Breaking News
Shigeru Yoshida
ICEHAP - Chiba university

Lu Lu
1

The Cosmic Neutrinos
Production Mechanisms“On-source” n

TeV - PeVpp  p  np

gp  p  n

pphotopion production“GZK” cosmogenic nn

EeV
CMB

100EeV p

gp  p  n
14

Realtime Multi-Messenger
South Pole

< 3 minutes time lag

Northern Hemisphere
GCN-TAN16

IceCube Event Topology
Track

Cascade (shower)n

e+Xn
me
Angularresolution
Angular resolution
m CCCC~15degree~ 0.5 degreenx NC
 x + X x=e, m, tnt CC t (only at ultra-high energies)n messengers for follow-up ToO
observations

19IceCube Realtime Analysis Chainmuon multiplet for Gamma-ray/Optical follow-up
TeV
PeV

veto-based
HESE

muon neutrino sensitive
good angular resolutions
large background chance

TeVHigh cosmic n purity samples.
Launched in 2016!

PeV

EeV

all neutrino flavor sensitivehigh chance of real cosmic neutrino signals
angular resolutions so-so

EHE (Ultra-High Energies)
TeV

The breakthrough event
detected in this channel

EeV

PeV

EeV

all neutrino flavor sensitivehigh chance of real cosmic neutrino signals
good angular resolutions
signal flux highly uncertain

20

And the story began here
SMS noticepinged my (non-smart) cellphone

5:55 am, Saturday, September 23, JST
the greatest wakeup call I’ve ever had in Saturday morning

21

Numbers on IceCube 170922A
Identified by the EHE realtime stream
Run 130033 Evt 50579430
Date (UT):2017-09-22 20:54:30.436263
NPE:5785.94156
EHE linefit zenith 97.5

Revised zenith 95.7

RA: 77.43 DEC: 5.72 (J2000)

Provided by Claudio in the slack channel
22Event selections for EHE real time stream
Relaxed cuts on NPE-cos(zenith) plane for track-like EHE L3
c2 EHE trackfit < 80

Atmospheric BG“GZK “ n search
Real time nE-2 signal“GZK “ n search
Real time n23

IceCube 170922A
NPE 5,786 cos(zenith) -0.13

Atmospheric BG“GZK “ n search
Real time nE-2 signal“GZK “ n search
Real time n24

IceCube 170922A
NPE 5,786 cos(zenith) -0.13
right on the “sweat spot” signalness : 56.5 %E-2 signal
Atmospheric BG“GZK “ n search
Real time n“GZK “ n search
Real time n25

n detection effective area
𝑁 = 𝑇 න 𝑑Ω න 𝑑𝐸𝜈 𝜙𝜈 𝐸𝜈 𝐴𝜈 𝐸𝜈
# of events

timesolid angle

n fluxn effective area

Zenith bin of this n event

26

Neutrino Energy ?
Log(n Energy [GeV])

Initial estimate reported in the GCN: 120 TeV
profilen Energy Vs NPE (E-2.5)

Log(NPE)27

Neutrino Energy ?
Energy deposit estimated : 21.6 TeV

nm energy pdf at the earth surface

200TeV~ 7.5PeV

Log(NPE)28

Summary of the follow-up observations

And many more!

30

and this is what happenedng

31

Fermi Blazar TXS 0506+56
Right on top of IceCube 170922A
image madeby Masaaki Hayashida(Fermi)

32Fermi Blazar TXS 0506+56

Redshift unknown (0.15<z<1.6 (0.58))
categorized as ISP-BL Lac by Fermi(but the classification does not mean
we understand the type of this blazar)

33

The source images in multi-wavelength bands
radio

optical

x-ray

g-ray

50

We are on the road to checkmate a cosmic ray origin
chessJapanese “Shogi”

51

TeVPeVEeV

No Blazars as major sources
Blazar stacking analysis

Search for a cumulative n excess from 862 2LAC blazars

52Model dependent constraints on Blazars
TeV

PeV

EeV

IceCube Collaboration
ApJ 835 no.1 45 (2017)

TeV

nm only

PeV

EeV

IceCube Collaboration
PRL 117 241101 (2016)

all flavor sum53

Global Ultra-High Energy (UHE) Diffuse fluxes
The (yet-unknown) UHE cosmic ray (UHECR) sources are also the origin of IceCube TeV n?

