Download - Charged Cosmic Rays And Particle Dark Matter
Charged Cosmic Rays And Particle Dark Matter
Dan HooperFermilab
Theoretical Astrophysics Group
Fermilab ColloquiumApril 22, 2009
Dan Hooper - Charged CosmicRays And Particle Dark Matter
Current Status
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Evidence For Dark Matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Evidence For Dark Matter
Galactic rotation curves
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Evidence For Dark Matter
Galactic rotation curves
Gravitational lensing
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Hubble Deep Field
Evidence For Dark Matter
Galactic rotation curves
Gravitational lensing
Light element abundances
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
-Big Bang Nucleosynthesis yields Bh2 ~ 0.01-0.02
-Total matter density is much larger, Mh2 ~ 0.13
Evidence For Dark Matter
Galactic rotation curves
Gravitational lensing
Light element abundances
Cosmic microwave background anisotropies
Large scale structure
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Evidence For Dark Matter
There exists a wide variety of independent indications that
dark matter exists
Each of these observations infer dark matter’s presence through
its gravitational influence
Still no observations of dark matter’s electroweak
interactions (or other non-gravitational interactions)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Evidence For Dark Matter
There exists a wide variety of independent indications that
dark matter exists
Each of these observations infer dark matter’s presence through
its gravitational influence
Still no observations of dark matter’s electroweak
interactions (or other non-gravitational interactions)
Instead of dark matter, might we not understand gravity?
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
NASA/Chandra Press Release, August 21, 2006
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
NASA/Chandra Press Release, August 21, 2006
Baryonic matter (hot gas)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
NASA/Chandra Press Release, August 21, 2006
Baryonic matter (hot gas)
Total Mass
But What Is The Dark Matter?
But What Is The Dark Matter?
Why WIMPs?The thermal abundance of a WIMPT >> M, WIMPs in thermal equilibrium
T < M, number density becomes Boltzmann suppressed
T ~ M/20, Hubble expansion dominates over annihilations;
freeze-out occurs
Precise temperature at which freeze-out occurs, and the density
which results, depends on the WIMP’s annihilation cross section
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Why WIMPs?The thermal abundance of a WIMPAs a result of the thermal freeze-out process, a relic density of WIMPs is left behind:
h2 ~ xF / <v>
For a GeV-TeV mass particle, to obtain a thermal abundance equal to the observed dark
matter density, we need an annihilation cross section of:
<v> ~ pb
Generic weak interaction yields:
<v> ~ 2 (100 GeV)-2 ~ pbDan Hooper - Charged Cosmic Rays And Particle Dark Matter
Why WIMPs?The thermal abundance of a WIMPAs a result of the thermal freeze-out process, a relic density of WIMPs is left behind:
h2 ~ xF / <v>
For a GeV-TeV mass particle, to obtain a thermal abundance equal to the observed dark
matter density, we need an annihilation cross section of:
<v> ~ pb
Generic weak interaction yields:
<v> ~ 2 (100 GeV)-2 ~ pbDan Hooper - Charged Cosmic Rays And Particle Dark Matter
Numerical coincidence? Or an indication that dark matter originates from electroweak-scale physics?
WIMP Hunting
Direct Detection
Indirect Detection
Collider Searches
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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The Indirect Detection of Dark Matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
1. WIMP Annihilation Typical final states include heavy fermions, gauge or Higgs bosons
W+
W-
The Indirect Detection of Dark Matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
1. WIMP Annihilation Typical final states include heavy fermions, gauge or Higgs bosons
2.Fragmentation/Decay Annihilation products decay and/or fragment into combinations of electrons, protons, deuterium, neutrinos and gamma-rays
W+
W-
e+ q
q
p
0
The Indirect Detection of Dark Matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
1. WIMP Annihilation Typical final states include heavy fermions, gauge or Higgs bosons
2.Fragmentation/Decay Annihilation products decay and/or fragment into combinations of electrons, protons, deuterium, neutrinos and gamma-rays
3.Synchrotron and Inverse Compton Relativistic electrons up-scatter starlight/CMB to MeV-GeV energies, and emit synchrotron photons via interactions with magnetic fields
W+
W-
e+ q
q
p
0
e+
The Indirect Detection of Dark Matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Neutrinos from annihilations in the core of the Sun
Gamma Rays from annihilations in the galactic halo, near the
galactic center, in dwarf galaxies, etc.
