Index: /trunk/MagicSoft/GC-Proposal/GC.tex =================================================================== --- /trunk/MagicSoft/GC-Proposal/GC.tex (revision 6783) +++ /trunk/MagicSoft/GC-Proposal/GC.tex (revision 6784) @@ -278,5 +278,5 @@ Figure \ref{fig:exclusion_lmits} shows exclusion limits for MAGIC (solid straight lines) for the four most promising sources, -in the plane $N_{\gamma}(E_{\gamma}>E_{\mathrm{thresh}})\langle \sigma v \rangle$ vs. $m_{\chi}$. Due to its proximity the GC yields the largest expected flux from particle dark matter annihilation. Nevertheless, this minimum measurable flux is more than one order of magnitude above the highest fluxes predicted by SUSY models. Also the flux measured by the HESS experiment is far above the theoretical expectation. +in the plane $N_{\gamma}(E_{\gamma}>E_{\mathrm{thresh}})\langle \sigma v \rangle$ vs. $m_{\chi}$. The energy threshold $E_th$ has been assumed to be 100 GeV. Due to its proximity the GC yields the largest expected flux from particle dark matter annihilation and thus the lowest exclusion limit. Nevertheless, this minimum measurable flux is more than one order of magnitude above the highest fluxes predicted by SUSY models (full circles). Also the flux measured by the HESS experiment is far above the theoretical expectation. @@ -285,5 +285,5 @@ \includegraphics[totalheight=6cm]{plot_DM_exclusion.eps}%{Dark_exclusion_limits.eps} \end{center} -\caption[DM exclusion limits.]{Exclusion limits (solid straight lines) for the four most promising sources of dark matter annihilation radiation. The GC is expected to give the largest flux from all sources. For energies above 700 GeV, the flux from the GC as observed by the HESS experiment (dotted line)is within the reach of MAGIC. The solid points represent flux predictions from some typical SUSY models. -- Figure to be updated --} \label{fig:exclusion_lmits} +\caption[DM exclusion limits.]{Exclusion limits (solid straight lines) for the four most promising sources of dark matter annihilation radiation. The GC is expected to give the largest flux from all sources. For energies above 700 GeV, the flux from the GC as observed by the HESS experiment (dotted line) is within the reach of MAGIC. The full circles represent flux predictions from some typical SUSY models. -- Figure to be updated --} \label{fig:exclusion_lmits} \end{figure} @@ -300,6 +300,5 @@ still being analyzed. Preliminary results were presented at the MAGIC collaboration meeting in Berlin, 21-25th February 2005.\\ -Up to now there is only 2.9 hours of ON data available at a very large zenith -angle range. Some details of the data set are shown in Table \ref{table:GC_dataset}.\\ +Up to now only 2.9 hours of ON data are available, at zenith angles between 60.3 and 67.8 degrees. Some details of the data set are shown in Table \ref{table:GC_dataset}.\\ \begin{table}[!ht]{ @@ -321,10 +320,9 @@ ZA (65$^\circ$ ZA and 205$^\circ$ Az) Monte Carlo gammas were generated, 99500 events in all, with energies between 200 -and 30,000 GeV. The slope of the generated spectrum is $-2.6$, conforming the -energy spectrum of the Crab nebula... - -The MC sample is divided into training -and test sample. Since there is no dedicated OFF data available, we used a -subsample of Sgr A$^*$ ON data for the Random Forest training. As training +and 30,000 GeV. The differential spectral index of the generated spectrum is $-2.6$, conforming with the energy spectrum of the Crab nebula. + +The MC sample was divided into a training +and a test sample. Since no dedicated OFF data were available, we used a +subsample of Sgr A$^*$ ON data to represent the hadronic background in the Random Forest training. As training parameters we used SIZE, DIST, WIDTH, LENGTH, CONC, and M3Long... @@ -348,5 +346,5 @@ -The observed differential gamma flux by the HESS collaboration is given by \cite{GC_hess}: +The differential gamma flux observed by the HESS collaboration is given by \cite{GC_hess}: \begin{equation} @@ -375,5 +373,5 @@ -Thus the expected integral fluxes above 700 GeV based on the HESS and Cangaroo data agree within errors. +Thus the integral fluxes above 700 GeV based on the HESS and Cangaroo data agree within errors. Using MC simulations \cite{MC-Camera} for small zenith angles we conservatively estimate MAGICs sensitivity \cite{MC-Sensitivity} to the integral flux to be: @@ -383,9 +381,10 @@ \end{equation} -Assuming this sensitivity MAGIC shall be able to get an excess at the 5 -$\sigma$ significance level in $1.8 \pm 0.5$ h observation time for both the -Cangaroo and HESS spectrum. The observed Cangaroo and HESS spectra differ +Assuming this sensitivity and using the integrated flux of $3.2\cdot 10^{-12} cm^{-2}s^{-1}$ MAGIC will obtain an excess at the 5 +$\sigma$ significance level in $1.8 \pm 0.5$ h observation time. + +The observed Cangaroo and HESS spectra differ substantially in the spectral index. While the Cangaroo spectrum only extends -to about 2 TeV, the recently published HESS spectrum goes up to about 9 TeV. Figure \ref{fig:MAGIC_flux_limits} shows the HESS and Cangaroo observed fluxes together with the mimimum detectable flux with MAGIC in 20 hours observation time. +to about 2 TeV, the recently published HESS spectrum goes up to about 9 TeV. Figure \ref{fig:MAGIC_flux_limits} shows the HESS and Cangaroo observed fluxes together with the mimimum flux detectable by MAGIC in 20 hours observation time. MAGIC will be able to solve the obvious discrepancy between the observed fluxes. Due to the observation under high zenith angle of about 60 deg MAGIC will be able to extend the source spectrum to higher energies. @@ -396,5 +395,5 @@ \includegraphics[totalheight=8cm]{MAGIC_flux_limits.eps} \end{center} -\caption[Flux limits.]{Observed gamma spectra of the HESS and Cangaroo experiments compared to the minimum detectable flux with the MAGIC telescope in 20 hours observation time.} \label{fig:MAGIC_flux_limits} +\caption[Flux limits.]{Observed gamma spectra of the HESS and Cangaroo experiments compared to the minimum flux detectable by the MAGIC telescope in 20 hours observation time.} \label{fig:MAGIC_flux_limits} \end{figure} @@ -423,5 +422,5 @@ Based on the above estimations a 5 $\sigma$ excess is expected to be observed in about 2 hours assuming the HESS flux. To acquire a comparable data set to the other experiments at least 20 hours of good ON data and 20 hours of good dedicated OFF data are needed. -To get the lowest possible threshold all data shall be taken under the +To get the lowest possible threshold all data shall be taken at the smallest possible zenith angles between culmination at about 58 deg and 60 deg. This limits the data taking interval to about 1 hour per night between @@ -435,5 +434,5 @@ In order to take part in exploring the exciting physics of the GC -we propose to start taking data as soon as possible beginning in April. In this way first results may be presented in the summer conferences 2005. +we propose to start taking data as soon as possible, beginning in April. In this way first results may be presented at the summer conferences 2005.