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Examples of Examples of ScienceScience

• Generic fluxes associated Generic fluxes associated with cosmic rayswith cosmic rays

• Astrophysics: gamma ray Astrophysics: gamma ray burstsbursts

• Particle physics: cold dark Particle physics: cold dark matter searchmatter search

Nature’s Particle Nature’s Particle AcceleratorsAccelerators• Electromagnetic Electromagnetic

Processes:Processes:– Synchrotron EmissionSynchrotron Emission

• EE (E (Eee/m/meecc22))33 B B

– Inverse Compton ScatteringInverse Compton Scattering

• EEff ~ (E ~ (Eee/m/meecc22))22 E Eii

– Bremmstrahlung Bremmstrahlung

• EE ~ 0.5 E ~ 0.5 Eee

• Hadronic CascadesHadronic Cascades– p + p + ±± + +oo +… +… e e ±± + + + + + +

……

– p + p p + p ±± + +oo +… +… e e ±± + + + + + +……

Radio Optical X-ray GeV TeV

E2 dN/dEorF

High Energy Gamma-Ray AstrophysicsHigh Energy Gamma-Ray AstrophysicsTypical Multiwavelength SpectrumTypical Multiwavelength Spectrum

from High Energy from High Energy -ray source-ray source

[ Energy

Emitted]

[ Photon Energy]

Spinning Neutron Star Fills Nebula with Energetic ElectronsSpinning Neutron Star Fills Nebula with Energetic Electrons

=> Synchrotron Radiation and Inverse Compton Scattering=> Synchrotron Radiation and Inverse Compton Scattering

Active Galactic NucleiActive Galactic Nuclei

•Massive Black Hole Accelerates Jet of Particles to Relativistic Velocities=> Synchrotron Emission and Inverse Compton and/or Proton Cascades

Challenge I: Acceleration

R

B

eBREBRvR

BR

ccV p

/

1~

1 2

LdE /dt {B2

84R2dR}/dt 4R2 B2

8v

1

2E p

e

2

c

shock velocity

L 22

E p,20

2 1045 erg/s

(V = e = v/c

=boosted energy from cosmic accelerator

Energy in extra-galactic cosmic rays ~

3x1037 erg/s or 1044 erg/yr per (Mpc)3

3x1039 erg/s per galaxy 3x1044 erg/s per active galaxy

2x1052 erg per gamma ray burst

1 TeV = 1.6 erg

brightest known sources match IF equal energy in protons and electrons

(photons)

• AGN (steady): ~ few requires L>1047 erg/s

Few, brightest AGN• GRBs (transient):~ 300 requires L>1051 erg/s

Average L~1052 erg/s

equal energy in neutrinos?

some definitions

flux F = dN/dE (particles cm-2 s-1)

fluency f = E dN/dE (erg cm-2 s-1)

luminosity L = f x 4d2 (erg s-1)

Point Sources

P 10 4 E

100TeV

, 1 for E 100TeV,

0.5 o.w.

event # 1 event f

10 11erg/cm2s

E

100TeV

1

AT

1km2yr

Signal:

Background (atmos. ’s):

3 events f

10 12erg/cm2s

deg

-1 E

300TeV

0.8AT

1km2yr

1/ 2

For 10 -- 1000 TeV:

serg/cm10 2-1

km

112Af

f t /100s 310 5 Akm 2 1 erg/cm2

Cosmological sources:

erg10s100/

erg/s10cm10 1-

km

5.52

-1

km

4628

2

2

AtL

ALd

Most Powerful Cosmological sources:

AGN (Steady)

GRBs (~100s transient)

f 10 11erg/cm2s

25erg/cm10F

1. ~1 km2 detector2. Same UHE CR “suspects”

Challenge II: Propagation (GZK)

• >1020eV proton: E<100 Mpc

• Bright AGN (Radio galaxies)- too far

• GRBs Does the spectrum support GZK?

