A new drizzled mosaic of the Orion nebula region from WFPC2 images: made by Jeremy Walsh.

Instrument Science & Public Programmes

This page gives an introduction to two facets of the ECF work. A summary is available as PDF viewgraphs:

1) Instrument science collaborations with the STScI and the IDTs.

2) Observing programmes producing non-proprietary data - notably the Cycle 7 public parallel program.

Instrument science collaborations

An increasing fraction of ECF effort is moving from routine user support to direct instrument science support of the HST project (see the Mid-term Review report). This has been particularly true for pre- and post-launch work with STIS and NICMOS - both of which are complex instruments to operate and calibrate.

The ECF philosophy has been to choose significant projects which are reasonably self-contained - therefore not requiring daily coordination with STScI or IDT - but scientificaly beneficial to the user community. An example is the development of slitless spectroscopy s/w for NICMOS. In order to ensure proper information flow and for the purpose of setting of priorities, twice yearly meetings are held between Benvenuti and Fosbury (ECF) and Schreier and Long (STScI). This is in addition to frequent contact with IDT members. While the work on these longer-term projects is carried out mostly at the ECF, there are frequent visits of ECF staff to STScI to work on general issues of pipeline testing and calibration. Such visits last typically a week or two and contribute very positively to the atmosphere of cooperation between the groups.

Major programmes currently underway are:

Instrument Physical Modelling project - major project to model instrument performance from physical principles: applications to HST, VLT (and NGST)

NICMOS - principally concerned with the reduction and analysis of Camera 3 grism data. Necessary development of TinyTim. . Details to be given in splinter session.

STIS - including physical modelling, MAMA history images, CCD spectroscopy contemporaneous flat fielding, spectral extraction (slit and slitless), pipeline and calibration tasks, incorporation into TinyTim PSF generator. Details to be given in splinter session.

ACS - development of the slitless spectroscopy capabilities using the experience gained with NICMOS and STIS.

FOS final archive - calibration re-assessment in preparation for the final archive of FOS spectroscopy.

Polarimetry - consideration is being given to the development of polarimetric analysis s/w for NICMOS WFPC 2 and ACS - this would require extra resources.

Algorithm development - there is a continuing effort to develop innovative algorithms for HST and groundbased data analysis. Examples are image deconvolution and data fusion techniques .

Non-proprietary programmes

Following the HDF exercise, there are now a number of HST observing programmes which produce data which are either immediately non-proprietary or, as for some GO survey projects, become public after a shorter than usual period. This means that, in addition to the growing riches of completed programmes in the archive, there are opportunities for researchers to access large quantities of new data without ever making an observing proposal.

The installation of the solid-state 'tape' recorder during the second servicing mission has greatly increased the capability of HST to operate its instruments in parallel. Since only a small fraction of these parallel opportunities were allocated by the Cycle 7 TAC, the STScI appointed a "Parallel Working Group" (PWG) in the middle of 1997 to design generic parallel programmes for NICMOS, STIS and WFPC 2.

Implementing the parallel programmes is being carried out in two stages since the software developments required are substantial. From June 1997 (earlier for WFPC 2) simple 'unscripted' parallel observations were commenced whenever the schduling opportunities arose. These data are available from both the ECF and the STScI. From early 1998, the scripted programmes devised by the PWG will start to be scheduled.

The considerations of the Parallel Working Group are represented graphically in a cartoon. The text of the PWG report is available via http://archive.stsci.edu/hst/parallels/

The ECF is involved in several aspects of these parallel programmes - from participation in the PWG to calibration and routine processing of some of the data stream. In particular, we are working on the NICMOS grism parallel programmes and, in collaboration with MPA, using STIS direct imaging to study cosmic shear. Some illustrations of STIS imaging the shear project are to be found here and for stellar photometry, here. An excellent example of a one-orbit 50CCD STIS exposure is the test observation of the quasar in the HDF-S field.

Given the success of HDF-N , the STScI director has decided to use a fraction of his discretionary time in 1998 to HDF-S.