ING Instrumentation Working Group ================================= Minutes of the meeting held Fri 5 May 2000 ------------------------------------------ Location: Department of Physics and Astronomy University of Kent at Canterbury, UK Time: 10.00 - 17.00 Present: Dr R G McMahon (Chair) (RGM) Dr S Arribas (SAM) Dr G B Dalton (GBD) Dr V S Dhillon (VSD) Dr S F Green (SFG) Dr N A Walton (Secretary) (NAW) In Attendance: Prof C Dainty (ICST) (CD) Dr P Doel (ICST) (PD) Dr R M Sharples (Durham) (RMS) Apologies: Dr K Kuijken (KK) Papers: these were distributed at the meeting a. Minutes of the IWG 1 Nov 1999 meeting b. Action items outstanding from previous IWG's c. Message from Thijs van der Hulst concerning OASIS shortly available on the ING IWG WWW pages at http://zwolle.ing-slo.iac.es/IWG [subject to authors permission] d. View graphs from NAW over viewing current ING instrumentation (gzipped ps file) e. View graphs from SAM describing GTC and LIRIS f. View graphs from PD describing the coronograph g. View graphs from CD over viewing the Laser site characterisation study and LGS proposal h. View graphs from RMS describing TEIFU and IR-TEIFU i. View graphs from RMS describing MOSAIC Abbreviations and Glossary: 2dF The 2deg prime focus fibre fed multi-object spectrograph capability on the AAT AAT 3.9-m Anglo Australian Telescope ALFA The LGS AO system on the 3.6-m Calar Alto telescope AO Adaptive Optics CFHT 3.6-m Canada France Hawaii Telescope ELECTRA The Durham multi segment mirror AO system - this will form the heart of NAOMI ESO European Southern Observatory FOV Field of View LGS Laser Guide Star IFU Integral Field Unit INGB Isaac Newton Group Board INGRID a near IR 1kx1k camera for the WHT INT 2.5-m Isaac Newton Telescope LIRIS a near IR spectrograph being built by the IAC for the 4.2-m WHT NAOMI The optical/IR AO system for the WHT TAURUS The Fabry-Perot imaging spectrograph, mounted at the Cassegrain focus of the WHT TEIFU Thousand Element Integral Field Unit - an IFU to feed WYFFOS TTF TAURUS tunable filter (for low spectral resolution, wide field imaging) UES The WHT's Utrecht Echelle Spectrograph UKIRT 3.8-m UK Infra Red Telescope UltraDAS The ING's new Data Acquisition System VLT ESO's 4x8-m Very Large Telescope WHT 4.2-m William Herschel Telescope WYFFOS The WHT's Nasmyth mounted, fibre fed, spectrograph INTRODUCTION 1. Introduction: welcome 1.1 RGM noted, that because Chris Dainty would not arrive till 2.30pm, items 3 (The WHT and WYFFOS development path) and 4 (Update on new instrument proposals) on the agenda would be discussed last. 1.2 RGM noted that CD, PD and RMS were in attendance to provide input into the discussions on AO developments at the ING. MATTERS ARISING 2. RGM highlighted the action points from the minutes of previous meetings. 2.1 Matters arising from meeting of April 6 1999 2.1.1 [IWG4-99/1.26] NAW reported on informal discussions with the Durham group. In principle Durham have no objections to offering TEIFU as a common user instrument. The main proviso would be that ING or other funding is found to cover the costs of bringing TEIFU up to common user status. RMS noted that TEIFU might be too complicated to easily support. If OASIS were to become operational at the ING, then probably only the IR-TEIFU would become common user. More detailed negotiations between the ING and Durham are required. [ACTION: RGMR - ONGOING] 2.1.2 [IWG4-99/1.27] The possibility of an AO feed to UES. This may be provided as part of the MOSAIC concept. NAW is to present an outline of possible High-Resolution spectroscopy instrumentation development options for the WHT at the next IWG [ACTION: NAW - ONGOING] 2.1.3 [IWG4-99/3.7] AF2/WYFFOS J+H upgrade plan being developed. This item was discussed more fully under item 3.1 - new action resulting. [ACTION: NAW - CLOSED] 2.1.4 [IWG4-99/7] ING Sheffield Conference (Apr 1999). NAW reported that the submitted papers were in the process of being placed on the ING WWW server under the new IWG pages - see [IWG11-99/3.3.2] [ACTION: NAW - CLOSED] 2.2 Matters arising from meeting of November 1 1999 2.2.1 [IWG11-99/2.3.5] The IWG asked that a overview sheet be provided listing the capabilities and performance specifications of NAOMI. NAW reported