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European VLBI Network Newsletter Number 47 May 2017 Contents Message from the Chairman of the EVN Board of Directors .............................................................................. 1 Call for the EVN Proposals .................................................................................................................................. 3 EVN Science Highlights: VLBI observations of four radio quasars at z>4: blazars or not? .................................. 8 JIVE UniBoard Correlator (JUC) ......................................................................................................................... 10 Upcoming Meetings .......................................................................................................................................... 10 IAU Symposium 336 Astrophysical Masers: Unlocking the Mysteries of the Universe. (4-8 Sept. 2017) ..... 10 47th Young European Radio Astronomers Conference (YERAC, 18-22 Sept. 2017) ..................................... 11 2017 European Radio Interferometry School (ERIS, 16-20 Oct. 2017) ......................................................... 11 _________ Edited by Antonis Polatidis, EVN Secretary (ASTRON, The Netherlands; [email protected]) Message from the Chairman of the EVN Board of Directors Dear Colleagues in the European VLBI Network, Dear Users of the EVN, The European VLBI Network (EVN) Consortium Board of Directors (CBD) met on 9 and 10 May 2017 in Torun (Poland). There were discussions on reports from the PC, the TOG, the correlators, JIVE, the stations, and partner organisations. The PC Chair reported a greater diversity in recent proposals with regard to the nature of the observing time requested. A working group of the CBD has been formed to discuss tailoring the mix of EVN observing options: issues to be considered included the balance between eVLBI and regular session time, and catering to large-scale, or possibly long-term proposals. Following an interesting presentation by W. Brisken, director of the LBO, the working group may consider further opportunities for Global VLBI. The CBD also discussed several rotations in the membership of the EVN PC. In order to increase the utility of the information in the EVN Archive, the CBD decided that the abstracts of accepted proposals will become publicly available once the first dataset resulting from a proposal is uploaded into the EVN Archive; this will be implemented starting with proposals submitted for the October 2017 Call for Proposals, and will be clearly announced in that call.

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European VLBI Network Newsletter

Number 47 May 2017

ContentsMessagefromtheChairmanoftheEVNBoardofDirectors..............................................................................1

CallfortheEVNProposals..................................................................................................................................3

EVNScienceHighlights:VLBIobservationsoffourradioquasarsatz>4:blazarsornot?..................................8

JIVEUniBoardCorrelator(JUC).........................................................................................................................10

UpcomingMeetings..........................................................................................................................................10

IAUSymposium336AstrophysicalMasers:UnlockingtheMysteriesoftheUniverse.(4-8Sept.2017).....10

47thYoungEuropeanRadioAstronomersConference(YERAC,18-22Sept.2017).....................................11

2017EuropeanRadioInterferometrySchool(ERIS,16-20Oct.2017).........................................................11

_________EditedbyAntonisPolatidis,EVNSecretary(ASTRON,TheNetherlands;[email protected])

MessagefromtheChairmanoftheEVNBoardofDirectors

DearColleaguesintheEuropeanVLBINetwork,DearUsersoftheEVN,

TheEuropeanVLBINetwork(EVN)ConsortiumBoardofDirectors(CBD)meton9and10May2017inTorun(Poland).TherewerediscussionsonreportsfromthePC,theTOG,thecorrelators,JIVE,thestations,andpartnerorganisations.ThePCChairreportedagreaterdiversityinrecentproposalswithregardtothenatureoftheobservingtimerequested.AworkinggroupoftheCBDhasbeenformedtodiscusstailoringthemixofEVNobservingoptions:issuestobeconsideredincludedthebalancebetweeneVLBIandregularsessiontime,andcateringtolarge-scale,orpossiblylong-termproposals.FollowinganinterestingpresentationbyW.Brisken,directoroftheLBO,theworkinggroupmayconsiderfurtheropportunitiesforGlobalVLBI.TheCBDalsodiscussedseveralrotationsinthemembershipoftheEVNPC.InordertoincreasetheutilityoftheinformationintheEVNArchive,theCBDdecidedthattheabstractsofacceptedproposalswillbecomepubliclyavailableoncethefirstdatasetresultingfromaproposalisuploadedintotheEVNArchive;thiswillbeimplementedstartingwithproposalssubmittedfortheOctober2017CallforProposals,andwillbeclearlyannouncedinthatcall.

