Changeset 6835


Ignore:
Timestamp:
03/16/05 15:20:50 (20 years ago)
Author:
hbartko
Message:
*** empty log message ***
Location:
trunk/MagicSoft/GC-Proposal
Files:
3 edited

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  • trunk/MagicSoft/GC-Proposal/Changelog

    r6801 r6835  
     12005/03/16 Hendrik
     2* GC.tex:
     3  added E. Bisesi as author
     4  some text modifications
     5* bibbib.bib
     6  new referece for Random Forrest
     7
     82005/03/15 Wolfgang
     9* GC.tex:
     10  new text for Observation Mode
    111
    2122005/03/09 Sebastian
  • trunk/MagicSoft/GC-Proposal/GC.tex

    r6834 r6835  
    274274
    275275
    276 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.
    277 
    278 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 halos. In the very center the dark matter density can be 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.
     276where $\langle \sigma v \rangle$ 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.
     277
     278Numerical 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. All dark matter distributions that predict observable fluxes are cusped, yielding an approximately point-like source.
    279279
    280280Using 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.
     
    323323\end{table}
    324324
    325 In our preliminary analysis we used the Random Forest method for the gamma
     325In our preliminary analysis we used the Random Forest method \cite{RF} for the gamma
    326326hadron separation. For this purpose high
    327 ZA (65$^\circ$ ZA and 205$^\circ$ Az) Monte Carlo gammas were generated,
     327ZA (65$^\circ$ ZA and 205$^\circ$ Az) Monte Carlo gammas showers were generated,
    32832899500 events in all, with energies between 200
    329329and 30,000 GeV. The differential spectral index of the generated spectrum is $-2.6$, conforming with the energy spectrum of the Crab nebula.
     
    400400
    401401
    402 Figure \ref{fig:MAGIC_flux_limits} shows the HESS and Cangaroo fluxes together with the minimum flux detectable by MAGIC in 20 hours observation time.
     402Figure \ref{fig:MAGIC_flux_limits} shows the measured HESS and Cangaroo fluxes together with the minimum flux detectable by MAGIC in 20 hours observation time.
    403403
    404404
     
    429429
    430430
    431 The GC culminates at about 58 deg ZA in La Palma. Below 60 deg ZA, it is visible between April and late August for about 150 hours. The GC region has a quite high level of background light from the night sky. This together with the large ZA requires to take either dedicated OFF data or to take data in the wobble mode (see Section \ref{section:skydirections}).
     431The GC culminates at about 58 deg ZA in La Palma. Below 60 deg ZA, it is visible between April and late August for about 150 hours. The GC region has a quite high and non-uniform level of background light from the night sky. This together with the large ZA requires to take either dedicated OFF data or to take data in the wobble mode (see Section \ref{section:skydirections}).
    432432%Since the LONS level is in any case very large moon observations are considered in addition to the normal observations.
    433 
    434 
    435 \section{Requested Observation Time}
    436 
    437 Based on the above estimates a 5$\sigma$ excess is expected to be observed in about 2 hours, under optimal conditions. To acquire a data set which is comparable in size to those of the other experiments at least 40 hours of observation time are requested. These 40 hours may be either split into 20 hours ON and 20 hours OFF data taking or be devoted exclusively to data taking in the wobble mode. At present, the prefered mode is the wobble mode. However, a final decision has not yet been taken.
    438 
    439 As pointed out in Section \ref{section:feasibility}, all data should be taken at the
    440 smallest possible zenith angles between culmination at about 58 deg and 60
    441 deg. This limits the data taking interval to about 1 hour per night between
    442 April and August.
    443 
    444 
    445 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.
    446 
    447 In order to take part in exploring the exciting physics of the GC
    448 we propose to start taking data as soon as possible, beginning in April. In this way first results may be available at the time of the summer conferences 2005.
    449433
    450434
     
    518502
    519503
     504\section{Requested Observation Time}
     505
     506Based on the above estimates, a 5$\sigma$ excess is expected to be observed in about 2 hours, under optimal conditions. To acquire a data set which is comparable in size to those of the other experiments at least 40 hours of observation time are requested. These 40 hours may be either split into 20 hours ON and 20 hours OFF data taking or be devoted exclusively to data taking in the wobble mode. At present, the prefered mode is the wobble mode. However, a final decision has not yet been taken.
     507
     508As pointed out in Section \ref{section:feasibility}, all data should be taken at the
     509smallest possible zenith angles between culmination at about 58 deg and 60
     510deg. This limits the data taking interval to about 1 hour per night between
     511April and August.
     512
     513
     514To 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.
     515
     516In order to take part in exploring the exciting physics of the GC
     517we propose to start taking data as soon as possible, beginning in April. In this way first results may be available at the time of the summer conferences 2005.
     518
     519
    520520
    521521\section{Outlook and Conclusions}
     
    540540The authors thank A. Moralejo for helpful discussions about the Monte Carlo simulations.
    541541
    542 \newpage
     542%\newpage
    543543
    544544\bibliography{bibbib}
  • trunk/MagicSoft/GC-Proposal/bibbib.bib

    r6827 r6835  
     1@Article{RF,
     2     author    = "Bock, R. K. and others",
     3     title     = "Methods for multidimensional event classification: A case
     4                  study using images from a Cherenkov gamma-ray telescope",
     5     journal   = "Nucl. Instrum. Meth.",
     6     volume    = "A516",
     7     year      = "2004",
     8     pages     = "511-528",
     9     SLACcitation  = "%%CITATION = NUIMA,A516,511;%%"
     10}
     11
    112@Article{Hooper2002,
    213     author    = "Hooper, Dan and Dingus, Brenda",
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