that the ING NAOMI Project Scientist (Chris Benn) had now made this available on-line at http://www.ing.iac.es/~crb/wht/ao.html [ACTION: NAW - CLOSED] 2.2.2 [IWG11-99/3.3.2] The IWG expressed some technical queries as to how the Coronograph for NAOMI would function in the optical regime (in particular how would the visible light get to the wavefront sensor?). This was answered by PD during discussion under item 3.3. [ACTION: NAW - CLOSED] 2.2.3 [IWG11-99/6] The IWG considered it important that the papers presented at the ING Sheffield Conference (Apr 1999) should be made available on-line as soon as possible. NAW reported that the papers had been passed onto Phil Charles (NAR editor) at the beginning of 2000 and that the papers were in the process of being placed on the ING WWW server. [ACTION: NAW - ONGOING] 2.2.4 [IWG11-99/10.1] NAW reported that the ING mailing list had been updated to include a wider audience, including the IR community. [ACTION: NAW - CLOSED] 2.2.5 [IWG11-99/10.2] The IWG noted that more information concerning the ING instrumentation programme should be issued to the community. It was hoped that informed feedback from the user community would be promoted. NAW reported that the purpose and membership of the IWG was given in the ING Newsletter. [ACTION: NAW - CLOSED] 2.2.6 [IWG11-99/10.2.1] Develop IWG web pages on the ING WWW server. NAW noted that preliminary WWW pages were now available at http://zwolle.ing-slo.iac.es/IWG. These would be incorporated into the 'new look' ING www pages due to go live end June 2000. The IWG looked forward to the improved functionality that the re-designed ING WWW pages would offer. [ACTION: NAW - CLOSED] 2.2.7 [IWG11-99/10.2.2] Issue (via the ING Bulletin) an overview of current and proposed ING developments and enhancements to the community. NAW and RGM AGREED that a paper to this effect should be written for the next ING Newsletter. [ACTION: NAW/RGM] 2.2.8 [IWG11-99/10.2.3] Issue the IWG minutes on the ING IWG WWW pages. NAW reported that these would be added to the IWG WWW pages. [ACTION: NAW - ONGOING] 2.3 There was a brief discussion on the importance of well designed and accessible WWW pages. PD requested that basic information concerning the ING telescopes be made available. NAW noted that much of this was available on the internally accessible ING Intra-net. [IWG5-00/2.3 ACTION: NAW] To investigate whether telescope engineering information could be made more generally accessible via the ING WWW pages. 2.4 RGM suggested that important announcements from the ING to the community should be issued in the emailed ING Bulletin. He noted that an effective dissemination might be via the PPARC ASTRONEWS mail exploder. [IWG5-00/2.4 ACTION: NAW] To action distribution of ING Bulletin via the PPARC ASTRONEWS mail exploder. 2.5 The minutes of November 1 1999 were read and accepted. UPDATE ON CURRENT ING INSTRUMENTATION DEVELOPMENTS AND ENHANCEMENTS 5. NAW gave a brief presentation on the current on-going ING developments and enhancements. 5.1 INGRID: NAW reported on it's successful commissioning at the WHT Cassegrain focus in March 2000. Performance reaches specification. A significant number of proposals have been received to use INGRID in semester 2000B. It will be popular both with NAOMI and stand alone. RGM noted that at Cassegrain, with a field of 4.3 arcmin, INGRID gives a significant survey capability, much in excess (x4) of that offered by UKIRT+UFTI. NAW noted that the INGRID filter set - purchased through the Gemini consortium, have been delivered with surface irregularities. Their performance is being investigated including the possible effect on the imaging performance with AO. [ http://www.ing.iac.es/IR/INGRID ] 5.2 NAOMI: NAW reported that it is on schedule for on sky commissioning to begin mid July 2000. NAOMI has been delivered to Durham for final integration before being shipped to La Palma at the end of June. RMS noted that there had been several slip-pages in the delivery of NAOMI from the UKATC to Durham. The schedule in Durham was now very tight. To meet the July schedule, NAOMI had been de-scoped. This functionality would be added to NAOMI towards the end of 2000. [ http://www.ing.iac.es/~crb/wht/ao.html ] 5.3 UltraDAS: NAW reported that the project scope has been expanded to include IR detectors at the ING, initially INGRID. There have been some delays due to problems with the interface driver delivered by SDSU for the PCI hardware. However the SBUS based system has now been implemented for the WFC and the 2 chip EEV42 CCD mosaic (used at UES and WHT PF). The system will next be implemented for the ISIS red and blue arm detectors using SBUS SDSU interface cards. It is expected that all ING detectors will be upgraded to use UltraDAS (SBUS and later PCI based versions) by Q2 2001. 