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Present and future e-VLBI / EVN2015 science

Present and future e-VLBI / EVN2015 science. Zsolt Paragi, JIVE. The European VLBI Network. What are we doing not so good at the moment: No real frequency agility Limited observing time Little support for ToOs Slow science turnaround time (from proposal to paper)

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Present and future e-VLBI / EVN2015 science

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  1. Present and future e-VLBI / EVN2015 science Zsolt Paragi, JIVE

  2. The European VLBI Network • What are we doing not so good at the moment: • No real frequency agility • Limited observing time • Little support for ToOs • Slow science turnaround time (from proposal to paper) • Although most of these problems are not directly related to e-VLBI, • all of these are addressed today in the framework of e-VLBI developments. • The EVN2015 has to be a real-time array with great frequency coverage and • sensitivity, and should operate throughout the whole year. And these tapes • below will be gone long time before that! http://www.evlbi.org/ http://www.jive.nl/ Present and future e-VLBI... EVN2015 science

  3. The end of the tape era • Tape recording had limited performance (parity • errors), and • limited data rate (256 Mbps; 512 Mbps with • two write heads). • Tapes were expensive • Tape playback units were not easy to maintain • Disk based recording systems were developed at • Haystack (Mark5A) and Metsahovi Radio • Observatory (PC EVN) • And it worked! • The EVN is fully disk operational (Mark5A) • since early 2004 • Cheaper, off the shelf technology, perfect • recording; data rate up to 1 Gbps • http://www.haystack.edu/tech/vlbi/mark5/ Present and future e-VLBI... EVN2015 science

  4. Disks+ftp VLBI: reliability! • Disk recording is better quality, but it • also provides a way to quickly check • telescope performance: ftp tests • 2-4s data at 256 Mbps  64-128 MB files, • may be transferred through the Internet! • Data processed by a software correlator • developed in NICT, Japan • Since late 2004 there are regular ftp tests • during EVN sessions. • The software correlator runs on a PC cluster • Feedback to telescopes used to take at least • a week, now it is a matter of minutes • OK, let us see what else can we improve… Present and future e-VLBI... EVN2015 science

  5. VLBI observations timeline 1-2 weeks 2-3 months 2-3 months Select your source Write an observing proposal EVN PC makes a decision EVN scheduler provides a date    … another 2-3 months well, why would you hurry? Observe with VLBI Data correlation Data processing Publishing results    THIS MUST CHANGE! Present and future e-VLBI... EVN2015 science

  6. Target of Opportunity projects An example: the huge flare of SGR1806-20 • SGR1806-20 is a soft gamma-ray repeater a • neutron star with very strong magnetic fields, • a magnetar • Produced the greatest explosion witnessed by • humans in our Galaxy, on 27 December 2004 • Observations with various instruments, also • VLBI (with the VLBA array) • Could not image reliably because of lack of • known calibrator in the vicinity of the target! • Is there a way to do these projects more efficiently? • Is there a way to get the data and analyze them • quickly??? Fender et al. (2005), MNRAS 367, L6 Present and future e-VLBI... EVN2015 science

  7. What is EXPReS? • EXPReS = Express Production Real-time e-VLBI Service • Three year project, started March 2006, funded by the European Commission (DG-INFSO), Sixth Framework Programme, Contract #026642 • Objective: to create a distributed, large-scale astronomical instrument of continental and inter-continental dimensions • Means: high-speed communication networks operating in real-time and connecting some of the largest and most sensitive radio telescopes on the planet http://www.expres-eu.org/ Present and future e-VLBI... EVN2015 science

  8. WesterborkNetherlands OnsalaSweden ? 1Gb/s 10Gb/s ? ? ? ? 2.5Gb/s 155Mb/s 1Gb/s JIVE TorunPoland 1Gb/s Jodrell BankUK Cambridge UK e-MERLIN MedicinaItaly Telescopes connections (early 2007) Soon available: Effelsberg, Yebes 40m, Shanghai … Present and future e-VLBI... EVN2015 science

