ATNF Telescope Status for 2015OCT
All ATNF Telescope Applications for 2015OCT must be submitted using OPAL.
Cover sheets from previous semesters should be re-loaded into the cover sheets editor and carefully re-checked before (re-)submitting a proposal.
The deadline for all proposals is 07:00 UT (17:00 Sydney local time), Wednesday, 17 June 2015 .
For 2015OCT, ATNF proposals will be accepted for the:
- Australia Telescope Compact Array;
- Parkes 64m telescope;
- Tidbinbilla 70-m (DSS-43) and 34-m (DSS-34) antennas; and
- Long Baseline Array.
What's new in 2015OCT?
- Observing support and remote observing qualification have recently been reviewed and a new ATNF observing support model is now in place.
- ATCA: Default observing location is now the Science Operations Centre in Marsfield, Sydney
- Parkes: The 20-cm multi-beam receiver will be removed from the focus cabin for an extended period early in the 2015OCT semester. Some 20cm capability will be made available in its place.
- Parkes: Issues with the reliability of DFB3 remain unresolved: at present DFB3 is able to be used with reduced functionality. DFB4 or CASPSR should be considered as alternatives to DFB3. MBCORR functionality is increasingly being replaced by HIPSR. MBCORR will only be available when a compelling science case is made for its use.
- Mopra: Mopra is no longer being offered as a National Facility telescope.
- LBA: LBA proposers are reminded of their responsibility to contribute to LBA observing support.
Target of Opportunity proposals can be submitted at any time.
Large Projects are projects that require a total of more than 400 hours of observing time over the lifetime of the project. Please read the Large Projects web page in addition to the information on this page.
New users are advised to read the information on the ATNF Scientific Support of Facilities. This web page explains the different levels of support provided to proposers and observers.
A document outlining Time Assignment Committee procedures is now available from the TAC web page.
For further information contact the Head of Science Operations, Phil Edwards (Philip.Edwards [at] csiro.au).
The default location for observing with the ATCA is the Marsfield Science Operations Centre (SOC). Observing at the ATCA will still be permitted for complex or non-standard observations, or in other circumstances where this is the more sensible option. Remote observing from other locations is permitted for suitably qualified observers.
For 2015OCT, the array configurations 6A, 6B, 1.5A, 1.5D, 750C, 750D, EW352, EW367, and H214 will be offered. Configurations will only be scheduled if there is sufficient proposal demand for them. The 2015APR semester ends in H168 array, and the ATCA may remain in this array for the first weeks of the 2015OCT semester and so proposals for this array will also be considered.
The Compact Array Broadband Backend (CABB) modes that will be available for 2015OCT semester are:
- CFB 1M: A bandwidth of 2 GHz with 2048 x 1-MHz channels in each IF band, but no "zoom" bands.
- CFB 1M-0.5k: A bandwidth of 2 GHz with 2048 x 1-MHz channels and (optionally) a fine resolution of 0.5 kHz in up to 16 "zoom" bands (each with 2048 channels across 1 MHz) in each IF band.
- CFB 64M-32k: A bandwidth of 2 GHz with 32 x 64-MHz channels and (optionally) a fine resolution of 32 kHz in up to 16 zoom bands (each with 2048 channels across 64 MHz) in each IF band.
- CFB 1M/64M: A "hybrid" mode with 2048 x 1-MHz (but no zooms) in one IF band, and 32 x 64-MHz channels with (optionally) up to 16 zoom bands with 2048 channels across each 64 MHz in the other IF band.
- Pulsar binning mode: The normal 2048 x 1 MHz continuum band is supplied for each IF band and in addition, for each IF, a time-binned IF band with 512 x 4 MHz channels and 32 time bins across the period of the pulsar. A minimum bin time of 110 micro-seconds is possible, allowing 32 bins across a 3.5 milli-second pulsar period.
- High time-resolution mode: The normal 2048 x 1 MHz continuum band is supplied for each IF band and in addition, for each IF, a time-binned IF band with 512 x 4 MHz channels and either 128 or 32 time bins across the correlator cycle period (normally 10 seconds, but can be routinely set as low as 2 seconds).
For the latest information on CABB, please check the CABB web page.
Compact Array receivers and frequency ranges
The 16-cm band receivers, installed in 2010, provide an instantaneous frequency coverage from 1.1 to 3.1 GHz (although the usable bandwidth is reduced by typically 30% by Radio Frequency Interference [RFI]). The 16-cm band receivers have an improved sensitivity over the original 20- and 13-cm receivers, and include new ortho-mode-transducers, significantly improving the polarisation performance toward the top end of the band.