5.4 Red CCDs: The ING is formally part of the UH/LL/MIT CCD development programme for 'Red' sensitive CCDs. Delivery of these devices is scheduled for Q3 2001. An early test device had been received at the ING in Apr 2000. Plans were advanced as to the design of dewars and electronics for the expected 2-3 science grade devices. 5.5 LIRIS: SAM gave a brief overview (view graphs) of this instrument and it's capabilities. SAM reported that commissioning is foreseen for Apr 2001 at the WHT. The IWG were interested to note the MOS capability of LIRIS which would be fairly unique. SAM reported that LIRIS has a MOS changer which can hold 10 masks each of which can contain up to 10 slits. The MOS changer is integral to LIRIS and thus the slit masks cannot be changed without warming up the entire instrument. [Confirmed by email from SAM: 12 May 2000] 5.5.1 The IWG expressed interest in what will be a powerful near IR multi function spectrograph. They asked for a comparison of the performance that WHT+LIRIS would provide compared with UKIRT+UIST and VLT+ISAAC. [IWG 5-00/5.5.1 ACTION: NAW/SAM] To provide an overview of the WHT+LIRIS capability compared with UKIRT+UIST and VLT+ISAAC. 5.5.2 The IWG inquired what access to LIRIS would be available to the UK and NL communities. NAW and SAM reported that no formal agreement currently exists between the ING and the IAC as to access to LIRIS. [IWG 5-00/5.5.2 ACTION: NAW/SAM] To report on progress on discussions as to access, status of LIRIS. 5.5.3 Pre-empting the discussions under item 3, the IWG inquired whether LIRIS could be feed by AO, and in particular IR-TEIFU. [IWG 5-00/5.5.3 ACTION: SAM] Report on whether IR-TEIFU could feed LIRIS. [ http://www.iac.es/proyect/LIRIS ] LDSS/TAURUS ADOPTION AND VISITOR INSTRUMENTS 6. NAW gave a brief update on the status of the LDSS/TAURUS adoption proposals that had been received in response to the Jul 1999 LDSS/TAURUS Announcement of Opportunity. NAW also overviewed the main visitor instruments currently in use on ING telescopes. RGM mentioned that the recommendations made at the 11-99 IWG subsequently been accepted by the INGB at it's 12-99 meeting. 6.1 The Durham/IoA LDSS-2 bid (PI: Richard Bower) was discussed. LDSS-2 ownership has been transferred to Durham/IoA. It left La Palma after its last Semester 2000A run at the WHT. The team aim to deploy LDSS-2 at the Magellan telescope for 2-3 years. After that time it may return as a visitor instrument to the WHT. 6.2 The IoA TAURUS (PI: Richard McMahon) bid was discussed. TAURUS ownership has transferred to the IoA. It will not be in use at the ING in Semester 2000B. The IoA team may implement some additional coronographic capability in conjunction with Meaburn at Manchester. 6.3 CIRSI: the IoA panoramic near IR imager is currently used at the 2.5-m Du Pont in the B semester and the ING in the A semester. RGM noted that a small scale public access J+H band survey was being initiated with INT+CIRSI in semester 2000A. RGM commented that he is investigating the best mechanism to increase the use of CIRSI in survey mode - probably using it at the INT. [ http://www.ast.cam.ac.uk/~optics/cirsi/ ] 6.4 SAURON: this integral field spectrograph continues in use at the WHT. In future years the Leiden/Durham/Lyon team (PI: Tim de Zeeuw) may consider offering it for use by the community on a shared programme basis. [ http://www-obs.univ-lyon1.fr/~ycopin/sauron.html ] 6.5 SCAM: ESTEC's (PI: Mike Perryman) STJ based camera has been offered to the community on a collaborative basis in Semester 2000B at the WHT. It currently consists of a 6x6 array, with a energy resolution of ~8 at 5000A. NAW reported that the possibility of feeding each pixel with a fibre from AF2 is currently being investigated. [ http://astro.estec.esa.nl/SA-general/Research/Stj/STJ_main.html ] WIDE FIELD IMAGING AT THE ING 7. A Wide Field Imager for the WHT/INT has been suggested as a possible development. The IWG discussed the merits of this development route. 