examples of science generic fluxes associated with cosmic rays generic fluxes associated with cosmic...
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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.
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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