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This page provides information about the Phase 2 preparation of
approved programs that require the use of the Rapid Response Mode (RRM), and
specifies the guidelines for activation.
The RRM at the VLT (and at the 2.2m-telescope for GROND) allows the automatic trigger of observations of
transient phenomena requiring almost immediate follow-up, such as gamma-ray bursts,
novae, or supernovae. It basically works as follows:
- An observation trigger signal is sent via an ASCII file to the ftp
server acweb.hq.eso.org (134.171.2.5), requesting the execution of a specific
Observation Block (OB).
- A program at the telescope is continuously monitoring the dedicated ftp
directory.
- When a valid trigger signal is found in the ftp directory the on-going
observation is ended, the telescope automatically presets to the coordinates
specified in the ftp file, and performs the requested observations as
specified in the trigger signal.
- Once a RRM proposal is approved, a complete Phase 2 package (Observation Blocks
and Readme file) needs to be prepared and submitted to ESO following the standard
Phase 2 preparation procedures. In
particular, please note that the
deadline for the submission of the
Phase 2 package applies for RRM runs as well.
- The names of OBs for execution in RRM mode must be preceded by the
RRM prefix (e.g. RRM_grb346+580_3x600s). They should not contain any spaces
or special characters, but only letters, digits, dashes, plus signs and/or
underscores.
- Once an activation has been successfully triggered, the OB executed
cannot be used for another activation.
- Besides the RRM OBs, the users should also prepare normal
ToO OBs in case
non-RRM observations are required: for instance, for follow-up of the RRM
activation (since with RRM only one OB can be activated), or if observations
of the target are desired when the 4-hour RRM deadline has passed (see
below).
- The ESO User Support Department
or the La Silla Science Operations
verifies the submitted material. The instructions on how to upload trigger
signals are communicated to the Principal Investigator of the programme
following verification of the Phase 2 package.
- To activate the RRM, an ASCII file must be received at the dedicated ftp
server in Garching with the following characteristics:
- Its name must be the same as that of the OB that needs to be
executed, preceded by a string of the generic form
[instrument]_[p2pp ID]_ (e.g. UVES_5291_RRM_grb346+580_3x600s).
Your p2pp ID is not your User Portal username, but rather a
number which will be supplied to you by your Support Scientist.
- Its content must be a single line with the J2000.0 coordinates of
the target. The format is hhmmss.ss for the right ascension,
sddmmss.s for the declination (e.g. 004727.32 -251738.3)
- The activation file must be uploaded to the relevant instrument
sub-directory, such as:
- /home/rrm/UVES/ for UVES activations,
- /home/rrm/ISAAC/ for ISAAC activations,
- /home/rrm/FORS1/ for FORS1 activations,
- /home/rrm/FORS2/ for FORS2 activations,
- /home/rrm/SINFONI/ for SINFONI activations
An analogous procedure exists for GROND activations.
- Along with the RRM trigger signal, accompanying RRM information,
including a finding chart, must be sent to Paranal or La Silla using established
Target of Opportunity (ToO)
procedures.
For RRM activations only, an email template, can be used as a substitute for
filling out the ToO activation webpage:
Do not attach the finding chart to
the email, but include a link to a webpage that contains the finding
chart in the comments section. For the time being, a simple activation
email (to either antu@eso.org for UT1, kueyen@eso.org for UT2 or
lasilla@eso.org for the 2.2m) with
the finding chart attached will also be accepted.
- Only requests from the end of evening nautical twilight to the beginning
of morning nautical twilight (i.e., received when the Sun is more than
12 degrees below the horizon) will activate the RRM.
- Any RRM activation arriving outside the time interval noted in the
previous point will be discarded with no trigger counted.
- It is the responsibility of the activators to ensure that the target is
observable, bright enough, and easy to identify by the night astronomer.
- To prevent long-term remnants in the detector that may affect future
observations, ISAAC RRM triggers of targets with objects brighter than J=9,
H=9, or K=9 within 2.5 arcmin from the field center will not be accepted.
- Any successful activation will be counted as an RRM
trigger, whether the requested observations could be successfully
performed or not.
- The RRM will only operate in Service Mode and activations arriving during
Visitor Mode observations will be discarded with no trigger counted. The only
exceptions are cases in which the OPC may have granted over-running status
over Visitor Mode observations for events with exceptional characteristics.
In such cases, ToO observations immediately following the RRM one have the
same override status over Visitor Mode.
- The requested instrument must be already in operation. Due to the need to
provide an immediate response to the event switch between telescope foci is
not possible. RRMs arriving for an instrument that is not in operation will be
discarded with no trigger counted.
- In case of gamma-ray burst RRM observations: the RRM should
only be used if the time since the GRB is shorter than 4 hours; after 4
hours the observations should be requested through the normal ToO
procedure. The user should have prepared normal ToO OBs (before the Phase 2
deadline!) for this to be possible.
- It is possible that the RRM status (
for Paranal or for La Silla)
does not allow an alert to be triggered, but that ToO
observations are possible during the same night (e.g. due to a focus switch to
the relevant instrument). If desired, these observations should be requested
through the normal Target of Opportunity (ToO)
procedures, and the proper ToO OBs must have been prepared. These ToO
observations, if successful, will be counted as a RRM trigger.
- Any desired immediate follow-up observations of a successful RRM trigger
must be requested through the normal ToO
procedure, since only one OB can be executed as RRM. Such a ToO request
can be already specified in the RRM alert email, or in a separate ToO request.
Also in this case, ToO OBs must have been prepared before the Phase 2 deadline
for this to be possible. The execution of such follow-up observations cannot
be guaranteed.
-
RRM data will be made available immediately to all the PIs of OPC-approved
GRB proposals in ToO and RRM for the current period, through a dedicated ftp account.
The username and password of this account are communicated to the corresponding
PIs at the beginning of each period. The default (12 months) proprietary period
will apply for the rest of the world, unless a shorter period has been specified
in the Phase 1 proposal.
- Any intentional misuse of the RRM (e.g. for the observation of events
unrelated to the science case in the approved proposal or for late-time
follow-up not justifying the use of the RRM) will result in the cancellation
of the program in question.
- The time accounting is performed in the same way as for
normal ToOs; if a program has used up all
its hours or number of (RRM) triggers, no more triggers will be accepted.
- The time used by a RRM is counted from the start of the OB that was
interrupted until the start of the first OB after the RRM OB.
- In special cases RRM runs may be allowed to indistinctly use either FORS1
or FORS2. In such cases only one trigger will be counted if both FORS1 and
FORS2 are activated at the same time. However, the time accounting will be
performed for both telescopes,. i.e. counting from the start of the OBs that
were interrupted by the triggers.
The state of the RRM process, and the result of an activation, can be
followed on one of these webpages:
The delay is of the order of a few
minutes. Requests will only be executed if the RRM state is ONLINE.
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