Changeset 6248 for trunk/MagicSoft/GRB-Proposal
- Timestamp:
- 02/03/05 19:17:29 (20 years ago)
- File:
-
- 1 edited
Legend:
- Unmodified
- Added
- Removed
-
trunk/MagicSoft/GRB-Proposal/Monitor.tex
r6235 r6248 21 21 22 22 23 \subsection{The connection to the GCN}23 \subsection{The Connection to the GCN} 24 24 25 25 The connection to the \g is performed by {\it gspot} through a … … 43 43 44 44 In case of an alert {\it gspot} stores the informations and enters 45 an {\bf Alarm State}. The duration of the alarm statedepends on the following parameters:45 an {\bf Alarm State}. The duration of the alarm depends on the following parameters: 46 46 47 47 \begin{itemize} 48 \item {\bf Darkness of the sky}: Determined from the distance of the sun49 to the astronomical horizon of 108$^\circ$ zenith;48 \item {\bf Darkness of the sky}: The Sun has to be below 49 to the astronomical horizon at 108$^\circ$ zenith. 50 50 \item {\bf Position of GRB}: The GRB equatorial 51 51 coordinates are transformed into local horizontal coordinates. 52 52 The resulting GRB zenith angle has to be smaller than 70$^\circ$. In case that the moon is 53 shining, the zenith angle limit is reduced to 65$^\circ$ ;53 shining, the zenith angle limit is reduced to 65$^\circ$. 54 54 \item {\bf Position of moon}: The angular 55 55 distance from the GRB to the moon has to be at least 30$^\circ$. 56 56 \end{itemize} 57 57 58 If one or more of these conditions fail, {\it gspot} enters into a \text 59 {yellow}{\bf Yellow Alarm State}. It means that the GRB is not observable at the moment. 60 Currently the program does not calculate if and when the GRB will become observable for \ma. 61 If all conditions mentioned above are satisfied, {\it gspot} enters into a \textcolor{red}{\bf Red Alarm State}, it means that the GRB is considered to be observable now.\\ 62 63 In both cases (in \textcolor{red}{RED} and \textcolor{yellow}{YELLOW} alarm state) {\it gspot} establishes the communication with the CC and sends the GRB equatorial coordinates (RA/DEC J2000). 64 For the communication with CC the format defined in~\cite{CONTROL} is used. In the same time 65 the shifters and the GRB-MAGIC group is contacted in different ways as described in the next sessions. 66 67 \subsection{The interface to the Central Control} 68 69 An interface of {\it gspot} sends all the relevant information to {\it arehucas}. 70 In the case of {\bf NO Alarm State} the standard packages, containing the main global status 71 of the two subsystems, are continuously exchanged between CC and {\it gspot}. 72 In the alert case {\it gspot} starts to send to CC special alert packages, 73 containing information about of the GRB and the ''color'' of the alert. 74 The exchange of the alert packages continues until the following steps occur: 58 If one or more of these conditions fail, {\it gspot} enters into a 59 {\color[rgb]{0.9,0.75,0.}\bf Yellow Alarm State}: The GRB is not observable at the moment. 60 Currently, the program does not calculate if and when the GRB will become observable for \ma. 61 If all the mentioned conditions are satisfied, 62 {\it gspot} enters into a \textcolor{red}{\bf Red Alarm State}, it means that the GRB is considered to be observable now.\\ 63 64 In both cases (in \textcolor{red}{\bf RED} and {\color[rgb]{0.9,0.75,0.}\bf YELLOW} Alarm State), {\it gspot} establishes the communication with the CC and sends the GRB equatorial coordinates (RA/DEC J2000). 65 For the communication with CC the format defined in~\cite{CONTROL} is used. At the same time, 66 the shifters and the GRB-MAGIC group is contacted. 67 68 \subsection{The Interface to the Central Control} 69 70 An interface of {\it gspot} sends all the relevant information to the CC. 71 In the case that {\it gspot} is not in alarm state, 72 the standard packages are continuously exchanged between CC and {\it gspot}, containing the main global status 73 of the two subsystems. 74 In the alert case, {\it gspot} starts to send special alert packages to the CC, 75 containing information about the GRB and the ''color'' of the alert. 76 The exchange of the alert packages continues until: 75 77 76 78 \begin{itemize} 77 \item {\it gspot} receives from {\it arehucas}the confirmation78 that it has received the alert notice; {\it arehucas} must send the alert backin order79 to perform a cross-check of the relevant data 80 \item the alarm state expire after {\bf 5 hours}79 \item {\it gspot} receives from the CC the confirmation 80 that the alert notice has been received; The CC must send back the alert in order 81 to perform a cross-check of the relevant data. 82 \item the alarm state expires after {\bf 5 hours} 81 83 \end{itemize} 82 84 83 At the moment {\it arehucas} informs the shift crew about the alert and takes 84 further steps only in case of red alerts. In this case a pop-up window 85 The CC informs the shift crew about the alert and undertakes 86 further steps only in case of a \textcolor{red}{\bf red alerts}. 