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Summary Talk by Arnon Dar. Dedicated as a tribute to Jean Tran Thanh Van and Kim who step aside after initiating and organizing the past 44 Rencontres de Moriond in order to promote scientific collaboration and spread scientific knowledge beyond borders and ideological and racial barriers.

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slide1

Summary Talk byArnon Dar

Dedicated as a tribute to Jean Tran Thanh Van and Kim

who step aside after initiating and organizing the past 44 Rencontres de Moriond in order to promote scientific collaboration and spread scientific knowledge beyond borders and ideological and racial barriers

slide2

Highlights on some key results presented in this conference

in three major areas

and on some observations relevant to life on planet Earth

Observing the Universe with High Energy Gamma Ray- Cosmic Ray- and Neutrino Telescopes.

Understanding and Modeling the High Energy Cosmic Sources and Their Observed High Energy Emissions .

Recent Signs From Astrophysics And Cosmology On New Physics

slide3

UHECR Physics Issues:

● Does a high-energy suppression exist? Is it due to the GZK effect?

● What are the extragalactic sources?

● What is the cause of the ankle?

● Is the ankle accompanied by a composition change?

● Where is the galactic-to-extragalactic transition in the spectrum

and perhaps in composition?

● What is the cause of the second knee?

(J. Belz, HiRes)

GZK

slide4

What are the extragalactic sources?

PAO: AGN TRACERS OF UHECRs SOURCES

– Θmax = 3.1°

– Emin = 56 EeV

– Zmax = 0.018

Abrahams et al., Science 318, 938 (2007),

Astroparticle Physics 29, 188 (2008):

Association by chance: P = 0.0017

THE BIRTH Of UHECRs ASTRONOMY ?

slide5

HiRes Search, PAO Criteria

θmax = 3.1°

Emin = 56 EeV

zmax = 0.018

Cen A

M87

Correlation seen in 2/13 events > 56 EeV

3.2 expected randomly

P = 83% No Effect

The ‘Birth of UHECRs ASTRONOMY’ not confirmed by HiRes

slide6

What is the cause of the ankle?

Fabian Schüssler, KIT, Karlsruhe, Germany

Denis Allard

APC, CNRS/Université Paris 7

The composition is getting heavy at the highest energies ?

The ankle can be pair production dip in the extragalactic flux due to the energy and Z dependence of the pair production Xsection

Realistic calculations must include diffusion of CRs below the knee into the Galaxy

slide7

● Is the ankle accompanied by a composition change

● Where is the galactic-to-extragalactic transition in the spectrum

and perhaps in composition?

Comparison between HiRes and PAO

Hires

knee

slide8

UHERs - Conclusions

1. Allowing for a 10% adjustment in the relative normalization,

HiReS and PAO measure a similar spectrum of UHECRs

2. HiReS does not confirm the `birth of UHECR Astronomy

claimed by PAO (Arrival directions correlated with

nearby AGN)

3. HiRes find a change in composition around the CR ankle

to pure proton composition. PAO finds a significant

fraction of nuclei above the CR ankle which increases with

energy.

More Statistics/analysis are Needed to Resolve these Discrepancies

slide12

Explosion of VHE Gamma Ray Sources

More than 80 VHE sources known,

and the number is keeping increasing.

Diverse population of VHE sources:

Galactic: Pulsars, SNR/PWNs, Binaries, Microquasars, OB Associations

Extragalactic: Radio Galaxies, Blazars, BL-LACs (12 confirmed sources)

But:

No -ray signal from galaxy clusters found (yet)

– Upper limits by EGRET, HESS, VERITAS

No TeV -ray signal from GRB found (yet)

Wystan Benbow, Harvard-Smithsonian Center for Astrophysics

slide13

Fermi so far:

~21 young radio pulsars

~15 new young pulsars

~9 MSPs

Fermi-LAT pulsar detections

(L. Guillemot)

MSPs = pink dots. All of them are Galactic field sources.

(close sources => appear outside of Galactic plane)

slide14

limits on the EBL density

The spectrum of Quasar 3C279 (z=0.536) the most distant detected (MAGIC) VHE γ-ray source put strong limits on the EBL density suggesting an EBL on the level of galaxy count

Daniel Mazin

slide16

Dark Matter or Modified Gravity (e.g. MOND) ?