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Figure1:EVNCBDmeetingparticipantsandtheirhostsinfrontofthe32mtelescopeatTorunRadioObservatory

TheCBDalsodiscussedtheTOGreport.ItwasnotedinparticularthataverysubstantialsubsetoftheEVNstationsnowhasthecapabilityfor2Gbpsobserving,anddevelopmentcontinues.TheCBDhasthereforeconfirmeditsaimtobuildupintheshorttermenoughrecordingcapacitytoestablish2Gbpsasthestandardrecordedbitrateforcontinuumprojects.TheTOGhasbeenaskedtoreporttheinvestmentthateachstationwouldhavetomaketorealizethisaim.T.VenturipresentedtheprocessandtimelineforthecreationofanEVNFutureVisiondocument,whichwillbeanoverviewofthescientificstrengthsoftheEVNaswemoveintothenextdecade,andcanalsoservetoguideprioritiesforfurthertechnologysteps(forwhichthereissomuchpotential,e.g.leadingonfromcurrentdevelopmentprojectssupportedthroughRadioNetandJumpingJIVE,whichkickedoffinJanuaryandFebruary).BySeptember2018acompletedraftVisiondocumentwillbereadytobepresentedtotheUsers’Meetingatthe14thEVNSymposium.Refinementstothatdraftwillbemadeintheyearfollowing.AsIamnearingtheendofmytermasCBDChairon1July,itismyprivilegeindeedtoreportthatJohnConwayhasbeenappointedasthenextCBDChair–wealllookforwardtoworkingwithhiminthatrole!IamalsoveryhappytoreportthatRafaelBachillerwillbethenextvice-ChairoftheCBD.Lookingbackonmyterm,IseethatasteadilycontinuingdevelopmentoftheEVN.Dataratesareincreasing,asmentionedalready,bothforeVLBIandrecordedVLBI.Capabilities,andtheflexibilityofobservingandprocessingwerefurtherenhanced,andmanyotherissueshavebeensuccessfullytackledbytheTOG.Ahighlightforme,andIamsureformycolleaguesaswell,wastheentry,inOctober2016,oftheVentspilsInternationalRadioAstronomyCentre(VIRAC)withitsIrbeneobservatoryasanewfullmemberoftheEVN!ManycolleaguesintheEVNhaveprovidedsupportinonewayoranothertomakepossiblethisadditiontoourfamily,whichisfurthermoreatributetothededicationandcompetenceoftheVIRACstaffinaccomplishingatrulymajoroverhauloftheir16-meterand32-meterSoviet-vintageradiotelescopes.ThenewavailabilityoftheKunming40mtelescopeasanaffiliatedstation(advertisedforthefirsttimeinthe1June2017CallforProposals)isanotherverywelcomestep,showingthatthegrowthofthecapabilitiesoftheEVNiscertaintocontinue.OfcoursealloftheseEVNdevelopmentsarecrownedbyseeingthescienceresultscomeout.InrecentCBDmeetingsIhaveaskedthattheEVNPCChairpubliclypresentsthetraditionalupdateonnewsciencehighlights,duringalunchorteatalktowhichallstaffofthehostinstituteareinvited.ThecapabilitiesofVLBIwerealsoshowcasedrecentlyatothermeetingswithabroadaudience,suchastheworkshopon“Nanoradiansonthesky:VLBIacrosstheMediterraneanandbeyond”duringthe2016EuropeanWeekofAstronomyandSpaceScience(EWASS).Ahighlightwasofcoursethepressattentionthatwasattractedby