7.1 NAW commented that this had been previously discussed in the context of PPARC's UKIRT/INT wide field IR/Optical debate that occurred in the summer of 1998. At that time the GBFC/AC decided to fund the UKIRT WF camera (at a cost of UKP 5.2M(!)) and decided that they did not wish to fund a new large optical CCD camera at either UKIRT or the ING. The development plan for the ING does not currently include an option for further development of WF imaging. Little interest in WF imaging development at the ING was expressed during the Apr 1999 Sheffield Instrumentation conference. However, recently, some interest has again been expressed in a WF camera (especially for the WHT). 7.2 RGM noted that since the 1998 discussions, which resulted in approval for the UKIRT WF upgrade, VISTA won funding from JIF. Therefore by 2003-4 the UK will have access to 4-m WF optical and IR imaging in the south (through VISTA) and in the north IR imaging (with UKIRT+WFCAM). At present optical WF imaging is provided by INT+WFC. This will not be a premiere facility. However, it was noted that the UK might be able to gain access to 4-m optical imaging with CFHT+MEGACAM (in exchange for IR time with UKIRT+WFCAM). 7.3 The IWG AGREED that further investment in WF optical imaging on the WHT would now be inappropriate. To embark on a major WF project now would be too late, and seriously affect development in the AO area. Exploitation of AO will be more important in the long term - both to leverage the major investment in NAOMI and also as a technological input into future 30-m+ ELT's. 7.4 RGM raised the question of WF scale. In order to undertake survey work, imagers with FoVs of at least 1 sq deg are required. However, to act as 'finders' for 8-m telescopes, smaller fields suffice. Most 8-m class telescopes (e.g. Gemini, GTC) will have instruments with fields of 10 arcmin or less. Thus, the WHT already has instruments in the Optical (PF imager - 16 arcmin) and near-IR (INGRID - 4.3 arcmin) which well match the 8-m fields. 7.5 GBD noted that the WFC/WFS on INT is sufficient to support the proposed UKIRT JHK large scale survey, noting that UKIRT+WFCAM would not come on line until 2003. 7.6 SAM stated that Spain does not have a large active community of researchers active in large scale imaging. He noted that the present WF imaging provided by the WHT and INT+WFC was well matched to the GTC. [VISTA: http://www-star.qmw.ac.uk/~jpe/vista/ ] [UKIRT WFCAM: http://www.roe.ac.uk/atc/projects/wfcam/index.html ] RATIONALISATION OF ING INSTRUMENTATION 8. The IWG considered instrumentation rationalisation at the ING. NAW commented that in order to ensure that the operations cost of the ING is as economic as possible the JKT and INT instrumentation suite has been rationalised. 8.1 FOS-1: To continue this process of rationalisation at the INT, the ING wishes to finally de-commission FOS-1. This instrument had been upgraded with a larger blue sensitive Loral CCD. However, the throughput of the upgraded system was 50% lower than expected. There had been almost no demand for this instrument over the last four semesters. Most programs requiring FOS could be carried out using either INT+IDS (albeit with two exposures to overcome the 2nd order problem) or with WHT+ISIS. 8.1.1 NAW noted that the removal of FOS-1 would enable easier access to the Cassegrain focus of the INT - important when mounting fibres to feed echelle spectrographs such as MUSICOS. Savings would be made through not having to train staff to operate and maintain FOS-1 8.1.2 After a short discussion the IWG AGREED that FOS-1 should be decommissioned. VSD suggested that FOS-1 might be of some use to the Liverpool Telescope [IWG5-00/8.1.2 ACTION: NAW] to investigate whether FOS-1 might be of use at the Liverpool Telescope. 8.2 WHT: NAW and RGM noted that the instrumentation suite at the WHT had been recently rationalised by means of the transfer of LDSS-2 and TAURUS-2 to private ownership. 