Night Reports 2005

November 2005
Hours spent Observing: 140.0, Weather: 147.3, Technical downtime: 18.4

Reliability and Downtime: Observing and poor weather have been balanced about 50:50 which is disappointing, but it is Winter. Technical downtime has again fallen to 10% after the small increase in the preceding month. We are very pleased with this consistent performance since the mid Summer.

Tropical Storm Delta hit the Canaries at the end of the month causing a lot of damage, very little of which was at the observatory. Our anemometer does not read above 65mph, but the NOT weather station appears to have registered winds exceeding 90mph. Damage to LT included the loss of a sign and a small external out-house, loosening of the weather station rain gauge and damp inside the webcam, so nothing which prevented observations once the weather cleared.

Engineering: There have been three visits to site since the last report. One was predominantly electrical and IT related, working on increasing system robustness and replacing failed hard drives.

The second included TTL engineers and mostly involved software upgrades. The full software infrastructure of high and low-level software (excluding just the TCS) has been updated to the latest TTL release versions. It has been over a year since the last upgrade. Despite a small problem with the focus mechanism which is fully resolved, no observational time was lost due to the software change which was performed in a staged manner over several days. Some minimal work was also possible to investigate the optical astigmatism and the results of that work are still under analysis.

The third visit was for instrument commissioning. Two new instruments, the RINGO polarimeter and the Meaburn Spectrograph have seen first light and are currently undergoing robotic commissioning to allow their routine use. Neither are common user instruments, but further details can be found in a news item on the LT web pages. The bad news on the instrumentation front is the damage to the cryogenic system for SupIRCam. We have already directly contacted all users of this instrument with further details of the problem.

Queen's Anniversary Prize: It has been announced that the work of the ARI, including the Liverpool Telescope has led to Liverpool John Moores University being awarded the biennial Queen's Anniversary Prize for Higher and Further Education, one of the UK's most prestigious educational awards. Further details can be found in a news item on the LT web pages.

October 2005
Hours spent Observing: 126.4, Weather: 141.3, Technical downtime: 39.4

September 2005
Hours spent Observing: 63.8, Weather: 66.9, Technical downtime: 1.3

Reliabilty and Downtime: A significant amount of time was lost this month as a consequence of the brush fires on La Palma (this is noted as "Weather" in the statistics). We would like to thank all the employees of the ORM and staff from several other telescopes whose efforts saved the observatory site facilities from serious damage. From the numbers above, you will see that excluding the scheduled maintenance, the telescope downtime resulting from technical faults has again been very low this month.

Engineering: The September engineering trip went very well with almost everything we had hoped for being completed. The mirror was recoated and new zero points will be published soon on the RATCam information web page. A first look reduction shows a 0.3 mag increase in SDSS r' throughput. Work on the cassegrain rotator appears to have significantly improved its performance, which should in turn bring pointing and tracking improvements. The optics have been recollimated better than they were before the engineering work and investigations are ongoing to see if work on the secondary mechanism has had any effect, beneficial or detrimental on the focussing. A new pointing model has been installed with an RMS pointing error of about 8 arcsec. For the first two weeks of October, a small fraction of each night will be spent on further engineering and performance tests, but the telescope is effectively back in full science operations.

Imager Field Rotation: The most pleasing outcome of the downtime is that the cassegrain de-rotator cable wrap has been reorganised in such a way as to allow a full 360 degree travel. Users can now specify the field rotation they would like for each observation. For all targets currently loaded in the phase II database, a default orientation of 'sky position angle = 0' has been assumed. If you require a field orientation other than this, please contact the support astronomer, Chris Moss, just as you would to make any modification to your observing strategy.

Support: Until now, users have been only been able to access their data through the "Recent Data" pages. You can now download your data from the archive search results screen. You will still need to input your proposal ID and password.

Time Applications: Applications for PATT semester 2006A have closed. For semester 2006A, the PATT oversubscription rate for available time was 3.8. Following a release of engineering time to supplement the available PATT time, the oversubscription rate was readjusted to 1.8 (324.5 hours requested for a total of 180.8 hours available for the semester; in addition, 235.2 hours have been pre-allocated to the semester from PATT proposals in previous semesters.) Calls are expected to be made soon for the JMU TAG and ITP international time. Announcements will be made on the News web page.
 

