raggi cosmici di energia inferiore a 1015 ev - …deangeli/fismod/boezio1.pdf · raggi cosmici...

Raggi Cosmici

Solar System: Lodders, ApJ 591 (2003) 1220 GCR: Israel, ECRS 2004

Raggi Cosmici nella Via Lattea

Vita dei Raggi Cosmici T1 T2

Accelerazione e Sorgenti

Cortesy of E. Amato & P. Blasi

CR PRECURSOR

SUBSHOCK

DENSITY OF ACCELERATED PARTICLES

NON-LINEAR DIFFUSIVE SHOCK ACCELERATION

CR INDUCED B-FIELD AMPLIFICATION DYNAMICAL REACTION OF AMPLIFIED FIELDS ESCAPE OF PARTICLES

UPSTREAM DOWNSTREAM

2 1

U0

U2

0 U1

t

u x

MASS CONSERVATION

t

xu2 Pg Pc Pw

MOMENTUM CONSERVATION

f (t,x, p)

t u (x)

f (t,x, p)

x

xD(x, p)

f (t,x, p)

x

p

3

f (t,x, p)

p

du (x)

dx

TRANSPORT EQUATION

t

u2

2

Pg

g 1

x

u3

2gPgu

g 1

u

xPc Pw Ew

ENERGY CONSERVATION

TWO-FLUIDS: Drury & co. MONTECARLO: Ellison & co. KINETIC: Amato & Blasi 05,06 Blasi et al.08 Caprioli et al 08,09,10,11

DYNAMICAL REACTION OF ACCELERATED PARTICLES

BASIC PREDICTIONS OF NL-DSA

HINTS OF EFFICIENT ACCELERATION: T2 IS LOWER THAN EXPECTED CONCAVE SPECTRA (FLAT AT HIGH ENERGIES) B-FIELD LARGELY AMPLIFIED

UPSTREAM DOWNSTREAM

2 1

U0

U2

0 U1

•DIFFERENT COMPRESSION RATIO AT DIFFERENT ENERGIES DUE TO D(E) •TOTAL COMPRESSION RATIO >4 •COMPRESSION AT SUBSHOCK <4


THEORY CONFRONTS OBSERVATIONS

BUT DO WE OBSERVE ANY OF THESE?

EFFICIENT ACCELERATION

HIGH B FIELD

HIGH PMAX

FLAT SPECTRA


AMPLIFIED MAGNETIC FIELDS

B~100-300G

IN THE SIMPLEST PICTURE

EFFICIENT PARTICLE ACCELERATION BECAUSE OF HIGH B-FIELD

HIGH B-FIELD BECAUSE OF EFFICIENT PARTICLE ACCELERATION

CAVEAT: LARGE MAGNETIC FIELDS MIGHT HAVE DIFFERENT ORIGIN AND DO NOT IMPLY EFFICIENT SCATTERING…

Cas A Tycho

x D(Emax ) loss(Emax )

0.04B1003 / 2pc


H.E.S.S. Highlight: Resolved Supernova-

Remnants

RX J1713-3946

Spectra

Preliminary

Index ~ 2.1 – 2.2 Little variation across SNR Cutoff or break at high energy

Acceleration of

primary particles in SNR shock to well beyond 100 TeV

TeV image by HESS (Aharonian et al. 2007)

Spectrum by Fermi-LAT (Abdo et al. 2011)

GeV image by Fermi-LAT (Abdo et al. 2011)

LEPTONIC EMISSION !

EXAMPLE: SNR RXJ1713.7-3946 TeV is not enough

Π0-dominant

Mixed Π0/IC

Inverse Compton B-Field 10 G

Abdo et al 10

Cas A

e =2.1-2.2

QuickTime™ and a decompressor

are needed to see this picture.

Cosmic Rays & the -ray Sky Giordano et al 11

TYCHO

e =2.2-2.3 NO PEVATRONS AND STEEP SOURCE SPECTRA

Fermi (Abdo et al 09,10,11)

AND Agile (Giuliani et al 10,11)

BUT ARE THESE THE SOURCES OF GALACTIC CRs?

