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e-EVN science projects (2006-2008)

e-EVN science projects (2006-2008). Zsolt Paragi (JIVE), for the EXPReS project. What will e-VLBI offer for us one day?. Several Gbps data rates/telescope, greatly increased sensitivity, “full” uv-coverage, flexibility…. What the e-EVN can do by the end of 2008:.

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e-EVN science projects (2006-2008)

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  1. e-EVN science projects (2006-2008) Zsolt Paragi (JIVE), for the EXPReS project

  2. What will e-VLBI offer for us one day? Several Gbps data rates/telescope, greatly increased sensitivity, “full” uv-coverage, flexibility… What the e-EVN can do by the end of 2008: • Open for users, regular observing sessions (10-12/year ) • Sensitivity and resolution comparable to disk recording • Already more flexibility for rapid response science! • Rapid feedback, you know if it works, you know what you observe… • … enables quick decision about more observations (VLBI or other) • Easy access, easy use – high level of PI support 7th e-VLBI Workshop, Shanghai

  3. Where are we now in capabilities… • Sensitivity and resolution in typical observations, 5 GHz • e-EVN in 2007, 256 Mbps: 50 uJy/beam, ~6 mas • e-EVN, 512 Mbps: 35 uJy/beam, ~6 mas • e-EVN in 2008, 512 Mbps, 17 Jy/beam, ~6 mas (10 Jy, ~1 mas • with Arecibo, Hh, Sh, Ur at lower data rates) • Full EVN (no Ar), 1024 Mbps, 12 Jy/beam, ~1 mas • VLBA, 512 Mbps, 30 Jy/beam, ~1 mas • VLBA+GBT, 512 Mbps, 12 Jy/beam 7th e-VLBI Workshop, Shanghai

  4. … and how far can we go • Sensitivity • Great 1 Gbps test results; 10 Gbps technology is available • Max. 1 Gbps with current EVN; 4 Gbps upgrade is investigated • Resolution/imaging • Sh tested in 2007; Ar, Hh, Ur 512 Mbps coming soon • Besides do not we do science (just few days year) with a more global array including Australian and Japanese telescopes??? • Flexibility • Limited e-EVN ToO is possible on previously unscheduled dates, but flexibility is still an issue 7th e-VLBI Workshop, Shanghai

  5. e-VLBI operations and test results - 2008 • Regular e-VLBI test observations in every six week (on average) • 24h time is pre-allocated for science observation during tests • Accepts normal and triggered proposals, more ToOs are supported • Science operations (so far) at 1.6 and 5 GHz, max. 512 Mbps with • Cm, Ef - new, Jb2, Mc, On, Tr, Wb; Mh - possible • Tests (more by Arpad, Harro, Paul): • With packet dropping near 1 Gbps  • Mixed data rate mode demonstrated • Ar, Hh, Sh, Ur can join science obs! • Four-continent fringes 7th e-VLBI Workshop, Shanghai

  6. The two newest members of the e-EVN in 2008 (AJPoD by Stefanie Muhle) 7th e-VLBI Workshop, Shanghai

  7. Science results from the ‘Oz-demo’ ATCA, Mopra and Parkes observations at 512 Mbps, correlated at JIVE. Target: the nearby supernova in the LMC, only visible from the South. One of the breathtaking Hubble Space Telescope images of SN1987A 7th e-VLBI Workshop, Shanghai

  8. And with VLBI… Various fits to the data to measure the size of the expanding remnant. Tingay et al., (in prep.) Highest resolution image of SN1987A so far (first VLBI!) – not bad for a three telescope array. Countours shows an earlier ATCA image. 7th e-VLBI Workshop, Shanghai

