presentations page.
2021/04/26: Starting new job in the Science Mission Planning team of the Chandra X-ray Center.
2021/04/13: My paper on the cluster-central CSS radio galaxy 1321+045 accepted for publication and posted at arXiv:2104.04548.
2021/03/18: Looks like I'll be (remotely) attending the 6th Workshop on Compact Steep Spectrum and Gigahertz Peaked Spectrum radio sources to learn a bit about these young, small-scale objects!
2021/02/24: Thomas Pasini's paper on the disturbed cool-core cluster Abell 1668 accepted for publication and posted at arXiv:2102.11299.
2020/12/18: My image of the group-group merger NGC 6338 (currently shown above) included in the 2021 Chandra calendar.
2020/12/04: Deeper XMM-Newton observation of non-cool-core CLoGS group NGC 1453 approved at C priority.
2020/10/28: Gerrit Schellenberger's paper on VLBA observations of NGC 5044, which reveal a new cycle of jet activity, accepted by ApJ and posted at arXiv:2010.13804.
2020/10/01: GMRT proposal to follow up our earlier work on NGC 6338 approved.
2020/09/30: TEMPO team wins NASA Group Achievement Award "for outstanding performance in development of the Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument".
2020/09/16: Hsi-An Pan's paper on the properties and origin of the offset Hα cloud in the northern core of the NGC6338 group accepted and posted to arXiv:2009.06656.
2020/09/15: Konstantinos Kolokythas has a post on feedback in galaxy groups (featuring an image I made of NGC 1550) at the Oxford University Press site: How old galaxy groups stay active in retirement.
2020/07/13: Thomas Pasini's paper on the properties of the populations of central radio galaxies in groups and clusters accepted by MNRAS and posted at arXiv:2007.04999.
2020/06/11: Ilani Loubser's paper on the stellar and dynamical mass profiles of 25 brightest cluster galaxies accepted for publication in MNRAS and posted at arXiv:2006.05706.
2020/05/28: Konstantinos Kolokythas' paper on the NGC 1550 galaxy group, and the impact of sloshing on its radio source, accepted by MNRAS and posted at arXiv:2005.12950.
2020/01/15: ~~Looks like I'll be speaking at Multiphase Gas in Galaxy Groups in Charlottesville VA this June, followed rapidly by the Multiphase AGN Feeding and Feedback II workshop in Sexten, Italy, in early July.~~ Both meetings postponed at least a year owing to COVID-19.
2019/12/17: Our work on the violent group-group merger around NGC 6338 gets a Chandra image release: Galaxy Gathering Brings Warmth.
2019/12/3-6: Attending the 20 Years of Chandra Science Symposium in Boston, MA, and presenting two posters, one on the CLoGS sample, the other on the group-group merger NGC 6338.
2019/10/15: Thomas Pasini's paper on cooling in the cluster Abell 2495 accepted by ApJ and posted to the arXiv
2019/09/23: I'll be attending the 20 Years of Chandra symposium here in Boston this December, presenting posters on CLoGS and the merging group NGC 6338.
2019/09/8-13: Attended the X-ray Astronomy 2019 conference in Bologna, Italy, speaking about the CLoGS project.
2019/07/26: CLoGS paper III, Konstantinos Kolokythas' study of the radio properties of the full 53-group sample accepted for publication and public at arXiv:1907.10768.
2019/07/25: Gerrit Schellenberger's paper on the quadruple-merger cluster Abell 1758 accepted and public at arXiv:1907.10581.
2019/07/11: Chandra proposal approved, this one targeting an unusual very young radio galaxy just beginning the process of heating its surrounding galaxy cluster.
2019/06/19: My paper describing the violent group-group merger around NGC 6338 accepted and public at arXiv:1906.07710.
2019/06/05: Looks like I'll be attending and speaking at the X-ray Astronomy 2019 meeting in Bologna in September.
2019/03/26: 20 hours of uGMRT band 3 observations of AGN feedback in galaxy groups approved.
2019/03/18-22: Attended and spoke at The Metre Wavelength Sky II in Pune, India, at which Konstantinos Kolokythas' also presented a poster on the sample. Jan Vrtilek also presented a poster on the project at the 17th AAS HEAD meeting in Monterey, CA.