Evidence for DM from two Cosmic Supercolliders

the "BulletCluster" 1E0657-56 and MACSJ0025-1222

Total Mass

Gas

Total Mass

Galaxies observed Optically

Hot Gas Observed by X-ray Emission

Total Mass Maped by Weak Gravitational Lensing

Maruša Bradač (UCSB)

slide18

PAMELA is the first space experiment which ismeasuring the antiproton and positron cosmic-ray components to the high energies (100 GeV) with an unprecedented statistical accuracy.

Antiproton to Proton Ratio

Positron Fraction

F.S. Cafagna, XLIV Recontres De Moriond, La Thuille 7th Feb. 2009

slide19

Positron Fraction

Pulsar Component

Atoyan et al. 95

Pulsar Component

Yüksel et al. 08

Pulsar Component

Zhang & Cheng 01

Secondary production

Moskalenko & Strong 98

slide20

If PAMELA positron ratio is correct:

½ ?

Dark matter fingerprints ?

CR propagation from nearby SNe ?

(spiral arm SNe: Piran+Shaviv)

Moskalenko & Strong 1998

slide21

Consistent with charge sign-dependent solar modulation.

In the region of interest PAMELA and HEAT are completely consistent with each other.

Caution: Misidentified CR p’s ?

Michael Schubnell:

HEAT- e± was first to employ powerful particle ID

(rigidity vs. TRD vs. EM shower development)

Resulting in improved hadron rejection ( ).

slide22

Near Future Results on Electron Spectrum:

PAMELA & FERMI (GLAST) (taking data in space);

ATIC-4 (had successful balloon flight, under analysis);

CREST (new balloon payload under development);

AMS-02 (launch date TBD);

CALET (proposed for ISS);

ECAL (proposed balloon experiment).

Positron/ Electron Separation: PAMELA & AMS-02

slide23

Significant enhancement in the e flux around E ~ 600 GeV?

Anihilation of ~ 600 GeV WIMP? (Extra dimension extension of the particle SM) ?

Undiscovered extremely nearby astrophysical sources (Pulsars?) ?

ATIC 2001 & 2003

Michael Schubnell

University of Michigan

electron Knee ?

slide24

1. The ATIC excess of electrons around 600 GeV implies a bump in the diffuse GBR around 1 GeV due to inverse Compton scattering (ICS) of the MBR which is not seen in the LAT data. (The largest enhancement should be observed at large latitudes where hadronic production of photons (via is strongly reduced relative to ICS.)

2. The CB model of CR acceleration in Galactic GRBs

(mostly pointing away from us) predicted a CRe `knee’ at,

as observed by H.E.S.S.

slide25

NO GEV EXCESS IN THE DIFFUSE GBR

Guolaugur Johannesson (Stanford)

 The EGRET GeV excess is not seen with the LAT.

The measured intermediate latitude γ-ray spectra can be explained by cosmic ray propagation models based on the locally observed spectrum of

cosmic-ray nuclei and electrons.

 No GeV excess  No evidence for GeV gammas from dark matter anihilation

slide26

Not so good news for nu Astronomy

No -ray signal from galaxy clusters found (yet)

– Upper limits by EGRET, HESS, VERITAS

Dalibor Nedbal, Wilfried Domainko

Charles University, Prague

Intracluster HE neutrinos:

 No detectable flux of intracluster HE neutrinos

No TeV -ray signal from GRB found (yet)

 No detectable flux of TeV neutrinos from GRBs

TeV Gamma Fluxes Suggest Too Small Fluxes

to be Detected with current nu Telescopes

slide27

The GRB Debate

-------------------------------------------------------------------------------------------------------------------ISSUE Majority View Minority View Observational Verdict (Year)

-------------------------------------------------------------------------------------------------------------------