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thefirstlocalizationofaFastRadioBurst(FFRB),inwhichtheEVNplayedaprominentrole,presentedattheJanuary2017AmericanAstronomicalSociety'smeetinginGrapevine,Texas.ButtomethebestrecentbroadoverviewoftheexcellentstateofEVNsciencewasthe13thEVNSymposium(2016);thanksagaintotheIAAcolleaguesforhostingit!Allthemorereason,therefore,tolookforwardtothedatesnowdecidedforthe14thEVNSymposium,tobeheldinGranada,Spain:October8-11,2018.ThenextmeetingoftheEVNConsortiumBoardofDirectorswillbeheldinNovember2017,inOnsala,Sweden.Meanwhile,the1stJune2017deadlineforCallforProposalsisapproaching.TheEVNProgrammeCommitteewillnextmeetonJune27,2017,inBolognatoreviewtheproposals.Inclosing:weallknowthattheEVNowesitssuccessestoalargeanddedicatedgroupofpeoplewhoarebasedbothattheEVNobservatoriesandatJIVE(itwassatisfyingthatlastyearHuibJanvanLangeveldeandIwereabletosignanSLAonthemanywaysinwhichtheJIV-ERICsupportstheEVN).ButIamsurenobodywillobjectwhenIsingleoutforpersonalthankstheofficersoftheEVN,PCChairMichaelLindqvist,TOGChairPablodeVicente,andEVNSchedulerAlastairGunn,fortheirmanyinteractionswithmeduringmytermasChair,forhavingtodealwithmysometimesdifficultorcumbersomequestions,butmostlyfortheirexcellentandtirelessefforts,whichareabsolutelyrequiredtokeeptheEVNrunning.IamalsogratefultoEVNSecretaryAntonisPolatidisforhissupportinmanyways,includingtheeditingofthisNewsletter.RenéVermeulen,Chairman,EVNConsortiumBoardofDirectors

CallfortheEVNProposalsEuropeanVLBINetwork

CallforProposalsDeadline1stJune2017

Thistextisalsoavailableonthewebat

http://www.chalmers.se/en/centres/oso/radio-astronomy/vlbi/Documents/EVN_CfP.txtObservingproposalsareinvitedfortheEVN,aVLBInetworkofradiotelescopesspreadthroughoutEuropeandbeyond,operatedbyaninternationalconsortiumofinstitutes(http://www.evlbi.org/).Theobservationsmaybeconductedwithdiskrecording(standardEVN)orinreal-time(e-VLBI).TheEVNfacilityisopentoallastronomers.UseoftheNetworkbyastronomersnotspecialisedintheVLBItechniqueisencouraged.TheJointInstituteforVLBIERIC(JIVE)canprovidesupportandadviceonproposalpreparation,scheduling,correlationandanalysis.SeeEVNUserSupportathttp://www.jive.eu.FutureStandardEVNObservingSessions(diskrecording)2017Session3Oct19-Nov0918/21cm,6cm...2018Session1Feb22-Mar1518/21cm,6cm...2018Session2May24-Jun1418/21cm,6cm...

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2018Session3Oct18-Nov0818/21cm,6cm...

Proposalsreceivedby1stJune2017willbeconsideredforschedulinginSession3,2017orlater.Finalisationoftheplannedobservingwavelengthswilldependonproposalpressure.

Futuree-VLBIObservingSessions(real-timecorrelation)

2017Sep19-Sep20(startat13UTC)18/21cm,6cm,5cmor1.3cm2017Oct10-Oct11(startat13UTC)18/21cm,6cm,5cmor1.3cm2017Nov14-Nov15(startat13UTC)18/21cm,6cm,5cmor1.3cm2017Dec14-Dec15(startat13UTC)18/21cm,6cm,5cmor1.3cm

Pleaseconsultthee-VLBIwebpageathttp://www.evlbi.org/evlbi/e-vlbi_status.htmltocheckforpossibleupdates,andfortheavailablearray.Successfulproposalswithane-VLBIcomponentsubmittedbytheFebruary1deadlinewillbeconsideredforschedulingintheabovee-VLBIsessionsstartingfromSeptember19,2017.

Notethatonlyonewavelengthwillberunineache-VLBIsession,selectedbasedonproposalpriorities.