August 2005
Hours spent Observing: 173.3, Weather: 63.4, Technical downtime: 13.1

First I would like to thank all those who contributed science results to the recent telescope operations report for PPARC. It was good to see so many interesting results starting to come from the telescope. Equally we thank those who gave feedback about the telescope performance limitations which had prevented you yet producing any results from the LT. All these comments and suggestions have been discussed and we have been able to respond positively to many of you.

Reliability: The most obvious headline this month has to be the extremely encouraging increase in telescope reliability. This has certainly been our best month yet with only 5% technical downtime and only one full night being lost. The weather has been a little disappointing for August.

If you read the nightly reports, you will see a variety of small one-off problems which have been fixed as the come up. The only two re-occurring problems to have lost us time this month have been the mysterious network losses to the various nodes and initialisation errors of the focus mechanism. The latter has been fully resolved in software. The former is still under investigation.

Performance: Those receiving data will know that there continues to be work to be done on the tracking performance of the telescope, however significant improvements have been made since the last report. Following the re-alignment of the Azimuth encoder system at the end of June, the fraction of severely trailed images has dropped from 10% to 2%. There will be an extended period of engineering down-time in September which is to include installation of the new auto-guider to help address the tracking limitations.

We are now also using a new pointing model which was derived following the encoder realignment. Pointing repeatability within a night is better than 10 arcsec RMS and absolute accuracy from night to night adds a further 10 arcsec RMS error.

Support: There have been further minor changes in the data archive and MyLT web pages. Both have been made more robust and the "Recent Data" pages at Recent Data have been subdivided by proposal ID. We hope this makes it easier for you to quickly locate your data.

The application guidelines have been fully revised for PATT semester 06A. Please take a look before submitting your application.

There are still a few programmes which have been allocated time in semester 2005B for which we have not received phase 2 observation specification forms. As soon as we get these forms, the data can be loaded to the database and be ready for observation. Of course, if you have target-of-opportunity time, you obviously cannot submit forms early.

July 2005
Hours spent Observing: 131.1, Weather: 51.9, Technical downtime: 40.4

June 2005
Hours spent Observing: 108.3, Weather: 8.8, Technical downtime: 97.3

Another mixed month in terms of hours observed. The first half of the month was very good, but a lot of time has been lost in the second half of the month to the failure of the mirror cover to open. This has now been fixed. Whilst on the subject of telescope problems, users should note that several times this month the telescope was going in and out of focus during the night. The badly defocussed data has not been distributed to users.

Engineering: The promised site visit by a joint TTL / ARI team has taken place. A full review of the performance of the hydraulic system was performed, but it is too early to say if there will be any major changes in telescope performance. Some work was also done on the Azimuth encoders which has made a very significant improvement the telescope tracking.

Support: Dr. Chris Moss has been making contact with many observers and discussion with them has started to increase observing efficiency for several programmes through increasing our understanding of user requirements. In more tangible changes, there have been some modifications to the data archive. Most of these will not be obvious to the user, but there have been a few formatting changes to the archive search tools (Data Archive). Most significantly, the new data subdirectories available at Recent Data are now arranged to put all the data from a given night together rather than the previous practice of filing them according to UT date which led to each night's data getting split across two subdirectories.

Email Contact: Finally, we wanted to make sure everyone was aware that emails get sent to project PIs to notify them as soon as any data has been obtained and are available in the archive. Several PIs have not been receiving these emails due to the configuration of firewalls and email SPAM filters. If you know that data have been obtained for your programme, but you have not had an email about them, please let us know so that we can monitor the extent of this problem. You can always check the new data page (Recent Data) or MyLiverpoolTelescope to see if you have any new data available.

May 2005
Hours spent Observing: 124.4, Weather: 27.2, Technical downtime: 79.2

Science: We have had a real science highlight this month, with our best yet fully automated GRB response. The LT obtained multi-colour photometry of GRB050502 starting 3 minutes after the Integral gamma-ray detection. See the news story on the LT News page or in the news archive.

