1 Additional observable evidences of possible new physics Lecture from the course “Introduction to Cosmoparticle Physics”

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Additional observable evidences Additional observable evidences of possible new physicsof possible new physics

Lecture from the course

“Introduction to Cosmoparticle Physics”

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0. Remembering of the learned material0. Remembering of the learned material

• Baryonic asymmetry of Universe

• Evidences in favour of dark matter

• Reasons for inflation

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1. Cosmic rays of middle and high energy1. Cosmic rays of middle and high energya) common information

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6

eV/cm5.0~

pc,1003~Oe,10)53(~

H

inhomGal LH

UHECR (EAS)

Interstellar medium:

3

3

3

eV/cm26.0

eV/cm5.0~

eV/cm5.0~

rel

light

CR

“Natural” sources:

SN, pulsars, secondary origin

Problems:

sources, parameters of interstellar medium and halo, solar modulation

THERE ARE MANY UNCERTAINTIES

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1. Cosmic rays of middle and high energy1. Cosmic rays of middle and high energyb) diffuse gamma-radiation

?

???

From GC

From high latitude

there is unexplained -background

Most conservative predictions are used.

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1. Cosmic rays of middle and high energy1. Cosmic rays of middle and high energy

c) antiprotons

eV10~10)301(103300~300 1716196 HRpc diffusive propagation

years10~)s

cm10~kpc,10~(2 8

22928 DD

Secondary origin:

ApXXA

A

ApkinApppp

AAA

A

mmms

mmsE

mEmmEmss

msV

VVV

VpEE

2,2

2)22()(,4

)(1

22*

max

222

*

2

*max

*max

min

p

AAkin

p

pA

m

mE

m

mm 2

min

2

2

)(

Apkinpkin mEE 2atat

Dipping of the spectrum at low energy

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c) antiprotons

?

c1) antideuterium


Expected secondary antiD

Hypothetical primordial antiD (from PBH)

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d) positrons

E>0.1 GeV synchrotron and Compton losses of energy

2/1

0

22928

0

02/1

0

0

9

2

2

GeVkpc~,

s

cm10~~

)(~),(2~

1,

1)(

GeVyear

1103)(

9

32,)(

00

EfewaEEDEd

Eb

DDdtEEDt

Et

tE

EtE

m

rEEb

dt

dE

E

E

E

E

rellightHe

e

!

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d) positrons

?


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e) possible origin

Besides “natural” astrophysical origin, CR can originate from annihilation or/and decay of dark matter particles in halo of our Galaxy, or evaporation of PBH.

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2. Cosmic rays of ultra high energy2. Cosmic rays of ultra high energyContent, propagation, origin of UHECR are the subject of modern investigations.

Anisotropy of UHECR does not allow to identify sources (to connect with our Galaxy or other galaxies).

At UHE many known particles should experience energy losses.

Macroscopic magnitudes of the energy!

0.2

182 eV10sryearkm

100~)(

EEI

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2. Cosmic rays of ultra high energy2. Cosmic rays of ultra high energy

peeNp relCR ,a) protons and nuclei

eV1032~)K7.2(~10~70.2~~

eV105~eV1032

MeV140GeV90~

2)cos1(2)(

3(max)

193

2222

-

-

pp

ppppp

.TTTEEfewaE

.

.

E

mmE

mmmmEEmpps

0 2 4 6 8 10ET

0.1

0.2

0.3

0.4

NdEd

Spectrum in case of homogeneous distribution of sources

Spectrum in case of all sources are concentrated in Local Cluster (within 20 Mpc)

Ene

rgy

loss

rat

e

Greisen-Zatsepin-Kuzmin cut-off

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eebackgrCR b) gamma c) electrons and positrons

Abs

orpt

ion

prob

abili

ty

Ene

rgy

loss

rat

e

ee backgrCR (See also slide 7.)

Galactic scale

Universe scale

Galactic scale

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d) possible origin

Magnetosphere of pulsars

Accretion disk

Cosmic strings

Decay or annihilation of hypothetical supermassive relic particles in extensive halo

UHE neutrino mediation: Fargion mechanism

anisotropy in Galaxy

- homogeneously in Universe

GUTUHEsource

UHEZ

UHE

ZUHErelUHE

EzEm

mE

mmEpps

~)1(eV10eV5.02

GeV)91(~

2

2)(

)(2222

22

- isotropic

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3. Gamma-bursts3. Gamma-bursts

s1001.0~

cmserg1010~keV100010~ -2-137

t

IE

G10)103(~ 12B

Gamma-ray bursts (GB) are discovered in 1973, and after launching interplanetary stations they are observed with frequency 1 per day.

Their typical characteristics:

In some gamma-bursts a broad absorption lines are observed at E~30-100 keV. It can be treated as a resonant absorption by plasma in magnetic field with

Moreover, sometimes emission lines at E≈400±50 keV are observed. It can be treated as a e+e--annihilation in gravitational field with

23.0~ c

These led to conclusion that gamma-bursts can be connected with neutron stars, energy release of GB is estimated as ~1039-40 erg.

Short time (t~0.01-0.1s) variability of some gamma-bursts tells about compact size of the source: ~tc~3000 km

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3. Gamma-bursts3. Gamma-burstsHowever, no gamma-bursts were identified with visible sources. Moreover, GB events are distributed on the celestial sphere isotropically.

In the end of 1990s, there appeared event of GB which has been identified with a distant galaxy at z~1! Energy release of GB might be, in case of isotropic source, ~1052-54 erg! (GRB 990123, z=1.6, 1.4·1054 erg)

For comparison: novae – 1045-46 erg, supernovae – 1050-51erg (in the maximum ~1042 erg/s).

possible origin

Cosmic strings (mainly, for short time GB; problematic connection with galaxy), binary NS merger, SN (poor quantitative predictions), ???

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4. Difficulties of Cold Dark Matter scenario4. Difficulties of Cold Dark Matter scenario

1) .An excessive number of dwarf galaxies are predicted: e.g. in Local Group a ratio between giant and small galaxies is ~1:10, while CDM model predicts ~1:100.

2) “Cusp”-crisis: analytic calculations, “N-body” simulations in framework of CDM model give a singular central density distribution of dark matter halos (galaxies) in contradiction to observations.

kpc3010~

,/1

0,/1)(

0

03

05.14.0

R

rRr

Rrrr

Possible solution:

a) self-interacting DM particles (free traveling length is ~galactic size)

b) annihilating DM particles (a specific behavior of annihilation cross section is required to provide a small value in early Universe and large one on the galactic stage)

c) complicated dynamics in GC (several massive black holes, …)

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4. Difficulties of Cold Dark Matter scenario4. Difficulties of Cold Dark Matter scenario

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33232

cm10~

GeV/cm10~10~

Sun

clumpoutsideclumpinside

M

MR

3) Clumpiness: Existence of small scale inhomogeneities (clumps) are predicted for CDM. Clumps form on pregalactic stage (of structure formation in Universe) and most of them are destroyed in galaxies. In modern epoch, about 10-(2-3) mass of galaxies can be in form of clumps.

Characteristics of the clumps as predicted:

Consequences: amplification of annihilation (in ~10-100 times).

SunMM 8min 10~

Mmin depends on type of DM particle.

For neutralino typically:

4) Caustic rings: Dynamics of contraction (infall) of CDM into Galaxy leads to an existence of flows of CDM of spherical form and increased density.

Documents

1 Additional observable evidences of possible new physics Lecture from the course “Introduction to Cosmoparticle Physics”