8.2.1 NAW presented the current imaging and spectrographic capabilities offered at the WHT. It was noted that there are a significant number of new instruments that will be deployed in the next 1-4 years. 8.2.2 The IWG commented that with the arrival of INGRID, NAOMI, and possible further AO instrumentation, the WHT's package will need to be further reviewed. 8.2.3 There was a brief discussion on instruments that might possible loose their competitive edge. This focussed on UES and INTEGRAL. Concerning INTEGRAL, SAM noted that: i) any trade-off between these Integral Field instrument concepts requires a detailed comparison including their relevant capabilities (spatial and spectral), their performace, operations/commissioning costs, etc. ii) OASIS/TEIFU offer capabilities which are complementary to the already existing INTEGRAL system, iii) OASIS and TEIFU may overlap their capabilities. Following i) this requires a detailed analysis but, in principle, TEIFU makes use of the already existing WYFFOS spectrograph (minimizing operation and comissioning costs) and it seems to be the right approach to move to the infrared. The capability offered by UES may be superseded by the PSSP (Planetary and Stellar SpectroPolarimeter) spectrograph (assuming that is funded - PI: Sean Ryan, OU). 8.2.4 The IWG AGREED that the capabilities of the instrumentation suite at the WHT needs to be continually reviewed, especially with the arrival of new instrumentation. [IWG5-00/8.2.4 ACTION: NAW] Generate comparisons of instrumental capabilities considering existing, in construction and proposed instrumentation. [current ING instruments at http://www.ing.iac.es/INGinfo/instruments.html ] NETHERLANDS INSTRUMENTATION ISSUES 9. NL instrumentation developments of interest to the IWG. NAW reported on the email received from Thijs van der Hulst (NL OASIS PI). This stated that there is strong support from the NL community for the OASIS instrument, there being significant and broad science to be carried out with this instrument in conjunction with NAOMI. Thijs noted that an LGS would significantly increase the scientific output and use of OASIS as an LGS would significantly increase the sky coverage available for AO observations. NAW noted that the PN spectrograph will commission on the WHT Q1/2 2001. [ PN spectrograph: http://www.aao.gov.au/local/www/pns/pns.html ] SPANISH INSTRUMENTATION ISSUES 10. SAM provided an update (view graphs) on Spanish instrumentation developments of interest to the IWG. 10.1 GTC: First light will be end 2002 with two Day One scientific instruments fully commissioned at the end of 2003. Canari-Cam (2-26um) will be one of the two instruments. The budget for the instruments is currently 9M Euros with 1320 hours of guaranteed time. [ http://www.gtc.iac.es] INSTRUMENTATION OPTIONS FOR THE WHT 3. The afternoon session was mainly devoted to upcoming instrumentation for the WHT focusing on AF2/WYFFOS and AO. 3.1 NAW gave a brief overview of the current upgrade path envisaged for WYFFOS. 3.1.1 Small fibres are being implemented - 1.6 arcsec fibres replacing the current 2.7 arcsec ones. The new fibres are continuous run with no breaks. Throughput is expected to be at least one magnitude better. This upgrade is progressing well, with commissioning expected March 2001. 3.1.2 In discussion NAW indicated that active autoguiding may be implemented with the new small fibre unit. At present, only manual autoguiding is possible - the semi-coherent bundles view a number of fidicual stars. The ING is investigating a coherent bundle to be placed by the AF2 robot at a guide star in the AF2 field. The coherent bundle will feed a standard ING autoguider head located at the PF and provide X-Y errors to the TCS. Rotation error correction will still be done manually by means of the semi-coherent guide bundles. 3.1.3 RMS noted that manual guiding was still used at the AAT+2dF, autoguiding proved to be too difficult to implement. 