Changeset 6852


Ignore:
Timestamp:
03/18/05 13:56:50 (20 years ago)
Author:
commichau
Message:
*** empty log message ***
Location:
trunk/MagicSoft/GC-Proposal
Files:
2 added
2 edited

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  • trunk/MagicSoft/GC-Proposal/Changelog

    r6835 r6852  
     12005/03/18 Sebastian
     2* GC.tex
     3  Did some small corrections. Results of the preliminary analysis changed
     4  and added two ALPHA plots for two different lower cuts in SIZE.
     5* added and committed the files
     6  alpha_tmpl_s100_h006.eps and alpha_tmpl_s800_h02.eps
     7  to the repository
     8
    192005/03/16 Hendrik
    210* GC.tex:

  • trunk/MagicSoft/GC-Proposal/GC.tex

    r6851 r6852  
    6262At La Palma, the GC culminates at about 58 deg zenith angle (ZA). It can be
    6363observed with MAGIC at up to 60 deg ZA, between
    64 April and late August, yielding a total of 150 hours per year. The expected integral flux above 700 GeV derived from
     64April and late August, yielding a total of 150 hours without moon per year.
     65The expected integral flux above 700 GeV derived from
    6566the HESS data is $(3.2 \pm 1.0)\cdot 10^{-12}\mathrm{cm}^{-2}\mathrm{s}^{-1}$.
    6667Comparing this to the expected MAGIC sensitivity from MC simulations, this
    … …  
    6970The observations have to be conducted as early as possible in order to
    7071participate in the ongoing discussion about gamma radiation from the GC.
    71 The main motivations for the observation of the GC are :
     72The main motivations for the observation of the GC are:
    7273
    7374\begin{itemize}
    … …  
    8485In order to collect a data sample comparable in size to those of the other
    8586experiments and to be able to measure the energy spectrum, 40 hours of
    86 observation time are requested. The 40 hours will be split into 20 hours ON
     87observation time are requested. This 40 hours will be split into 20 hours ON
    8788and 20 hours dedicated OFF data or they will be devoted to observations in
    8889the wobble mode. In addition, 60 hours of observation during moonshine are
    … …  
    166167\end{figure}
    167168
    168 The discrepancies between the measured flux spectra could indicate inter-calibration problems between the IACTs. It could indicate an apparent source variability of the order of one year or it could be due to the different regions in which the signal is integrated.
     169The discrepancies between the measured flux spectra could indicate
     170inter-calibration problems between the IACTs. But it could also indicate an
     171apparent source variability at a timescale of about of one year or it could be due to the different regions in which the signal is integrated.
    169172
    170173
    … …  
    185188 Investigator & Institution& E-mail & Assigned task\\ \hline
    186189   Hendrik Bartko      & MPI Munich    & hbartko@mppmu.mpg.de & data analysis, spectra, wobble mode
    187 \\ Adrian Biland       & ETH Zurich    & biland@particle.phys.ethz.ch & OFF pointing, Moon observations
    188 \\ Erica Bisesi        & Univ. Udine   & bisesi@fisica.uniud.it & dark matter halo modelling, clumpness
     190\\ Adrian Biland       & ETH Zurich    & biland@particle.phys.ethz.ch & MC generation, Moon observations
     191\\ Erica Bisesi        & Univ. Udine   & bisesi@fisica.uniud.it & dark matter halo modelling, clumpness
    189192\\ Sebastian Commichau & ETH Zurich    & commichau@particle.phys.ethz.ch &
    190  data analysis, MC generation, spectra
     193 data analysis, spectra, geomagnetic effects
    191194\\ Pepe Flix           & IFAE Barcelona& jflix@ifae.es & data analysis, disp, spectra, dark matter
    192195\\ Sabrina Stark       & ETH Zurich    & lstark@particle.phys.ethz.ch  & data analysis, spectra
    … …  
    227230\begin{itemize}
    228231\item{source location, source extension}
    229 \item{time variability of the gamma flux}
    230 \item{energy spectrum.}
     232\item{energy spectrum}
     233\item{time variability of the gamma flux.}
    231234\end{itemize}
    232235
    … …  
    258261\subsubsection{Hadronic Models}
    259262
    260 One scenario is related to protons accelerated to about $10^{18}$ eV \cite{Aharonian2005}. These protons produce gamma rays via photo-meson processes. This scenario also predicts detectable fluxes of  $10^{18}$ eV neutrons and perhaps gamma rays and neutrinos. A hint of an excess of highest energy neutrons from the GC has been reported in \cite{Hayashida1999}.