IceTopEnergy flux

UHECRs

IceCube n ~ UHECRs

IceCube n

Is this just a coincidence?
Auger/TA59

UHECR-IceCube n Unified Model
The (yet-unknown) UHECR sources are also the origin of IceCube TeV n?

A genetic analytical model
UHECRs• Optical Depth 0.1• SFR-like evolution
Can be consistent with UHECR dataand n UL at higher energies

taking the formula from
Yoshida & Takami PRD 2014
Yoshida & Ishihara PRD 2012

60

UHECR-IceCube n Unified Model
The (yet-unknown) UHECR sources are also the origin of IceCube TeV n?

A genetic analytical modelUHECRs• Optical Depth 0.1• FSRQ-like evolution
Inconsistent withn UL at higher energies

taking the formula fromYoshida & Takami PRD 2014
Yoshida & Ishihara PRD 201261

Tracing history ofthe particle emissions with n flux
color : emission rate of ultra-high energy particles
rare

Intensity gets higher
if the emission is more
active in the pastnbecause n beams are
penetrating overcosmological distances

frequent

PresentRedshift (z)Past

Hopkins and Beacom, Astrophys. J. 651 142 (2006)

The cosmological evolution
Many indications that the past wasmore active.

Star formation rate
The spectral emission rater(z) ~ (1+z)mm= 0 : No evolution
62

TeVPeVEeV

The Constraints on evolution (emission history)of UHE cosmic ray sources
IceCube collaboration
Phys.Rev.Lett.117 241101(2016)

UHECR sourceis cosmologically
LESS evolved

Any sources with evolution
compatible or stronger thanstar formation rate are disfavoredr ~ (1+z)m0<z<zmax
FRII (FSRQs)
excluded

GRBs
allowed63

n flux at 100 TeVUHECR-IceCube n Unified Model
prediction fromthe unified model
constraints
from IceCube data fit

UHECRsThere are not many astronomicalobjects to meet these criteria
Optical depth> 0.01 if soft spectrumOptical depth~ 1 if hard spectrum
evolution weaker or compatible to SFRUHECR p spectrum

E-a64

UHECR-IceCube n Unified Model
Energetics requirements
Source luminosity with SFR-like evolution

E-2.2
E>10 EeV~4x1044 erg/Mpc3 yr

E-2.5~2x1044 erg/Mpc3 yr

extrapolate

E>10 PeV~2x1048 erg/Mpc3 yr
c.f. GRB Lg ~ 1044 erg/Mpc3 yr~6x1048 erg/Mpc3 yr

FSRQ Lg ~ 1046 erg/Mpc3 yr65

UHECR-IceCube n Unified Model
genetic requirements to UHECR sources
cosmological evolution compatible or weaker than star formation rate
IceCube bounds on GZK nFermi extra-galactic diffuse g-ray boundoptical depth t >~ 0.01 if E-2.6, t>0.1 if E-2.3 or harder
IceCube TeV-PeV n flux

c.f. GRB internal shock t~0.1, afterglow O(10-3) , BL Lac O(10-6)

Energy luminosity O(1048) erg/Mpc3 yr @ E>10 PeV
extrapolated from UHECR luminosity

BL Lac, GRB internal shocks, FSRQs all unlikely66

A major class of (UHE) cosmic ray sources isyet unknown

The solution
IceCube-Gen267

IceCube-Gen2
the staging strategy
IceCube-Gen2 Phase1
towards precise measurementsof ice’s optical characteristics

68

Improving the angular resolutions of n-induced
shower events for multi-messenger astronomy
The present – 15 degree error

Yes we can! 4 degree error

With better understandingsof C light scattering69

D-Egg detectors map out Ice
D-Egg schematics

D-Egg prototypes

70

IceCube Event Topology
Track

Cascade (shower)

n
e+
Xn
me
Angularresolution
Angular resolution
m CCCC~ 4 degree~ 0.5 degreenx  x + X
nt CC t (only at ultra-high energies)NCn messengers for follow-up ToO
observations

x=e, m, t

n new messengers for follow-up ToO
observations

71