Cosa viene accelerato

First Ionization Potential

Trans-Iron Galactic Element Recorder Two balloon flights over Antarctica: •December 2001 (32 days); • December 2003 (18 days) New ballon flight with significantly larger accpetance (Super-TIGER) in December 2012, talk by J. E. Ward, L7 4, later today

Rauch et al. ApJ 697, 2083 (2009)

Combined results from both flights of TIGER 50 days of data

Fe

Ni

Zn

Ga Ge Se

Sr

Ga is well resolved from Zn, despite ratio ~ 10:1 Fe/Co & Ni/Cu

~ 100:1

Meyer, Drury, & Ellison Ap.J. 487 182 (1997) Preferential acceleration of elements found in interstellar grains, and mass-dependent of acceleration of the volatiles.

(Grains) (Gas)

Meyer, Drury, & Ellison Ap.J. 487 182 (1997) Preferential acceleration of elements found in interstellar grains, and mass-dependent of acceleration of the volatiles.

There is a lot of scatter here when comparing the cosmic-ray source with solar system.

(Grains) (Gas)

10 20 30 40 50 60 70 80 90100

0.1

1

Volatile Refractory

GC

RS/

(80%

SS+

20%

MSO

)

Atomic Mass

Mg

Al

Si

P

Ca Fe

Co

Ni

Sr

NNe

S Ar Cu

Zn

Ga

Ge

Se

Refractories

Volatiles

6.9.10_Figure_for_MHI/TIG_GCRS_vs_80-20mix_rev2

Now compare GCR source abundances with a mixture of 80% SS (Lodders) and 20% Massive Star Outflow (Woosley & Heger).

Rauch et al. ApJ 697, 2083 (2009)

Preliminary results of ACE-CRIS for elements Z>28 give results similar to TIGER.

Propagazione dei raggi cosmici

Misure isotopiche

Cosmic Ray Isotope Spectrometer (CRIS) Identifica isotopi Li-Zn ~50 – 500 MeV/nucleone

Misure Isotopiche

Cosa viene accelerato da SN

59Ni + e -> 59Co T1/2 = 0.76 x 105 anni decadimento β is energeticamente proibito ed il nucleo 59Ni è stabile. Durante la fase di accellerazione i nuclei sono strippati di tutti i loro elettroni. Quindi, visto che il 59Ni è assente dai Raggi cosmici misurati a terra devono essere intercorsi più di 105 anni tra nucleosintesi ed accellerazione. Perciò si può concludere che il materiale accellerato dalle SN proviene dal mezzo interstellare adiacente. Importante notare, però, che questo è sperimentalmente provato solo per la componente di bassa energia dei CR.

Propagazione dei CR nella Galassia

From J. Ormes, ECRS 2004

Tempo di confinamento nella Galassia

β-decay secondaries 10Be 1.5 Myr 26Al 0.71 Myr 36Cl 0.30 Myr 54Mn ~0.68 Myr (stima teorica del decadimento β, in laboratorio decade per cattura elettronica)

15.0±1.6 Myr

Yanasak et al., ApJ, 563 (2001) 768

Propagazione nella Galassia

Yanasak et al., ApJ 563 (2001) 768, n=0.34 cm-3

Molnar & Simon, 27th ICRC 1860, n=0.23 cm-3

Moskalenko & Strong, Ap&SS 272 (2000), 247, H=4 kpc

Hams et al., 27th ICRC, 1655

Assieme alla misura su B/C, la frazione dell’isotopo 10Be (10Be/9Be) può essere usata per determinare dei parametri dei modelli di propagazione dei raggi Cosmici nella Galassia

Eliosfera e Modulazione Solare

Bow Shocks

500 AU

250 AU

Heliospace: The Heliosphere

Voyager 1: Dec 2004

Voyager 2: Aug 2007

• Launched in 1977

• Voyager 1: ~ 121 AU

• Voyager 2: ~ 99 AU Cortesy of M. Potgieter

http://www.nasa.gov/centers/goddard/images/content/96468main_galaxy4_lg_web.jpg

http://www.nasa.gov/centers/goddard/images/content/96451main_2002-05-a_lg_web.jpg