Origin Man made Nature PhenomenaVela Satellites 1967-1972

Place Solar System Outside Solar System (by Triangulation) 1967- 1973

Galactic Disk Cosmological - CGRO1973-1992

Large Galactic halo Ditant Galaxies BeppoSAX , HST, GBTs1997

Mechanism Relativistic Fireball Relativistic JetsCGRO, BeppoSAX 1992-1999

Producer n*-n* Merger SN ExplosionBeppoSAX , HST, GBTs 1998-2003

Radiation SR ICS BeppoSAX+Swift 1999-2008

-------------------------------------------------------------------------------------------------------------------

On-going debate (no concenus) :

Jets Conical Thin Shells Cannonbals Swift , HST, GBTs

Composition Ordinary Matter

Source Hypernova SN Type Ib/c (and II ?) HST, GBTs

SN –GRBs Small fraction of SN Perhaps all SNIb/cIntegral

Radiation SSC ICS of glory light Swift,Fermi

Remnant BH, Magnetar n* or BH Swift , Fermi HST, GBTs

Fermi

slide29

SHB081024

SHB with >1 GeV

Delayed HE emission

longer than the SHB

  • The delay of the HE emission seems to be a common feature of the GRBs observed by the LAT so far.

Jonathan Granot

slide30

CosmicThreats

SN1054

FromGamma Ray Bursts

and Cosmic Ray Bursts:

Supernova Explosions

The Crab Nebula. Light from 6500 light years reached Earth first in 1054.

Merger of Compact Stars

Collapse of Compact Stars

Mass Accretion onto Compact Stars

Cosmic Ray flux Modulation by :

The largest ever recorded solar flare. EUV SOHO image.

(global warming)

Solar Activity

Solar system passage through Spiral Arms

Terrestrial Loss of Magnetic Shield

slide31

GRB 080319B's X-ray afterglow

GRB 080319B's optical afterglow

Swift’s X-ray image of GRB 080319B

GRB 080319B

Was billion times more luminous

than ordinary supernovae and the

most distant object (6.5 billion year look-back time) which could be seen by the naked eye .

slide32

The Galactic Monster Eta Carinae

Eta Carinaeis currently the most massive star with the highest confirmed luminosity in the Galaxy at a distance of 7500 Ly from the sun. It had a giant eruption in 1843, and within a few years it emitted as much light as a supernova, faded and re-brightened recently. It may explode in a supernova or an hypernova (SN like SN 2006gy, 238 million Ly from Earth) and produce a GRB within the next millenia or even in a few years (like SN 2006jc at 77 million Ly away which erupted in almost an SN size explosion two years earlier).

Placing GRB 990123 or GRB 080319B at 7500 Ly from Earth:

2

Equivalent to ~100 million one-kt A-bombs distributed uniformly (one per km )

at the top of the atmosphere, over the entire hemisphere facing Eta Carinae, and exploding simultaneously.

Imminent Catastrophe ?

slide33

Will Eta Carinae end in a supernova explosion ?

-Yes, probably in a hypernova=super supernova (like SN 2006gy, at 238 million Ly from Earth)

Will Eta Carinae Produce a GRB?

-Yes, but probably beamed away from us, and I better be right!

Pointing direction:

away from Earth

Cannonball

model :

Fireball

model

Beam’s

opening

angle:

Beam’s

opening

angle:

EARTH

UNSAFE?

EARTHSAFE!

slide34

Indirect Evidence forBeaming from GRB light curves

Breaks have different

origin in the FB and

the CB models. The

estimated opening angle of the GRB is model dependent.Light curves with/

without breaks are

reproduced well

by the CB model, but

not by the FB model!

`Break’

cannonballs fired by sn1987a
Cannonballs fired by SN1987A

Nisenson & Papaliolios,ApJ, 518, L29 (1999)

ApproachingCB

(superluminal)

Release:

SN1987A

Converted to Energy

of a Cosmic Ray Beam

and a Gamma Ray Burst

RecedingCB

slide39

Tree Rings:

Proxy of atmospheric CO2 level: CO2 content*

Proxy of cosmic ray flux: C14 content**

Proxy of the solar cycle duration***

Earth temperture is correlated with cycle duration:

** Carbon-14 is created in n+N14  p+C14 by neutrons produced in cosmic ray showers in the upper atmosphere