Massimo Persic INAF/INFN-Trieste MAGIC Collaboration

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Massimo PersicINAF/INFN-Trieste MAGIC
Collaboration
GeV-TeV prospects results

• Issues
• Origin diffusion properties
• of Galactic CRs
• Main accelerators SNRs?
• Diffusion measure it?
• Galaxies massive SFR
• AGNs variability, SED, EBL
• GRBs SED, emission
• pulsars emission region

Massimo Persic INAF-INFN Trieste MAGIC
Collaboration
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SNR shell ? particle acceleration Resolved shell
in VHE-g-rays g-rays from leptonic or hadronic
channels?
SNR RX J1713.7-3946
H.E.S.S.
Aharonian 2006
leptonic channel favd
3EG J1714-3857
hadronic channel favored
B100mG
Berezhko Völk 2006
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Leptonic Ee 20 (Eg )1/2 TeV 110 TeV
but KN sets on .. ? 100 TeV Hadronic Ep
Eg / 0.15 30 / 0.15 TeV 200 TeV
... but is SN statistics enough to fit CR energy
density?
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HESS J1813-178
Albert 2006
???
ABBA
MAGIC
AGILE Fermi LAT
IACT
Hadronic 2MÄ of target gas, exp-cutoff proton
distrib a2.1, Ec100 TeV,
np6cm-3, L(0.4-6 TeV)2.5E34erg/s Leptonic
B10mG, exp-cutoff electron distrib a2.0,
Ec20TeV
VHE g-rays hadronic or leptonic ?
D 4 kpc
GeV data ? solve TeV spectral degeneracy ?
CRp normalization
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Aharonian 2006
index G2-2.2 (strong shock) little variation
across SNR

• GeVTeV ? spatially resolved spectroscopy
• young SNRs (tlttcool (p,e))
• CRp spectrum g 12a b
• ? measure k(p) as a function of p

• pb b0.6 ?
• from B/CNO ratio

from VHE
from radio
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Galaxies
Integrated view of VHE em. from massive SF
acceleration, diffusion, energy loss
Arp 220
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M82 most promising candidate
MP, Rephaeli Arieli 2008
diffusion-loss eq. solved
F(gt0.1 TeV) 2 x10-12 cm-2s-1
MAGIC or VERITAS hundreds of hours
F(gt100 MeV) 10-8 cm-2s-1
Fermi LAT first-year scan
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Crab pulsar detection
First detection of pulsed emission at gt25
GeV. Searches going on for 35 years!!
EGRET MAGIC pl exp E/16.3 GeV)
pl exp (E/20.7 GeV)2

• at least for Crab pulsar,
• polar cap scenario challenged

More psr obss ms pulsars?
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Active Galactic Nuclei
IACT
Fermi AGILE
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Mrk 421
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Jul/Aug Nov/Dec 2007
(SE)SC model Ghisellini 2007
3C454.3 z0.859
AGILE trigger
MAGIC
MAGIC
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March/April 2008
AGILE
MAGIC
Fermi
First ever simultaneous HEVHE g-ray obs of a
blazar!
p r e l i m i
n a r y
PG 1553113
(?)
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• Target-of-Opportunity (ToO) obss ? high states
• trigger in other l (g AGILE, Fermi x Swift,
  Suzaku optical KVA)
• simultaneous mwl observations
• evolution of emitting particle population
• emergy-dependent evolution in time

• Monitoring obss ? low states
• in several l
• check quiet emission of blazar
• properties of steady-state particle spectrum
• emergy-dependent evolution in time

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• Limitless possibility for
• IACT follow-up?

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Cross section (differ.)
EBL
Hauser Dwek 2001
Stecker 2006
TeV g E soft g e
E 1TeV ? sgg max for e0.5 eV (2mm, K-band)
Heitler 1960
x1cosq