Model• Fly’s Eye fit for Galactic heavy (<1019eV):

JG~E-3.50

• X-Galactic protons: Generation spectrum (shock acceleration):

Generation rate:

Redshift evolution ~ SFR

;2,/ nddn nppp

[EW 95]

;yrMpc

erg103

344

0

eV10

eV10

21

19

zp

ppp d

ndd

R

Model vs. DataX-G Model: 2.1n yr;erg/Mpc100.3 344 R

]Bahcall & EW 03[

Ruled out7

5

Conclusions are Robust 2.0n yr;erg/Mpc105.3 344 R

CR Conclusions• Yakutsk, Fly’s Eye, HiRes: Consistent with

XG protons: + GZK

Robust; Consistent with GRB model predictions

• AGASA (25% of total exposure): Consistent below 1020eV Excess above 1020eV: 2.2+/-0.8 8 observed New source/ New physics/ 25% energy Local inhomogeneity over-estimate

• Stay tuned for Auger (Hybrid)

yrMpc

erg108.0

3442

p

pp dE

ndE

??

diffuse flux

flux = velocity x density flux = c/4 x density, for isotropic flux

<-- in energy density

E dN/dE dE = c/4x E

E dN/dE = A E cm-2 s-1 sr-1 (= -1)

diffuse backgroundSignal:

Background (atmos. ’s):

yrkm1TeV100srsGeV/cm101 #event

2

1

29

2 AT

2 510 8GeV/cm2s sr

Waxman-Bahcall bound

~ 1km2 detector --> 50 events/yr

2/1

2

8.0

28

2

yrkm1TeV300srsGeV/cm103

ATN

n Flux Bound• Observed JCR(>1019eV)

• For Sources with p < 1:

• Strongest know z evolution (QSO, SFR): collect ’s beyond GZK

srscm

GeV105

4 28

H22

zzcr t

dE

ndE

cE

[EW & Bahcall 99, Bahcall & EW 01]

yrerg/Mpc10 344

0

2 z

cr

dE

ndE

3)1( 3 Zcr zn

p for known sources

p

n

+ e+

e-

62

2 1042

2'

'

mm

mm

mm

p

e

pe

pp

eV102102TeV1 173 pp

Antares

Nemo

Neutrinos from GRB: an Neutrinos from GRB: an exampleexample

111m releasedinside 102km

(opaque)

Fireball ’s 100MeV

’s produces byelectron synchrotron

Relativistic shock = 102 - 103

electron - protonacceleration

22

3344

Gamma-ray Bursts M on ~1 Solar Mass BH

Relativistic Outflow

e- acceleration in Collisionless shocks

e- Synchrotron MeV ’s L~1052erg/s

~300

[Meszaros, ARA&A 02]

GammaGammaRayRayBurstBurst

• Photons and protonsPhotons and protonscoexist in internalcoexist in internalshocksshocks

• External shocksExternal shocks

1997BATSE: 1991- May 2000

1969

NUMEROLOGYNUMEROLOGYLL = 10 = 105252 erg/s erg/s

RR00 = 100 km = 100 km

EE = 1 MeV = 1 MeV

t = 1-10 msect = 1-10 msec= 300= 300ttHH = 10 = 101010 years years

dE/dt = 4x10dE/dt = 4x104444 erg Mpc erg Mpc-3-3yryr-1-1

PPdetecteddetected = 10 = 10-6-6 E E0.80.8 (in TeV) (in TeV)

pp = 10 = 10-28-28cm2 for p+cm2 for p+n+n+< x< xp p > = 0.2> = 0.2

GRB1FRAMESFRAMES

Fireball FrameFireball Frame Observer FrameObserver Frame

~ 10~ 1022 - 10 - 1033

E = E = E' ~ 1 MeV E' ~ 1 MeVR = R = R' R'dd

R = cR = ct = Rt = R00 with R with R00 = R' (t = 0) = R' (t = 0)observed 1 msecobserved 1 msec

RR

RRR'R'

ccvv

grb kinematicsgrb kinematics• R0 100 km• cos = v/c

= [1- ]-1/2v2__c2

102 - 103

t = = (R - Rcos)R__ c

1_c

R__ c

R__2c

v__ c

v2__c2( 1 - )(1- )=•tobs

•Eobs E

R__2c

1__2

R

v

c~-

~-

~-

~-~-

GRB3

Pion (neutrino) production whenPion (neutrino) production whenprotons and photons coexistprotons and photons coexist

pp n n++ neutrinosneutrinos

nn00 gamma raysgamma rays

E'E'pp > > mm22

- m - m22pp__________________

4E'4E'EEpp > 1.4 x 10 > 1.4 x 1044 TeV TeV

EE = 1/4 < = 1/4 < xxp p > E> Epp 1/20 E 1/20 Ep p 0.7 PeV 0.7 PeV~~__ ~~__

Fraction of GRB energy converted Fraction of GRB energy converted into pion (neutrino) productioninto pion (neutrino) production

f f = = x x p p

15%15%

-1-1pp = n = nppee synchro/IComptonsynchro/ICompton ((LL))

pp pionspions (L(LCRCR))

