Up-to-date Cosmic p-ISM Interaction Modeling and
“Anomalies” in g-Rays, Positrons, and Anti-Protons
13 January, 2005
Tune Kamae (SLAC)
(in collaboration with colleagues at SLAC)
Plan of this Talk
Galactic diffuse g-ray emission
“GeV Excess” in the EGRET spectrum
Recent work on p-ISM interaction
What are new in this work
Model A with diff. process and scaling violation
GeV Excess explained?
Anomalies in e+ and p-bar explained?
Conclusion and future Prospects
13 January, 2005
Seminar at UCSC
1
Galactic Diffuse g-ray Emission: COS-B Observation
- First glimpse into cosmic ray interaction with ISM Galactic diffuse emission by pp->pi0, bremsstrahlung, and inverse-Compton scattering
predicted by Ginzburg, Hayakawa and others in 1960’s.
Local structure
(Ophiuchus)
Cygnus
region
13 January, 2005
Galactic
Center
Seminar at UCSC
Geminga
pulsar
Vela
pulsar
Crab
pulsar
2
Gal. Diffuse Emission, Accel. Sites, and CR Propagation
- Interplay of CR, ISM and B-field Star light
(rad. field)
Accel. sites
(SNR, pulsar)
p0 production
(direct + decay)
in GMC
Escaping
proton
Escaping electron
Trapped proton
Galactic Ridge
Trapped electron
IC by
elect
(diff)
Synch.
IC at
rad. at
(diff)
accel site (conf) accel site
(conf)
(confined)
p0(g)
p0(g)
Brems.
(diffuse)
Galactic Halo
Earth
13 January, 2005
Seminar at UCSC
3
Galactic Diffuse g-ray: Modeling of pp Interaction
- Early models for pp -> p0 inclusive production Galactic diffuse emission by pp->pi0: Predicted by S. Hayakawa, Ginzburg, et al.
Early models of PP->pi0 for astrophysical applications: Stecker, Stephens & Badwar, and Dermer
Data from Fermi Lab
Earlier models need to be re-examined with
data from ISR, CERN-SPS, and Fermi Lab
and measurements.
13 January, 2005
Seminar at UCSC
4
Galactic Diffuse g-ray: EGRET Observation
- Intensity Map -
Galactic Ridge
13 January, 2005
Seminar at UCSC
5
Galactic Diffuse g-ray: Diffuse Emission
- 271 point-sources subtracted -
Eg=70-100MeV
Av. Intensity
of this region
Eg=100-150MeV
Eg=150-300MeV
13 January, 2005
Seminar at UCSC
6
Galactic Diffuse g-Ray: EGRET GeV Excess
Hunter et al. 1997
E2dN/dE
Data
6<b<10
Scaling model
prediction
dN/dE
Excess
2<b<6
-2<b<2
Data
-6<b<-2
Eg [MeV]
Eg [MeV]
13 January, 2005
Seminar at UCSC
Scaling model
prediction
7
ISM-Bound Emission: No.1/2
- Longitudinal distribution predicted by Strong, Moskalenko, & Reimer Eg=100-150MeV
GC
Eg=500-1000MeV
GC
Eg=150-300MeV
GC
Eg=1-2GeV
Eg=300-500MeV
GC
Eg=2-4GeV
GC
GC
13 January, 2005
Seminar at UCSC
8
ISM-Bound Emission: No.2/2
- Glat Distr for 3 Glon Regions (-74~-34,-30~30,34~74) Thickness of the measured Galactic disk: independent of Eg and Glon
Galactic
Plane
Galactic
Plane
Galactic
Plane
Intensity map from the EGRET archive
l=-74~-34
Deconvoled
l=-30~-30
Deconvoled
l=34~-74
Deconvoled
New intensity map by T.K. et al to be published
13 January, 2005
Seminar at UCSC
9
Galactic Diffuse g-ray: Modern Simulation Studies No.1/2
- PP p0 g-ray in SNR and Galactic Ridge -
Proton’s
power-law
index = 2.0
Scaling
law
Isobar
Model
(Dermer)
Isobar
Model
(Dermer)
13 January, 2005
Scaling
law
Seminar at UCSC
Proton’s
power-law
index =
2.0,2.25,2.5
10
Galactic Diffuse g-ray: Modern Simulation Studies No.2/2
- Run with Early Version of Pythia M. Mori simulated pp > p0 > g-ray using HADRIN and PYTHIA in 1997 and
concluded that their prediction is similar to the scaling model predictions.
Index of protons
~2.73
13 January, 2005
Seminar at UCSC
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What Are New in The Present Work?
1.
2.
Diffractive process (“Renormalized”) in the cosmic PP interactions.
Scaling Violation (Pythia with CDF Tune A) in the cosmic PP interactions.
A.
B.
All secondary particle fluxes will increase in the GeV-TeV range.
Diffraction dissociation favors positively charged secondary particles.