2018/12/31: It looks like I'll be giving a talk at The Metre Wavelength Sky II conference in Pune, India, in March. Looking forward to seeing friends at NCRA and IUCAA!
2018/07/31: Konstantinos Kolokythas' paper on the central radio galaxies of the 26-group CLoGS high-richness subsample accepted and public at arXiv:1807.11095.
2018/7/24: Paper describing our CO survey of the 53 CLoGS group-dominant ellipticals accepted and public at arXiv:1807.09110.
2018/3/28: Pieter van Dokkum's Nature article describing an ultra-diffuse galaxy with little or no dark matter, for which I am a co-author, released. Picked up by, among others, The Guardian. Accompanying ApJ letter preprint available here.
2018/2/23: Ilani Loubser's paper comparing the velocity profiles of CLoGS group-dominant ellipticals with those of brightest cluster galaxies accepted and posted to the arXiv
2017/11/3: Deep CO observations of two dominant ellipticals in X-ray bright cool core groups with the IRAM 30m telescope approved and scheduled for late December.
2017/10/17: Paper on the origin of the complex X-ray, radio and HI structures in CLoGS group NGC 5903 accepted for publication and public at arXiv:1708.03555.
2017/8/14: CLoGS paper I, describing the sample and the X-ray properties of the richer groups, accepted by MNRAS and public at arXiv:1708.03555.
2017/7/17: My proposal to observe four compact groups with Chandra and XMM-Newton is approved.
2017/7/4: Proposal to observe CO in our remaining southern groups with the ESO APEX telescope approved at A priority.
2017/6/12: Larry David's latest paper on the X-ray brightest group in the sky, NGC 5044, accepted for publication and on the preprint server today, at arXiv:1706.02956
2017/5/15: CO observations of another 9 CLoGS central galaxies approved with the IRAM 30m telescope, as well as NOEMA observations of quasar-in-a-cooling-flow CL09 (hopefully 4th time lucky), both at A priority.
2016/9/6: Looks like I'm going to be speaking about the CLoGS project at The Physics of Groups and Galaxy Properties therein in Paris, 12-15 December.
2016/7/18: Proposed joint Chandra and XMM-Newton observations of the disturbed group NGC 6338 are approved.
2016/2/17: Presented my first talk on TEMPO, as a lunch talk for the High Energy Astrophysics Division here at SAO. A PDF copy of the slide is on the presentations page.
2015/9/8-10: Attended Exploring the Hot and Energetic Universe: The first scientific conference dedicated to the Athena X-ray observatory at ESAC in Spain
2015/7/16: Two Chandra proposals targeting CLoGS groups approved. These observations will build on the initial XMM-Newton observations, helping us understand the physical processes shaping the hot gas component of the groups.
2015/5/16: Added a new image of the night sky over Boston - a one-hour stacked exposure to test the effect of light pollution - to the non-work page.
2015/4/27: Two NOEMA proposals accepted (at B priority): A third try for quasar-in-a-cooling-flow CL09, and Stephen Hamer's proposal to map the most CO-rich system discovered in the first part of our IRAM 30m survey of CLoGS group-dominant ellipticals.
2015/3/26: Two papers on the arXiv today: Konstantinos Kolokythas' study of the powerful group-central radio source 3C 270 in NGC 4261, and Biao Zhang's study of merging cluster PLCK G036.7+14.9, for which I helped with the XMM analysis.
2015/3/15: I've been accepted on to the "Physics of Groups and Clusters" working group for the Athena mission.
2014/7/17: A spectacular crop of Chandra proposals approved! My PI proposal for a deep (155ks) observation of CLoGS group NGC 5903 got time, and I was co-I on a joint Chandra/XMM observation of the NGC 741 group and an ultra-deep (340ks) observation of NGC 5044, led by my collaborators Jan Vrtilek and Larry David. I'm also a co-I on a Chandra archive proposal led by Dong-Woo Kim, aimed at producing an atlas of elliptical galaxies observed by Chandra. Quite a haul!
2014/7/14: Larry David's paper on ALMA mapping of molecular gas in NGC 5044 posted to the arXiv.
2014/7/9-11: Presented a talk on the hot IGM in spiral-rich groups at the X-ray View of Galaxy Ecosystems workshop here in Boston. A PDF copy of the talk is now up on the presentations page.