The 4-cm band receivers, installed in 2012, cover the band from 4 GHz to 10.8 GHz. These receivers provide significantly improved system temperatures over the original 6- and 3-cm receivers. CA03 and CA05 have new prototype feeds horns to extend the frequency coverage to 12 GHz. (A consequence of this is that the focus positions for these two antennas differ from those of other bands. This should be borne in mind if changing between bands during an observation. It takes about 1 minute to refocus the antennas.)
In the 15-mm (16--25 GHz), 7-mm (30--50 GHz) and 3-mm (83.5--106 GHz) bands, two 2GHz-wide intermediate frequency bands may be selected within an 8 GHz bandwidth. In the 7-mm band, both band centres must be either greater than 41 GHz (the point at which the conversion changes from lower side-band to upper side-band) or both less than 41 GHz. Observing is possible with the standard 15-mm and 7-mm systems on all six antennas, and 3-mm systems on five antennas: there is no 3mm receiver on CA06.
The ATCA sensitivity calculator provides a means of determining the sensitivity characteristics of observations, and can include the reduction in bandwidth expected due to RFI in the 16cm band.
Observing at 3 mm generally starts in May and ends in mid-October. Proposers are reminded that the primary flux density calibrator at 3 mm is Uranus, which in October 2015 will be near a R.A. of 1h10m and declination of +6d30m. Proposals for 3-mm observations that require accurate flux calibration should request time for observations of Uranus (if the array configuration allows). For 7-mm observations with CABB, PKS 1934-638 is sufficiently strong to be used as a primary flux density calibrator. However, the flux scale of PKS 1934-638 at frequencies above 25 GHz still requires full characterisation and it is advisable to also observe Uranus at 7 mm in array configurations for which the planet is not resolved. Proposers requiring their own observations of Uranus (at special frequencies, or at a time when their main target has set, for example), should make this clear in the observations table and justification of their proposal. For secondary calibration at 3- and 7-mm, Observatory staff will calibrate a number of bright AGN, spread over the full range of R.A., against Uranus at the standard continuum observing frequencies throughout the semester.
The array has been outfitted with Water Vapour Radiometers (WVRs) provided by the University of New South Wales. Experience to date indicates that these units will, in some conditions, allow corrections to the measured phases on longer baselines to be made, improving phase stability and sensitivity. Interested mm-wavelength observers will be able to use of this capability during 2015OCT. Details of the system are available at the WVR webpage.
- Latest information on the Compact Array Broadband Backend (CABB)
- The Australia Telescope Compact Array User Guide describes how to apply for observing time, make a schedule file, and carry out observations with the ATCA.
- Target of Opportunity and NAPA (Non A Priori Assignable) proposals
- For further information contact the ATCA Lead Scientist, Jamie Stevens (Jamie.Stevens [at] csiro.au).
Remote observing with the Parkes telescope from the Marsfield Science Operations Centre (SOC) is now the default mode of observing. Observing from Parkes will still be permitted for complex or non-standard observations, or in other circumstances where this is the more sensible option. Remote observing from other locations is permitted for suitably qualified observers.
It is expected that proposal teams with experienced Parkes observers will be self-sufficient, with a member of each team being designated the Project Expert and being the first point of contact (most often remotely) for questions relating to the observations after work hours. Inexperienced teams are encouraged to seek experienced collaborators: if this is not possible, the teams should be prepared to arrive several days before their observations commence in order for observer training to be completed during work hours so that a member of the team is qualified for the Project Expert role. All Parkes proposal teams are asked to nominate on the cover sheets of their proposal the member(s) in their team who will be (or will be trained to be) the Project Expert and who will be the first point of contact after hours. (However, it is recognised that the availability of team members can not be known until the observing schedule has been released.) Observers at the SOC are able to receive assistance from staff (during business hours) with their observing. Local Parkes staff will continue to provide the first point of contact for matters relating to safety of the telescope, and equipment.
Data from Parkes observations are archived in ATOA (the Australia Telescope On-line Archive) or the CSIRO DAP (Data Access Portal). The DAP now handles some high-volume data from pulsar surveys. To manage the archiving process efficiently, it is necessary to know the expected data volume for projects with Terabyte-scale data requirements. This applies in particular to projects that use HIPSR. The cover sheet for Parkes proposals now specifically requests this information for projects that are likely to gather more than 1 Terabyte of data per semester: such proposals must also explicitly discuss their plans for handling such data volumes in their justification. Observers are advised that they should adhere to the observing set-up described in their proposal. Any additional use of HIPSR must be discussed first with the Head of Science Operations (Phil Edwards).