The Solar Wind

Strong latitude dependence at solar minimum

Cortesy of M. Potgieter

Sunspot Numbers

0

20

40

60

80

100

120

140

160

180

200

1600 1650 1700 1750 1800 1850 1900 1950 2000

Year

Num

ber o

f Spo

ts

Maunder Minimum

Dalton Minimum

Solar Activity and Sunspot Numbers

11-year cycles


Wavy Heliospheric Current Sheet

Kota, 2010

Conceptual wavy HCS


Tilt angle of the HCS: good proxy for solar activity, determined with solar magnetograms and

appropriate modelling

Maximum solar activity

Minimum solar activity

The wavy heliospheric current sheet (HCS)

Moderate solar activity


Solar Activity and Cosmic Rays


Cosmic rays as indicators of heliospheric conditions Modulation of galactic CRs at Earth at NM energies (E > 10GV)


1

3 ln

Df f Q( r, p,ff t

t p)f

K VV v

Time-dependent, pitch-angle-averaged distribution function Diffusion Convection with solar wind Particle Drifts Adiabatic energy changes Any local source

Parker (Planet. Space Science, 13, 9,1965)

Transport equation for the transport, modulation and acceleration of cosmic rays in the heliosphere

Second order Fermi acceleration

22

pp1 f... ... p D

p pp


Drift direction of electrons in A > 0 cycle

Drift direction of electrons in A < 0 cycle

Charge-sign dependent modulation


Gradient, curvature and current sheet global drift patterns

Strauss, 2009

qA > 0 qA < 0

Positively charged CRs Cortesy of M. Potgieter

Modulation of galactic electrons and positrons at solar minimum

Electrons Positrons

Langner & Potgieter, Solar wind termination shock and heliosheath effects on charge-sign dependent modulation for protons and anti-protons, JGR, 109, 2004; Potgieter & Langner, Heliospheric modulation of cosmic ray positrons and electrons: Effects of the heliosheath and solar wind termination shock, ApJ, 602, 2004.


Ratio of Electrons to Positrons At Earth vs. LIS

Solar minimum modulation Two consecutive magnetic field

polarities

Ratio of Protons to Anti-protons At Earth vs. LIS

Solar minimum modulation Two consecutive magnetic field

polarities

Modelling results for galactic electrons, positrons, protons & anti-protons at Earth

Langner & Potgieter, 2003 Cortesy of M. Potgieter

Modeling of galactic electrons in the heliosphere

Voyager 1 galactic electron observations (Private Comm W. R. Webber, May 2011)

Computed electron spectra at different radial distances

Kinetic Energy (GeV)

10-3 10-2 10-1 100 101 102

Diff

eren

tial i

nten

sitie

s (p

artic

les

m-2

s-1

sr-1

MeV

-1)

10-6

10-5

10-4

10-3

10-2

10-1

100

101

102

103

104

RRN LIS1 AU5 AU60 AU90 AU110 AUPAMELA 2008Ulysses 1997Evenson 1983Voyager 1 2010

E -1.5

Voyager 1

Galactic electron spectrum at the HP seems to consist of two power laws…!

E–(3.09 ± 0.06)

PAMELA


Modulation of cosmic ray protons: mid 2006 to end of 2009


Protons Electrons

Protons

Electrons

Evidence of charge-sign-dependent modulation from 2006-2009 from PAMELA…!


CR modulation in the Heliosphere

mid 2006 to end of 2009: Modeling

Magnetosfera Terrestre

Proton flux at various cutoffs

•Grigorov, Sov. Phys. Dokl. 22, 305 1977 •NINA ApJ Supp.132 365, 2001 •AMS Phys. Lett. B 472 2000.215,

Phys. Lett. B 484 2000.10–22 •Lipari, Astrop. Ph. 14, 171, 2000 •Huang et al, Pys Rev. D 68, 053008 2003 •Sanuki et al, Phys Rev D75 043005 2007 •Honda et al, Phys Rev D75 043006 2007

Atmospheric neutrino contribution Astronaut dose on board International Space Station Indirect measurement of cross section in the atmosphere nell’atmosfera Agile e Glast background estimation

--- M. Honda, 2008

Pamela World Maps: 350 – 650 km alt

36 MeV p, 3.5 MeV e-

Pamela maps at various altitudes

Altitude scanning

SAA

SAA morphology

Latit

ude

Alti

tude

Altitude

Longitude

Neutron rate

South-Atlantic Anomaly (SAA)

raggi cosmici di energia inferiore a 1015 ev - …deangeli/fismod/boezio1.pdf · raggi cosmici...

Documents