3.1.4 RMS and GD queried the quality control procedures being employed at the ING to ensure consistent high quality fibre production. NAW indicated that in principle the same procedures were being followed now as with the RGO/Durham production of the large fibres. Knowledge in production had been transferred before the closure of the RGO. Some improvements have been made - the alignment jig to position the prisms at the PF input end of the fibres is more sophisticated than used previously with the large fibres. Throughput of each fibre will be measured at every stage of production and fully logged. The IWG suggested that the ING's AF2 fibre team contact staff at the AAO who are presently involved with fibre production for the 6dF project. Useful information transfer may result. [IWG5-00/3.1.4 ACTION: NAW] To ensure that JHT (AF2 Project Scientist) is made aware of this request to contact the AAO. 3.1.5 The WYFFOS spectrograph upgrade project is underway. Preliminary optical design is being carried out by Richard Bingham (OSL/UCL) with the aim of optimising WYFFOS for use with a larger (4kx4k) optical CCD array and possibly extending it's use for operation in the near-IR at J+H. Preliminary indications [report received from Bingham 25 Apr 2000] are that it will be possible to adapt WYFFOS to have an external focus with a 4kx4k optical camera. However, extension to the near-IR would be problematic, the original optical design of WYFFOS was for less than 1um. Image quality is poor in the near-IR. [IWG5-00/3.1.5 ACTION: NAW] Distribute to IWG the science and technical inputs upon which Richard Bingham has based his preliminary WYFFOS design work. 3.1.6 Longer term upgrades involve the manufacture of new fibre modules containing a number of deployable IFUs and single small fibres to feed the upgraded WYFFOS (upto 1200 fibre elements in the optical). The IWG was concerned that full science drivers should be in place to define the longer term development of AF2/WYFFOS. [IWG5-00/3.1.6 ACTION: NAW] Develop science requirements document for AF2/WYFFOS as a basis for decision making on future development in this area (especially for dIFUs and near-IR AF2 fibres). 3.1.7 The IWG noted that major engineering effort would be needed to speed up the rate at which AF2 could configure the field. Likewise, implementing the ability to cross fibres, would require tensioning of the fibres (as with 2dF). 3.1.8 One possible development envisages providing a 2kx2k MCT HAWAII-2 array as the detector for an IR-WYFFOS. This device could also be used with NAOMI. However, this would require a full funding proposal, the devices currently cost in excess of $ 0.5M. 3.2 The present major area of instrumentation development at the WHT focuses on exploitation of the AO images that will be provided by the NAOMI system. 3.2.1 Near term developments include the NAOMI+TEIFU+WYFFOS combination giving IF Spectroscopy at high spatial resolutions. RMS gave a brief overview (view graphs) of the TEIFU instrument. 3.2.2 TEIFU is optimised for the 500-1000nm range. It consists of two units of 504 fibre elements, each of which can be individually deployed in the 70 arcsec NAOMI FOV. The fibres feed the WYFFOS spectrograph. The spatial scale is 0.25 arcsec per fibre. 3.2.3 RMS reported that TEIFU had suffered from lower than expected throughput on its first commissioning run. A large part of this was due to losses in the WHT's Nasymth de-rotator - this has since been re-coated. The latest TEIFU run shows better through-puts. RMS suggested that coating TEIFU's fore-optics would gain a further 10% in throughput. 3.2.4 The IWG AGREED that the necessary changes to the TEIFU fore-optics should be implemented to allow it to be used with NAOMI. RMS indicated that Durham should be in a position to commission TEIFU with NAOMI Q1 2001. He anticipated that TEIFU would operate in a de-scoped fashion, with only the option of deploying the two 504 bundles as a 1008 element single IFU. 3.2.5 RMS stated that, with a change of fore-optics, TEIFU could be upgraded to allow operation in the near-IR J and H bands. Optimum sampling would be 0.15 arcsec/fibre, with a fixed contiguous format of 5x5 arcsec. 