OnthedetectabilityofBLLacobjectsbyIceCube

ChiaraRighi--------------------------------------------------UniversitàdegliStudidell’Insubria

INAF-OABrera

CollaboraConwith:F.Tavecchio,M.Landoni,D.GueLa

Overview

• High-energyNeutrinosdetectedbyIceCube

• Blazars

• BLLacobjectsasneutrinosourcecandidates

Discoveryofhigh-energyneutrinosbyIceCube

∼60eventssince2010.

3Whoproducetheseneutrinos?

Aartsen2016

Howtoobserveneutrinos

•  NeutrinointeracCons:

•  Atenergies>10GeVleptonsproduceCherenkovradiaCon.

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DifferentsignatureCascade(νe,νμ,ντ) Tracks(νμ)

ν

ν

μ

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CC&NC

North&South

CC

North

Searchingforsources

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Tracks(νμ)Cascade(νe,νμ)

Wewillconsideronlyνμtosearchpossiblesourcecandidates.

≈60events(cascade+tracks)from2010

IceCubeCollaboraCon(2014,2015a)

Blazars

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•  10%ofAGNareradio-loud

JET

Tavecchioetal.2014Tavecchioetal.2015Padovanietal.2016Resconietal.2016

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JetspoinCngatus:

Synchrotron InverseComptonLeptonicmodel

Hadronicmodel Synchrotron Photo-mesonproducConorsynchrotron(protons)

BulkLorenzfactorΓ≈10-20

Lobs=L’δ4whereδ=[Γ(1-βcosθv)]-1

OutshinesanyotherisotropicemissioncomponentassociatedtoAGN(disk,dust)ortothehostgalaxy.

Blazars

Dopplerfactor

Blazars

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FSRQ

BLLac • Lesspowerful• High-energypeakreachingintheTeVband• SynchrotronSelf-Compton

• Powerful• Powerful-rayemission• ExternalCompton

High-energyneutrinoproducCon

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PeVneutrinosareassociatedtoprotonswithofEp∼1016-17eVinteracCngwithUV/sowX-rayphotons.

RelaCvisCc

protons!!

High-energyneutrinoproducCon

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PeVneutrinosareassociatedtoprotonswithofEp∼1016-17eVinteracCngwithUV/sowX-rayphotons.

RelaCvisCc

protons!!

AreBlazarsgoodcanditates?

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BLLac!  Padovanietal.2016(spaCalcorrelaConwithγ-ray

BLLacsdetectedabove50GeV)!  Tavecchioetal.2014efficientneutrinoproducCon

FSRQ! PossiblecorrelaConbetweenoneneutrinoeventandagamma-rayflareofaFSRQobject(Kadleretal.2016).• MuraseandWaxman2016

TeVBLLacascandidate

•  Padovanietal.(2016)

•  Tavecchioetal.(2014)

High-emi~ngBLLac(HBL)objectsaspossibleneutrinoemi~ngcandidates

SEDofMkn421

Abdoetal.2011

TeVemiLer

Themodel

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Gamma-raysky(50GeV–2TeV) High-energyneutrinossky(>100TeV)

N.B:Onlyνμfromthenorthernhemisphere.

N.B:OnlyHBLobjectof2FHLcatalogue.

Aartsenetal.20161607.08006v1forthetotalneutrinoflux

Results

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EffecCveAreaofthedetector

Neutrinofluxofthesourceourmodel

16Righietal.2016

Results

17Righietal.2016

Results

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WithMonteCarlosimulaCon

Workinprogress

Awer7yearIceCubeshoulddetectMkn421.

Summary

•  IceCubeobseved≈60high-energyneutrinosabove100TeV•  SourcessCllunknown•  Blazars,andinparCcularHBL,aregoodcandidatestoproduce

high-energyneutrinos

•  ThescenarioforHBLobjectsisconsistentwithnodetecConbyIceCube

•  An“opCmisCc”esCmateoftheCmetoreach5sigmaforthetwobrightestHBLsourcesis7years.Weareclosetodetectthem?

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Thank you!

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ChargecurrentcrosssecCon

ALenuaConduetoEarthaveragemuonenergy-

lossrate

Neutrinofluxforeachsource

Gaisser(1990)

Spine-layermodel

Γs=15-20Γl=3-5

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Γl

Γs

p

Ghisellinietal.2005Tavecchio&Ghisellini2008,2014

TherelaCvemoConofthetwocomponentsleadstotheamplificaConoftheradiaConfieldofthelayerasobservedinthespinereferenceframe.

InthisscenariotheBLLacobjectsaregoodcandiatestoproduceneutrino.

ThisscenarioisnotgoodforFSRQsbecauseofthephotoninrunningtophoto-mesonreacConaremostlikelytheUVphotonofthebroadlineregion(BLR).Thisimpliedavery-highenergyofprotonandsoofneutrinos.

Workinprogress

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Murase&Waxman(2016)"constraintstocosmologicaldensity(lowerlimit)andluminosity(upperlimit)forcandidatesneutrinoemi~ngsourceclasses.WeresumethisworkbyapplyingitforHBLsources.

BLLac≠HBL

HBLhavealargerspacedensityandlowerluminosity.

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