Rules/Hints for GROND use by other MPI groups

This document describes some rules for the use of GROND by other groups from Max-Planck Institutes.

General Remarks

• GROND is an imaging instrument which allows simultaneous imaging in 7 bands: Sloan griz in the optical and JHK in the NIR. GROND is permanently mounted at the MPG/ESO 2.2m telescope on La Silla. Instrument switches between GROND and WFI/FEROS take of order 1 min. Details of the instrument are described in a paper published in PASP 120 (2008) 405-424.
• GROND has been developed and built by MPE Garching and the Thüringer Landessternwarte Tautenburg. Its main objective is to perform follow-up observations of gamma-ray bursts. Gamma-ray burst observations are performed in a nearly-automatic fashion using the Rapid-Response Mode of ESO. GROND-observation triggers happening fall under ESO-MPIA and MPE-MPIA contracts, and the corresponding time (15% of the telescope time) is bought by MPE from ESO.
• GROND is not an official ESO instrument , and thus not offered during ESO time. Non-GRB observations can only be proposed for MPG time with the PI being from an MPI institution.
• GROND was built for automatic operation, and though it is using VLT-compliant observing blocks, usage in manual (visitor or service) mode requires special provisions and knowledge. Non-GROND-team observers are encouraged to familiarize with GROND operation BEFORE arriving on La Silla. Help by GROND observers on La Silla may be available, but is not guaranteed.
• GROND is, in general, offered for use to any staff member of any Max-Planck institute. Since our manpower is seriously limited, both the documentation as well as the "user-friendliness" for visitors is in a very poor status. We therefore urge potential users for patience. In case of questions don't hessitate to contact Jochen Greiner (jcg@mpe.mpg.de).

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  Specific conditions

• Astronomers from other MPI groups are welcome to use GROND for their scientific projects (with the above caveat). Technically, this has to be done by applying via standard proposals for 2.2m observing time during MPG periods.
• The GROND team requests to be involved in any science topic which involves the use of the GROND instrument. The level of involvement will vary on case by case, and is described below. Jochen Greiner as representative of the GROND team (jcg@mpe.mpg.de) should be contacted prior to submitting the proposal in order to discuss the involvement, and moreover agree on the feasibility, details of the execution of the observation and the delivery of the data.
• MPE and Tautenburg have defined a number of high-priority non-GRB science topics. If any of those topics is proposed by other MPI astronomers, the GROND team reserves the right to refuse collaboration if the added value by that proposal is considered to be not important for the project. In all other cases, the involvement of the GROND team can range from pure co-authorship (if the science topic is not covered by GROND interests) to various levels of collaboration on data acquisition, analysis and/or interpretation. For large programs which extend over several MPG periods, it may be useful to involve the GROND team already in the planning process.
• Once a proposal topic has been discussed with the GROND team, and the level of collaboration of the GROND team has been defined, the actual proposal should be submitted following standard MPIA rules and deadlines.
• After acceptance of the proposal, the GROND team should be contacted to agree on the execution of the program. In general, one member of the GROND team will perform the observations. The OBs should be prepared by the PI using p2pp, obeying the same deadline as for WFI/FEROS programs. ESO will assign program-IDs for each accepted program. The GROND instrument package for p2pp has been delivered to ESO, so should be included in the official p2pp release. If you prepare your first GROND observation, check the hints for preparing the OBs.
• Data are stored on a GROND computer on La Silla. In regular intervals, data are shipped to Garching (via transportable disks). Since typical projects do not fill a full night, but extend over several nights, sorting of the data according to program-ID has to be done. This will be performed at MPE Garching after data shipment. Data delivery to the PI will be done either via ftp, or DVDs. The whole process may easily take 4-6 weeks or more, so again patience is requested.
• The GROND team has established a data reduction pipeline which is continuously being finetuned. This data reduction includes bias subtraction, flatfield and distortion correction, shift-and-add of dithered NIR images, astrometry, and a basic source detection and PSF-photometry. While this pipeline is presently tuned for GRBs, it is intended to extend it for generic GROND observations. In the future, these reduced data may be shipped together with the raw data.
• As mentioned above, any publication using GROND data should contain representatives of the GROND-team, the number of which will depend on the level of involvement/collaboration. Also, a reference to the GROND instrument paper should be made:
  Greiner J., Bornemann W., Clemens C., et al. 2008, PASP 120, 405

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  Data access

• According to the agreement with ESO, data should NOT be ftp'ed from La Silla to Germany - and most likely even cannot be ftp'ed: per night, you can gather up to 25 Gb data!
  Data are stored locally on GROND's own RAID array in La Silla, and are shipped to Garching about once every three weeks. In Garching, data will be checked for completeness, and then are stored in the AFS system of the Campus' Computer Center (RZG).
• Make sure that you are registered on our system (send email to Lars Klose - lklose@mpe.mpg.de): you can check the availability of your data here). As a rule of thumb, you should be prepared to get your data not earlier than 4 weeks after the observation.
• The preferred way for you to get access to your data is to install/mount AFS on a (your) local computer - then you will be able to see the data directly, and a simple "cp" command will copy the data to your local computer (if this is what you want).
  To find out the full directory path, go to the start page, click on the corresponding users group you belong to, and then on the proper observation period.
• Alternatively, if there is no afs machine at your institute, you can either
  • apply for an account at the Rechenzentrum Garching (ask either Stefano Zibetti or Bertrand Goldman for help, they have done this in the past): go to http://www.rzg.mpg.de/, and follow the link "New Users" in the left column, or
  • use the accounts of one of your collegues