Seehttp://www.jive.eu/jivewiki/doku.php?id=evn:guidelinesfordetailsconcerningthee-VLBIobservationclassesandobservingmodes.NewFeaturesfortheNextStandardEVNande-VLBISessionsTheKunming40mtelescopeisanaffiliatedEVNstationsituatedonPhoenixMountain,about10kmeastofthecityofKunming,China.ThetelescopemayberequestedonabesteffortsbasisforEVNdiskrecordingobservationsat13,6,5and3.6cmwavelengths.e-VLBIat2Gbpsisavailableat6cmand1.3cmatasubsetoftheEVNtelescopes.Theremainingtelescopeswillobserveat1Gbps(mixedmodeobservation).Thecurrentstatusisgivenhere:

http://www.evlbi.org/evlbi/e-vlbi_status.html

Diskrecordingat2Gbpsisavailableat6cm,3.6cm,1.3cmand0.7cmatasubsetoftheEVNtelescopes.Theremainingtelescopeswillrecordat1Gbps(mixedmodeobservation).Thecurrentstatusisgivenhere:

https://deki.mpifr-bonn.mpg.de/Working_Groups/EVN_TOG/2Gbps

Useofthisdatarateshouldbeclearlyjustifiedandlimitedtoprojectsthatreallyneedit.

Pleaseconsulthttp://www.evlbi.org/evlbi/e-vlbi_status.htmlandtheEVNUserGuidehttp://www.evlbi.org/user_guide/user_guide.htmlforupdatesonthecurrentEVNande-VLBIarray,availabilityofdifferentstationsperobservingbandandforthedatesofthee-VLBIobservingsessions.GlobalVLBIProposals

Globalproposalscanbeproposedupto2GbpsincludingVLBA,GBTandtheJVLA.

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Somemodesmayrequiredifferentbandwidthchannelsatdifferenttelescopes;correlationatJIVEcanhandlethis.

JIVEsupportstaffwillworkwithSocorrotoassistyouduringtheschedulingprocessofsuchobservations.

GlobalobservationswillbecorrelatedattheSFXCcorrelatoratJIVE(default)orattheDiFXcorrelatorinBonnorattheDiFXcorrelatorinSocorro(ifappropriatejustificationisgivenintheproposal).RadioAstronObservationsProposalsrequestingtheEVNasgroundarraysupportorcorrelationatJIVEforRadioAstronAO5observationsintheperiod:19October2017to30June2018,maybesubmittedatthisdeadline.LargeEVNProjects

Mostproposalsrequest12-48hrsobservingtime.TheEVNProgramCommittee(PC)alsoencourageslargerprojects(>48hrs);thesewillbesubjecttomoredetailedscrutiny,andtheEVNPCmay,insomecases,attachconditionsonthereleaseofthedata.AvailabilityofEVNAntennasTheSRTwillbeofflineforatleasttheentire2017andVLBIoperationsareexpectedtorestartatsometimein2018.Exactdatewillbecommunicatedatalaterstagewhenclosertoresumeoperations.

TheIrbene32mtelescopeisanewEVNstationlocated30kmnorthofVentspils,Latvia.ThetelescopemayberequestedforEVNdiskrecordingobservationsat18(singlepol.,RCP,uncooledreceiver),6,5and3.6cmwavelengths.

TheWSRTwillbeparticipatingwithasingletelescope,equippedwithdualcircularpolarizationreceivers.Thefrequencycoveragewillremainthesame.ProposerswhowishtousetheEVNCalculator,shouldselect"W1"insteadof"Wb".

