Onsala Space Observatory http://www.evlbi.org/ Present status and future directions of the EVN Michael Lindqvist, Onsala Space Observatory Zsolt Paragi, JIVE
Onsala Space Observatory
http://www.evlbi.org/
PresentstatusandfuturedirectionsoftheEVN
MichaelLindqvist,OnsalaSpaceObservatoryZsolt Paragi,JIVE
Onsala Space Observatory
http://www.evlbi.org/
ThanksTasso!
Onsala Space Observatory
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VLBIscience
• Radiojet&blackholephysics• Radiosourceevolution• Astrometry• Galacticandextra-galacticmasers• Gravitationallenses• Supernovaeandgamma-ray-burststudies• Nearbyanddistantstarburstgalaxies• Natureoffaintradiosourcepopulation• HIabsorptionstudiesinAGN• SpacescienceVLBI• Transients• SETI
Onsala Space Observatory
http://www.evlbi.org/
DescriptionoftheEVN• TheEuropeanVLBINetwork(EVN)wasformedin1980.Todayitincludes
15majorinstitutes,includingtheJointInstituteforVLBIERIC,JIVE
• JIVEoperatesEVNcorrelator.JIVEisalsoinvolvedinsupportingEVNusersandoperationsofEVNasafacility.JIVEhasofficiallybeenestablishedasanEuropeanResearchInfrastructureConsortium(ERIC).
• TheEVNoperatesan“opensky”policy
• NostandingcentralisedbudgetfortheEVN- distributedEuropeanfacility
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Thenetwork
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EVNande-VLBI
Fromtapereeltointercontinentallightpaths• Piecesfallingintoplacearound2003:
– IntroductionofMark5recordingsystem(gamechanger)byHaystackObservatory– Emergenceofhighbandwidthopticalfibrenetworks
• Thedevelopmentofe-VLBI hasbeenspearheadedbytheJIVE/EVN(EXPReS,Garrett)• Inthisway,theEVN/JIVEisarecognizedSKApathfinder
JIVE
e-VLBI
JIVEHotscience
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e-VLBI- rapidturn-around• e-VLBIhasmaderapidturn-aroundpossible
– X-ray,γ-raybinariesinflaringstates(includingnovae)
– AGNγ-rayoutbursts— locusofVHEemission– Otherhigh-energyflaring(e.g.,Crab)– OutburstsinMiravariables(spectral-line)– Just-explodedGRBs,SNe– Binaries(incl.novae,XRBs)atspecific
orbital/outburstphases– FRB– follow-upofGravitationalWaveevents
Onsala Space Observatory
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From triggersto (early)results
e-VLBI:DeliveringthemostsensitiveVLBIarrayinaflexibleway…
Onsala Space Observatory
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e-VLBI:DeliveringthemostsensitiveVLBIarrayinaflexibleway…
From triggersto (early)results
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EVN- currentstatus
• Callforproposals:3timesperyear:(February1,June1,October1)
• Wavebands:90,18,6,5,3.6,1.3,0.7cm
• MaximumAngularResolutioninmilliarcseconds:5mas(18cm),1.5mas(6cm)
• Notafulltimearray,theEVNobservesduring“sessions”:
– 3EVNdisksessions(3x3weeks)
– 10e-VLBIsessions(10x24hours)
– TargetofOpportunityandOut-of-Session
• Diskrecordingande-VLBIsimultaneously
• Automatedtriggere-VLBI
• MostdatacorrelatedatJIVE
• Collaborations:EVN+NRAO/GBO/LBO,EVN+RadioAstron,EVN+LBA
Onsala Space Observatory
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EnhancingEVNcapabilities
• Newtelescopesandcollaborations– e-MERLINwithalloutstationsat1Gbps(andbeyond)– KunMing,AfricanVLBINetwork(AVN),FAST,MeerKAT,TNRT– SKA
Onsala Space Observatory
http://www.evlbi.org/
EnhancingEVNcapabilities
• Nextgenerationreceivers,backends andrecordingsystems– DBBC3:Morebandwidth(2x4GHz)– RadioNet:BRoad BANDEVN,1.5– 15.5GHz– 100Gbpstechnologyrolledout– butnotallstationsaree-connected– …
• Newobservingmodes– Commensalsurveys:fasttransientsignals(<2s)inEVNdata(LOCATe)– Openforsuggestions!