Three “anomalies” may be explained by diffractive process and scaling violation:
•
GeV Excess in Galactic g-ray spectrum
•
p-bar flux at Earth
•
e+ spectrum at Earth
Parameterized g, e-, e+, n, n-bar, p-bar inclusive spectra for 0.5 GeV<Tp<512 TeV

Programs used:
• Pythia 6.2 (with CDF Tune A),
• U. W.-Milwaukee parameterization of the Stephens-Badhwar model [coded by TK]
• Diffraction Dissociation model (DiffDissocSimNew.py) [coded by TK]
13 January, 2005
Seminar at UCSC
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Our Model A and Model B
 Model A (the most-updated and our preferred model):
stot(pp)=sel+sinel(non-diff)+sinel(diffractive)
Non-diffractive inelastic interaction:
• Tp>=62.5GeV: Pythia 6.2 with “Scaling violation” through “multiple
interaction” (CDF TuneA included in Pythia 6.2)
• Tp<62.5GeV: Parameterized version of the Stephens-Badhwar Model
(by a group at U. of Wisconsin at Milwaukee) (same for Model B)
Diffraction process: (DiffDissocSimNew.py)
• “Renormalized” diffraction model by K. Goulianos 1995
 Model B (used for confirmation: no scaling violation in the non-diff part nor
no “renormalization” in diff part)
Non-diffractive inelastic interaction:
• Tp>=62.5GeV: Pythia 6.1 without “Scaling violation”
13 January, 2005
Seminar at UCSC
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PP Cross Sections: Scaling Model (Model B)
- Particle Physics in 1960-1970 -
13 January, 2005
Seminar at UCSC
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PP Cross Sections: Our Model A
- Scaling Violation & Renormalized Model of Diffraction -
Our Model A
13 January, 2005
Scaling Model
Seminar at UCSC
15
Pythia with Scaling Choice with Model B Cross-Section
- Inclusive gamma-ray cross-section -
Model B
Tp=256TeV
Tp=512TeV
Tp=62.5GeV
13 January, 2005
Seminar at UCSC
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Pythia with Scaling Violation and Model A Cross-Section
- Inclusive gamma-ray cross-section -
Tp=256TeV
Tp=512TeV
Tp=62.5GeV
13 January, 2005
Seminar at UCSC
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Low Energy PP Interaction: Stephen & Badhwar Model No.1/2
S. R. Blattnig et al., “Parametrizations of Inclusive Cross-Sections for Pion
Production in Proton Proton Collisions“, Phys. Rev. D62, 094030 (2000)
Common to Model A and Model B except for cross-section
13 January, 2005
Seminar at UCSC
18
Low Energy PP Interaction: Stephen & Badhwar Model No.2/2
- Gamma-Ray Spectrum Common to Model A and Model B except for cross-section
S. R. Blattnig et al., “Parametrizations of Inclusive Cross-Sections for Pion
Production in Proton Proton Collisions“, Phys. Rev. D62, 094030 (2000)
13 January, 2005
Seminar at UCSC
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Diffractive Process: No.1/3
- Monte Calro Simulator “DiffDissocSimNew.py”Diffractive Processes
Projectile region
Target
region
Projectile-Diff. Proc.
Single-Diff. Proc.
Target-Diff. Proc.
Double-Diff. Proc.
Mass2 of “excited fireball”
Projectile
region
Target region
Projectile region
Mass2 of “excited fireball”
13 January, 2005
Target region
Mass2 of “excited fireball”
Seminar at UCSC
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Diffractive Process: No.2/3
- Monte Calro Simulator “DiffDissocSimNew.py”Double-Diff. Proc.
pLab of the
projectile fireball
Nch of the
projectile
fireball
13 January, 2005
Seminar at UCSC
pLab of the target
fireball
Nch of the
target
fireball
21
Diffractive Process No.3/3
- Double peaked spectra with low multiplicity -
13 January, 2005
Seminar at UCSC
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Relative g-Ray Yields: Model A and Model B
- Non-Diffractive Process -
Model A = 1.65 x Model B
13 January, 2005
Seminar at UCSC
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Relative g-Ray Yields: Model A Diff and Non-Diff
- Importance of Diffractive Process -
Diff. contributes
significantly here.
13 January, 2005
Seminar at UCSC
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Verification of Model A: No.1/2
- Charged Multiplicity Distribution UA5 Data
Model A
Scaling Model
13 January, 2005
Seminar at UCSC
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Verification of Model A: No.2/2
- Pi-zero Multiplicity -
Model A
Scaling
Model
13 January, 2005
Seminar at UCSC
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Cosmic Proton Spectrum in Galactic Ridge: Galprop No.1/2
- Galaxy simulator by Strong and Moskalenko LIS
Moskalenko, Strong, Ormes & Potgieter
ApJ, 565, 280 (2002)
Local Intersteller Spectrum (LIS)
Modulation by Solar B-field
and Solar Wind
Near Earth
Spectrum near Earth (Near Earth)
LIS
Particle
interaction
modeling
Near Earth
13 January, 2005
Seminar at UCSC
27
Cosmic Proton Spectrum in Galactic Ridge: Galprop No.2/2
- Galaxy simulator by Strong and Moskalenko Slightly harder “injection spectrum” at cosmic-ray sources: our Trial4GR spectrum
Boron/Carbon
ratio
Positron spectrum
p-bar spectrum
LIS under-predict
13 January, 2005
Seminar at UCSC
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Galactic Diffuse g-ray Spectrum for Ind=2, LIS and Trial4GR
Prediction of Model A
Prediction of Scaling Models
Scaling Models
Model A
Model A predicts:
1) a harder g-ray spectrum
(diffractive process)
2) a higher flux
(rising non-diff. cross-sec.