Positrons/Antiprotons from annihilations throughout the
galactic halo
Synchrotron Radiation from electron/positron interactions
with the magnetic fields of the inner galaxy
Dark Matter With Charged Cosmic Rays
WIMP annihilation products fragment and decay, generating equal numbers of electrons and positrons, and of protons and antiprotons
Charged particles move under the influence of the Galactic Magnetic Field; Electrons/positrons lose energy via synchrotron and inverse Compton scattering
Astrophysical sources are generally expected to produce
far more matter than antimatter; large positron/antiproton
content in the cosmic ray spectrum could
provide evidence for dark matterDan Hooper - Charged Cosmic Rays And Particle Dark Matter
Charged Particle Astrophysics With
Pamela
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Major step forward in sensitivity to GeV-TeV
cosmic ray electrons, positrons, protons, antiprotons, and light nuclei
Among other science goals, PAMELA hopes to identify
or constrain dark matter annihilations in the Milky Way halo by measuring the cosmic positron and antiproton spectra
Charged Particle Astrophysics With
Pamela
Combination of tracker and calorimeter enable charge, mass, and energy determinations
Very accurate particle IDTracker
Calorimetere- e+
p+
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela’s New Antiproton Measurement
Pamela Collaboration, arXiv:0810.4994
Best measurement to dateDramatically smaller error bars above ~1-10 GeV
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela’s New Antiproton Measurement
Best measurement to dateDramatically smaller error bars above ~1-10 GeV
The antiprotons detected by Pamela are consistent with being entirely from secondary production (byproduct of cosmic ray propagation)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela Collaboration, arXiv:0810.4994
Pamela’s New Positron Measurement
Pamela Collaboration, arXiv:0810.4995Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela’s New Positron Measurement
Pamela Collaboration, arXiv:0810.4995
First glance: -Is this all screwed up?
Charge-dependent solar modulation important below 5-10 GeV!
(Pamela’s sub-10 GeV positrons appear as they should!)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela’s New Positron Measurement
Pamela Collaboration, arXiv:0810.4995
First glance: -Is this all screwed up?
Charge-dependent solar modulation important below 5-10 GeV!
(Pamela’s sub-10 GeV positrons appear as they should!)
Astrophysical expectation (secondary production)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Pamela’s New Positron Measurement
Pamela Collaboration, arXiv:0810.4995
First glance: -Is this all screwed up?
Charge-dependent solar modulation important below 5-10 GeV!
(Pamela’s sub-10 GeV positrons appear as they should!)
Astrophysical expectation (secondary production)
Rapid climb above 10 GeV indicates the presence of a primary source of cosmic ray positrons!