Engineering: Telescope reliabilty is up again this month after a disappointing April. Following my upbeat comments in the April report, the first week of May proved very poor. The two main problems were a sticky Cass bearing and a hydraulic pump motor failure. The latter was replaced and has not given us any further problems. Since this is the second pump replaced this year (see Jan 2005), a full recheck of the hydraulic scavenge system has been scheduled for June. The cass bearing problems are currently more mysterious and TTL will be helping us investigate this also in June. In the meantime, we have a work-around which has kept us observing most of the month.
We spent a couple of nights on a more thorough analysis of the pointing performance. The great majority of pointings are currently within 30arcsec of the field centre, though there still occaissional unexplained errors up to 2 arcmin.

Support: It has become clear that the differences between the way the LT and traditional observatories operate has caused a significant stumbling block for many observers preventing optimum exploitation of the telescope. This month, Dr Chris Moss has joined the LT operations group as our new support astronomer. He will not be involved in any routine maintenance and operations, allowing him to concentrate on helping all users obtain the maximum scientific returns from their observing time. He will be overseeing and providing expert advice throughout the application, scheduling and observing process. Revisions to the submission procedures will be announced soon, but in the mean time he can be contacted via the LT Helpdesk at this address (updated 5th Nov 2007).

Other: The Live Data page has been made public online. You can check on the LT weather station and the state of various telescope mechanisms at any time. On moonlit nights you can even see the telescope moving on the webcam.

April 2005
Hours spent Observing: 78.7, Weather: 73.2, Technical downtime: 93.4

Engineering: The first half of the night was blighted by degrading Azimuth bearing oil flow performance. A site visit was therefore scheduled for mid-month. Following the work on 20/05/05, no further time has been lost and the telescope has performed reliably for the last week of the month.

March 2005
Hours spent Observing: 121, Weather: 132, Technical downtime: 38.
First half of month spent under the tail end of the blizzards that prevented observing during February. Observations were back underway around mid-March.

February 2005
Time used (Observing:Weather:Fault) 0 : 283.9 : 0

Weather: Incredible as it may seem, we have not opened the enclosure once in February, entirely due to weather. We do not yet have archival LT weather data on-line, but you can see how bad it has been from the ING weather station. For two weeks of the month, the telescope was not contactable due to a circuit breaker supplying the IT equipment tripping and it being impossible to gain access to site to reset it. Two LT staff made an emergency visit to help Dirk with the anticipated clean-up. In fact things were not as bad as feared though there is still significant water ingress to the enclosure during high winds. The new top-seal guttering has made a great difference. The telescope has been started up and run under local supervision. We expect it to be available as soon as the weather clears and ice melts. The autoguider has also been returned to Birkenhead and TTL are working on fixing the problems we have had. Of course none of the work done during the January maintenance visit has yet been properly tested on-sky.

Automation: On the automation front, general system robustness testing has continued despite being unable to observe and we have removed the restriction which stopped the telescope re-opening during the night after any technical fault (see Dec. 2004 report). This means that any minor problems which can be fixed by the automated fault recovery routines will no longer lead to the loss of the rest of the night.

Science: In science/data matters, the downtime has not been wasted. We have taken the opportunity to finally put on-line the new web pages (https://telescope.ljmu.ac.uk/), the searchable data archive and phase-II database access under the catchy title "My Liverpool Telescope".

January 2005
Time used (Observing:Weather:Fault) 93.7 : 133.4 : 102.5
This month we had a "IT & mechanical servicing mission" with two staff from ARI joining Dirk on-site for a week. During their visit they installed a variety of new IT equipment, installed new webcams (accessable from this web site), made a long-term fix to the enclosure locks (see Dec. 2004 report) and portal guide rollers, investigated oil flow limit problems (see 11-13/01/05) and ran further tests on ongoing autoguider problems (we now think the chip is not salvageable). Most of the above were resolved successfully and we are anticipating an increased system robustness over the next couple of months. Weather has been terrible as you can see.

On the automation side, we obtained twilight flat-fields using the fully automated routines for the first time. This will hopefully be integrated into the daily autonomous operations in the coming month.