3.2.6 The main difficulty would be in the provision of the near-IR spectrograph. Options could be: - IR-TEIFU + INGRID: here INGRID would need to be upgraded with a grism/VPH dispersive element and a pupil re-imager. Because of the small 1kx1k detector the TEIFU input slit would need to be ordered into 3-4 parallel slits. - IR-TEIFU + IR-WYFFOS: initial indications are that the optical performance of WYFFOS beyond 1um is poor and that this option would require a major redesign of WYFFOS - IR-TEIFU + LIRIS: this IAC spectrograph has been designed for use at the Cass focus of WHT. The (now fixed) design does not include the facility of an AO feed. However (email from SAM) an add on feed could be investigated. [IWG5-00/3.2.6 ACTION: NAW/RMS/SAM] Investigate further the options for funding the necessary upgrade to produce IR-TEIFU and the associated IR spectrograph. Consider science drivers for resolution, use, etc. 3.3 NAW highlighted a number of mid term developments resulting from the Oct 1999 Instrumental Announcement of Opportunity. 3.3.1 A full OASIS bid for funding requesting Dfl 720K was submitted to the NL NWO (PI: van der Hulst). This proposal seeks to bring OASIS to the WHT for use with NAOMI. The project includes the adaptation of OASIS to fit with NAOMI, and also a number of improvements to OASIS to improve its system efficiency. The referees reports were very favorable, a decision on funding is expected mid June 2000. If it is successful OASIS will be commissioned on the WHT in March 2002. 3.3.2 The Coronograph proposal (PI: Doel) was supported by the INGB. Subsequently a fuller case for funding was submitted to the Jan 2000 AC PPARC committee who recommend funding this at the UKP 120k level. The project is currently in the design stage, commissioning is foreseen for Q3/4 2001 with NAOMI. The Coronograph will feed INGRID, TEIFU and OASIS. 3.3.3 PD presented a brief summary (view graphs) of the Coronograph unit. When working in the optical the coronograph could take advantage of the re-design of the NAOMI optical science port proposed as part of the OASIS bid. This envisages that one port provides both an IR and Optical science feeds. Multiple dichroics are employed to enable a user selection of the science light - the unwanted light being feed to the wavefront sensor. The design is based on one successfully implemented at the CFHT with its AOB. PD noted that if the OASIS bid, and hence the optical port re-build, were not funded, then it would be possible to implement a somewhat less elegant optical pickoff. This would add to the project cost and is being included as a contingency for planning purposes. Final designs of the coronograph are occurring in July/August 2000, thus after the OASIS bid outcome is known. PD stated that the coronograph would provide a powerful capability when coupled with NAOMI. With TEIFU and/or IR-TEIFU, integral field AO coronographic spectroscopy would be a unique capability, surpassing the capability of HST. 3.3.4 PD noted that the present design for the Coronograph has a FOV of 10 arcsec. The IWG considered that this would be acceptable for coronographic imaging applications. [IWG5-00/3.3.4 ACTION: IWG] To confirm that the 10 arcsec FOV is acceptable for the Coronograph. 3.4 The implementation of a Laser Guide star on NAOMI and it's impact on the prioritisation of AO instrumentation options was discussed. 3.4.1 Chris Dainty provided an overview (view graphs) of recent site characterisation studies of the La Palma and the recently submitted (May 2000) JIF bid to fund a Na LGS system at the WHT. If funded the LGS system would be available for use on the WHT by end 2003. [IWG5-00/3.4.1 ACTION: CD] Chris Dainty to distribute copies of the JIF bid to the IWG members and all persons who had written in support of the bid. 3.4.2 CD noted that the recent campaigns to measure the Na layer characteristics above La Palma had produced excellent results. The low power Na laser, when viewed by a combination of a nearby Meade telescope, the JKT and WHT, had enabled the height and amount of the Na layer to be measured. Runs at various times through the year, showed large variations in the amount of Na. This had driven the lower limit to the power of the Na laser that would be needed for the laser beacon. 