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
And if you think the Pamela result is surprising…
The New Cosmic Ray Electron Spectrum From
ATIC
In a series of balloon flights, ATIC has measured a 4-5 excess of cosmic ray electrons between 300 and 800 GeV (Nature, Nov. 21, 2008) This requires a local source of cosmic ray electrons/positrons (within ~1 kpc)
If we extrapolate the Pamela positron fraction up to higher energies, the ATIC result approximately matchesDan Hooper - Charged Cosmic Rays And Particle Dark Matter
WMAP and Energetic Electrons/Positrons
WMAP does not only detect CMB photons, but also a number of galactic foregrounds
GeV-TeV electrons emit hard synchrotron in the
frequency range of WMAP
Thermal Dust
Soft Synchrotron (SNe)
Free-Free
WMAP
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
=
+
+
+
Free-
free
T & S
Dust
CMB
WMAP
Synchrotr
on
=
+
+
+
Free-
free
T & S
Dust
CMB
WMAP
Synchrotr
on
Well, actually… No
-
+
+
+
Free-
free
T & S
Dust
CMB
WMAP
Synchrotr
on
= …
22 GHz
“The WMAP Haze”
22 GHz
After known foregrounds are subtracted, an excess appears in the residual maps within the inner ~20 around the Galactic Center
“The WMAP Haze”
Pamela, ATIC, and WMAPHighly energetic electrons and positrons are surprisingly common both locally, and in the central kiloparsecs of the Milky Way
Not the product of any plausible propagation mechanism or other such effect (see P. Serpico,
arXiv:0810.4846)
Constitutes the discovery of bright sources of e+e- pairs with a very hard spectral index
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela, ATIC, and WMAP
Signals
The distribution and spectrum of the WMAP haze are consistent with being of dark matter origin
The spectral features observed by Pamela and ATIC could also
be generated by dark matter annihilations
Hall and Hooper, arXiv:0811.3362
Cholis, Goodenough, Hooper, Simet, Weiner arXiv:0809.1683
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
… but not necessarily easily.
Dark Matter as the Source of the Pamela and ATIC
Signals
… but not necessarily easily.
Challenges Faced Include:1)Very hard spectrum
Pamela
Hooper and J. Silk, PRD, hep-ph/04091040Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Challenges Faced Include:1)Very hard spectrum
2)Too many antiprotons, gamma rays, synchrotron
Pamela
Hooper and J. Silk, PRD, hep-ph/04091040
… but not necessarily easily.
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Challenges Faced Include:1)Very hard spectrum
2)Too many antiprotons, gamma rays, synchrotron
3)Requires a very high annihilation rate
Pamela
Hooper and J. Silk, PRD, hep-ph/04091040
… but not necessarily easily.
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Particle Physics Solutions:
Dark Matter as the Source of the Pamela and ATIC
Signals
Particle Physics Solutions:1) Very hard injection spectrum (a large fraction of annihilations to e+e-, +- or +-)
Cholis, Goodenough, Hooper, Simet, Weiner arXiv:0809.1683
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Particle Physics Solutions:1)Very hard injection spectrum (a large fraction of annihilations to e+e-, +- or +-)
1)For example, the lightest Kaluza-Klein state in a model with a universal extra dimenison
(UED) fits remarkably well (or a KK- or other particle
which annihilates to light fermions through a Z)
Hooper, K. Zurek, arXiv:0902.0593;Hooper, G. Kribs, PRD, hep-ph/0406026;
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Dark Matter as the Source of the Pamela and ATIC
Signals
Particle Physics Solutions:1)Very hard injection spectrum (a large fraction of annihilations
to e+e-, +- or +-)
2)Annihilation rate dramatically increased by non-perturbative effects known as the “Sommerfeld Enhancement” -Very important for m<<mX
and vX<<c (such as in the halo, where vx/c~10-3)
X
X
SM
SM
X
X
SM
SM
Arkani-Hamed, Finkbeiner, Slatyer, Weiner, arXiv:0810.0713; Cirelli and Strumia, arXiv:0808.3867; Fox and Poppitz, arXiv:0811.0399
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Astrophysical Solutions:
Dark Matter as the Source of the Pamela and ATIC
Signals
Astrophysical Solutions:1)More small-scale structure than expected (a “boost factor” of ~103)
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Astrophysical Solutions:1)More small-scale structure than expected (a “boost factor” of ~103)
2)A narrow diffusion region
D. Hooper and J. Silk, PRD, hep-ph/04091040Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Dark Matter as the Source of the Pamela and ATIC
Signals
Astrophysical Solutions:1)More small-scale structure than expected (a “boost factor” of ~103)
2)A narrow diffusion region
3)A large nearby clump of dark matter
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
A Nearby Clump of Dark Matter?
In the standard picture, WIMPs distributed throughout the halo contribute to the spectrum of cosmic ray electrons and positrons
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
A Nearby Clump of Dark Matter?
