Changeset 6118 for trunk/MagicSoft/GRB-Proposal
- Timestamp:
- 01/29/05 17:26:54 (20 years ago)
- File:
-
- 1 edited
Legend:
- Unmodified
- Added
- Removed
-
trunk/MagicSoft/GRB-Proposal/Monitor.tex
r6102 r6118 11 11 in their wide FOV and send immediately the coordinates of the GRBs to the GCN network. 12 12 The network send the alerts to registered users and allows other satellites as well as 13 ground based observatories to observe the GRBs and their afterglows at different waveleng hts.14 The Burst Alarm System is composed by a mainprogram -15 the core of the system -which acts in two ways: on the13 ground based observatories to observe the GRBs and their afterglows at different wavelengths. 14 The Burst Alarm System is composed by a core program - 15 which acts in two ways: on the 16 16 one hand it manages the monitoring of the GCN, on the other it manages 17 17 the communication with the Central Control (CC). Then it also manages 18 18 three communication channels to notice the shifters 19 about a alert situation. The program is called {\it gspot} (Gamma19 about an alert situation. The program is called {\it gspot} (Gamma 20 20 Sources POinting Trigger). It is a C based daemon running 24 21 hours a day on tothe {\it www} machine, our external server, in a22 {\it stand alone} mode. It do not need to be operated and is23 fully automatic ally able to managenetwork diconnections21 hours a day on the {\it www} machine, our external server, in a 22 {\it stand alone} mode. It does not need to be operated and is 23 fully automatic. It manages network diconnections 24 24 within the external net and/or the internal one. 25 25 … … 27 27 \subsection{The connection to GCN} 28 28 29 The connection to GCNis performed by {\it gspot} through a30 TCP/IP connection within a computer at Goddard Space Flight31 Center (GSFC). This computer distributes the informations it is recievingfrom the satellite32 experiments through the normal internet socket connection. The {\it gspot} on toour29 The connection to {\it GRB Coordinates Network} (GCN)~\cite{GCN} is performed by {\it gspot} through a 30 TCP/IP connection to a computer at the Goddard Space Flight Center (GSFC). 31 This computer distributes the information it recieves from the satellite 32 experiments through the normal internet socket connection. The {\it gspot} on our 33 33 side acts as a server while the client, running at the GSFC, 34 34 manages the communication of the data concerning the GRBs 35 35 and concerning the status of the connnection. \\ 36 36 37 The format of the data distributed through GCN differ between the individual satellites37 The format of the data distributed through the GCN differ between the individual satellites 38 38 and the kind of package. There are three satellites participating in the GRB survey: 39 39 HETE-2, INTEGRAL and SWIFT. All are sending alerts which include the 40 40 UTC, coordinates (not always), error on coordinates 41 41 (not always) and intensity (photon counts) of the burst. 42 The first notice from HETE-2 and INTEGRAL usually do not include the coordinates.43 In only few cases coordinates are distibuted delayed in more refined notices.\\42 The first notices from HETE-2 and INTEGRAL usually do not include the coordinates. 43 In few cases only coordinates are distributed in more refined notices.\\ 44 44 45 In case of an alert {\it gspot} stores the informations and enters into46 an {\bf Alarm State}. The duration of the al ertstate depends on the following parameters:45 In case of an alert {\it gspot} stores the informations and enters 46 an {\bf Alarm State}. The duration of the alarm state depends on the following parameters: 47 47 48 48 \begin{itemize} … … 50 50 to the astronomical horizon of 108$^\circ$ zenith; 51 51 \item {\bf position of GRB}, the GRB equatorial 52 coordinates are transformed into local horizontal coordinates and comparised whether the53 GRB zenith angle is smaller than 70$^\circ$; in the case thatmoon is54 shining in the sky, we propose to reduce this zenith limith to 60$^\circ$;55 \item {\bf position of moon} , checking whether the angular56 distance from the GRB to the moon isat least 30$^\circ$.52 coordinates are transformed into local horizontal coordinates. 53 The resulting GRB zenith angle has to be smaller than 70$^\circ$; in the case that the moon is 54 shining, this zenith angle limit is reduced to 65$^\circ$; 55 \item {\bf position of moon} The angular 56 distance from the GRB to the moon has to be at least 30$^\circ$. 57 57 \end{itemize} 58 58 59 If one or more of these conditions fail ed then{\it gspot}59 If one or more of these conditions fail, {\it gspot} 60 60 enters into a {\bf Yellow Alarm State}. It means that the GRB is not observable 61 at the moment. Currently the program do not calculate if and when the GRB will61 at the moment. Currently the program does not calculate if and when the GRB will 62 62 become observable at La Palma. 63 63 If all conditions mentioned above are satisfied, … … 65 65 the GRB is considered to be observable at the current time.\\ 66 66 67 In both cases (in RED and YELLOW alarm state) {\it gspot} assamblethe communication68 with the C Cand sends the GRB equatorial coordinates (RA/DEC J2000).69 For the communication to CC the format defined in 67 In both cases (in RED and YELLOW alarm state) {\it gspot} establishes the communication 68 with the Central Control and sends the GRB equatorial coordinates (RA/DEC J2000). 69 For the communication to CC the format defined in~\cite{CONTROL} is used. In the same time 70 70 the shifters and the GRB-MAGIC group is contacted in different ways described in the next sessions. 71 71 72 72 \subsection{The interface to the Central Control} 73 73 74 An interface of {\it gspot} sends all the relevant informations about it's statusto {\it arehucas}.74 An interface to {\it gspot} sends all the relevant information to {\it arehucas}. 75 75 In the case of {\bf NO Alarm State} the standard packages, containing the main global status 76 76 of the two subsystems, are continuosly excanged between CC and {\it gspot}. 77 77 In the alert case {\it gspot} starts to send to CC special alert packages, 78 containg major informations of the GRB and onthe ''colour'' of the alert.78 containg information about of the GRB and the ''colour'' of the alert. 79 79 The exchange of the alert packages continues untill the following steps occur: 80 80 81 81 \begin{itemize} 82 \item {\it gspot} getfrom {\it arehucas} the confirmation83 that it recived the alert notice; {\it arehucas} must send the alert back in order to82 \item {\it gspot} receives from {\it arehucas} the confirmation 83 that it has received the alert notice; {\it arehucas} must send the alert back in order 84 84 to perform a crosscheck of the relevant data; 85 85 \item the alarm state expire after {\bf 5 hours}.
Note:
See TracChangeset
for help on using the changeset viewer.