You are here:
Foswiki
>
Cosmo Web
>
ToK
>
ToK070215RoughNotes
(revision 1) (raw view)
Edit
Attach
<< Cosmo.ToK %TOC% ---- ---+ ToK Warszawa meeting - Rough Notes Thu 15 Feb 2007 %RED% *These are just rough notes - feel free to correct them, add links, etc.* %ENDCOLOR% ---++ Hector Rubinstein - stockholm - magnetic fields Magnetic fields on kpc scales exist. They may exist on intergalactic scales - it's unclear whether or not their origin is primordial. CMB - Planck - may be able to detect magnetic fields present at the epochs not long after nucleosynthesis and recombination it is well known that photon has a thermal mass - about 10^{-39} [units =eV?] which is extremely small - related to electron loops Maxwell eqns -> Proca eqns WikipediaEn:Proca_action m_photon < 10^-26 eV \exists galactic mag fields at z \approx 3 making dynamo mechanisms difficult to explain them ---++ Boehm - LDM hypothesis ---+++ 511 keV detection Leventhal(sp?) 199x ApJ OSSE 3 components Purcell et al 1997 ---+++ candidates stars - SNe, SNII, WR compact sources - pulsars, BH, low mass binaries - most excluded because they would imply 511keV from the disk - SNIa - need large escape fraction and explosion rate to maintain a steady flux - low mass X-ray binaries - need electrons to escape from the disk to the bulge ---+++ MeV scale dm + dm -> e^- + e^+ e+ loses energy -> positronium e+e- -> positronium decays para-positronium 2 gamma - monochromatic wih 511keV ortho-positronium 3 gamma - continuum ---++++ predictions positron emission should be maximal with highest DM concentration (n^2 effect?) ---++++ cdm spectrum does NOT produce CDM-like power spectrum??? - at 10^9 M_sun essentially CDM-like - by 10^6 M_sun, the difference would be important ---++++ spectrum Ascasibar et al 2005, 2006 ---++++ model * through F- 511keV * through Z' relic density ---+++ link with neutrino mass interaction/decay diagrams -> link between neutrino mass and DM cross section: %$ m_\nu = \sqrt{ \sigma \nu \over 128 \pi^3 } m_N^2 ln{ \Lambd^2/m_N^2 } $% \sigma_\nu well-known for relic density \sim 10^{-26} cm^3/s %$ \Rightarrow m_N < 10 MeV $% to fit neutrino data BBN: 1MeV < m_N ---+++ low energy Beyond SM MeV DM has definitely escaped all previous low energy experiments due to lack of luminosity BABAR/BES II ... ? ---+++ summary ... * explains low value of neutrino masses * detection at LHC may be possible but requires work * back to SUSY -> snu-neutralino-nu ? ---++ Conlon - hierarchy problems in string theory: the power of large volume planck scale 10^18 GeV ... cosm constant scale (10^-3eV)^4 - large-volume models can generate hierarchies thorugh a stabilised exponentially large volume - predicts cosmological constant (but about 50 orders of magnitude too large - solving this problem is left to the reader/audience) ---++ G\"unther Stigl - high-energy c-rays, gamma-rays, neutrinos HESS - correlation of observations at GC with molecular cloud distribution KASCADE - has made observations Southern Auger - 1500km^2 - in Chile/Argentina Hillas plot c-rays at highest energies could be protons, could be ions - most interactions produce pions; pi^\pm decays to neutrinos pi^0 decays to photons (gamma-rays) * origin of very high energy c rays remains one of the fundamental unsolved questions of astroparticle physics - even galactic c ray origin is unclear * acceleration and sky distribution of c rays are strongly linked to the strength and distribution of cosmic magnetic fields - which are poorly known * sources probably lie in fields of \mu-Gauss * HE c-rays, pion-production, gamma-ray/neutrinos - all three fields should be considered together; strong constraints arise from gamma-ray overproduction ---++ Khalil - DM - SUSY - brane cosmology (British University in Egypt = BUE) - friedmann eqn modified in 5D (brane model) - dark matter relic abundance
Edit
|
Attach
|
P
rint version
|
H
istory
:
r2
<
r1
|
B
acklinks
|
V
iew topic
|
Edit WikiText
|
More topic actions...
Topic revision: r1 - 16 Feb 2007,
BoudRoukema
Cosmo
Log In
or
Register
Toolbox
Create New Topic
Index
Search
Changes
Notifications
RSS Feed
Statistics
Preferences
Webs
Cosmo
Main
Sandbox
System
English
Français
Polski
Copyright © CC-BY-SA by the contributing authors. All material on this collaboration platform is copyrighted under CC-BY-SA by the contributing authors unless otherwise noted.
Ideas, requests, problems regarding Foswiki?
Send feedback