Changeset 6854

Timestamp:

03/18/05 14:59:57 (20 years ago)

Author:

hbartko

Message:

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File:

• trunk/MagicSoft/GC-Proposal/GC.tex (modified) (3 diffs)

trunk/MagicSoft/GC-Proposal/GC.tex

@@ -268 +268 @@
 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,Bergstrom2004}.
 
-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 $E_{\mathrm{th}}$ per solid angle $\Omega$ 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 $E_{\mathrm{th}}$ per solid angle $\Omega$ is given by:
 
 \begin{equation*}
@@ -275 +277 @@
 
 
-where $\langle \sigma v \rangle$ is the thermally averaged annihilation cross section, $m_{\chi}$ the mass and $\rho_{\chi}$ the spatial density distribution of the hypothetical dark matter particles. $N_{\gamma}(E_{\gamma}>E_{\mathrm{th}})$ is the gamma yield above the threshold energy per annihilation. The predicted flux depends on the SUSY parameters and on the spatial distribution of the dark matter. The energy spectrum 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.
+where $\langle \sigma v \rangle$ is the thermally averaged annihilation cross section, $m_{\chi}$ the mass and $\rho_{\chi}$ the spatial density distribution of the hypothetical dark matter particles. $N_{\gamma}(E_{\gamma}>E_{\mathrm{th}})$ is the gamma yield above the threshold energy per annihilation. The predicted flux depends on the dark matter particle properties and on the spatial distribution of the dark matter. The energy spectrum 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 a density enhancement in the center of the dark halo. In the very center the dark matter density can be even more enhanced through an adiabatic compression due to the baryons \cite{Prada2004} present. Depending on the steepness of the density profile and on the instrument PSF some source extension might be observed. Nevertheless, the profiles which yield the largest flux \cite{Moore1998,Prada2004} predict nearly point-like sources.
@@ -282 +284 @@
 % 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 profile $\rho_{\chi}$ of the dark matter can be made \cite{Fornego2004,Evans2004}. On the other hand, for a given choice of SUSY parameters $m_{\chi},\;\langle \sigma v \rangle$ and $N_{\gamma}$ are determined. 
+Using fits of these dark matter profiles to the rotation data of the Milky Way predictions for the density profile $\rho_{\chi}$ of the dark matter can be made \cite{Fornego2004,Evans2004}. On the other hand, for a given model of the dark matter particles $m_{\chi},\;\langle \sigma v \rangle$ and $N_{\gamma}$ are determined. Combining the SUSY predictions with the predictions for the DM density profile
+predictions for the gamma flux from SUSY particle dark matter annihilation are derived.
 %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 
-Combining the SUSY predictions with the predictions for the DM density profile
-predictions for the gamma flux from SUSY particle dark matter annihilation are derived.
-
 
 Figure \ref{fig:exclusion_lmits} shows exclusion limits for MAGIC (solid straight lines) for the four most promising sources,