Tm65isthe65mtelescopeatTianma,about6kmawayfromthe25mSeshantelescope(Sh).The2-letterabbreviationforTm65telescopeisT6.Bothofthesetelescopescanobserveat18,13,6,5,3.6,and3.6/13cm.Tm65canalsoobserveat21cm.Tm65isthedefaulttelescope;ShwillbeusediftheTm65isnotavailableforsomereason.Ifyouselectboth,youshouldalsodiscussthemotivationfortheveryshortbaselineintheproposal.Integrationofe-MERLINTelescopesintotheEVNIntegrationofe-MERLINoutstationantennasintotheEVNisnowpossiblefollowingrecentsoftwareupgradesonthee-MERLINcorrelatoratJodrellBankonasharedriskbasis.EVNexperimentscannowincludemultiplee-MERLINoutstationantennasinadditiontoanantennaatJodrellBank.Thetotalrecordedbandwidthfortheoutstationswillbelimitedto1Gbpsbutcanbedividedbetween1,2or4e-MERLINantennas.PIsofproposalsshouldindicateinthescientificjustificationwhiche-MERLINantennastheywishtorecord.ThesedatawillthenbeavailableforcorrelationwithallotherEVNstationsinmixedmode,

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providingafullyintegratedadditionalsetofshortspacingEVNdataforthefirsttime.Forexample,withine-MERLIN,thebaselinecoveragefromJb+Da,Kn,De,andCmwouldspanseparationsof11to220km.

Proposerscanalternativelystillrequestafullbandwidthe-MERLINobservationforhighsensitivitylowersurfacebrightnessimagingwherethee-MERLINtelescopesarecorrelatedatJBO.Thiscontemporaneousmodewillbeofferedasafallbacktosimultaneousobservations

Foranytechnicalqueriescontact:[email protected]

TheKoreanVLBINetwork(KVN)isanAssociateMemberoftheEVN.KVNtelescopesmayberequestedforEVNobservationsat1.3cmand7mmwavelengths.FormoredetailsregardingtheKVN,see:http://radio.kasi.re.kr/kvn/main_kvn.phpUseofAustralianVLBINetworkAntennasSomeAustralianLongBaselineArray(LBA)timewillbemadeavailableforsimultaneousschedulingwiththeEVN,thusenablingthepossibilityofjointLBA/EVNobservations.TheeasternmoststationsoftheEVNareinasimilarlongituderangetotheLBAtelescopes,andforsourcesinequatorialregions,baselinestowesternEuropeanstationsarealsoachievable.JointLBAtimeislikelytobeheavilyoversubscribed,andauthorsarerequestedtonotewhethertheyarepreparedtoacceptschedulingwithoutLBAantennasbeingpresent.

AnyproposalsforjointEVN+LBAobservationssubmittedtotheEVNbyits1June2017deadlineshouldalsobesubmittedtotheLBAbytheir(provisional)15December2017deadlineandwillfirstbeeligibleforschedulinginEVNSession1/2018.

FormoredetailsregardingproposingtimeontheLBA,see:http://www.atnf.csiro.au/observers/apply/avail.html&http://www.atnf.csiro.au/vlbi/index.html

EVN+LBAobservationsshouldbepossibleatallprincipalEVNwavebandsfrom21cmto1.3cm.:See:(http://www.evlbi.org/user_guide/freq_cov.html)andhttp://www.evlbi.org/user_guide/EVNstatus.txt.OutofSessionObservingOut-of-Sessionobservingtime(uptoamaximumof144hours/year)isnowavailabletoallproposals(diskrecordingore-VLBI).

ProposalsrequestingOut-of-Sessionobservingtimemustprovidefullscientific(andtechnicalifappropriate)justificationastowhyobservationsmustbemadeoutsidestandardsessions.

Out-of-Sessionobservingblocksshouldbenolessthan12hoursinduration(althoughindividualobservationscanbeshorter),andoccurnomorethan10timesperyear.

Proposalsshouldspecifywhichdates/GSTrangesarebeingrequestedandindicatetheminimumrequirementintermsofnumbersoftelescopes(andanyparticulartelescopes).

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ProposalswillonlybeconsideredfordatesoccurringaftertheregularEVNsessionthatfollowsEVNproposalreview.

Observationsrequiringmuchshorterleadtimesshouldbesubmittedas"Target-of-Opportunity"(ToO)proposals.Jointobservationswithotherfacilities

Forjointobservationswithotherfacilities,e.g.,EVN+XMM,separateproposalsshouldbesubmittedtotheEVNandtotheotherfacility.SuchproposalswillbeconsideredbytheEVNPConacase-by-casebasis.