• Optical depth

Slkkkàkàk-lkn
Stecker 1999
IBL absorption
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Franceschini et al. 2008
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Measuring EBL(z). Tools sources with sound
modeling minimum number of parameters ?
BLLacs!? (l.o.s. orientation, jet-only emission,
single-zone SSC). 1) Based on GeV data, set up a
list of BLLacs whose predicted VHE flux is
detectable with IACTs. Populate redshift space
(out to z 1) as closely as possible. 2) For
each BLLac source, obtain simultaneous
well-sampled mwl SEDs (at optical, X-ray, HE, and
VHE frequencies) corresponding to different
source states (low, high). This amounts to
having several SEDs at each given z. Since in
such SEDs the Compton peak typically occurs in
the EBL-unaffected region lt100GeV, using HE data
the SSC model can be closed with substantially no
EBL-induced bias. Hence, the SSC model in the VHE
region (gt100 GeV) is known and can be assumed to
represent the intrinsic VHE source spectrum.
Contrasting it with data (measured between
photon energies E1 and E2), we obtain nEBL(z) at
redshift z and in the energy interval between,
locally at redshift z, 0.5/E2(1z) eV and
0.5/E1(1z) eV. 3) Repeating procedure (2)
with different SEDs (i.e. different sources, or
same source in different emission states) at the
same z, in principle we should obtain consistent
determinations of the EBL. In practice, we will
reduce the statistic error affecting each
determination of nEBL(z). 4) Selecting BLLac
objects progressively farther away, we will
measure EBL at different z. By repeating steps
(2),(3) we will in principle obtain measures of
nEBL(z) -- out to z 1.
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Gamma-Ray Bursts (GRBs)

• Most energetic explosions since Big Bang (1054
  erg if isotropic)
• Astrophysical setting unknown (hypernova?)
• Emission mechanism unknown (hadronic vs
  leptonic, beaming,
• size of emitting region, role of environment,
  )
• Cosmological distances (z gtgt 1)
• but ... missed naked-eye GRB 080319B
  (z0.937)

Gggg
HESS
MAGIC
----------------------------
MAGIC ST
HEVHE data crucial to constrain/unveil emission
mechanism(s)
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GRBs

• 080319B ? missed obs of naked-eye GRB

Intrinsically Nearby z0.937 Brightest ever
observed in optical Exceedingly high
isotropic-equivalent in soft g-rays
Swift/BAT could have observed it out to
z4.9 1m-class telescope could observe out to z17
Missed by both AGILE (Earth screening) and MAGIC
(almost dawn)
next BIG ONE awaited !!
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Galaxy Clusters
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(No Transcript)
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Targets Draco, Willman-I, Segue gals.
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2. DRACO dSph
Milky Way surrounded by small, faint companion
galaxies
Northern source ? MAGIC ok !!

• dSphs ? very DM-dominated objects.

• Distances, M/L ratios 16ltD/kpclt250 kpc,
  30ltM/Llt300

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Draco dSph modeling
d80 kpc
Bergström Hooper 2006
total DM annihil. rate
ltsAvgt, mc WIMP annihil. cross section, mass
g-ray flux
Ng g-rays / annihil.
cusped profile
upper limit
cored profile
g-ray flux
rs 7 0.2 kpc r0 107 109 Mž kpc-3 r02 rs3
0.03 6 Mž2 kpc-3
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_
bb t t
tt-
_
min. cored
WW-
Fermi 1-yr exp.
MAGIC 40-h exp.
max. cusped
ZZ
Bergström Hooper 2006
IACT neutralino detection ltsAvgt ³ 10-25
cm3s-1
unidd GeV sky brightness flucts to be followed
up a TeV energies
Stoehr 2003
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Draco dSph obsd MAGIC arXiv0711.2574
7.8 hr May 2007
m0 gt 2 TeV Wc lt (WDM2dWDM)WMAP0.113 m0 gt 2
TeV Wc lt (WDM-2dWDM)WMAP0.09751
m0 2 TeV Wc lt (WDM2dWDM)WMAP0.113 m0 2
TeV Wc lt (WDM-2dWDM)WMAP0.09751
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Probing Quantum Gravity
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Mrk 501 Jul 9, 2005
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Outlook
GeVTeV wide spectral coverage to observe
Galactic-environment phenomena useful to solve
long-standing issues about CRs. SNRs, molecular
clouds ? HEVHE emission mechanism,

energy-dependent diffusion. GRBs, star-forming
galaxies ? SFR(z) Galaxy clusters ? NT side of
structure formation Pulsars ? measure
magnetosph. emission cutoff AGNs ? solve (SE)SC
model of AGNs measure EBL(z)
probe short-time variability as
function of E simultaneous mwl
monitoring of low-state ToO
obss of high states DM halos ? depending on mc,
decay channels, central density, distance
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Thanks!