Observing Run Synopses

Commissioning run: 16-19 July 2001 (2+2)

This run was postponed from 5-6,16-18 April 2001 because of delays in instrument delivery.

Although there were some minor equipment problems, overall the PN.S turned out to run quite smoothly and according to expectations. The measured telescope-to-detector efficiency of 33.3%±1.0% was in accord with the expected 35.0% (see here for the derivation).

The weather was less cooperative: dust, clouds, poor seeing. We ended up with relatively little high-quality data. An overview of the targets observed and data quality can be found here.

Photos from the run can be found here and science images here.

Run #2: 13-18 September 2001 (3+3)

The observing conditions were mostly good, and the instrument performed well. We observed several galaxies, getting especially good data on NGC 821, NGC 7332, and NGC 7457.

Photos from the run can be found here and science images here.

Run #3: 7-14 March 2002 (4+4)

Poor observing conditions (poor seeing, cloud cover, ice storm, etc.) meant that we got effectively one night of good data in eight nights' observing. Much better than nothing! We got about a half night of data on each of NGC 3379 and NGC 4494. Photos from the run can be found here and science images here.

Run #4: 8-13 October 2002 (3+3)

M31 run, Dave Carter, Helen Merrett, AJR, NGD and (first three nights) KK. HM/NGD/AJR had an overnight stop in Madrid, KK a day later.
We convinced the observatory to allow us to try out the MARCONI2 detector on the right arm. This did not improve the high read-noise and cross-talk, which fact led to a thorugh investigation of the problem (which was also present when the detector was replaced by the EEV13). The technical team managed to get acceptable read-noise, but on the third day there was a breakthrough when the culprit was identified (controller power supply). We subsequently marked the preferred power supplies for future use.
Mixed weather for 8/10 and 9/10 with the dome at times closed due to rampant humidity - the seeing was also quite poor. During 10-13/10 the weather was good with low and stable cloud patterns and the seeing steadily improved. However on the last three days approximately one hour per night was spent on a GRB override.
Some 130 (?) fields were observed with a standard exposure of 900s, the results are promising.
Photos from the run can be found here.

Run #5: 28 February - 7 March 2003 (4+4)

Primary programme. EEV12+Marconi2 requested. Marconi2 is cosmetically better and has slightly higher QE. Observers AJR, HM, NGD and NN.

AJR, HM and NGD arrived early in order to investigate "clunk", suspicion is that the grating unit might be subject to occasional bimodal disalignment. On Feb 27 we dismantled it and convined ourselves that the pushers which press the grating against the mid-line might be too weak, allowing lateral movement and maybe rotation within the available space (some mm) - see, however, John Hart's email of 1/3/03. Trial: K. Dee added a second spring, and we inserted a sawn-off M4 nylon screw head into the hole, further increasing the pressure. Blew dust off. Possible resulting changes in grating alignment indicated by PNSGANG=26.6-2 in headers.

We experienced great difficulty in getting Marconi2 focussed (right arm) and optimum result was 3.0 (c.f. 2.5 for EEVs). Currently not understood. Gives rise to different optimum telescope focus on L/R arms. During first night the network went down, causing some difficulties with target optimalisation. However no technical problems otherwise and good data obtained. Confirmed that Marconi2 is some 10% higher in QE, though thicker and thus more prone to cosmic ray events.

On days 2 through 6 we likewise stuggled with focus, investigating possible culprits (tilted filter, the modifications to the filter unit). Cameras not parfocal, as indicated by telescope focus runs. TCS failed at the very end of night 2, sky flats were made with WHT at zenith. Night 3 had seeing of ~3".

Night 4, reverted to EEV13 on right arm. Seeing was again ~2-3".

Night 5 thru 8 had clouds off and on but reasonable seeing.

Summary:
NightHoursSeeing1" HoursGalaxies
1 (28 Feb)6.51.5"2.8N3379, N4339, N4494
2 (1 Mar)7.51.5"3.4N2549, N3379, N4339, N4494
3 (2 Mar)6.252.6"0.9N3384, N4494
4 (3 Mar)5.72.3"1.1N3384, N3377, N4494
5 (4 Mar)7.51.3"4.2N2549, N3379, N4339, N4494
6 (5 Mar)5.11.2"3.7N2549, N3379, N4374
7 (6 Mar)0.91.2"0.6(N2549), (N3115), N4374
8 (7 Mar)0.00.0(N3379), (N2549), (N4374), (N3384)
All39.51.5"16.7

Official dark time lost: 16.5h / 78.0h

Photos from the run can be found here.

JKT-imaging-Run #1: 1-5 June 2003 (5NL)

Mirela Obric, PhD student at Kapteyn, obtained photometric-quality images of NGC7013 and NGC5866 with the Harris-R filter (6373/1491) for use in our modelling of these S0 galaxies.

INT-wfc-Run #1: 16-21 August 2003 (6NL)

M31 survey run using the wide-field-camera at INT. Obsevers Dave Carter and HM.

Good seeing on 4 nights (av 1.2"), cloud cover for 1 night. 23 fields imaged in M31's halo.

Run #6: 29 Sept - 5 Oct 2003 (4UK+3NL)

M31 survey extension - major axis, stream and northern spur. Observers HM, AR, NN, DC.

3.5 clear nights. Varied seeing (1.0-2.0"). 88 fields observed.

Run #7: 12- 21 april 2004 (6UK+4NL) (P39 Mer + N12 Dou)






last modified by HM, 12 January 2004