- Phase 2 Preparation
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- Observing conditions
- Service Mode Philosophy
- Service Mode Policies
- Phase 2 Instrument Table
- Service Mode Guidelines
- Special Procedures
- Visitor Mode Guidelines
- The p2 Tool
- Other Tools and Services
- Run Progress Report
- Post-observation Support
- Users Workshop 2018
- Using ESO Mac & Linux software repositories
- The User Support Department
Frequently Asked Questions
Observation Preparation
Do I need to account for overheads in my total exposure time when submitting Service Mode OBs?
Answer: Yes. Total allocated time = integration time + all standard operational overheads. To estimate your operational overheads, see the individual instrument User's Manuals and/or use the Execution Time Report function in the p2 tool.How many special calibration OBs do I have to submit?
Answer: You should assume that your science OBs will be executed completely independently of each other, possibly on different nights, and take into account that no calibration OB will be executed more than once. You should submit enough special calibration OBs to cover that situation. Example: if you need to observe and flux-calibrate six targets in a filter that is not supported in the calibration plan of the instrument, you need to provide six special calibration OBs to allow for the case in which each target is observed on a different night. This must be done so even if the same calibration star can be used for all the science targets. For assistance, contact the User Support Department (usd-help@eso.org).Can I specify different observing constraints(e.g. seeing, transparency) at Phase 2 than I specified in my Phase 1observing proposal?
Answer: You can relax your constraints to increase the chances of execution of your OBs (for example, if you specified Seeing = 1.0 or better at Phase 1, you can specify Image Quality that corresponds to V band Seeing at zenith of 1.2 or better at Phase 2). However, more stringent constraints (like Image Quality that corresponds to V band Seeing at zenith of 0.8 at Phase 2, in the previous example) are not allowed, as an essential ingredient of the long-term scheduling of Service Mode programmes over the semester is the constraints that users of approved programmes specified at Phase 1. Allowing more stringent constraints at Phase 2 would thus endanger the completion of even the highest ranked programmes. An allowed exception to this are OBs needed to flux-calibrate observations that can be mostly done under non-photometric conditions, provided that accurate flux calibration is needed for the scientific goals of the programme and that the execution time under photometric conditions does not exceed 20% of the allocated time.The values in the OB constraint sets that are selected (and approved) during Phase 2 preparation (and review) cannot be changed later during the observing period. This is explained in more detail in the Phase 2 Service Mode Guidelines web pages.How do I get my p2 username and password?
Answer: The p2 username and password correspond to the ESO User Portal username and password of the Principal Investigator (PI), or of the Phase 2 Delegate (in case the PI has delegated Phase 2 access to another User Portal registrant). If you as PI of a scheduled run, or as a Phase 2 Delegate, have forgotten your User Portal username and/or password please use the appropriate corresponding link(s) on the User Portal login page.If you have no accepted programs as PI but wish to learn the use of p2, you can use the p2 demo server set up for this purpose.
After reviewing my Phase 1 proposal, I have realized that I can observe a better set of targets than the ones I listed then. Since the scientific goal is the same, can I simply change the list of targets?
Answer: No. There are multiple reasons. One is to avoid duplication of observations unless scientifically justified and conflict/scooping between different scheduled programs. Furthermore, the allocation of time in Service Mode is made to balance pressure factor on each right ascension interval, derived from the distribution in the sky of the targets that the accepted programmes proposed at Phase 1. The Long Term Schedule that results from the time allocation process would thus be invalidated if changes of target were allowed at Phase 2, this is, after the time allocation has been made.
It is however possible to accept a limited number of target change requests in cases for which a sound scientific justification exists, such as the existence of new observations that demonstrate that a given object of the original sample had been misclassified and is not relevant to the purpose of the programme any more. Target change requests are reviewed by ESO to ensure the strength of the justification and also that there is no other approved programme that intends to execute observations of the new target in a similar configuration.
Target change requests must be addressed to the ESO User Support Department via a dedicated Target/Instrument Setup Change web form.
How do I prepare my Phase 2 proposal for APEX?