3.4.3 A proposal for a Laser Guide Star system to work in conjunction with NAOMI on the WHT had been submitted to the 3rd JIF round by Dainty. This was a joint ICST/Durham/UCL proposal, having a value of UKP 3.9M. A high level of support from a broad cross section of the UK astronomical community had written in support of this bid. 3.4.4 The LGS system, based on a powerful 20W Nd:YAG Na laser beacon (c.f. 3W laser in the ALFA system) would always be sufficient to excite the Na layer and provide a bright artificial guide star for NAOMI. It would enable significantly enhanced sky coverage, and ensure that the NAOMI AO system would be able to provide image resolution improvements to most astrophysical targets. 3.4.5 The IWG AGREED that the proposed LGS was of the utmost importance. They noted that this system could be available on the WHT several years before MCAO systems on Gemini or the VLT. NAOMI+LGS+the new AO instrumentation under construction or in the planning stages, would ensure that the WHT had a competitive edge, even measured against Gemini. 3.4.6 The IWG AGREED that the next IWG should further discuss the LGS system and implications for AO instrumentation. Further they should consider possible routes to implement the LGS system in the case that the JIF bid was not successful. Input into a possible bid to PPARC or other funding agencies/sources would be required. UPDATE ON NEW INSTRUMENTATION PROPOSALS 4. NAW gave an update on the new instrument proposals that had been supported by the IWG and subsequently the INGB (at its Dec 1999 meeting): 4.1 The Coronograph for NAOMI: as discussed in 3.3.2, PPARC have recently approved funding for this instrument, with commissioning expected Q3/4 20001. 4.2 OASIS for NAOMI: as discussed in 3.3.1 a full bid to NL NWO for funds to bring OASIS to the WHT has been submitted. The outcome is expected June 2000. 4.3 Mosaic: PPARC have approved design funds at the UKP 25K level. 4.3.1 RMS presented a brief update (view graphs) on MOSAIC. The design funds will be used to develop a preliminary design for MOSAIC based on a well developed science drivers. Further simulations of the atmosphere above the WHT will be made. The mechanical layout and optical designs of the instrument will be updated. A fuller budget estimate and project time-line will be prepared in preparation for a full funding submission. 4.3.2 RMS indicated that the Durham group have a tender action under way to acquire the Rayleigh laser beacon (as part of their existing rolling grant programme). They aim to test fire this with a mono-static launch through the WHT in Feb 2001. June 2001 will see the Rayleigh beacon tested in conjunction with the ELECTRA AO system to measure off-axis performance 4.3.3 The IWG were pleased to note the rapid progress that was being made with this instrument, and were especially interested in the Rayleigh laser beacon tests planned for early 2001. NAW reported that the MOSAIC concept had been presented at the recent (Mar 2000) SPIE conference in Munich on Astronomical Instrumentation. 4.3.4 RMS commented that MOSAIC would perform optimally on those ~25% of nights when the predominate turbulence was due to the low level layer. The IWG AGREED that flexible scheduling would be essential for MOSAIC, and indeed for all AO instrumentation planned for the WHT. It would be essential that the correct programmes were carried out dependent on atmospheric conditions. RMS further noted that the best conditions for MOSAIC were not necessarily the best for NAOMI. 4.3.5 CD commented that his group are developing a version of SIDAR which could be in continuous operation and give real time descriptions of the atmospheric turbulence profile during the night. The IWG requested to be kept informed of developments with this, and recognised that such a device would be very useful for real time site characterisation for use in planning the observing programme/instrument mix at any particular time. 4.4 F-Ps for NAOMI: this proposal was deferred. ANY OTHER BUSINESS 11. Any Other Business was discussed. 11.1 The date of the next meeting is to be arranged. However it should be before the next INGB meeting that will occur end Oct/ begin Nov 2000. Thus it is probable that the next IWG should be begin Oct 2000. [IWG5-00/11.1 ACTION: NAW/RGM] Confirm and advise date of next IWG meeting. 11.2 RGM and NAW thanked Chris Dainty, Peter Doel and Ray Sharples for attending the meeting. Nicholas A Walton 21 Oct 2000 (IWG secretary) (orig) 23 May 2000