The 20-cm multi-beam receiver will be removed from the focus cabin for an extended period early in the 2015OCT semester to allow the testing and characterising of a Phased Array Feed (PAF) receiver. The PAF will not be available for scientific observing in the 2015OCT Semester. Future opportunities for science with the PAF will be discussed with the community, beginning at the June ATUC meeting. The timescale on which the 20-cm multi-beam receiver will be removed is not yet known: it is likely that some observing with this receiver will be possible early in the semester. It is planned for a number of receiver changes to be made during the semester so that the 10cm/50cm receiver and H-OH receiver (covering 1.2-1.8 GHz) will be available at times during semester. Details of the Parkes receiver fleet and other technical information are available in the Parkes Radio Telescope Users Guide.
Pulsar Digital Filterbanks
The digital filterbanks DFB3 and DFB4 are available, although DFB3 has become limited in its functionality. DFB4 is a similar instrument to DFB3, but contains only one CABB processor and one digitiser rather than the dual digitisers and processors in DFB3. DFB4 has similar characteristics and performance to DFB3 for normal pulsar timing, except for short period pulsars, where DFB3 has had an advantage owing to the extra processing power, however DFB3 "fold" modes have become particularly problematic of late.
Both spectral line and continuum observers are encouraged to use the digital filter-banks for their observations.
The ATNF Parkes Swinburne Recorder (APSR) baseband system has been decommissioned with its functionality replaced by CASPSR, a coherent de-dispersion pulsar backend developed by Swinburne University of Technology, and made available on a shared-risk basis.
The 13-beam digital filterbank, the Berkeley-Parkes-Swinburne Recorder (BPSR) has been replaced by the HIPSR backend, which will be available during 2015OCT on a shared-risk basis while the 20-cm multi-beam receiver is installed. The system allows higher time resolution, and much greater spectral resolution than the analog filterbanks provided (400 kHz versus 3 MHz) and also allows more bits of precision in sampling. In single beam mode, Analog Filter Bank functionality has been replaced by DFB3 and DFB4. (The Analog Filter Banks were decommissioned in September 2013.)
Spectral Line Correlators
Multibeam correlator functionality is increasingly being replaced by HIPSR. HIPSR currently supports two spectral line modes, (i) a bandwidth of 400 MHz on all 13 beams, with 8192 spectral channels per product and (ii) a bandwidth of 200 MHz on all 13 beams, with 16384 spectral channels per product. Currently, only spectral line mode is supported: Continuum and polarisation observations are not offered. Use of the Multibeam correlator for narrower-band modes (4, 8, or 64 MHz bandwidths on all 13 beams, with up to 2048 spectral channels per product) will only be possible when a compelling science case has been made for its use. Currently, one of the MBCORR samplers is known to be faulty for operations with the 4 and 8 MHz bandwidths, thus only 25 of 26 channels (13 beams, dual IF) can be offered at the two narrowest bandwidths.
The digital filterbanks DFB3 and DFB4 can also be used as spectrometers in both simple and time-binning modes. DFB3 can potentially be used as a two-frequency, dual-polarisation spectrometer with 8192 spectral channels over two bands with bandwidths between 8 and 1024 MHz, although reliability issues may limit the availability of this mode.
Continuum and Polarisation Backends
The digital filterbanks DFB3 and DFB4 can also be used as continuum backends both for total intensity and polarisation observations offering bandwidths up to 1024 MHz and full Stokes products. The number of available frequency channels (512 to 8192) allows spectral behaviour analysis and RFI flagging. In combination with either circular or linear feeds they can be used for Stokes Q & U or Stokes V observations respectively. A time resolution down to 0.25s is achievable in time-binning mode allowing fast scanning options (though note in this mode the maximum number of channels is 4096).
Proposers intending to start a new project are advised to contact the acting Parkes Lead Scientist, George Hobbs (George.Hobbs [at] csiro.au), to discuss their requirements and availability of configurations before proposal submission. For further information on all Parkes facilities please refer to the Parkes Radio Telescope Users Guide.
In the 2015OCT semester the 70-m and 34-m antennas at Tidbinbilla will have limited availability for single-dish use. Tidbinbilla proposals remain active for one year. All observations are taken in a service mode when scheduling permits. Successful proposals require the submission of a source list with accurate target and calibrator positions.
The 70-m antenna is equipped with 1.6, 2.3, 8.4 and 22 GHz receivers and 34-m antennas are equipped with 2.3, 8.4 and 32 GHz receivers. The pointing performance of the 70-m is adequate for observations at the three lowest frequencies (1.6, 2.3 and 8.4 GHz) with no additional calibration, but observations at 22-GHz require a small overhead (~10% of observing time) for determining pointing corrections using bright AGN near the target of interest. It should be noted that the 22 GHz system is the most sensitive in the southern hemisphere, covering 18.0 to 26.5 GHz with a system temperature of 60 Jy. The 8.4 GHz system (also available on the 34-m antenna) is well-suited for radio recombination line observations.