In the standard picture, WIMPs distributed throughout the halo contribute to the spectrum of cosmic ray electrons and positrons
Nearby sources produce a harder spectrum (less propagation)
Motion of clump hardens the spectrum further
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Hooper, A. Stebbins and K. Zurek, arXiv:0812.3202
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
A Nearby Clump of Dark Matter?
A clump of neutralino dark matter ~1 kpc from the Solar System provides an excellent fit to Pamela and ATIC while also:
Evading constraints from antiproton, gamma ray, and synchrotron measurements
Providing a plausible scenario for generating the required very high annihilation rate
Hooper, A. Stebbins and K. Zurek, arXiv:0812.3202
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Did Dark Matter Have Anything To Do With The Reionization Of
Our Universe?
The atoms in our universe have undergone two major phase transitions:
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Did Dark Matter Have Anything To Do With The Reionization Of
Our Universe?
The atoms in our universe have undergone two major phase transitions:
1)370,000 years after the big bang, electrons and protons combine to form neutral atoms, and release the cosmic microwave background
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Did Dark Matter Have Anything To Do With The Reionization Of
Our Universe?
The atoms in our universe have undergone two major phase transitions:
1)370,000 years after the big bang, electrons and protons combine to form neutral atoms, and release the cosmic microwave background
2)Between z~6-20, our universe’s gas once again became ionized
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Over the first billion years, dark matter had begun to form clumps and annihilate efficiently
Dark matter annihilation products include gamma rays, which can scatter with electrons, causing gas to become reionized
If one in ~109 dark matter particles annihilate during this era, the energy released would be sufficient to completely reionize the universe
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
W+
W-
e+
q
q0
e+
Did Dark Matter Have Anything To Do With The
Reionization Of Our Universe?
Did Dark Matter Reionize Our Universe?
For a typical WIMP, however, annihilations in the first billion years of our universe’s history only lead to ~1% of the atoms being reionized
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Belikov and Hooper, arXiv:0904.1210
Did Dark Matter Reionize Our Universe?
For a typical WIMP, however, annihilations in the first billion years of our universe’s history only lead to ~1% of the atoms being reionized
If the WIMP has a larger cross section, as required by PAMELA and/or ATIC, however, their annihilations would be predicted to fully reionize the universe! Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Belikov and Hooper, arXiv:0904.1210
Did Dark Matter Reionize Our Universe?
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Cross section range required for PAMELA
Observed degree of reionization
Belikov and Hooper, arXiv:0904.1210
Did Dark Matter Reionize Our Universe?
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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PAMELA Only
If annihilating dark matter is responsible for the PAMELA or ATIC signals, then dark matter is also predicted to have played a dominant role in reionizing the universe!
PAMELA+ATIC
Belikov and Hooper, arXiv:0904.1210
High-Energy Positrons From
Nearby Pulsars
Rapidly spinning (~msec period) neutron stars, accelerate electrons to very high energies (power from slowing rotation - spindown)
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Blasi and Serpico, arXiv:0810.1527 Yuksel, Kistler, Stanev, arXiv:0810.2784 Profumo, arXiv:0812.4457
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby Pulsars
Rapidly spinning (~msec period) neutron stars, accelerate electrons to very high energies (power from slowing rotation - spindown)
Energies can exceed the pair production threshold
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby Pulsars
Rapidly spinning (~msec period) neutron stars, accelerate electrons to very high energies (power from slowing rotation - spindown)
Energies can exceed the pair production threshold
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e+
Fermi/Glast Sky MapDan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby Pulsars
Rapidly spinning (~msec period) neutron stars, accelerate electrons to very high energies (power from slowing rotation - spindown)
Energies can exceed the pair production threshold
Very young pulsars (<10,000 years) are typically surrounded by a pulsar wind nebula, which can absorb energetic pairs
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~
Vela Pulsar (12,000 years old)Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby Pulsars
Rapidly spinning (~msec period) neutron stars, accelerate electrons to very high energies (power from slowing rotation - spindown)
Energies can exceed the pair production threshold
Very young pulsars (<10,000 years) are typically surrounded by a pulsar wind nebula, which can absorb energetic pairs
Most of the spindown power is expended in first ~105 years
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Vela Pulsar (12,000 years old)Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby PulsarsTwo promising candidates:Geminga (157 pc away, 370,000 years old)B0656+14 (290 pc, 110,000 years)
Geminga B0656+14
Hooper, P. Blasi, P. Serpico, JCAP, arXiv:0810.1527
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
High-Energy Positrons From
Nearby PulsarsTwo promising candidates:Geminga (157 pc away, 370,000 years old)B0656+14 (290 pc, 110,000 years)
Geminga B0656+14
Hooper, P. Blasi, P. Serpico, JCAP, arXiv:0810.1527
A few percent of the total spindown energy is needed in high energy e+e- pairs
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Secondary Positrons From The Acceleration
Region?