HowtoSubmitAllEVNandGlobalproposals(exceptToOandshort-observationproposals,seehttp://www.jive.eu/jivewiki/doku.php?id=evn:guidelines)mustbesubmittedusingtheNorthStaron-lineproposalsubmissiontool.GlobalproposalswillbeforwardedtoNRAOautomaticallyandshouldnotbesubmittedtoNRAOseparately.

Newproposersshouldregisterathttp://proposal.jive.eu.

Proposalsmustincludethefollowingsections:1.Science&technicaljustification2.Figures,tablesandreferences(optional)

ThesesectionsshallbesubmittedasasinglePDFdocument.Thetotallengthofthisdocumentislimitedto4pages(A4orUSLetterformat),withafontsizenosmallerthan11points.Proposersarefreetoadjustthelengthofthevariousproposalsectionswithinthisoveralllengthlimit.

Thestronglyrecommendedbreakdownis2pagesfortheScience&technicaljustificationand2pagesforFigures,tablesandreferences.

Figuresandtablesmaybeinterleavedwiththesciencejustification,sothate.g.figuresappearclosetothelocationinthetextwherereferencesaremadetothem.

WhenspecifyingrequestedantennasfromtheLBA,pleasespecify'LBA'underthe"other"rowinthetelescope-selectionbox-thisselectsallthatareavailableforjointobservations.

Thedeadlineforsubmissionis23:59:59UTCon1stJune2017.AdditionalinformationFurtherinformationonEVN,EVN+MERLIN,GlobalVLBIande-VLBIobservations,andguidelinesforproposalsubmissionareavailableat:http://www.jive.eu/jivewiki/doku.php?id=evn:guidelinesTheEVNUserGuide(http://www.evlbi.org/user_guide/user_guide.html)describesthenetworkandprovidesgeneralinformationonitscapabilities.

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Thecurrentantennacapabilitiescanbefoundinthestatustables.ForthestandardEVNseehttp://www.evlbi.org/user_guide/EVNstatus.txt

Forthee-EVNarrayseehttp://www.evlbi.org/evlbi/e-vlbi_status.html

TheOn-lineVLBIcatalogue(http://db.ira.inaf.it/evn)listssourcesobservedbytheEVNandGlobalVLBI.

Aselectionofrecenthighlightsispresentedhere:http://www.jive.eu/jivewiki/doku.php?id=evn:evn_science

AselectionofrecentrefereedEVNpublicationsispresentedhere:http://www.jive.eu/jivewiki/doku.php?id=evn:evn_publications

MichaelLindqvist,OnsalaSpaceObservatory,EVNPCChairman

EVNScienceHighlights:VLBIobservationsoffourradioquasarsatz>4:blazarsornot?Blazarsareactivegalacticnuclei(AGN)whoserelativisticjetspointnearlytothelineofsight.Theircompactradiostructurecanbeimagedwithverylongbaselineinterferometry(VLBI)onparsecscales.BlazarsatextremelyhighredshiftsprovideauniqueinsightintotheAGNphenomenaintheearlyUniverse.Fourradiosourcesatredshiftz>4wereobservedwiththeEuropeanVLBINetwork(EVN)ine-VLBImodeat1.7and5GHzin2015and2016(projectcode:EC054).ThetargetswerepreviouslyclassifiedasblazarcandidatesbasedonX-rayobservations.VLBIimagingwasusedtoconfirmtheblazarnatureofthesesources.Theresultswerepartlyexpected-andpartlysurprising.Dual-frequencyEVNdatashowthatthesourceJ2134-0419(z=4.35)hasacompactone-sidedcore-jetstructureextendedto~10-masangularscale.Thecorebrightnesstemperatureindicatesarelativisticallybeamedjet,asexpectedfromablazar.

Figure2:Dual-frequencyEVNimagesofJ2134-0419,agenuineblazarwithaone-sidedjetandaDoppler-boostedcompactcore(C).ThecolourscaleindicatestheintensityinmJy/beam.