87 In this case, a pop-up window 85 88 appears with all the alert information received by the burst monitor. 86 89 The operator has to confirm the notice by closing the pop-up window. 87 90 He can decide to stop the current scheduled observation and to point the GRB. 88 A new button in the CC will be displayedand allows to point the telescope to89 the GRB coordinates by pushing it.90 91 \subsection{GRB archive and emails to the GRB-mailing list}91 A new button will be displayed in the CC and allows to point the telescope to 92 the GRB coordinates. 93 94 \subsection{GRB Archive and Emails to the GRB-mailing List} 92 95 93 96 In case of an alert -- even if it did not contain the necessary coordinates -- the 94 97 information is translated into ''human language'' and stored in ASCII files. 95 At the same time an e-mail is sent to the MAGIC GRB-mailing list. 96 97 \subsection{The GRB web page} 98 99 The status of the GRB Alert System and relevant informations about the lastest 100 alert are displayed on a separate web page. The page is hosted at the web server in La Palma. 101 The address is the following:\\ 98 At the same time, an e-mail is sent to the MAGIC GRB-mailing list 99 {\it GrB@magic.iac.es}. 100 101 \subsection{The GRB Web Page} 102 103 The status of the GRB Alert System and relevant informations about the latest 104 alert are displayed on a separate web page. The page is hosted at the web server in La Palma a 105 and can be accessed under:\\ 102 106 103 107 \qquad \qquad http://www.magic.iac.es/site/grbm/\\ … … 106 110 the status of the Burst Alarm System can be checked by the shifters and from outside. 107 111 108 \subsection{The acoustic alert}112 \subsection{The Acoustic Alert} 109 113 110 114 A further CC-independent acoustic alarm called {\it phava} 111 115 (PHonetic Alarm for Valued Alerts) will be installed 112 in La Palma verysoon. It will provide a loud acoustic signal113 even if {\it arehucas}is switched off, so that persons in the counting house114 willbe noticed about the alert situation. The signal will be on as long as115 {\it gspot} stays in alarm state, and in any casefor a minimum of 1 minute.116 Th is device featurealso a display with the status of the system and the alert.117 118 \subsection{Summary of alerts received until now}119 120 Since July , 15th 2004{\it gspot} has been working stably at La Palma.121 It received about 100 alerts from HETE-2 and INTEGRAL, out of which122 only 21 contained GRB's coordinates. Time delays 123 were in the order of several minutes to tens of minutes. The Burst Monitor can be considered bug-free since124 November 2004. From this moment we received the following two significant alerts:\\116 in La Palma soon. It will provide a loud acoustic signal 117 even if the CC is switched off, so that persons in the counting house 118 can be noticed about the alert situation. The signal will be on as long as 119 {\it gspot} remains in alarm state, and for a minimum of 1 minute. 120 The device features also a display with the status of the system and the alert. 121 122 \subsection{Summary of Alerts Received Until Now} 123 124 Since July 15$^{th}$, 2004, {\it gspot} has been working stably at La Palma. 125 It has received about 100 alerts from HETE-2 and INTEGRAL, out of which 126 21 contained GRB's coordinates. Time delays to the onset of the burst 127 were of the order of several minutes to tens of minutes. The Burst Monitor can be considered stable 128 since November, 2004. Since then, we have received the following two significant alerts:\\ 125 129 126 130 \begin{tabular}{lllcccl} … … 129 133 \end{tabular} 130 134 131 In both cases the weather conditions at La Palma were verybad.132 133 \subsection{Experience ofSWIFT GRBs until now}134 135 According to the \sw home page~\cite{SWIFT} the satellite detected 12 GRBs since midDecember last year.136 The bursts were detected by chance during the com issioning phase. The satellite did not send137 the coordinates on time to \g. Anyhow, in the current sample aretwo bursts138 which in principlecould have been observed by \ma:\\135 In both cases the weather conditions at La Palma were bad. 136 137 \subsection{Experience from SWIFT GRBs until now} 138 139 According to the \sw home page~\cite{SWIFT}, the satellite has detected 12 GRBs since mid-December last year. 140 The bursts were detected by chance during the commissioning phase. The satellite did not send 141 the coordinates to the \g on time. The current sample contains two bursts 142 which could have been observed by \ma:\\ 139 143 140 144 \begin{tabular}{lllcc} … … 143 147 \end{tabular} 144 148 145 \subsection{Comparison between the satellite orbits} 146 147 Figure~\ref{fig:orbit} show the difference between the orbits of the \sw, \he and \ig satellite. 