Answer: APEX does not use p2, but a web-based form. On the said form you will have to provide your email: please make sure that it is exactly the same as the one present in your ESO User Portal profile. The APEX Phase 2 deadline is the same as the P2PP deadline. Should you have any questions about your Phase 2 preparation, please contact ESO APEX support (apex-garching@eso.org).I have an accepted proposal which consists of a pre-imaging run and a follow-up multi-object spectroscopic (MOS) run. May I submit only the pre-imaging OBs now, by the Phase 2 deadline, and the spectroscopic OBs later?
Answer: Yes, you should submit only the pre-imaging OBs (i.e. no dummy MOS OBs should be submitted at the general Phase 2 deadline). ESO will make every possible effort to execute all pre-imaging as early as possible, and will release pre-images immediately. In effect all pre-imaging OBs will be treated as ``carry-under OBs'', meaning that they will be executed as soon as they are ready, even if that is before the period starts. For the Phase 2 proposers this means that it is important to submit pre-imaging OBs as soon as possible, even long before the deadline. The earlier valid OBs are submitted, the earlier the pre-images will be taken, and the higher the probability that follow-up MOS observations will be completed within the narrow window of opportunity.Can I directly interact with my contact scientist, rather than sending mail to usd-help@eso.org?
Answer: This is what will happen in practice even when you send an e-mail to usd-help@eso.org. We encourage you to use this e-mail address, rather than the private e-mail of your support astronomer, because user support astronomers have other professional commitments that sometimes cause them to be away and have limited access to email and, especially, to the tools used in ESO operations, which may cause delays in addressing problems. If you send your request to usd-help@eso.org we will ensure that it is always given prompt attention by an expert on the instrument that your run uses, even in periods when your contact scientist cannot deal with it.What is the accuracy of the UTs pointing and tracking?
Answer: The UTs have a pointing accuracy of 3 arcsec RMS, driven by the guide star catalogue accuracy. The expected tracking accuracy under nominal wind load is 0.1 arcsec RMS over 30 minutes when field stabilization is active. The UTs also have the capability of tracking targets with additional velocities (e.g. Solar System targets) under full active optics control. Proposers who need this capability should specify the additional velocities in RA and Dec for their targets. Please check here for further details on UTs performances.
Scheduling
My run can be executed more efficiently if my OBs are executed one after another, skipping the acquisitions for the latter OBs. Why cannot I ask for such a procedure for service observing?
Answer: There is no guarantee that user specified conditions will last long enough to complete any given OB sequence. Furthermore, there may be different priorities between programmes that have targets observable under similar RA range. Thus breaking down a sequence of OBs often improves overall operations efficiency by allowing the execution of OBs best matching the external conditions and scientific ranking. Therefore, to maintain the flexibility needed to adapt to changing observing conditions and to maximise operations efficiency, ESO requires that all Service Mode OBs be treated as independent observations with independent acquisitions. If the constraints change during the first hour of observation your OB will be repeated without any penalty or cost to your run.Having to split my OBs to make them compliant with the rule that no Service Mode OBs could last longer than one hour implies much more execution overhead. Wouldn't it be more efficient to allow longer OBs?
Answer: Experience has shown that longer OBs make Service Mode observing less efficient, rather than more. The reason is that, the longer an OB, the more likely it is that the external conditions go outside the acceptable range specified in the Constraint Set. Since OBs executed outside constraints must be rescheduled and re-executed, longer OBs imply not only a higher fraction of OBs to be re-executed, but also a larger amount of time wasted in the execution of OBs failed because of the degradation of external conditions.Still, some programs may have scientific reasons that require OBs longer than one hour to be scheduled. In such case, a waiver request justifying the need for a longer execution time must be submitted to ESO. When sufficiently justified, these requests are accepted under the condition that the OB will be considered as executed within constraints even if the conditions degrade after the first hour of execution.
Is it possible to monitor the progress of my program?
Answer: Yes. Both the Run Progress Reports page and the Science Archive query form allow you to access updated information on the progress of your observations. In p2 it is now also possible to see the current status of OBs. More information about OB statuses visible in p2 is available here.If my programme cannot be completed by the end of the Period, can I ask to have it carried over to the next one?
