High-energy astrophysics teleconference 15th September 2006 Files and links at http://www.ph.unimelb.edu.au/~duncang/heat Present: Duncan Galloway (organiser) & Jasmina Lazendic (UMelb); Bryan Gaensler, Zdenka Kuncic, Aimee McNamara, Shami Chatterjee & Gemma Anderson (USyd); Ravi Sood & Sean Farrell (ADFA) & Geoff Bicknell (RSAA); Apologies: Gavin Rowell, Roger Clay, Matt Owers, Andrew Melatos and Christine Chung Welcome, logistics etc. - Friday noon slot seems OK for most. Duncan unavailable in two weeks time, and after that is the HEAD meeting, so the next telecon is tentatively scheduled for October 13th - Phone is OK but it would be nice to get some video. Access grid doesn't seem to be feasible at present, but some other software might work. Not all participants have Macs, so iChat appears to be out; Teamspeak (www.goteamspeak.com) is available for all platforms so will be investigated further for feasibility (Bryan & Duncan?) Introductions & research interests Duncan Galloway - PhD at UTas 2001; two postdocs at MIT, currently Centenary fellow at U. Melbourne (see also summary page). Thermonuclear bursts, particularly as a probe of the neutron-star equation-of-state; ongoing observational programs on accretion-powered millisecond pulsars; and high-resolution X-ray imaging and spectroscopy of low-mass X-ray binaries. Primarily using RXTE, but also XMM-Newton and Chandra. Jasmina Lazendic - PhD at USyd; postdocs at CfA, MIT, currently research associate at U.Melbourne. Multiwavelength observations of SNRs, particularly interested in mixed-morphology remnants, which have shell-type morphology in radio and centrally-peaked thermal X-ray emission. Also CCOs, which are thought to be neutron stars but have no detectable optical counterparts and (mostly) no pulsations. Ravi Sood - PhD 1969 Imperial College, gamma-ray astronomy; gradually moved into X-ray observations, currently professor at ADFA. Since 1998 experimental work with high-voltage balloon-borne X-ray detectors, but more recently working with archival data from satellite X-ray observatories. Sean Farrell - undergrad at Newcastle, currently final-year PhD student @ ADFA (Sood; see also summary page). Originally studying microquasars, more recently moved to studying long-term variations in a high-mass binary X-ray pulsar, 2S 0114+650 using RXTE as well as NIR/radio observations. Leaving shortly for CESR to work with the XMM-Newton survey science centre on millisecond pulsars etc. Bryan Gaensler - PhD at USyd, postdocs at MIT & CfA and teaching at Harvard; currently Fed Fellow at USyd. Specialist in multiwavelength followup observations of interesting things discovered by others (his own words!) Compact objects, pulsar wind nebulae, magnetars etc. Very interested in TcV astronomy (e.g. with the soon-to-be-launched GLAST) and is involved in radio & X-ray followups, and broadband properties of TeV sources. Zdenka Kuncic - undergrad at USyd, Phd at Cambridge, postdocs at ANU, U.Victoria (Canada), and then part-time in space physics at USyd; now full-time lecturer at USyd. Theorist specialising in accretion in compact objects and accretion column structure (with PhD student McNamara). Keen to work more closely with multiwavelength observational data. Aimee McNamara - undergrad in South Africa, currently 1st year PhD student at USyd (Kuncic). Currently involved in modelling the production of Fe K-alpha lines in white dwarf accretion columns, and comparing to observations; hoping to extend these calculations to the neutron-star case. Gemma Anderson - undergrad at UWA, honours at MSO; new PhD at USyd (Gaensler). CHICAGO project - multiwavelength (IR/optical) followup of sources detected in new and archival Chandra/XMM-Newton observations, with the goal of discovering many new sources of widely-varying types - SNRs, AGN, you name it. Shami Chattergee - ugrad at Madras, PhD at Cornell, Jansky Fellow at NRAO/Harvard, recently moved to a postdoc at USyd. High-precision VLBI astrometry of neutron stars to measure velocities, also pulsar winds, bow shock nebulae etc. Geoff Bicknell - theorist working on accretion disks and jets, particularly the magnetic structure and dissipation, and observational signatures in AGN etc. Involved with modeling Blazars for inputs to TeV studies, with Cangaroo and HESS (collaborating with Wagner @ U. Heidelberg). Also interested in GLAST data. Gaensler - giant flares in 1806-20 - December 27, 2004 outburst of the soft-gamma ray repeater SGR 1806-20 was so large as to defy any superlatives to describe it. Enormous energy output, detected by many satellites but so bright as to disable most. - Because of the time of year, couldn't get radio observations until a few days later; 0.2 Jy counterpart expanding at 0.7c, still detectable (with VLA) and is expected to be observeable for the next 15 yr, as a "mini-SNR". Presently the source is ~0.1" across and asymmetric - Model for these sources is a neutron star with ultrastrong magnetic field ~10^15 G; outbursts are caused by rearrangements of the crust. - "Normal" bursts are frequently detected, recently with Swift and INTEGRAL (via the IBAS alert system). - Duncan also working a little on GRBs observed serendipitously with RXTE; cf. with recent Nature papers (courtesy Bryan) Soderberg et al., Nature, 442, 1014 (2006) Mazzali et al., Nature, 442, 1018 (2006) (and references therein) Israel et al., ApJL, 628, L53 (2005) Strohmayer & Watts, ApJL, 632, L111 (2005) Watts & Strohmayer, ApJL, 637, 118 (2006) Strohmayer & Watts, astro-ph/0608463 Watts & Strohmayer, astro-ph/0608476 - Geoff referred to parallels with the interactions of the jets and disks in Blazars with the surroundings, which also produce internal shocks similar to models invoked for GRBs - Geoff also commented on the enormous amount of archival data available online nowadays from high-energy missions. Allowing local theorists and non-expert observers to use this data by collaborations with experts in the group is a key objective of these telecons! Logistics ctd., windup etc. - How to structure the conference? Conference reports would be great (e.g. some will attend the upcoming HEAD meeting; can report on the 13th). - Others to invite? Gravity wave community would definitely be interested. Qinghuan Luo & Don Melrose at USyd, Stefan Dieters at UTas. - Nanda Rea (SRON) visiting later this year. - Zdenka suggested a future session be dedicated to gamma-ray astronomy, to be held at a time which suits the Adelaide crowd. - A weekend meeting (similar to the ANITA workshop in September 2004; http://astronomy.swin.edu.au/anita/HEA) seems timely since there has been no comparable event since. Meeting concluded.