     263Another scenario is related to protons accelerated to about $10^{18}$ eV \cite{Aharonian2005}. These protons produce gamma rays via photo-meson processes. This scenario also predicts detectable fluxes of  $10^{18}$ eV neutrons and perhaps gamma rays and neutrinos. A hint of an excess of highest energy neutrons from the GC has been reported in \cite{Hayashida1999}.
    261264
    262265TeV gamma rays can also be produced by significantly  lower energy protons, accelerated by the electric filed close to the gravitational radius of the black hole or by strong shocks in the accretion disk \cite{Aharonian2005}. In this case the gamma-ray production is dominated by interactions of $10^{13}$ eV protons with the accretion plasma. This scenario predicts a neutrino flux which should be observable with northern neutrino telescopes like NEMO and Antares. It also predicts strong TeV--X-ray--IR correlations.
    … …  
    318321 \hline
    319322   Date       & Time          & Az $[^\circ]$ & ZA $[^\circ]$\\ \hline
    320    09/08/2004 & 21:00 - 22:00 & 198.3 - 214.7 & 60.3 - 67.8
    321 \\ 09/09/2004 & 21:17 - 22:12 & 203.4 - 214.7 & 62.2 - 67.7
     323   09/08/2004 & 21:00 - 22:16 & 198.3 - 214.7 & 60.3 - 67.8
     324\\ 09/09/2004 & 21:17 - 22:12 & 203.4 - 214.7 & 62.0 - 67.7
    322325\\ 09/10/2004 & 21:06 - 22:03 & 202.2 - 213.7 & 61.6 - 67.1
    323326\\
    … …  
    334337
    335338The MC sample was divided into a training
    336 and a test sample. Since no dedicated OFF data were available, we used a
     339and a test sample and its slope was normalized to $-2.21$. Since no dedicated OFF data were available, we used a
    337340subsample of Sgr A$^*$ ON data to represent the hadronic background in the Random Forest training. As training
    338 parameters we used SIZE, DIST, WIDTH, LENGTH, CONC, and M3Long...
    339 
    340 
    341 %\begin{figure}[!h]
    342 %\centering
    343 %\subfigure[The Hadronness distribution.]{
    344 %\includegraphics[scale= .3]{hadronness}}
    345 %\subfigure[SIZE $> 300$ Phe]{
    346 %\includegraphics[scale= .3]{size300}}
    347 %\subfigure[SIZE $> 500$ Phe]{
    348 %\includegraphics[scale= .3]{size500}}
    349 %\subfigure[SIZE $> 1000$ Phe]{
    350 %\includegraphics[scale= .3]{size1000}}
    351 %\caption{Hadronness distribution and ALPHA plots for three different lower SIZE cuts. The
    352 %  Hadronness cut is made at 0.4.}\label{fig:prelresults}
    353 %\end{figure}
    354 
    355 The results of the preliminary analysis can be summarized as follows. After the gamma/hadron separation, the ALPHA distributions of the ON data show excess signals of 121 and 32 events, with significances of 5.2 and 3.7 $\sigma$, for SIZE values above 300 p.e. and 800 p.e., respectively. If the SIZE cut at 300 p.e. corresponds to an energy threshold of 1.9 TeV and if the effective collection area is assumed to be 1.e5 m$^2$ the observed excess is by a factor of 10 higher than that expected on the basis of the HESS flux.
    356 
    357 Studies are going on concerning appropriate OFF data, the false-source plot and better estimates of the energy threshold and the effective collection area.
     341parameters we used SIZE, DIST, WIDTH, LENGTH, CONC, and M3Long. The training
     342was done for SIZE $>100$ p.e..
     343
     344\begin{figure}[!h]
     345\centering
     346\subfigure[SIZE $> 300$ p.e.]{
     347\includegraphics[scale= .3]{alpha_tmpl_s100_h006}}
     348\subfigure[SIZE $> 500$ p.e.]{
     349\includegraphics[scale= .3]{alpha_tmpl_s800_h02}}
     350\caption{Preliminary ALPHA distributions for lower SIZE cuts of 100 and 800 p.e..}\label{fig:prelresults}
     351\end{figure}
     352
     353The results of the preliminary analysis can be summarized as follows. After
     354the gamma/hadron separation, the ALPHA distributions of the ON data show
     355excess signals of 60 and 12 events, with significances of 3.5 and 2.5
     356$\sigma$, for SIZE values above 100 p.e. and 800 p.e., respectively (figure \ref{fig:prelresults}). If the
     357SIZE cut at 100 p.e. corresponds to an energy threshold of 900 GeV and if the
     358effective collection area is assumed to be $10^5$ m$^2$ the observed excess is
     359by a factor of 5 higher than that expected on the basis of the HESS flux.
     360
     361Studies are going on concerning appropriate OFF data, the false-source plot
     362and better estimates of the energy threshold and the effective collection area.
    358363
    359364
    … …  