Tidbinbilla is equipped with an ATNF multibeam correlator block capable of two polarisation products, with up to 2048 channels, each with 32 or 64 MHz bandwidth, or up to 4 polarisation products with a total of 8192 channels (e.g., 2 x 4096 channels) and bandwidth of 16 MHz or less.
Full details of available observing time, frequency coverage, correlator capabilities and other technical information are available from the Tidbinbilla Information web page. (See also the NASA Deep Space Communication Complex web pages.) An on-line sensitivity calculator is available to assist in proposal preparation. These pages also include details of current projects.
The second phase of the down-converter upgrade for the 4-channel K-band receiver has recently been completed on the 70m. This new system supports two simultaneous beams per polarisation (four beams in total) across the total frequency coverage of 17 GHz to 27 GHz. An on-the-fly mapping mode has been developed for spectral line observations. The mode has been tested and demonstrated to work with observations of ammonia lines at 23 GHz and radio recombination lines at 8.3 GHz.
For the latest information of availability please refer to the Tidbinbilla website, or contact the ATNF Friend for Tidbinbilla, Yanett Contreras (Yanett.Contreras [at] csiro.au).
For 2015OCT semester, the Long Baseline Array (LBA) will use the Compact Array and Parkes radio telescope, together with the Hobart and Ceduna antennas operated by the University of Tasmania. In addition, the Warkworth 12-m telescope, operated by the Auckland University of Technology, is routinely available at 13 and 3cm, and on occasions at 20cm. A limited amount of time may be available with the Tidbinbilla 70-m antenna or one of the 34-m antennas. A single ASKAP antenna with a single pixel feed at 20cm or 3cm is offered on a best-efforts basis for projects where its use will significantly add to the likely science outcomes. The AuScope Yarragadee and Katherine 12-m antennas may also be available at 13cm or 3cm subject to their availability. The Hartebeesthoek 26-m telescope may also be available subject to its other commitments.
It is planned in the 2015OCT semester to schedule some LBA time at the same time as a European VLBI Network (EVN) session, opening the possibility of joint LBA/EVN observations. The easternmost stations of the EVN are in a similar longitude range to the LBA telescopes, and for sources in equatorial regions, baselines to western European stations are also achievable. Proposals for joint LBA/EVN observations must be submitted separately to both the LBA and EVN at their respective deadlines.
It is now possible to operate the ATCA in hybrid mode where one frequency chain is setup in VLBI mode and the other frequency chain in ATCA continuum mode (2 GHz bandwidth at 1 MHz resolution). Proposers should explicitly request this mode and provide additional scientific justification.
Constraints on Parkes receiver changes impose limits on the frequency of LBA observations with Parkes at wavelengths shorter than the 20cm band.
LBA proposers are reminded that a member (or members) of the proposal team will be required to assist with the VLBI observing on the ATNF telescopes. Please ensure that a member of the proposal team will be able to help. Note that due to logistical constraints the VLBI schedule usually is release only a few weeks before observing, so the observer will need to be qualified for remote observing with Parkes and ATCA, or able to travel to the SOC in Sydney before the LBA session in time to be trained.
Other telescopes may be also requested for special observations. Specific system availability may be dependent on availability at individual antennas. For details consult the ATNF VLBI webpages.
A Novices Guide is available for potential first-time users from the VLBI webpage.
For assistance with planning proposals and observations please consult the VLBI sensitivity calculator.
The current capabilities of the LBA are briefly outlined below:
- The disk-based recording system is now used for all recorded VLBI observations and very high data rates (up to 1 Gbps) can be achieved;
- All recorded observations will be correlated with the DiFX software correlator. The software correlator is capable of correlating the high data rate observations at high spectral resolution with arbitrary correlator integration times;
- Real-time e-VLBI observations are offered, using the ATNF antennas connected together via high-speed links and the DiFX software correlator running at the ATCA. Data-rates for e-VLBI observations of 1 Gbps from each ATNF antenna are now available. Real-time eVLBI capabilities to the Hobart and Warkworth antennas are also now available at 512 Mbps.
The disk-based system is very flexible and can be used to obtain high sensitivity and/or ultra-high spectral resolution observations, useful for a number of novel scientific studies. These facilities improve the compatibility between Australian VLBI antennas and international antennas using other disk-based recording systems such as the Mark5 and K5 systems. User support is available, including assistance with proposal preparation, scheduling, observing and data reduction.
A bit rate of 256 Mbps (2x16MHz bandwidth in 2 polarisations, with 2 bit digitisation and Nyquist sampling) can be sustained at all LBA telescopes and is the standard observing mode. Observations requesting higher bit rates will need to include a clear justification for the requested rate. Potential users must consult the Upgraded VLBI National Facilities capabilities .
For more information contact the LBA Lead Scientist, Chris Phillips (Chris.Phillips [at] csiro.au).