R'R'______

pp

~~__

GRB4

fireballfireball

GRB2GRB2 Photon Density in the FireballPhoton Density in the Fireball

nn = = = = U'U'______E'E' E'E'______

LLt/t/____________44R'R'22R'R'

R' = R' = 22cctt

R' = R' = cctt

note: for note: for = 1 (no fireball) optical depth = 1 (no fireball) optical depth of of photons isphotons is

optopt = = R = = R00nnThTh ~ 10 ~ 101515

RR00____ ThTh

UU______EE

cc____44

1 1 ______ EE

dEdE____dtdt

GRB 5GRB 5

= = = = ((1/21/2 f f t tHH ))

charged charged only only

NNeventsevents = P = Psurvived survived PPdetected detected

20 km20 km -2 -2 yr yr -1 -1

LLCRCR LL

~~__

~~__

Neutrino flux from GRB fireballsNeutrino flux from GRB fireballs

cc____44

GRB 6GRB 6

NUMEROLOGYNUMEROLOGY

LL = 10 = 105252 erg/s erg/s

RR00 = 100 km = 100 km

EE = 1 MeV = 1 MeV

t = 1-10 msect = 1-10 msec = 300= 300

<x<xp -> p -> > = 1/5> = 1/5

pp = 10 = 10-28-28cmcm22

ttHH = 10 = 101010 years years

dE/dt = 4x10dE/dt = 4x104444 erg Mpc erg Mpc-3-3yryr-1-1

PPdetecteddetected = 10 = 10-6-6 E E0.80.8 (in TeV) (in TeV)

Search for HE Search for HE from GRB from GRB

Off source

GRB search bin

GRB Position

1 hour 1 hour16 s

BKG - off time BKG - off timeon time

GRB burst

Correlations Correlations to GRBto GRB

Correlations Correlations to GRBto GRB

Off source

GRB search bin

GRB Position

1 hour 1 hour16 s

BKG - off time BKG - off timeon time

GRB burst

88 BATSE bursts in 199788 BATSE bursts in 1997

Background cuts can beloosened considerably high signal efficiency

Combined Combined data give data give sensitivitysensitivity ~ prediction!~ prediction!

Marriage of Astronomy and PhysicsMarriage of Astronomy and Physics

• AstronomyAstronomy: new window on the Universe!: new window on the Universe! “ “You can see a lot by looking”You can see a lot by looking”• PhysicsPhysics::

search for dark mattersearch for dark matter

search for topological defects and cosmological remnantssearch for topological defects and cosmological remnantssearch for monopolessearch for monopolesmeasure the high-energy neutrino cross section measure the high-energy neutrino cross section

(TeV-scale gravity?)(TeV-scale gravity?)cosmic ray physics: 150 atmospheric nus/daycosmic ray physics: 150 atmospheric nus/day

array with EeV sensitivityarray with EeV sensitivitytest special and general relativity with new precisiontest special and general relativity with new precision

Relic density – simple approachRelic density – simple approach

Decoupling occurs whenDecoupling occurs when

< H< H

We haveWe have annv n

neq g

mT

2

3 / 2

e m / T

H(T ) 1.66g*1/ 2 T 2

mPlanck

H Tf m

20

h2 310 27 cm3s 1

annv

annv annv WIMP 1

The MSSM – generalThe MSSM – general

The Lightest Supersymmetric Particle (LSP)

Usually the neutralino. IfR-parity is conserved, it is

stable.

The Neutralino –

Gaugino fraction

1. Select MSSM parameters

2. Calculate masses, etc

3. Check accelerator constraints

4. Calculate relic density

5. 0.05 < h2 < 0.5 ?