    392397                              & $T_{5\sigma}$       \\
    393398             &                & above $E_{\mathrm{th}}$ &   &\\
    394 $[^{\circ}]$ & $[{\rm GeV}]$  & $[{\rm cm}^2\;{\rm s}]^{-1}$ 
    395                               & $[{\rm cm}^2\;{\rm s}]^{-1}$     
     399$[^{\circ}]$ & $[{\rm GeV}]$  & $[{\rm cm}^{-2}\;{\rm s}^{-1}]$ 
     400                              & $[{\rm cm}^{-2}\;{\rm s}^{-1}]$     
    396401                              &  $ [{\rm hours}]$   \\
    397402\hline
    … …  
    400405\hline
    401406\end{tabular}
    402 \caption{Energy threshold $E_{\mathrm{th}}$ and sensitivity for MAGIC for 2 zenith angles ZA. The 4th and 5th column contain the expected integrated flux above $E_{\mathrm{th}}$ and the time needed for observing a 5$\sigma$ excess, respectively.}\label{table:MAGIC_sensitivity}}
     407\caption{Energy threshold $E_{\mathrm{th}}$ and sensitivity for MAGIC for two zenith angles ZA. The 4th and 5th column contain the expected integrated flux above $E_{\mathrm{th}}$ and the time needed for observing a 5$\sigma$ excess, respectively.}\label{table:MAGIC_sensitivity}}
    403408\end{table}
    404409
    … …  
    476481\includegraphics[totalheight=16cm]{GCregion14.eps}
    477482\end{center}
    478 \caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The 2 big circles correspond to distances of 1$^{\circ}$ and 1.75$^{\circ}$ from the GC, respectively. The x axis is pointing into the direction of decreasing RA, the y axis into the direction of increasing declination. The grid spacing in the declination is 20 arc minutes. The Galactic Plane is given by the dotted line.
     483\caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The 2 big circles correspond to distances of 1$^{\circ}$ and 1.75$^{\circ}$ from the GC, respectively. The $x$ axis is pointing into the direction of decreasing RA, the $y$ axis into the direction of increasing declination. The grid spacing in the declination is 20 arc minutes. The Galactic Plane is given by the dotted line.
    479484} \label{fig:GC_starfield}
    480485\end{figure}
    … …  
    484489\includegraphics[totalheight=16cm]{GCregion14largeW.eps}
    485490\end{center}
    486 \caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The 2 big circles correspond to distances of 1$^{\circ}$ and 1.75$^{\circ}$ from the GC, respectively. The wobble positions WGC1 and WGC2 are given by the full circles. The x axis is pointing into the direction of decreasing RA, the y axis into the direction of increasing declination. The grid spacing in the declination is 1 degree.
     491\caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The 2 big circles correspond to distances of 1$^{\circ}$ and 1.75$^{\circ}$ from the GC, respectively. The wobble positions WGC1 and WGC2 are given by the full circles. The $x$ axis is pointing into the direction of decreasing RA, the $y$ axis into the direction of increasing declination. The grid spacing in the declination is 1 degree.
    487492} \label{fig:GC_starfield_largeW}
    488493\end{figure}
    … …  
    492497\includegraphics[totalheight=16cm]{GCregionOFF1.eps}
    493498\end{center}
    494 \caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The ON region is indicated by the bigger circle in the center. A possible OFF region is shown by the bigger circle in the left upper part of the figure. The x axis is pointing into the direction of decreasing RA, the y axis into the direction of increasing declination. The grid spacing in the declination is 1 degree.
     499\caption[Star field around the GC.]{Star field around the GC. Stars up to a magnitude of 14 are plotted. The ON region is indicated by the bigger circle in the center. A possible OFF region is shown by the bigger circle in the left upper part of the figure. The $x$ axis is pointing into the direction of decreasing RA, the $y$ axis into the direction of increasing declination. The grid spacing in the declination is 1 degree.
    495500} \label{fig:GC_starfield_OFF1}
    496501\end{figure}
    … …  
    518523
    519524
    520 To increase statistics we propose to take data during moonshine in addition. Also in this case, the maximum ZA of 60 deg should not be exceeded.
     525To increase statistics at high energies we propose to take additional data during moonshine. Also in this case, the maximum ZA of 60 deg should not be exceeded.
    521526
    522527In order to take part in exploring the exciting physics of the GC
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