ATCA Release notes for 2024OCT
BIGCAT installation: At schedule release, it is anticipated that BIGCAT installation and commissioning will commence sometime this semester. We will therefore be continuing our practice of releasing the schedule in stages. BIGCAT installation may commence as early as November, and so the first release of this schedule only covered the first 6 weeks of the semester. The entire semester has been scheduled to determine what time is likely to be available for all projects, and we have been able to schedule all projects with a TAC grade of 3.4 or higher. The second release covers the time until the end of the maintenance week on December 13.
If BIGCAT installation is delayed past December, then we will release another version of the schedule no later than November 15.
ATCA observing: ATCA observations may be conducted by trained observers at any location, including the Paul Wild Observatory, the Marsfield Science Operations Centre (SOC) or remotely.
To book on-site accommodation at either the observatory or Marsfield lodge, or just to register that you plan on observing at the SOC without requiring accommodation, please visit our online booking system, and make your booking at least two weeks in advance.
First-time observers are required to undergo a basic online training program, to learn the fundamentals of observing with the ATCA. Observers with prior experience are also welcome to participate in this training program.
This semester, we continue with our new support system where each project has their own Observing Expert who can provide support before, during and after observations.
To learn more about our basic training and the Observing Expert model, please visit the ATNF support page.
Observing experts (OEs) for each project this semester will be contacted by the observatory on or before March 15. Each OE will be informed of their duties and responsibilities for their project, and given instructions for how to perform their role.
Registration to observe, or to undergo training, or to book accommodation will require you to have an ATNF UNIX account. If you need to obtain an account, please use the online request form. Please note that it may take several business days to process this request, so please make your request well in advance of your training or observing.
CABB modes: Only the following CABB modes will be available for the 2024OCT semester:
- the 1MHz continuum ("no zooms") mode,
- the 1MHz zooms mode (1M-0.5k), with up to 16 zoom bands per IF available,
- the 64MHz mode (64M-32k), which provides 32 channels of 64MHz bandwidth and up to 16 zoom bands (each having 2048 channels across it) in each IF
- the "hybrid" mode, with 2048 x 1MHz channels in IF1 (and no zooms) and 32 x 64MHz channels in IF2 (with zooms), and
- the VLBI tied-array mode.
See the CABB webpage for more details. CABB mode changes are mostly routine, except for changes to the 1MHz zoom mode, 64 MHz zoom mode, and hybrid mode, which require approximately one hour: this mode change is done by local staff or suitably trained others. In the graphical version of the schedule the requested CABB mode is shown in the top right corner of each block.
The 64 MHz and 1 MHz zooms modes are degraded due to bad blocks in both IFs. In IF1, blocks 3, 12 and 15 do not correctly form zooms, and in IF2 blocks 22, 23, 25 and 29 are also faulty. These faults mean that 3 zooms in IF1 and 4 zooms in IF2 cannot be trusted to provide useful data. Unfortunately it is not possible before testing to know which of your scheduled zooms might use these blocks, and so if you plan on using zooms this semester, please reach out to your observing expert well in advance, and/or to observatory staff.
Blocks 3 and 25 are always faulty in the pulsar binning mode also, but because they create large blocks of faulty channels in the continuum bands, the pulsar binning mode is no longer offered.
ATCA portal: The portal is a web-based tool that enables the observers to book in advance for observing blocks and to register as the current observer-in-charge. It also provides alerts, contact details, and a improved chat facility over that previously used in the ATCA observing VNC session. More details are available from the ATCA Users Guide. First-time users should refer to the ATCA Portal Beginners Guide.
Radio Frequency Interference (RFI): There is a strong emitter in the 16cm band in the 2630-2670 MHz range, a previously relatively clear part of the spectrum often used by 16cm-band observers for their delay calibration. Instructions for dealing with this are are available from the ATCA Current Issues webpage. RFI in the 16cm band also causes the sampler statistics to fluctuate, and the automatic attenuator setting often does not work. A set of standard attenuator settings for the 16cm band has been determined and these can be manually set -- see section 3.2.2 of the ATCA User Guide for more details. (If they have been set by a previous observer, it may not be necessary to set them again.)
There is also some RFI in the 15mm band in the frequency ranges 17.7--18.2 GHz, 18.8--19.3 GHz and 19.7--20.2 GHz which arises from a geostationary satellite and is stronger towards equatorial declinations. See the ATCA Current Issues webpage for more information.
RFI in the 16cm band cannot yet be mitigated on-line, but a mode in the correlator allows observers to more easily mask its effect on the diagnostic visibilities, using median averaging. Instructions on how to do this can be found from the ATCA Current Issues webpage.
NAPA Proposals: A number of NAPA (Non A Priori Assignable) proposals have been submitted for ATCA in 2024OCT. We have a policy for dealing with NAPA over-rides, intended to ensure highly time-critical projects can be scheduled on the telescope. For the 2024OCT semester, any NAPA which received a grade equal to or higher than the grade at which most of the projects got most of their time, will be able to over-ride any scheduled project. For this semester, all twenty-five NAPA projects meet this criteria.
If triggered, observatory staff will discuss with the proposers the best time for the over-ride to occur, which may not necessarily involve any project being displaced. Requests to trigger a NAPA proposal can be made by emailing the ATNF alert group, as described here.
Any observations displaced by a NAPA will be rescheduled if possible, but this is not guaranteed.
There are two NAPA projects that are authorised to use the rapid response service. Rapid response over-rides may occur at any time without staff or observer intervention.
Investigators triggering NAPAs are reminded that claim staking is not permitted under ATNF policy.
In order to minimise the impact of multiple competing triggers to observe the same event, the TAC has recommended that we encourage data sharing between NAPA teams who nominate to observe the same coordinates with the same receiver configuration and observing strategy. Observatory staff will discuss this arrangement with the affected teams should this situation arise.
Green Time: Green time should be requested through the Portal. Instructions for doing this can be found in the "Book" tab in the Portal. Requests for green time can be made at any time during the semester, but the final allocation will not be made until 1 week beforehand.
Please also email the ATNF alert list (
Only projects explicitly approved and that appear in the Portal schedule may be observed on the telescope. Under no circumstances can the telescope be used without prior permission from the Directors or the scheduler.
Daylight Saving: Daylight saving in New South Wales will start at 2:00am (AEST) on Sunday, 6th October 2024, when clocks will be put forward one hour. AEDT is 11 hours ahead of UTC. Daylight saving in New South Wales will end again at 3:00am (AEDT) on the first Sunday in April 2025.
Public Holidays:
- Labour Day (NSW) Monday Oct 7 2024
- Christmas Day (Aus) Wednesday Dec 25 2024
- Boxing Day (Aus) Thursday Dec 26 2024
- New Year's Day (Aus) Wednesday Jan 1 2025
- Australia Day (Aus) Monday Jan 27 2025
Version history:
Version 1 of the schedule was released on 2024 September 2.
Version 2 of the schedule was released on 2024 September 30.
Generated: Jamie Stevens (30-sep-2024)