148 The \sw and \he satellites are situated in a circular orbit with 20.6$^\circ$ respectivly 2$^\circ$ inclination. The revolution period of the \sw and \he satellite add up to 100min. The \ig satellite is situated in an highly eccentric orbit with a revolution period around the Earth of three sidereal days. 149 \subsection{Comparison between the Satellite Orbits} 150 151 Figure~\ref{fig:orbit} shows the orbits of the \sw, \he and \ig satellites. 152 The \sw and \he satellites are situated in a circular orbit with 153 20.6$^\circ$ and 2$^\circ$ inclination, respectively. 154 One revolution of the \sw and \he satellites last about 100\,min. 155 The \ig satellite has a 156 highly eccentric orbit with a revolution period of three sidereal days around the Earth. 149 157 150 158 \par 151 159 152 It is difficult to make strong conclusions from the individual satellite orbit. The orientation of the satellite FOV is influenced by the scheduled targets. Hovewer, \sw is the satellite with the largest inclination and overlaps mostly with the FOV of \ma. This increases the chance to recive {\bf Red Alarm} from this satellite. 160 It is difficult to draw strong conclusions from the individual satellites' orbits. 161 The orientation of the satellites' FOV is influenced by the scheduled targets. 162 However, \sw is the satellite with the largest inclination and overlaps mostly with the FOV of \ma. 163 This increases the chance to receive {\bf Red Alarms} from this satellite. 153 164 154 165 \begin{figure}[htp] 155 166 \centering 156 167 \includegraphics[width=0.7\linewidth]{GCNsatellites.eps} 157 \caption{Orbits of the \sw, \he and \ig satellites} 168 \caption{Orbits of the \sw (top), \he (center) and \ig (bottom) satellites: The pointed lines 169 show the orbit while the drawn lines show the horizon of the Sun. Here, a typical night at 170 La Palma is shown. The \sw satellite passes over the Roque seven times each night.} 158 171 \label{fig:orbit} 159 172 \end{figure} 160 173 161 \subsection{Routines to be defined}174 \subsection{Routines to Be Defined} 162 175 163 176 The Burst Alarm System is currently able to provide the minimum … … 168 181 \item {\bf Yellow Alarm strategy}: 169 182 The strategy to follow a {\bf Yellow Alarm} is not defined yet. 170 In such a case the CC does not undertake any steps, 171 except confirming the alarm notice to the Burst Monitor. We do not 172 calculate if and when the GRB will become observable. 173 It would make sense to check if during the period of 5 hours we could point to the burst. 174 Then, the Alarm System should change to the {\bf Red Alarm State} 175 at that time and allow the observation. 183 In such a case, the CC does not undertake any steps, 184 except confirming the alarm notice to the Burst Monitor. We have not 185 calculated yet if and when the GRB will become observable. 186 It would make sense to check if we could point to the burst during the period of 5 hours. 187 The Alarm System should change to a {\bf Red Alarm State}, then. 176 188 177 189 \item {\bf Sequence of alerts}: 178 190 How to deal with new alerts that are distributed during the time 179 that {\it gspot} is in alarm state? Currently {\it gspot}191 that {\it gspot} is in alarm state? Currently, {\it gspot} 180 192 locks its alert status until it exits the alarm state (see session 2.2). 181 This feature was implemented to avoid any loose of the GRB information. 182 Such a situation can occur when for example more than one burst alert is send before 183 the shift crew starts the CC. To solve the problem we will change the {\it gspot} routine by implementing a list of the available GRB alerts. 193 This feature was implemented to avoid any loss of GRB information. 194 Such a situation can occur for example if more than one burst alert is sent before 195 the shift crew launches the CC. 196 To solve this problem, we will change the {\it gspot} routine 197 by implementing a list of all available GRB alerts. 198 184 199 185 200 \par 186 201 187 202 If more than one alert is present in the list, the program 188 will weight the possible GRBs onthe following criteria:203 will weight the possible GRBs according to the following criteria: 189 204 (1) the total time of observability within the canonical 5 hours, 190 205 (2) the intensity of the burst and 191 206 (3) the time until the GRB becomes observable. 192 The information of the best GRB will be sen dto the CC.207 The information of the best GRB will be sent to the CC. 193 208 194 209 \end{itemize}
Note:
See TracChangeset
for help on using the changeset viewer.