Onsala Space Observatory
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Automatedgenerictriggers
• GoalInterrupt/triggeranewobservationwithin10minutes(e-VLBI)
• Why?ProbeanewtransientparameterspaceintheEVN
• (Almost)entirelyautomatedFromtrigger(e.g.viaVOEvent )toobservation&correlationPIneedstoworkwithJIVE
• Offeredfrom2015
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Exploitapotential’EVN-lite’
• Lesser-usedtelescopes
• Long-termmonitorprograms
• Wouldmakeautomatedtriggerreallyuseful
• Needpressurefromthecommunity
Onsala Space Observatory
http://www.evlbi.org/
Correlator- hardwareorsoftware?JIVEUniBoard Correlator(JUC)• Onceitworks,itgoesliketheclappers• Perfectfor“simple”operations• Notnearlyasflexible• Hard(er)todevelop/debug/modify/upgrade
firmware• 16stationson2availableUniBoards at
2Gbps
EVNSoftwareCorrelatoratJIVE(SFXC):• Fantasticallyflexible• “Easy”tomodify,improve,extend,
expand,upgrade• Hardwaregetscheaperastimegoesby• Definitelynotsuitedforheavylifting• 6-7stationsat2Gbps+3-4at1Gbps• Successfultestsat4Gbps
Onsala Space Observatory
http://www.evlbi.org/
EVNintheSKAera
• ThetwoinstrumentsarecomplementarybecausetheangularresolutionoftheEVNisbetter
• EVNalsoobservesatshorterwavelengthnotavailabletoSKA1
• Very-high-sensitivityVLBIobservationswillbepossibleusingSKA1-MIDactingasasinglephased-upelement
• InterestintheEVNwillincreasefurtherintheSKAeraastherewillbeincreasingdemandforfollow-upVLBIobservationsathighresolution
Onsala Space Observatory
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Onsala Space Observatory
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Mostimportant– theusers!
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InwhichwayshouldtheEVNdevelop?
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Supernova1993JinM81• SN1993Jisatextbookexamplewhereone
cantracethephysicalandstructuralevolutionofansupernova,anexplodingstar
• From1993ithasbeenthesubjectofintensestudies
Bartel etal.;Marcaide etal.
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ThedwarfnovaSSCygni• SSCyg isperhapstheprototypedwarfnova,the
outburstsresultfromchangesintherateatwhichmattermovesthroughthediskontothewhitedwarf
• UsingVLBAandtheEVN,Miller-Jonesetal.,(2013) wereabletoaccuratelymeasurethedistancetoSSCyg
• VLBIdataplacesSSCyg substantiallycloser,114±2pc,thanHSTdata,159±12pc
• ThenewdistancemeasurementhassolvedthepuzzleofSSCygni’s brightness,itfitsthetheoriesafterall
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TheRepeatingFastRadioBurstFRB121102asseenonmilliarcsecondangularscales
Onsala Space Observatory
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SETIexperimentwithEVN/VLBI
• Sofar,fewreportedVLBIprojects
• UsingtheLBA,Rampadarathetal.(2012)observedtheM-dwarfstarGliese581
• DemonstratedtheefficiencyofVLBIatdiscriminatingbetweenSETIsignalsandRFI
• MonitorpotentialhabitableplanetswithEVN-lite?
Onsala Space Observatory
http://www.evlbi.org/
Summary
• Developmentcancomeeitherbottom-up(newtechnologylookingforastronomicaluses)ortop-down- (definingastronomicalproblemsfirstandfindingtechnicalsolutionsafterward).EVNdoesboth.
• Continuouslybeingupgraded,newtelescopes,hardware,network,correlators,observingmodes
• ThefuturefortheEVNislookingbrightalsowhenweentertheSKAera
• EVN- formedin1980,stillreadyfortheunexpected!
Onsala Space Observatory
http://www.evlbi.org/
Thankyouforyourattention!Anyquestions?