Top End

Andy Adamson

Head of UKIRT Operations/Director of Science

Flexible scheduling

The switch to flexible scheduling has by now affected virtually everyone connected with UKIRT. The software group who largely enabled the switch are continuing to enhance the system; engineering and technical staff now have to maintain the whole instrument suite continually because observations with any of them may be carried out at any time; support scientists have had to adapt to a whole new set of requirements when training visiting observers; and finally of course a raft of new responsibilities have fallen upon the observers and P.I.s themselves. Observers now have to be willing to take on observations well outside their normal areas of expertise, using instruments which may be quite new to them, and P.I.s have to ensure, in conjunction with close vetting by UKIRT staff, that their programmes are straightforward to execute and documented well enough that this is possible.

Flexing naturally creates some interesting combinations of observers and programmes, as two examples from 03B will illustrate. First, a Cataclysmic Binary observer has successfully taken data on brown dwarfs, dust in quasars, UL X-ray sources in galaxies, massive YSO candidates and the host galaxies of powerful radio sources. Secondly the observer on a high-redshift QSO project has, besides their own programme, contributed data to programmes on cluster lenses, jets and outflows from massive YSOs, disks in young low-mass stars in Orion, etc.

Of course (as Thor points out in his column) it has not all been plain sailing, and we are learning how to fully specify observations to maximize the efficiency of the operation. But as we show in the article in this issue, the early success of this endeavour as reported in the last newsletter appears to be fundamental and was sustained through the semester, and with 03A behind us the feedback from P.I.s whose data were obtained for them has been good. The science returns of this observing mode are clear, and there is no going back: for PATT-allocated time UKIRT will remain flexibly scheduled from now on, and this will also apply to operations with WFCAM. One shortcoming was clearly identified from our experience with semester 03A: the feedback loop between JAC and remote P.I.s was not closed as quickly or as automatically as would have been ideal. Thanks to some excellent software work over the summer, both UKIRT and the JCMT now offer on-line access to graphical representations of the reduced data products for a given programme. This will enable remote P.I.s to quickly inspect and comment upon the data quality without downloading data sets and reducing them. One caveat: our disk space is limited, so make sure you check in quickly once you've been informed that data are available!

Quietly, without fanfare (and with gratifyingly zero complaint from observers), a relic of bygone observing has been pensioned off. No, I am not resigning; UKIRT simply no longer provides paper log-sheets. Their replacement - the OMP Observation Log - keeps track of all observations, and allows for entry of notes and comments at various levels, including attaching comments to individual frames (which can be flagged for quality at the same time), and entering generic notes on the weather conditions and progress of the night. This will provide a genuine archive of useful observing information to complement the wealth of detail already present in UKIRT's FITS headers.

Aluminising

The summer of 2003 was a testing one, for the JAC engineering staff at least; aluminising the primary was combined with contract re-engineering the primary lifting plug to support WFCAM, the wide-field imager slated for delivery early in 2004. As the saying goes: heaven forbid that the inevitable should happen... A thoroughly well-devised aluminising and engineering plan was being carried out flawlessly when a JCMT secondary mirror fault was compounded by the splitting of the JCMT's protective fabric membrane. Our thanks to the ETS group for working through all this, and for getting UKIRT back on sky in time for the onset of semester 03B. The first night of "functional checkout" post-aluminising was (perhaps disappointingly) uneventful; a wavefront sensing run was done in order to adjust the primary figure after the mirror's trips across the summit and reassembly of the telescope. Hopes of a neat "before and after" comparison were dashed when we turned UIST onto a standard star in advance of the wavefront sensing, and got half arcsecond image quality without adjusting anything! The new primary coating looks superb and we expect to capitalise on the consequent reduction in emissivity and increased throughput in Semester 03B.