Slide 1

PulSE Michael Kramer Chiang Mai- 28 June 2005 The double pulsar: Unique tests of Einsteins theory of general relativity EPTA The European Pulsar Timing Array Slide 2 PulSE Michael Kramer Chiang Mai- 28 June 2005 The double pulsar: Unique tests of Einsteins theory of general relativity The EPTA partners: University of Manchester, JBO, UK ASTRON, NL Max-Planck Insitut fur Radioastronomie, GER INAF Osservatorio Astonomico di Cagliari, IT Nancay Observatory, FR Slide 3 PulSE The EPTA Based on a long and fruitful collaboration Supported in the past (and future) by EU programmes (TMA, FP6) Unique feature of European astronomy: 4 (soon 5) 100-m class radio-telescopes: - Effelsberg (100m) - Westerbork (96m) - Nancay (92m) - Lovell (76m) - Sardinia (64m) All telescopes have active timing programs Different rate of observations, different observing frequencies Combine data sets to create dense multi-frequency sample 2005 Descartes Prize of The European Union Slide 4 PulSE The EPTA: Status Memorandum of Understanding (MoU) signed in January 2006 Nancay joint in October 2006, MoU signed in December 2006 Students at all observatories since September Constituting workshop in October in Paris/Nancay Second workshop in Cagliari in May 2007 Next workshop in Bad Honnef 14-16 January 08 Students will visit collaborating observatories Separate projects for each student with GW detection as joint goal Slide 5 PulSE The EPTA: How it works Coordinated source-lists and partly-coordinated observing sessions TOAs (later raw data) shared among partners Access for every partner to set-up WIKI page Library of common synthetic multi-frequency templates (excellent experience with double pulsar timing) Long-term goal: joint and identical European pulsar backend Open to international collaboration (sharing TOAs for joint goal) MoU with PPTA in preparation Hope to reach similar agreement with NANOGrav Slide 6 PulSE The EPTA: The people Axel Jessner, Kosmas Lazarides, (Anton Zensus) Vice-Stappers, Gemma Janssen Michael Kramer, Andrew Lyne, Ben Stappers, Mark Purver, (Liu Kuo), Chris Jordan Ismael Cognard, Gilles Theureau, Rob Ferdman, Gregory Desvignes Nichi DAmico, Andrea Possenti, A Student plus engineers at all observatories Problem: None of the non-students can do this full time so far There is hope: Rob Ferdman at Nancay, dedicated PDRA to be included in next JBCA pulsar rolling grant Slide 7 PulSE The EPTA: The observatories In addition to regular timing, planning to have simultaneous sessions at the same and different frequencies. 44% 70% 15% 60% Slide 8 PulSE The EPTA: A sample 0034-0534 4.9 4.5 0218-4232 8.0 14.4 0613-0200 2.6 1.4 5.6 0621+1002 7.5 6.0 10 1012+5307 1.4 2.9 1022+1001 0.7 2.1 1640+2224 4.1 3.1 1713+0747 0.85 0.5 0.6 1821-24 2.2 0.9 1855+09 2.0 2.5 (3.0) 1937+21 1.3 0.3 0.9 2145-0750 2.7 1.8 4.0 WSRT Effelsberg Nancay Results for uncleaned data WRST total, PUMA II continues to works as expected Soon improved hardware (PDFB3) at Effelsberg and Sardinia Slide 9 PulSE Combining data isnt easy but is useful Westerbork + Parkes: 1713+0747 Slide 10 PulSE Combining data isnt easy but is useful Westerbork + Parkes + Effelsberg: 1713+0747 Slide 11 PulSE Combining data isnt easy but is useful Effelsberg: 1855+09 Slide 12 PulSE Combining data isnt easy but is useful Effelsberg: 1713+0747: RMS 695ns 1855+09 Slide 13 PulSE Combining data isnt easy but is useful Effelsberg: 1713+0747: RMS 695ns 1855+09 Slide 14 PulSE Example of completed project: J1518+4904 GB WSRT Nancay JB EB Jannsen et al. (to be submitted) Slide 15 PulSE Example of completed project: J1518+4904 Jannsen et al. (to be submitted) Slide 16 PulSE Example of completed project: J1518+4904 Shapiro constraint Xdot constraint Total mass = 2.7183(7) M sun Jannsen et al. (to be submitted) Slide 17 PulSE Summary Total mass = 2.7183(7) M sun Great potential with already large data set covering ~10 years Progress is slow: - more difficult to clean/correct/check data retrospectively, but long time-baseline also helps - limited manpower available - no explicit funding available - inhomogeneous data sets initially difficult Advantages: - Inhomogeneous data sets: error checking! - Long multi-frequency data sets - Redundancy to mitigate for telescope/hardware failures Near future: - improved hardware - new 64-m dish with lots of observing time - Actually join EPTA-PPTA datasets