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Anothertarget,J0839+5112(z=4.39)hasacompactradiostructuretypicalofquasars.Thereisevidenceforfluxdensityvariabilityanditsradiocorehasaflatspectrum.However,thelessextremebrightnesstemperaturederivedfromtheEVNdatasuggestthatitsemissionisnotDoppler-boosted.Therealsurprisecamefromtheremainingtwotargets,J1420+1205(z=4.03)andJ2220+0025(z=4.21).BothofthemshowradiopropertiestotallyunexpectedfromradioAGNwithsmall-inclinationjet.TheirradioemissionextendstoarcsecscalesandtheDopplerfactorsofthecentralcomponentsarewellbelowunity.Theirweaknuclearradioemissionisincompatiblewiththeblazarscenario.Thesetwosourcesratherresembledouble-lobedradioAGNwithlargeinclinationwithrespecttothelineofsight.Thisisincontrastwiththeblazar-typemodelingoftheirmultibandspectralenergydistribution(SED).

Figure3:Theleftpanelshowsthe1.4-GHzVLAA-configurationimageofJ2220+0025(Hodgeetal.2011,AJ,142,3).ThetwocrossesindicatethepositionsofourweakEVN-detectedcomponentsat1.7GHz.Thecentralcomponent(labeledasC)isalsoseenat5GHzwiththeEVN(thetaperedimageisontheright)andiscoincidentwiththeopticalquasarposition.ThecolourscaleindicatestheintensityinmJy/beam.

ItispossiblethatotherX-rayemitting,highlyradio-loudAGNalsomimicthetypicalblazarproperties,yettheybelongtodifferenttypesofsources.ThismaycontributetotheapparentlylargerfractionofblazarsfoundintheearlyUniverse.Sensitiveimagingatintermediateresolutionwithe-MERLINhasrecentlybeenproposedtomaptheextendedstructureinJ1420+1205,J2220+0025,andanothersimilarradiosourceknownfromtheliterature,topossiblyrevealbothofthesymmetriclobesandthelarge-scalejets.TheseEVNresultscallfortherefinementofthebroad-bandSEDmodeling,poseaninterestingquestionaboutthephysicaloriginofthehigh-energyemissioninJ1420+1205andJ2220+0025,anddrawtheattentiontotheimportanceofVLBIimagingobservationsforreliablyclassifyingblazarsathighredshifts.Publishedat:Hong-MinCao,SándorFrey,KrisztinaÉ.Gabányi,ZsoltParagi,JunYang,DávidCseh,Xiao-YuHong,TaoAn:VLBIobservationsoffourradioquasarsatz>4:blazarsornot?(2017,MNRAS,467,950)http://dx.doi.org/10.1093/mnras/stx160

SandorFrey,KonkolyObservatory,HungarianAcademyofSciences

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JIVEUniBoardCorrelator(JUC)TheJIVEUniboardCorrelator(JUC)isanFPGA-basedcorrelatorthatcancorrelatetwopolarizationsoffoursubbandswithabandwidthofupto64MHzfor32stationsonasingleboard.Thecorrelationengineisnowwell-testedandcommissioningisprogressing.

TheUniboardcorrelator'slowpowerconsumptionandhighdatathroughputmakesitaveryattractivecandidateforeVLBIoperationsamongothermodes.Testsofthisfunctionalityareunderway.Asingle2.5-minscanofJ1955+5131fromarecentEVNobservationat6cmwithsevenstations:Effelsberg,Medicina,Noto,Onsala,Tianma,Zelenchukskaya,andBadarywascorrelatedwithboththeproductionSFXCsoftwarecorrelatorandtheJUCFPGAcorrelator,witheightsubbandsof1024channelseach.Theoutputsignalsaftercorrelationagreewithin1%(Figure4).

