APEX - Recent Changes in Period 98

This section describes relevant changes for observations to take place during Period 98.


  • During Period 98, the ESO time slots are expected to be scheduled in early August, late September to early October and early December.
  • The exact distribution of the observing time between the APEX partners can be found on the APEX web pages. Time-critical observations should only be requested during the ESO runs.
  • Large Programmes with APEX using Poor PWV conditions: In order to make the best use of the time where the PWV is high (PWV>2 mm) ESO invites Large Programmes for those conditions. Poor PWV large programmes must be clearly identi ed as such in Box 5 and 8 of the large programme proposal form. Ideally a "Poor PWV LP Programme" therefore consists of a large sample of targets covering a wide RA range. The proposal must demonstrate that the scienti c goals can be reached with only a signi cant subset of the observations completed. Poor PWV-LPs may cover up to 3 consecutive semesters.
  • Large and Monitoring programmes can cover only 3 periods, until the end of the current APEX agreement.


  • This new 350 μm camera ARTEMIS is offered conditional to its successful commissioning in May 2016. ARTEMIS will cover a field of view of 4'x2' at 350µm. Parallel observations at 450 μm may be available, but cannot be guaranteed. Sensitivity estimations for 450 μm will not be available before the deadline, and the science case should not depend on this band. If the commissioning is delayed, ESO may execute ARTEMIS programmes with SABOCA instead. An  observing time calculator is available
  • SABOCA  is not offered in Period 98 as the same capabilities are offered by ARTEMIS.
  • SHFI:
    • APEX-1: Large proposals for PWV>2mm conditions are encouraged.
    • Programmes which would benefit from the wider bandwidth, higher sensitivity or increased baseline stability of the new 230 GHz MPIfR receiver can optionally request to execute their programmes with this new receiver, pending successful commissioning, and only in collaboration and after prior approval by the instrument PI, Rolf Guesten (rguesten[AT]mpifr-bonn.mpg.de).
  • FLASH:
    • This PI instruments is offered to the ESO community on a collaborative basis with MPIfR. Large programmes or time critical observations with PI instruments will not be accepted. Users who would like to use FLASH must contact the instrument PI, Dr. Rolf Guesten (rguesten[AT]mpifr-bonn.mpg.de), at least two weeks prior to submitting their proposal. Members of the PI team should be included as CoIs on the proposal. The operation of these PI instruments requires the presence of the instrument team so all ESO FLASH and observations will be scheduled on fixed dates; the exact dates have not been determined yet.
    • Observations will be done by the PI team during a maximum of 3 days. Preference will be given to proposals using the dual-beam, wide-bandwidth capabilities of FLASH due to limited ESO observing time.
  • CHAMP+: This MPIfR PI instrument is not offered in Period 98 due to a planned technical intervention. It may be offered again in Period 99.
  • SEPIA: This instrument can house up to 3 ALMA-type receiver cartridges. The band 5 receiver, covering 159 to 211 GHz with dual polarization, sideband-separating mixers, has successfully completed commissioning in September 2015, and is now available for Normal, Large and Monitoring programmes. The commissioning of the band 9 receiver, covering 600 to 722 GHz with dual polarization in double side-band mode, has started in February 2016, and is expected to be completed in April 2016. Conditional to a successful completion of the commissioning and science verification, this receiver is offered for regular programmes in Period 98. No Monitoring or Large programmes will be accepted for SEPIA band 9 in Period 98. Both receivers use the XFFTS backends, covering 4 GHz IF bandwidth. In the 2SB receiver of band 5, both bands are recorded, while in the DSB receiver of band 9, only one band is recorded. In both cases, there is a gap of 8 GHz between the image and signal bands. An observing time calculator is available.
    The Late Breaking News page should be checked for updates on the commissioning on the band 9 as it will continue after the release of the call for proposals.