The standard prediction for secondary positron production is calculated by combining the spectrum of cosmic ray protons, the density of targets, and the spectrum of cosmic ray electrons; Leads to a steadily falling positron fraction
It has recently been suggested that if secondary positrons are produced inside of cosmic ray acceleration
regions, their spectrum may be hardened, potentially causing the positron fraction to rise
P. Blasi, arXiv:0903.2794Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Many Questions, Few Answers
The current set of data does not allow us to identify the origin of the Pamela, ATIC, and WMAP signals
Further complementary measurements are going to be required to answer the question of these particles’ origin
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Test #1:Search For An
Electron/Positron Dipole Anisotropy With Fermi
Hooper, P. Blasi, P. Serpico, JCAP, arXiv:0810.1527
Diffusion of electrons/positrons remove almost all directional information
If the Pamela/ATIC signal arises from a single nearby source (pulsar, dark matter clump), a 0.1% dipole anisotropy can remain
Too small to be seen by Pamela, but may be within the reach of Fermi
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Test #2:Measure The ATIC Feature With Gamma Ray Telescopes
The spectral feature observed by ATIC could be the product of:
A nearby pulsar
Dark matter annihilating to e+e- or other charged leptons
Nearby dark matter annihilating to W+W-
J. Hall and D. Hooper, arXiv:0811.3362
Cannot be distinguished with current precision (exposure limited)Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Ground-based telescopes use the entire atmosphere as a target, and thus have much larger collecting areas (~105 m2) than balloon experiments such as ATIC (~1 m2)
Ground-based telescopes, however, have a more difficult
time identifying/separating showers produced by electrons,
protons, and gamma-rays
The biggest challenge in measuring the cosmic ray
electron spectrum lies in efficiently rejecting hadrons (~99% currently,
moving toward 99.9% in the future)
J. Hall and D. Hooper, arXiv:0811.3362
Test #2:Measure The ATIC Feature With Gamma Ray Telescopes
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Even with conservative assumptions regarding performance, existing data from HESS or VERITAS should be sufficient to distinguish between these possibilities with very high significance
Once this analysis is performed, we should know one way or the other whether dark matter annihilating directly to e+e- is responsible for the excess observed by ATIC
J. Hall and D. Hooper, arXiv:0811.3362
Test #2:Measure The ATIC Feature With Gamma Ray Telescopes
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Very recently, the HESS collaboration published its electron spectrum between ~700 GeV and several TeV (ie. just above the energy range of interest!)