Answer:If your programme obtained a Priority Class A and has not been completed by the end of the Period, it will be considered as a candidate for carryover to the next Period without you having to request it. In this case you will get a notification from User Support Department about the possibile carryover at the time the Call for Proposals for the next observing period is issued. This is not possible at present with Priority Class B or C programmes, which are terminated at the end of the Period regardless of their status of completion. Please see our page on the philosophy and scheduling of Service Mode programmes for more information. If you had a Class B or C Programme and you see that the end of the Period is approaching without it being near completion, you are strongly encouraged to resubmit it as a new observing proposal.How can I know precisely on what dates my Service Mode observations will be executed?
Answer: A key feature of the flexible scheduling approach followed at the ESO Observatories is that Service Mode Programmes do not have definite dates assigned to them. Rather, they are executed according to the external observing conditions, some of which are unpredictable, like the sky transparency or the seeing. Only in this way it is possible to ensure that each of the many programmes approved every semester in Service Mode is executed under the conditions that are necessary for its scientific goals.The Principle Investigators and their Phase 2 and/or data delgate(s) can subscribe to receive e-mail notification whenever one of their OBs has been executed. To subscribe login to the (Garching Night Log Tool) gNLT overview page using your User Portal credentials.ESO has communicated me the allocation of time to my run, but only in class C. Is it worth it to prepare any Phase 2 material at all?
Answer:Yes! ESO selects class C programmes from those that did not get a high enough rating to be above the time allocation cutoff line, but whose constraints made them schedulable under a very wide range of conditions (i.e., in intervals of bad seeing, with moon, or under poor sky transparency conditions). Higher rated runs normally have more stringent constraints and, when the conditions are below average, only class C runs may be executable. Due to the high pressure factor at ESO telescopes, the scientific quality of class C runs is normally still very high, and experience shows that Service Mode class C programmes, which would not have been scheduled in classical Visitor Mode, have produced very valuable scientific results.
Data Distribution
I see from the Web that my pre-imaging OB has been completed. What do I have to do to get the data?
Answer: Nothing. A special data quick-release process is in place and you should be contacted with instructions about how to retrieve your data as soon as they are available, usually the next working day.I have seen in the Run Progress Reports web pages that some data have been obtained for my programme. Can I obtain the data already?
Answer: Yes! As of 01 April 2008 Principle Investigators, as well as their collaborators to whom Data Delegtion is assigned in User Portal, can download their proprietary raw data from the Science Archive Facility as soon as the data have been ingested into the archive. For complete details, including important details regarding the proprietary period for the data see the Data Release page.I would also like to see the pipeline reduced data. How is that possible?
Answer: Until October 2011 the PI-packs accessible via User Portal account contain raw data, associated calibrations and pipeline products. For observations taken after October 2011 ESO no longer provides PI-packs. The raw data can still be accessed via the archive and the associated calibrations and ancillary files are available for download via CalSelector archive service.
Some instruments however have now Internal Data Products, pipeline reduced science data, released by ESO. Links to those data products, as they are created, become available via gNLT run progress pages, via dedicated Query Forms in the ESO Science Arhive, as well as via the web-based Science Archive Portal. For the availability of reduced science data with the ESO pipelines please consult the ESO Science Archive Facility webpages.
Frequently Asked Questions related to X-SHOOTER
I am mainly interested in the NIR arm. Can I provide a finding chart produced from a NIR image?
Answer: In X-Shooter the acquisition is done through an optical detector. Therefore you have to provide a finding chart produced from an optical image.Do I need to build my OBs such that the execution times in the three arms are identical, in order to be sure the telescope offset is applied only when all exposures are completed?
Answer: No. The telescope offset is applied only once the longest exposure series is completed.Is it possible to stare at the object in UVB and VIS while nodding in the NIR?
Answer: No, this is not possible. In X-Shooter the offset applies rigidly and simultaneously to all arms.Is it possible to bin (2x1, 1x2, 2x2) in the NIR arm?
Answer: No, this is not possible. Only 1x1 read-out is offered.Is it useful to attach arc exposures to night time science observations to improve the wavelength calibration accuracy?