  9. e-EVN science projects in 2006/2007 • Cyg X-3, 20 Apr/18 May 2006, 128 Mbps, Tudose et al. • GRS1915+105, 20 Apr 2006, 128 Mbps, Rushton et al. • LSI +61.303, 256 Mbps, 26 Oct 2006, Perez-Torres et al. • Algol, 26 Oct/14 Dec 2006, 256 Mbps, Paragi et al. • Calibrators near M81, 14 Dec 2006, 256 Mbps, Brunthaler et al. • INTEGRAL microquasar candidates, 14 Dec 2006, Pandey et al. • “double header” run, 15 XRBs, 29 Jan 2007, Rushton & Spencer • Calibrators, 21 Feb 2007, 256 Mbps, Tudose et al. • J2020+3631 microquasar candidate, 28 Mar 2007, 256 Mbps, Martí et al. • Cyg X-3, 12-13 Jun 2007, 256 Mbps, Tudose et al. • Stellar maser search, 22-23 Aug 2007, 32 Mbps, Langevelde et al. • INTEGRAL source redo, 6-7 Sep 2007, 256 Mbps, Pandey et al. • Type Ib/c SN 2007gr, 6-7 Sep 2007, 256 Mbps, Paragi et al. 7th e-VLBI Workshop, Shanghai

  10. First refereed journal papers: GRS 1915+105: Rushton et al. (2007), MNRAS 374, L47 Cyg X-3: Tudose et al. (2007), MNRAS 375, L11 Cyg X-3 Aftermath of a huge outburst -first detection of polarisation on VLBI scales in a microquasar What PI’s really need is to be able to monitor these events in (1) closely spaced monitoring observations, (2) when they happen, not on fixed dates. 7th e-VLBI Workshop, Shanghai

  11. LSI 61+303 campaign: • Binary XRB system, also source of very energetic gamma rays; • What is the source of these? Earlier hypothesis: microquasar jet. • Recent VLBA observations (Mioduszewski et al.) suggest an • interacting pulsar wind source instead • MAGIC collaboration observations including e-EVN, VLBA, MERLIN, CHANDRA in October 2006 The MAGIC telescope and a view of its surroundings in La Palma. It is capable of detecting very high energy gamma rays. The telescope is operated by the MAGIC collaboration of 17 institutes since 2004. http://wwwmagic.mppmu.mpg.de/ 7th e-VLBI Workshop, Shanghai

  12. …and the results • no ultimate answer on the nature of the binary yet • radio and X-rays originate from a different population • of electrons, but • there is indication for temporal correlation between • X rays and gamma rays • Albert et al. (2008), Astrophys. J. (accepted), • astro-ph/0801.3150 7th e-VLBI Workshop, Shanghai

  13. IGR 17303-0601 results: INTEGRAL source, with candidate optical counterpart showing binary nature, and associated(?) radio source in NVSS. e-VLBI confirms compactness, but measured position is inconsistent with optical coords. Not associated, radio source is not from a microquasar jet – likely background AGN. M. Pandey, Z. Paragi, P. Durouchoux, H. Bignall, PoS(Dynamic2007)041 7th e-VLBI Workshop, Shanghai

  14. CHARA and e-VLBI observations of Algol Algol is one of the most famous variable stars, also known as beta Persei. It is very nearby, only 26 parsecs away, ideal for optical/radio interferometry studies. Algol is active from radio to the X-ray bands, besides the optical variations due to regular eclipses. Artist’s impression on the close binary system from the web. The K-subgiant is the source of radio activity. 7th e-VLBI Workshop, Shanghai

  15. The CHARA array The CHARA array is located at Mount Wilson in California, USA, and is operated by the Center for High Angular Resolution for Astronomy http://www.chara.gsu.edu/CHARA/ 7th e-VLBI Workshop, Shanghai

  16. CHARA results CHARA fringes before and after processing. Resulted visibility amplitudes vs. baseline length are shown below. Fitted orbital parameters to the data, found geometry of the system. Determined distance: 26.1±0.4 pc, Comparable or better accuracy than HIPPARCOS! Paragi et al., submitted to PoS (Manchester MRU proceedings) Csizmadia et al. (refereed paper in prep.) 7th e-VLBI Workshop, Shanghai