Considering how small the (statistical) error bars at ~700 GeV, there is every reason to believe that HESS (or VERITAS) will be capable of measuring the shape of the electron spectrum over the ATIC feature
Test #2:Measure The ATIC Feature With Gamma Ray Telescopes
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HESS Collaboration, arXiv:0811.3894Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
On monday, May 4th, 11:09-11:21 AM, the Fermi Collaboration is scheduled to announce the “First results on the high energy cosmic ray electron spectrum from Fermi-LAT” at APS Meeting in Denver
This will likely resolve/clarify the nature of the ATIC feature considerably
Test #2:Measure The ATIC Feature With Gamma Ray Telescopes
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
The Planck satellite is scheduled for launch within the next month or so
With far superior angular resolution and frequency coverage than WMAP, Planck will measuring in much greater detail the properties of the synchrotron haze from the Galactic Center
Test #3:Study the Synchrotron Haze With
Planck
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
As the Pamela collaboration accumulates and analyzes more data, they project that they will measure the positron fraction up to approximately 270 GeV
Such information can be used to further constrain the properties of a WIMP or other source
Test #4:More Data From Pamela
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
In august, the FERMI collaboration announced their first results!
The sky map collected by FERMI in its first four
days was already more detailed than that obtained by EGRET over its entire mission
Test #5:Search For Gamma Ray Dark
Matter Annihilation Products With Fermi
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Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
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Where To Look For Dark Matter With
Fermi?
Diemand, Kuhlen, Madau, APJ, astro-ph/0611370
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Where To Look For Dark Matter With
Fermi?The Galactic Center-Brightest spot in the sky-Considerable astrophysical backgrounds
Diemand, Kuhlen, Madau, APJ, astro-ph/0611370
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Where To Look For Dark Matter With
Fermi?The Galactic Center-Brightest spot in the sky-Considerable astrophysical backgrounds
The Galactic Halo-High statistics-Requires detailed model of galactic backgrounds
Diemand, Kuhlen, Madau, APJ, astro-ph/0611370
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Where To Look For Dark Matter With
Fermi?The Galactic Center-Brightest spot in the sky-Considerable astrophysical backgrounds
The Galactic Halo-High statistics-Requires detailed model of galactic backgrounds
Individual Subhalos-Unlikely detectable-Low backgrounds
Diemand, Kuhlen, Madau, APJ, astro-ph/0611370
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
Where To Look For Dark Matter With
Fermi?The Galactic Center-Brightest spot in the sky-Considerable astrophysical backgrounds
The Galactic Halo-High statistics-Requires detailed model of galactic backgrounds
Extragalactic Background-High statistics -potentially difficult to identify
Individual Subhalos-Unlikely detectable-Low backgrounds
Diemand, Kuhlen, Madau, APJ, astro-ph/0611370
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
SummaryThe sensitivity of direct and indirect searches for dark matter and each rapidly advancing
Pamela, ATIC, and WMAP have intriguing detections of 10 -1000 GeV electrons/positrons in the Milky Way - consistent with being the first detections of particle dark matter!
FERMI/GLAST will almost certainly shed a great deal of light on these observations - more results expected soon!
If dark matter is responsible for the Pamela or ATIC signals, then it is also likely to have played a major role in the reionization of our universe
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Summary
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
One Year From NowNew limits from CDMS, XENON-100, at or below the ~10-8 pb level, ruling out essentially the entire focus point SUSY region (or the first observation of WIMP-nuclei scattering)
First full year of FERMI/GLAST data PAMELA positron spectrum up to 200-270 GeV?
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Summary
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
One Year From NowNew limits from CDMS, XENON-100, at or below the ~10-8 pb level, ruling out essentially the entire focus point SUSY region (or the first observation of WIMP-nuclei scattering)
First full year of FERMI/GLAST data PAMELA positron spectrum up to 200-270 GeV?
Three Years From NowTon-scale direct detection experiments Results from Planck, IceCube, Glast, PamelaDiscovery of SUSY or other new physics at the LHC
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Summary
Dan Hooper - Charged Cosmic Rays And Particle Dark Matter
One Year From NowNew limits from CDMS, XENON-100, at or below the ~10-8 pb level, ruling out essentially the entire focus point SUSY region (or the first observation of WIMP-nuclei scattering)
First full year of FERMI/GLAST data PAMELA positron spectrum up to 200-270 GeV?
Three Years From NowTon-scale direct detection experiments Results from Planck, IceCube, Glast, PamelaDiscovery of SUSY or other new physics at the LHC
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Welcome to the Discovery Era!