Answer: This probably makes sense only in the UVB arm, where there are very few night sky lines. For the VIS and especially NIR ar the number of night sky lines is sufficient to guarantee a good refinement of the wavelength solution achieved with the day-time arcs.When do I start to be background dominated in the NIR?
Answer: In the H band spectra a background-dominated (sky+diffuse background) between the OH lines for exposures longer than 10 minutes.How long does it take typically to saturate the night sky lines in the NIR?
Answer: With the Threshold Limited Readout (TLR), sky line saturation is not an issue. We have exposed 30min without any problem. Saturation is only a problem for very bright targets that would go over 100,000 electrons in less than about 2 seconds. Basically, with the TLR technique, the counts are computed from the count rate, deduced using all the unsaturated readouts. The detector is read-out every 0.6 sec, the counts accumulated and the count rate used to compute the counts one would reach in the exposure time if there were no saturation. This corresponds to having effectively different exposure times for each pixel.My target is not visible in the optical. How do I acquire it into the slit?
Answer: You can use a blind offset from a field star. To set this up, you can use the ObsPrep tab in the p2 tool, as described in the tutorial. This tool will also modify the OBs changing the acquisition coordinates from those of the target to those of the acquisition star, and changing the OFFSET.RA, OFFSET.DEC fields of the acquisition window in p2. The ObsPrep tool will also create instrument-compliant Finding Charts showing the location of the acquisition star, as well as the target.Do I need to provide specific OBs for the observation of Telluric Standards?
Answer: Starting from Period 101, the Observatory will not supply telluric standard stars anymore. Users that require OBs for telluric coorection need to submit them in a concatenation. The corresponding execution time must be taken into account at Phase 1.What is the meaning of the Position Angle for the Integral Field Unit?
Answer: The Integral Field Unit (IFU) is rectangular. The position angle (PA) specifies the direction of the long side. So, PA=0 means that the IFU will be placed North-South.Is it possible to have OBs longer than one hour with X-Shooter?
Answer: Yes, this is in principle possible and, as for all other VLT instruments, it requires the approval by the Observatory. The request needs to be sent as a waiver. See this web page for more details.The user must be aware of the fact that the correction for flexure is only made at the start of the exposure and may degrade over time. However, the degredation is acceptable up to about an hour and 15 minutes.What is the meaning of the SEQ.IFU.WLGT in the template for Integral Field Unit acquisition SHOOT_ifu_acq ?
Answer: In IFU mode there is no correction for atmospheric dispersion. The two ADCs that come after the IFU in the light path are set to their OFF position, where they do not disperse light. Therefore, the user has to choose which wavelength will be kept fixed at the centre of the IFU during the observations. This is done through the SEQ.IFU.WLGT parameter. By default, this is set to the middle of the atmospheric dispersion range (470nm), but it can be set to any value within the X-Shooter range. To minimize the losses, we recommend to place the IFU along the parallactic angle. Also, the users should be aware that, at high airmasses, the amplitude of the dispersion is larger than the 4 arcsec long side of the IFU field. Therefore, depending on the particular choice of SEQ.IFU.WLGT, losses can occurr at either edges of the spectral range.After the acquisition I would like to add several science templates using different slits. Is this possible?
Answer: Yes, this is possible. The various slits are placed very accurately on the right position, and hence there is no need for re-aquisition. You can use any slit you wish after the acquisition.Will I get pipeline reduced data for X-Shooter? To which level?
Answer: The X-Shooter pipeline available with the Esoreflex package provides reduced spectra, which are extracted (1D), wavelength and flux calibrated. Telluric correction can then be performed with the molecfit tool. The fully reduced spectra are also available for X-Shooter a few days after the observations are taken.What is the minimum integration time in the NIR?
Answer: The minimum DIT is 0.665 seconds. This is the time the IRACE controller takes to read-out the full detector. Entering shorter (or even zero) DIT times in the OBs will always produce effective DITs of 0.665 seconds.I have a target which is very bright in the NIR, but no so much in the optical. Even with the shortest DIT the object is going to cause strong remnants in the NIR arm. How can I solve this problem?
Answer: In principle one can set the NIR slit to the "blind" position, which would effectively close the NIR spectrograph entrance. However, this is not offered in Service Mode. If you really need to do this you must apply for Visitor Mode.