Figure4:Thefinalimagesobtainedfromthisscanwiththetwocorrelations.Itcanbeclearlyseenthatbothimagesareidentical,showingacompactsourcewithapeakbrightnessof5.16mJy/beamandanoisermslevelof0.39mJy/beam.Thesynthesizedbeamis3.9x0.86mas,andcontoursstartat3timesthenoiselevelwithincrementsofsquarerootof2

ArpadSzomoru,JointInstituteforVLBIERIC

UpcomingMeetings

IAUSymposium336AstrophysicalMasers:UnlockingtheMysteriesoftheUniverse.(4-8Sept.2017)RegistrationisstillopenfortheInternationalAstronomicalUnionSymposium336onAstrophysicalMaserswhichwillbeheldonSeptember4-8,2017inCagliari(Sardinia),Italy.

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Onthepastfiveyearstherehasbeenanexplosionofworkonmasers,especiallyrelatedtothecosmicdistancescale,thestructureoftheMilkyWay,andthemassesof(AGN)blackholes.Specifictopicsforthissymposiumwillinclude:-TheStructureoftheMilkyWay-LocalGroupCosmology-TheCosmicDistanceScaleandtheHubbleConstant-GalaxyKinematicsandBlackHoleMasses-TheFormationofMassiveStars-PulsationandOutflowsinEvolvedStars-Theoryofmasersandmasersources

Detailsareavailableontheconferencewebsite:http://iaus336.oa-cagliari.inaf.it

47thYoungEuropeanRadioAstronomersConference(YERAC,18-22Sept.2017)TheYoungEuropeanRadioAstronomersConference(YERAC)for2017,willbehostedbytheIstitutodiRadioastronomiainBolognaonSeptember18-22,2017.TheIstitutodiRadioastronomiahostedtheYERACthreetimesinthepast:in1972,1980and1996.

YERAChasbeenheldalmosteveryyearsince1968,hostedbythevariousEuropeanRadioAstronomicalInstitutes.ThepurposeofYERACisforundergraduate,graduateandyoungpost-doctoralstudentsinradioastronomyfromalloverEuropetomeeteachotherandpresenttheirwork.'Europe'includesanycountryfromRussiaintheEasttoPortugalinthewest,plusaffiliatesoftheEuropeanVLBINetwork,RadioNetorothercurrentbodies.Duetoitsnature,YERACcoversallaspectsofradioastronomy,fromtheSunouttothecosmicmicrowavebackground,fromstarsandplanetstothemostdistantgalaxies,usingsingledishandinterferometrictechniques,modelsandtheoreticalwork.

ParticipationinYERACisbynominationonly.Amaximumofabout50participantswillbeaccepted.DirectorsofradioastronomicalinstitutesandUniversityDepartmentsareinvitedtosendonestudentandinformtheorganizationoftheYERACassoonaspossible.

Furtherinformationcanisgivenattheschool’swebsite:http://indico.ira.inaf.it/event/4/.

M.Bondi&T.Venturi,IRAfortheYERAC2017organisingcommittee

2017EuropeanRadioInterferometrySchool(ERIS,16-20Oct.2017)

TheSeventhEuropeanRadioInterferometrySchool(ERIS)willtakeplaceinDwingeloo(TheNetherlands)duringtheweekof16-20October2017.

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ERISwillprovideaweekoflecturesandtutorialsonhowtoachievescientificresultsfromradiointerferometry.Thetopicscoveredbythelectures/tutorialswillinclude:

•Calibrationandimagingofcontinuum,spectralline,andpolarisationdata;•Low-freq.(LOFARdomain),high-freq.(ALMA/IRAMdomain),andVLBI-interferometry;•Extractinginformationfromthedataandinterpretingtheresults;•Choosingthemostsuitablearrayandobservingplanforyourproject.

Participantsareexpectedtobringtheirownlaptops,equippedwithAIPSandCASApre-installed.Exampleswillbedrawnfromm-,cm-andmm-waveinstrumentssuchasLOFAR,JVLA,EVN,e-MERLINandALMA.Furtherinformationcanbefoundattheschoolwebsite,www.astron.nl/eris2017FortheERIS2017SOC:J.McKean(RuG/ASTRON)&H.J.vanLangevelde(JointInstituteforVLBIERIC)