and scaling violation)
than scaling models
13 January, 2005
Seminar at UCSC
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GeV Excess Explained ? No.1/2
Gamma-rays from pp  p0
EGRET Intensity in
L=(-30,30) B=(-5,5)
Model A
(LIS)
Model B
(LIS)
SMR04 (LIS)
13 January, 2005
Seminar at UCSC
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GeV Excess Explained? No.2/2
Our p0 g + Brems + IC (Galprop, LIS)
Explains about 50%
of the Excess with LIS.
Explains the Excess
fully with Trial4GR.
EGRET
Model A
(Trial4GR)
Model A (LIS)
Scaling Models
13 January, 2005
Seminar at UCSC
31
Anomalies in e+ and p-bar ? No.1/2
de Boer et al. 2003
Neutralino decay to g-ray?
13 January, 2005
Neutralino decay to p-bar?
Seminar at UCSC
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Anomalies in e+ and p-bar ? No.2/2
de Boer et al. 2003
Measurement by HEAT collaboration
(e+ spectrum by a series of balloon exp.)
13 January, 2005
Seminar at UCSC
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Model A Prediction on p-bar Spectrum
Exp. data
Model A vs. Model B
Scaling model
with LIS
13 January, 2005
Seminar at UCSC
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Model A Prediction on Positrons Spectrum
Diffractive process favors
e+ over e-
Non-Diffractive process
dominates overall spectrum
e+
e-
13 January, 2005
Seminar at UCSC
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Parameterization of pp > g Inclusive Cross-Sections
Non-diffractive
red: fit to simulated data
blue: parameterization
Diffractive dissoc.
red: fit to simulated data
blue: parameterization
Definition of P0-P8: x = log10(Tp) 0.000488<Tp< 512.0TeV
[0]*exp(-[1]*( x-[3] + [2]*(x-[3])**2)**2) +
[4]*exp(-[5]*( x-[8] + [6]*(x-[8])**2 + [7]*(x-[8])**3)**2)
13 January, 2005
ds(g incl)/dlogE = Sum of the following two “skewed” Gaussians
[0]*exp(-[1]*((x-[2])/(1.0+[3]*(x-[2])))**2)
[4]*exp(-[5]*((x-[6])/(1.0+[7]*(x-[6])))**2)
Seminar at UCSC
36
Parameterization of pp > e+/- Inclusive Cross-Sections
Non-diffractive
Diffractive dissoc.
red: parameterization for e+
blue: parameterization for e-
red: parameterization for e+
blue: parameterization for e-
Definition of P0-P8: x = log10(Tp) 0.000488<Tp< 512.0TeV
[0]*exp(-[1]*( x-[3] + [2]*(x-[3])**2)**2) +
[4]*exp(-[5]*( x-[8] + [6]*(x-[8])**2 + [7]*(x-[8])**3)**2)
13 January, 2005
ds(g incl)/dlogE = Sum of the following two “skewed” Gaussians
[0]*exp(-[1]*((x-[2])/(1.0+[3]*(x-[2])))**2)
[4]*exp(-[5]*((x-[6])/(1.0+[7]*(x-[6])))**2)
Seminar at UCSC
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Conclusion and Prospects for GLAST
1.
Accurate modeling of p(a)-ISM interaction is likely to explain the GeV Excess
with minor modification in the cosmic proton (a) spectrum.
2.
We expect a higher anti-proton flux for Model A (rising s and scaling violation).
3.
Excess of e+ flux over e- expected for E > 5 GeV by the diffractive process.
4.
With much improved g-ray data from GLAST and e+/p-bar data from PAMELA,
we can map the baryonic matter distribution in the Galaxy accurately.
5.
We will incorporate our Model A to Galprop and make a very reliable model of
Galaxy in near future.
13 January, 2005
Seminar at UCSC
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What can we do beyond GLAST?
1.
Parameterize angular distri. of secondaries >> Simulate AGN jets
>> g-rays from filaments in SNR
2.
Include multiple Pomeron Ex. (in diff. dissoc.), mini-jets (multiple parton int.)
and nuclear effects >> Calibrate AGASA/Hires/Auger and study UHE
3.
New particle physics?
>> Study the first UHE interaction in the upper atmosphere
13 January, 2005
Seminar at UCSC
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