2014/6/10: I will be attending the X-ray View of Galaxy Ecosystems workshop here in Boston, July 9-11, and speaking about the formation of the intra-group medium.
2014/3/10: Starting a new job, as a software developer for the TEMPO atmospheric pollution monitoring mission.
2014/2/20: Proceedings paper for The Metrewavelength Sky conference posted on arXiv.
2013/12/9: Deep XMM-Newton pointing of compact group HCG 15 awarded B-priority time.
2013/12/9-13: At The Metrewavelength Sky conference, hosted by NCRA/TIFR, with several other members of the CLoGS team. Slides from my talk can be found on the presentations page.
2013/11/18: The NGC 5044 abundance map image is ESA's space science image of the week.
2013/10/21: The NGC 5044 abundance map image has been chosen as HEASARC High Energy Astrophysics image of the week.
2013/10/08: Paper on the impact of sloshing on the abundance distribution of NGC~5044 accepted by MNRAS and posted to the arXiv. An accompanying image I put together has been accepted into the XMM gallery, and posted on my flickr feed.
2013/09/18: Updated the non-work page with a couple of new-ish photos.
2013/09/12: Two GMRT proposals accepted, one to replace some bad data on CLoGS groups, one to map the neutral hydrogen structure in NGC 5903.
2013/09/6: Phil Appleton's paper on C⁺ and H₂O emission from the shock in Stephan's Quintet, for which I provided some Chandra X-ray analysis, accepted by ApJ and posted to the arXiv.
2013/08/5: XMM observation of NGC 5903 delivered.
2013/06/27-28: Short visit to Birmingham to talk with students working on various aspects of the CLoGS project.
2013/05/20: Stefano Ettori's paper on the sloshing, cool-core cluster Zw1742+3306, for which I prepared spectral maps, accepted by A&A and posted on the arXiv.
2013/05/6-10: Observing run at the IRAM 30m telescope, looking for CO in CLoGS group-central ellipticals.
2013/03/01: HST proposal to look at IRAS 09104+4109 submitted.
2013/01/09-10: Visiting Birmingham to talk to collaborators, work on papers, and catch up on the gossip.
2012/12/10: Alastair Sanderson's latest paper, The baryon budget on the galaxy group/cluster boundary, for which I did the XMM ESAS analysis, accepted for publication in MNRAS and posted at arXiv:1212.1613.
2012/12/06: Awarded 8 hours of LOFAR cycle 0 time to observe Stephan's Quintet.
2012/12/04: XMM-Newton proposal to observe NGC 5903, a CLoGS group with a very unusual combination of diffuse radio emission and cold neutral hydrogen, approved with A priority.
2012/11/14: Two CO proposals accepted: one to search for molecular gas in CLoGS group central galaxies with the IRAM 30m telescope, one to use the Plateau de Bure interferometer to map the distribution of CO in the optical filaments around the hyper-luminous infrared galaxy and cluster-central type-II quasar IRAS 09104+4109, which I wrote a paper on earlier this year.
2012/09/17: NASA Astrophysical Data Analysis Program (ADAP) proposal partially approved, providing support for analysis of 22 CLoGS groups observed by XMM-Newton.
2012/09/05: My talk and poster from the IAU now listed on the Presentations page.
2012/08/20-25: At the IAU in Beijing, speaking in the Special Session Cosmic Evolution of Groups and Clusters.
2012/06/25: Simona Giacintucci's paper looking into recurrent radio outbursts in NGC 1407 accepted by ApJ and posted to the arXiv.
2012/06/07: Paper accepted by MNRAS and posted to the arXiv: A Giant Metrewave Radio Telescope / Chandra view of IRAS 09104+4109: A type 2 QSO in a cooling flow.
2012/05/25: Duncan Forbes' paper comparing the radial distribution of hot gas and globular clusters around giant ellipticals accepted by MNRAS.
2012/04/17: Fill Humphrey's paper on NGC 1521, on which I'm a co-author, submitted to ApJ and posted to the arXiv.
2012/03/28: Fourth CLoGS GMRT proposal accepted with full time allocation, meaning that the full CLoGS sample will be radio-complete at 610/235 MHz by autumn 2012! Deep 150~MHz observations of three of our most interesting systems also approved.