  17. Algol, 14 December 2006 e-EVN run: • Simultaneous optical photometry and e-EVN obs. • (5 GHz, 256 Mbps) during secondary minimum • Source flared – total intensity and circular polarization • variations consistent between WSRT and e-EVN data • Flare emission ~2 mas offset from the CP peak Dedicated observations of such flares will be challenging even for e-VLBI + • Detected proper motion during the • 10 hours run –fitted orbital parameters • of the AB close binary, but… 7th e-VLBI Workshop, Shanghai

  18. Supernovae: and old story with e-EVN Garrett et al. (2005) • SN2001em was discovered on 15 September 2001 in UGC11794 galaxy (Pepenkova 2001). • Redshift z~0.02 corresponding to a distance of 80~Mpc. • 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 7th e-VLBI Workshop, Shanghai

  19. SN 2007gr ToO observations • SN2007gr was discovered on 15 Aug 2007 • with KAIT (CBET 1034); identified as • Type Ib/c. • Distance is about 7.3 Mpc, 10x closer than SN 2001em was. • VLA discovers 610 microJy radio source • (Soderberg 2007) • e-EVN observations: Da, Jb2, On, Tr, Wb (256Mbps), at 6cm, on 2007 Sep 6-7 • Firm detection (5.6 ) of the supernova • within the VLA error box • Paragi et al. (2007), ATel #1215 7th e-VLBI Workshop, Shanghai

  20. The first ATel message from the e-EVN 7th e-VLBI Workshop, Shanghai

  21. A number of exploratory runs Supernovae in IC694, member of the famous Arp299 galaxy merger system. PI Perez-Torres. (MERLIN image from Antonis Polatidis) ... record breaking correlaton job! On 8-9 April 2008, the first real triggered observations: Cyg X-3 in an X-ray states change. Followed by a huge outburst and three ToO epochs, first e-EVN observations outside the fixed dates. e-VLBI flexibility: could not do it with disks because stations were short of them! Science projects in 2008 7th e-VLBI Workshop, Shanghai

  22. The Cyg X-3 puzzle; preliminary maps by the PI, Valeriu Tudose Cyg X-3 giant flare (preliminary) 7th e-VLBI Workshop, Shanghai

  23. Transients obviously, from quick turnaround mostly Surveys of a large sample of weak sources, detection not 100% guaranteed (but likely) 1) can follow up quickly the detected sources only, at other frequencies 2) big surveys not limited by recording media capacity Projects requiring dynamic scheduling Others???, e.g. support to VSOP-2 Survey, quick compactness check of highly variable sources (also in size!) before space VLBI observations? How could we best support X-ray and gamma missions, for example GLAST? What science would benefit from e-VLBI? J1427+3312, z=6.12 The highest redshift radio-detected quasar, with the EVN at 1.6 GHz - CSO at the edge of the visible Universe! (Frey et al. 2008) 7th e-VLBI Workshop, Shanghai

  24. e-MERLIN will be complementary in resolution to the e-EVN; short spacings LOFAR will be an exceptional instrument for finding new transients Wide FoV focal plane array considered for the WSRT - could also serve as a trigger instrument Synergy with other (e-)instruments GLAST www.gsfc.nasa.gov LOFAR (up) and DIGESTIF on the WSRT (left); from Astron web 7th e-VLBI Workshop, Shanghai

  25. As Steven pointed out yesterday, e-VLBI is technologial pathfinder to SKA. Specific developments in EXPReS definitely make the e-EVN an SKA pathfinder. But do not think just the technology! We are looking for new ways of doing VLBI research, especially in the area of transients, which could soon transform our field considerably. e-EVN matured a great deal during the first two years of EXPReS, now it is time to harvest the results. EXPReS eVSAG (e-VLBI Science Advisory Group) will address this within a few days. Finishing thoughts... 7th e-VLBI Workshop, Shanghai

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