  9. e-VLBI activities in 2006/2007 • There are regular e-VLBI test observations in every six week (on average) • Normal operations at 256 Mbps (Cm, Jb2, Mc, On, Tr, Wb) • Fringes to several telescopes at 512 Mbps, most recently to Mc • 24h time is pre-allocated for science observation during each e-VLBI test • Observing proposals may be submitted two weeks before the advertised date • Science projects observed in 2006/ early 2007: • Cyg X-3, 20 Apr/18 May, 128 Mbps, Tudose et al. • GRS1915, 20 Apr, 128 Mbps, Rushton et al. • LSI +61.303, 256 Mbps, 26 Oct, Perez-Torres et al. • Algol, 26 Oct/14 Dec, 256 Mbps, Paragi et al. • Calibrators near M81, 14 Dec, 256 Mbps, Brunthaler et al. • INTEGRAL microquasar candidates, 14 Dec, Pandey et al. • 16 XRBs adaptive run, 29/30 Jan, Spencer et al. • Calibrators, 21 Feb, Fender et al. Present and future e-VLBI... EVN2015 science

  10. First refereed journal papers: Rushton et al. (2007), MNRAS 374, L47 Tudose et al. (2007), MNRAS… very soon Cyg X-3 Present and future e-VLBI... EVN2015 science

  11. LSI 61+303 preliminary results: Gamma-detected XRB candidate; Recent VLBA observations (Mioduszewski et al.) suggest interacting pulsar wind… e-EVN, MERLIN, CHANDRA Observations on 26 October 2006 Perez-Torres et al. (in prep.) Present and future e-VLBI... EVN2015 science

  12. Algol preliminary results: 26 October 2006 Csizmadia et al. (in prep.) Present and future e-VLBI... EVN2015 science

  13. 512 Mbps e-VLBI run 1/2 February 2007 (Cm),Jb2,On,Mc,Wb And Ef, Sh, Yb … coming: We are almost there!!! Present and future e-VLBI... EVN2015 science

  14. e-VLBI challenges • We are already very good in quick science turnaround: on the fly • data processing/pipelining is possible! • At 512 Mbs and with Effelsberg, Shanghai and other new telescopes, • we will also be very good in sensitivity and resolution (in 2007/2008) • BUT • We are poor with immediate good calibration • The current system is not suitable for real ToOs • We have to be able to produce high dynamic range maps of sources • varying on timescales of hours (=>EVN2015) • We must be able to change schedule on the fly to be able to observe • e.g. new transients with poor coordinates (=>EVN2015) Present and future e-VLBI... EVN2015 science

  15. Example: the Algol miniflare (14 Dec 2006) Variable flux, position and structure within hours! Csizmadia et al. (in prep.) Present and future e-VLBI... EVN2015 science

  16. Westerbork  e-EVN as a unique instrument • Westerbork Synthesis Array data may help in calibration (amplitude, linear • and circular polarization) • May help to confirm detection/non-detection of weak targets • Could be used as a ‘built-in’ alert instrument for the e-EVN • Wb can help improving coordinates of new transients… • …with adaptive scheduling, this could be immediately used for • the VLBI array • Not to mention the additional information on the very large-scale • structure (which we normally waste when we do not reduce Wb data • along with the EVN) • Will Westerbork be still around in 2015??? Present and future e-VLBI... EVN2015 science

  17. The e-EVN as an alert instrument? • Because we are not good in responding ToOs, but good in providing quick • results, can we turn around the logic? • Initially could monitor known transient sources (e.g. microquasars like • GRS1915+105) in a snapshot mode during the e-VLBI tests, regularly. • In case of a flare, report to the community, providing 0-epoch maps! • (not possible when a ToO VLBI run follows a single dish trigger) • Easily accessible for the whole astronomical community, ready maps from • the EVN archive (all public!) • With more sensitivity and dynamic scheduling, may continue this with • new X-ray transients or gamma bursts • How shall we select these key science targets? • Can we contribute to X-ray and gamma ray missions like GLAST? • Have invested a lot of money in e-VLBI, now let us invest a great deal of observing time! Present and future e-VLBI... EVN2015 science