2012/02: Started my 8-month visit to Harvard-Smithsonian Center for Astrophysics.
2012/01/09: Visiting the National Centre for Radio Astrophysics in Pune, India, for a month to study low-frequency radio analysis techniques and do a little observing at the Giant Metrewave Radio Telescope.
2011/12/07: Two proposals approved: 104 ks of XMM-Newton time to complete the first half of the CLoGS group sample, and 12.5 hours of EVLA time to look at one of my favourite radio galaxies.
2011/10/26: Added a star trails image and video from some recent evenings at the Wast Hills observatory to the Non-work page.
2011/09/24: GMRT proposal `CLoGS - The Complete Local-Volume Groups Sample, part 3 ' awarded 100% of time requested!
2011/07/25-29: In Leiden, attending the Lorentz Center workshop Groups and Clusters of Galaxies: Confronting Theory with Observations.
2011/07/08-15: In Boston to attend Structure in Clusters and Groups of Galaxies in the Chandra Era and work with my collaborators at the Harvard-Smithsonian Center for Astrophysics.
2011/06/27-30: At The X-ray Universe 2011 meeting in Berlin.
2011/06/14: Paper accepted by MNRAS and posted to the arXiv: Interaction between the intergalactic medium and central radio source in the NGC 4261 group of galaxies.
2011/05/04: Gave a seminar to the Extragalactic and Cosmology group at Durham University.
2011/04/15: Looks like I'll be giving a talk at The X-ray Universe 2011 in Berlin, in June. The title is `AGN feedback in galaxy groups: a combined X-ray/low-frequency radio view'.
2011/04/14: Paper accepted by ApJ and posted to the arXiv: Heating the hot atmospheres of galaxy groups and clusters with cavities: the relationship between jet power and low-frequency radio emission.
2011/03/21: My recent work on AGN feedback in the poor cluster AWM 4 featured in the SAO Weekly Science Update.
2011/03/18: GMRT proposal `CLoGS - The Complete Local-Volume Groups Sample, part 2' awarded 100% of time requested!
2011/03/07: Main paper for our GMRT/X-ray study of groups accepted and posted to the archive: Giacintucci et al. 2011.
2011/02/03: Added link to website for Structure in Clusters and Groups of Galaxies in the Chandra Era, the 2011 Chandra workshop, for which I'm a member of the SOC.
2011/01/23-30: Visiting the Harvard-Smithsonian Center for Astrophysics.
2011/01/18: Web pages for the Complete Local-Volume Groups Sample online.
2010/12/06-10: Visiting the Harvard-Smithsonian Center for Astrophysics to work with my collaborators and catch up on changes since I left last year.
2010/12/01: XMM-Newton proposal `CLoGS - The Complete Local-Volume Groups Sample' awarded 175ks of time! (+104ks C-time)
2010/11/11-12: In Germany to serve on the XMM-Newton galaxies time allocation panel.
2010/10/11-15: At LOFAR Data Analysis School 2010.
2010/10/04: Two papers accepted and posted to the arXiv: O'Sullivan et al. on AGN driven enrichment in AWM4, and David et al. on AGN driven weather and multiphase gas in NGC 5044.
2010/09/27-28: This year's Birmingham-Nottingham Extragalactic Workshop AGN: populations, parameters and powers, my talk now up on the posters and presentations page.
2010/09/08: GMRT proposal `CLoGS - The Complete Local-Volume Groups Sample' awarded time!
2010/07/13: Chandra Archive proposal `The History of AGN Feedback in Galaxy Groups: A Combined X-ray/Low-Frequency Radio Sample' approved!
2010/07/13: Added posters and presentations page.
2010/07/04: First announcement of this year's Birmingham-Nottingham Extragalactic Workshop AGN: populations, parameters and powers.
2010/06/10: Worrall et al. paper on radio/X-ray jets in NGC 4261 accepted by MNRAS and posted to the arXiv.
2010/05/13: Astrophysics group seminar at the University of Bristol.
2010/05/03: O'Sullivan et al. paper on AWM 4 accepted by MNRAS and posted to the arXiv.
2010/04/22-29: Visit to the Astrophysics Group of the University of Crete to work with Andreas Zezas, including a lunch talk.
2010/04/13 : This page goes live.

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