Implication of e ± and pp cosmic ray spectra on properties of dark matter

HTML
DOWNLOAD

Wielkość: px

Rozpocząć pokaz od strony:

Download "Implication of e ± and pp cosmic ray spectra on properties of dark matter"

Renata Kamińska
7 lat temu
Przeglądów:

1 Implication of e ± and pp cosmic ray spectra on properties of dark matter F. JEGERLEHNER Uniwersytet Śla ski, Katowice DESY Zeuthen/Humboldt-Universität zu Berlin Seminar, October 14, 2008, University of Silesia, Katowice supported by the Alexander von Humboldt Foundation

2 Outline of Lectures: 1 Pamela experiment 2 Pamela data and dark matter properties 3 Dark matter (general remarks)

3 PAMELA mission: magnetic spectrometer on satellite Italian-Russian cosmic ray experiment Preliminary PAMELA data analyzed in M. Cirelli, M. Kadastik, M. Raidal, A. Strumia, arxiv: [hep-ph].

4 (i) Preliminary PAMELA data show dramatic increase in e + /(e + + e ) spectrum in cosmic rays above 10 GeV [compatible with less sensitive HEAT and AMS-01 results] (ii) no excess in p/p compared with predicted background (iii) at low energy E e + < 10 GeV positron flux is suppressed by present solar magnetic polarity (iv) observed also (e + + e ) excess in balloon experiments PPB-BETS and ATIC-2 with sharp cut-off just below 1 TeV Main assumption: excess is due to DM annihilation into SM particles: DM + DM e + e,, q q, W + W,, h + Note: DM annihilation into W, Z, h and quarks produces p, which appears not to be enhanced Excess could as well be due to astrophysical sources like nearby pulsars! DM assumed some elementary particle: spin 0,1/2,1 and M m m any SM particle mass (non-relativistic limit)

5 Fits of e + (left), e + + e (center), p (right) data. Galactic DM profiles and propagation models are varied to provide the best fit DM with M 150 GeV that annihilates into W W Positron fraction 30 PAMELA 08 preliminary background? Positron energy in GeV E 3 e e cm 2 sec GeV ATIC2 PPBBETS08 EC Energy in GeV pp PAMELA 08 background? p kinetic energy in GeV Fit for M = 150 GeV excluded by p background?

6 DM with M 1 TeV that annihilates into Μ Μ Positron fraction 30 PAMELA 08 preliminary background? Positron energy in GeV E 3 e e cm 2 sec GeV ATIC2 PPBBETS08 EC Energy in GeV pp PAMELA 08 background? p kinetic energy in GeV Fit for M = 1 TeV favored by data background?

7 DM with M 10 TeV that annihilates into W W Positron fraction 30 PAMELA 08 preliminary background? Positron energy in GeV E 3 e e cm 2 sec GeV ATIC2 PPBBETS08 EC Energy in GeV pp PAMELA 08 background? p kinetic energy in GeV Fit for M = 10 TeV disfavored by the current e + + e excess background?

8 If data real and DM annihilation responsible for observed spectral excesses: two solutions singled out 1) a heavy DM (M> 10 TeV) [WIMP] that annihilates predominantly into W W pairs 2) a DM which annihilates predominantly into SM leptons, with no strong dependence on the DM mass Note: should balloon experiment (e + + e ) excess not be confirmed by ATIC-4 and/or GLAST 2) would be ruled out, with 1) as the only possibility

9 Dark Matter some history: Fritz Zwicky 1933 investigates Coma Cluster [cluster of galaxies]: 1) Luminous mass M B (B= brightness) 2) Virial theorem mass finds M tot = 160 M B [first time virial theorem used] at that time M B estimated by far two low [factor should be about 9] Virial theorem: kinetic energy = potential energy M tot 2 R totv 2 G v mean average velocity of objects; R tot overall extension of system Beginning of 1970 s: hidden mass could explain many not understood observations like motions of stars within galaxies [velocity profiles]

10 Solar planets rotation profile F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

11 Milky Way rotation profile F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

12 Rotation curves of NGC4736 and NGC3198 F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

13 Dark Matter in Galaxies 10 : 1 Invisible Halo Visible Galaxy F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

14 Thermal Fluctuations in Cosmic Microwave Background (encodes cosmic history)

15 Acoustic Peaks disentangling comic parameters F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

16 Acoustic Peaks WMAP etc results F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

17 3 Supernova Cosmology Project No Big Bang Knop et al. (2003) Spergel et al. (2003) Allen et al. (2002) 2 Supernovae 1 Ω Λ 0 Clusters CMB expands forever recollapses eventually closed -1 open flat Supernova counts, CBM and the Cosmological Constant Ω M

18 Matter as distributed in our Universe F. Jegerlehner Institut Fizyki, Uniwersytet Śla ski, Katowice Oct 14, 2008

19 Density of Baryonic matter form Nucleon-Synthesis of light elements and CMB temperature fluctuation spectrum (see above) yield same result

20 What is DM? Presently unknown! mass, spin, couplings, etc. Cold Dark Matter (CDM) candidates: only exist in extensions of the SM, typically Weakly Interacting Massive Particle (WIMP) Well known possibility: SUSY together with R-parity s-particles can be pair produced only must exist a Lightest Supersymmetric Particle (LSP) [lightest neutralino=majorana particle of spin 1/2, neutral partners of SUSY partners of Higges and gauge bosons] exists heavy neutral stable state, which is able to cluster (clumping and forming halo of galaxies) Very interestingly: M. Cirelli, M. Kadastik, M. Raidal, A. Strumia paper suggests that cosmic ray spectra of positrons, electrons, anti-protons and protons could give a clue to discriminate between different cold dark matter candidate scenarios! Dark Energy=??? another story (cosmological constant, negative pressure state?)

Podobne dokumenty

Ciemna Materia. Niewidzialna materia, oddz. tylko grawitacyjnie

Ciemna Materia. Niewidzialna materia, oddz. tylko grawitacyjnie Ciemna Materia 1933 r. - Fritz Zwicky, gromada COMA. Pr"dko#$ obrotu galaktyk wokó! wspólnego #rodka masy zbyt du%a aby mog!y one tworzy$ uk!ad zwi&zany. coma Lata 70,80 krzywe rotacji galaktyk; halo niewidzialnej