6. Calculate fluxes, rates,...

Calculation done with˜ 1

0 N11˜ B N12

˜ W 3 N13˜ H 1

0 N14˜ H 2

0

Zg N11

2 N12

2

http://www.physto.se/~edsjo/darksusy/

LEP

h

2 < 0

.025

h 2 > 1

Low sampling

The mThe m-Z-Zgg parameter space parameter space

HiggsinosHiggsinos

MixedMixed

GauginosGauginos

WIMP search strategiesWIMP search strategies

• Direct detectionDirect detection

• Indirect detection:Indirect detection:–– neutrinos from the Earth/Sunneutrinos from the Earth/Sun–– antiprotons from the galactic haloantiprotons from the galactic halo–– positrons from the galactic halopositrons from the galactic halo–– gamma rays from the galactic halogamma rays from the galactic halo–– gamma rays from external galaxies/halosgamma rays from external galaxies/halos–– synchrotron radiation from the galactic center /synchrotron radiation from the galactic center /

galaxy clustersgalaxy clusters–– ......

• Direct detectionDirect detection

• Indirect detection:Indirect detection:–– neutrinos from the Earth/Sunneutrinos from the Earth/Sun–– antiprotons from the galactic haloantiprotons from the galactic halo–– positrons from the galactic halopositrons from the galactic halo–– gamma rays from the galactic halogamma rays from the galactic halo–– gamma rays from external galaxies/halosgamma rays from external galaxies/halos–– synchrotron radiation from the galactic center /synchrotron radiation from the galactic center /

galaxy clustersgalaxy clusters–– ......

Direct detection - general Direct detection - general principlesprinciples

• WIMP + nucleus WIMP + nucleus

• Measure the nuclear recoil energy

• Suppress backgrounds enough to be sensitive to a signal, or...

• Search for an annual modulation due to the Earth’s motion around the Sun

EdelweissEdelweissJune 2002June 2002

Most likely DAMApoint. Excluded at 99.8% CL

Direct detection – current limitsDirect detection – current limitsSpin-independent scatteringSpin-independent scattering Spin-dependent scatteringSpin-dependent scattering

Direct detection experiments have started exploring the MSSM parameter space!

Neutralino capture and annihilationNeutralino capture and annihilation

Sun

Earth

Detector

Freese, ’86; Krauss, Srednicki & Wilczek, ’86Gaisser, Steigman & Tilav, ’86

Silk, Olive and Srednicki, ’85Gaisser, Steigman & Tilav, ’86

velocitydistribution

scatt

capture

annihilation

interactions

int. int.

qq

ll W, Z,H

interactions hadronization

cc ,bb ,tt , ,W, Z 0, HH 0

Indirect detection for cyclistsIndirect detection for cyclists

e.g. e.g. 101044 m m22 -telescope searches for 500 GeV WIMP-telescope searches for 500 GeV WIMP

> LHC limit> LHC limit1. 1. - flux - flux

300 km/s

== v v == 2.4 x 104 [ ]cm-2s-1

2. Solar cross section2. Solar cross section

== nn = = ( (N)N) = [1.2x10]57 10-41cm2MM____mmNN

(GF mN2)2 ~

GF2

___mZ

2

MZ2

___mH

4

500 GeV________ mz

500 GeV________ mz

0.4 GeV cm-3 = 8 x 10-4 [ ] cm-3

NN = capture rate = annihilation rate = capture rate = annihilation rate _ WW

250 GeV250 GeV

500 GeV500 GeV

4. Number of muon-neutrinos4. Number of muon-neutrinos

NN = 2 x 0.1 N = 2 x 0.1 N

Leptonic BR~0.1

N = = 3 x 1020 s-1

3. Capture rate by the sun3. Capture rate by the sun

5. 5. = = = = 2 x 10 2 x 10-8 -8 cmcm-2-2 s s-1-1

1 A.U.1 A.U.

5.5 x 105.5 x 102323 cm cm-3-3

6. # events = area x 6. # events = area x x x iceice x x x R x R

10104 4 mm22

• = 10= 10-38-38 cm cm22 = 2.5 x 10 = 2.5 x 10-36-36 cm cm22EE______GeVGeV

• RR = 5m = 625m (E = 5m = 625m (E 0.5 E 0.5 E))EE______GeVGeV

~~__

NN________44dd22

# events = 10 per year# events = 10 per year

AMANDA limitAMANDA limit– – 10 strings only10 strings only

Baikal

Limits: Limits: flux from the Earth/Sun flux from the Earth/SunEarthEarth SunSun

Flux from Earth/Sun and future Flux from Earth/Sun and future GENIUS/CRESST limitsGENIUS/CRESST limits

EarthEarth SunSun

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