  18. EVN2015 science I. Microquasars • Besides the present known radio-jet XRBs, a much larger fraction of the X-ray binaries will be detected by EVN2015. • Initial phases of flare evolution / jet proper motion in the first 100AU scales is not known. • Observation of mas-scale jet structural changes just before and during the early stages of a flare is necessary to understand better disk-jet coupling. • A change in Lorentz factor is predicted – how could we observe that? • Can we detect circular polarization at sub-mJy levels? Jet composition? • Is there an outflow or jet/ISM interaction region roughly perpendicular to the jet in all microquasars (like in SS433)? • What is the difference between the NS and the BH microquasar outflows? • Is there an underlying high Lorentz-factor jet in all microquasars? Present and future e-VLBI... EVN2015 science

  19. EVN2015 science I. Microquasars Paragi et al. 1999 New A.R. 43, 553 • So, what is happening to the core-jets during an outburst? Present and future e-VLBI... EVN2015 science

  20. EVN2015 science II. Other radio active binaries • Late-type stars show magnetic activity, a great stellar population to be studied by EVN2015. • At VLBI resolution one could resolve the magnetosphere of nearby spotted stars, and image the stellar spots in the radio directly! • Radio flaring Algol and RS CVn sources could be easily observed (on the fly selection of active targets) • What is the relation of the flares to magnetic activity or mass-exchange in these binaries? For example in Algol, one could resolve the Roche-lobe and even the stellar disks with the EVN. • Are these sources producing collimated outflows? Present and future e-VLBI... EVN2015 science

  21. EVN2015 science III. Gamma bursts • Is there prompt radio emission? LOFAR will do it at low frequencies. Can we constrain cm-wavelength emission (models do not predict, but…)? • Will the EVN2015 (or earlier) be able to observe the prompt burst? • Theories/observations predict a jet break up days after the burst, with sudden drop of the Lorentz-factor; needs high frequency (≥22 GHz) very sensitive VLBI observations to study proper motion. These are far too faint for cm wavelength studies with space-VLBI. • What is the relation between SNIb/c and gamma bursts? • Can we observe off-axis GRBs in the radio? Present and future e-VLBI... EVN2015 science

  22. An old story: the first e-VLBI science result (continuum) • SN2001em was discovered on 15 September 2001 in UGC11794 galaxy (Pepenkova 2001). • Filippenko and Chornok (2001) classified it as type Ib/c, most likely Ic. • Exceptional radio and X-ray luminosities • (off axis GRB, developing late radio emission • due to jet break?), • Not quite a 1 mJy radio source • EVN observations: Cm, Jb2, On, Tr, Wb (128Mbps), +Arecibo 300m (64 Mbps) • at 18cm, on 2005 Mar 11 • Tentative detection (4.5 ) of the first real faint target with e-VLBI • Paragi et al. (2005), MSAIt 76, 570 • Needs better resolution and sensitivity! • => EVN2015 Present and future e-VLBI... EVN2015 science

  23. EVN2015 science IV. Extragalactic XRBs, ULXs, IMBHs • EVN2015 will have the sensitivity to study microquasars in nearby galaxies • Ultra-luminous X-ray sources: all super-Eddington accreting XRBs with geometric beaming of X-rays, or are there intermediate mass black holes as well? • The superior sensitivity of EVN2015 will be able to constrain black hole masses in ULXs, and will provide resolution to image their (sub-) pc-scale structure. More resolution together with VSOP-2! • Again, the e-EVN could monitor ULXs and alert community in case of a radio detection. • With wide field of view imaging, could monitor whole (or part of) nearby galaxies, looking for radio transients; note that e-MERLIN and e-VLA could do this as well, but we would be late with follow up VLBI observations! Present and future e-VLBI... EVN2015 science

  24. EVN2015 science IV., ULXs… The minimum detectable black hole mass Present and future e-VLBI... EVN2015 science

  25. EVN2015 science IV., ULXs… The minimum detectable black hole mass Present and future e-VLBI... EVN2015 science

  26. EVN2015 science IV., ULXs… Predicted ULX radio flux densities Present and future e-VLBI... EVN2015 science

  27. EVN2015 science IV., ULXs… Predicted ULX radio flux densities Present and future e-VLBI... EVN2015 science

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