Changeset 6735

Timestamp:

03/04/05 08:42:44 (20 years ago)

Author:

hbartko

Message:

*** empty log message ***

Location:

trunk/MagicSoft/GC-Proposal

Files:

• Changelog (modified) (1 diff)
• GC.tex (modified) (3 diffs)

trunk/MagicSoft/GC-Proposal/Changelog

@@ +1 @@
+2005/03/04 Hendrik
+* GC.tex:
+  spell check, some new text about DM
 
 2005/03/03 Hendrik

trunk/MagicSoft/GC-Proposal/GC.tex

@@ -154 +154 @@
 
 
-High energy gamma rays can be produced in the GC in the non-thermal radio filaments by high-energy leptons which scatter background infrared photons from the nearby ionized clouds \cite{Pohl1997,Aharonian2005}, or by hadrons colliding with dense matter. These high energy hadrons can be accelerated by the massive black hole \cite{GC_black_hole}, associated with the Sgr A$^*$, supernovae or an energetic pulsar. Alternative mechanisms invoke the hypothetical annihilation of super-symmetric dark matter particles (for a review see \cite{jung96}) or curvature radiation of protons in the vicinity of the central super-massive black hole \cite{}.
+High energy gamma rays can be produced in the GC in the non-thermal radio filaments by high-energy leptons which scatter background infrared photons from the nearby ionized clouds \cite{Pohl1997,Aharonian2005}, or by hadrons colliding with dense matter. These high energy hadrons can be accelerated by the massive black hole \cite{GC_black_hole}, associated with the Sgr A$^*$, supernovae or an energetic pulsar. Alternative mechanisms invoke the hypothetical annihilation of super-symmetric dark matter particles (for a review see \cite{jung96}) or curvature radiation of protons in the vicinity of the central super-massive black hole \cite{GC_black_hole}.
 
 
@@ -183 +183 @@
 The presence of a Dark Matter halo of the Galaxy is well established by stellar dynamics \cite{Klypin2002}. At present, the nature of Dark Matter is unknown, but a number of viable candidates have been advocated within different theoretical frameworks mainly motivated by particle physics (for a review see \cite{jung96}) including the widely studied models of supersymmetric (SUSY) Dark Matter \cite{Ellis1984}. Also models involving extra dimensions are discussed like Kaluza-Klein Dark Matter \cite{Kaluza_Klein}.
 
-The supersymmetric particle dark matter candidates might self-annihilate into boson or fermion pairs yielding very high energy gammas in subsequent decays and from hadronisation. The gamma flux above an energy threshold per solid angle is given by:
+The supersymmetric particle dark matter candidates might self-annihilate into boson or fermion pairs yielding very high energy gammas in subsequent decays and from hadronisation. The gamma flux above an energy threshold $E_{\mathrm{thresh}}$ per solid angle $\Omega$ is given by:
 
 \begin{equation*}
@@ -190 +190 @@
 
 
-where ... is ... . The flux prediction depends on the choose of SUSY parameters and the spatial distribution of the dark matter. The spectra of the produced gamma radiation has a very characteristic feature a sharp cut-off at the mass of the dark matter particle. Also the flux should be absolutely stable in time.
-
-Numerical simulations of cold dark matter \cite{NFW1997,Stoehr2002,Hayashi2004,Moore1998} predict universal DM halo profiles with density enhancement in the center of the dark halos. In the very center the dark matter density can even more enhanced through an adiabatic compression due to the baryons  \cite{Prada2004}. All dark matter distributions that predict observable fluxes are very cusped yielding a point-like source.
-
-Using fits of these dark matter profiles to the rotation data of the milky way predictions for the gamma flux from SUSY particle dark matter annihilation can be made \cite{Fornego2004,Evans2004}. 
+where $\langle \sigma v \rangle$ is the thermally averaged cross section, $m_{\chi}$ the mass and $\rho_{\chi}$ the spatial density distribution of the hypothetical dark matter particles. The flux prediction depends on the choose of SUSY parameters and the spatial distribution of the dark matter. The spectra of the produced gamma radiation has a very characteristic feature a sharp cut-off at the mass of the dark matter particle. Also the flux should be absolutely stable in time.
+
+Numerical simulations of cold dark matter \cite{NFW1997,Stoehr2002,Hayashi2004,Moore1998} predict universal DM halo profiles with density enhancement in the center of the dark halos. In the very center the dark matter density can even more enhanced through an adiabatic compression due to the baryons \cite{Prada2004} present. All dark matter distributions that predict observable fluxes are cusped yielding an approximately point-like source.
+
+Using fits of these dark matter profiles to the rotation data of the milky way predictions for the density distribution of the dark matter can be made \cite{Fornego2004,Evans2004}. Assuming parameters for the SUSY models determine the neutralino mass, the thermally averaged annihilation cross section and the gamma yield. Combining both models about the dark matter distribution and SUSY predictions for the gamma flux from SUSY particle dark matter annihilation are derived.
 
 Figure \ref{fig:exclusion_lmits} shows exclusion limits taking the sensitivity of MAGIC from MC simulations into account. Due to its relative vicinity the Galactic Center yield the largest expected flux from particle dark matter annihilation. Nevertheless this flux is more than one order of magnitude below the current MAGIC sensitivity. Also the observed flux from the HESS experiment way above the theoretical expectation.