SINFONI pipeline:
Science files and recipes

SINFONI SCIENCE data have been processed by the pipeline with the best available calibration data. Please note that ESO is not assuming any responsibility in respect to the usefulness of the reduced data. The adopted reduction strategy may not be suitable for the scientific purpose of the observations.

Notes. The SINFONI science recipe sinfo_rec_jitter provides several ways to subtract the sky spectrum and to coadd individual cubes (PRO.CATG = OBS_OBJ) to a coadded cube (PRO.CATG = COADD_OBJ). The strategy does not depend on the used template but on the number of raw SCIENCE input frames and the number of frames with DPR.TYPE = SKY_NODDING.

pipeline version 2.0.8:

In case the science raw file stack contains SKY frames, the closest in times observed SKY frame is extracted from each DPR.TYPE = OBJECT frame. The SKY subtracted OBJECT frames are coadded, according to the information given in the CUMOFFSET fits header keys. The offsets in pixel units are PixelX = -2 * CUMOFFSETX; PixelY = 2 * CUMOFFSETY (this convention may change from Oct 1, P76 on).

In case the science raw file stack does not contain any SKY frames, several strategies are provided

1. MEDIAN_STACKING: The parameter sinfo.objnod.autojitter_method=2 in the configuration file sinfo_rec_jitter. The median of each pixel is considered to be SKY and is subtracted from each OBS_OBJ frame.
   The following example of four OBS_OBJ cubes (here the median collapsed in z is shown with 99%-cuts)
   

   frame 1 minus frame 2	frame 2 minus frame 1
   frame 3 minus frame 2	frame 4 minus frame 3

   
   The final coadded product (again median collapsed) looks like this:
   
   The first sky subtracted cube appears in the center of the final COADD_OBJ cube. The three other cubes are coadded accordingly.
   
   
2. SKY_IS_NEXT: The parameter sinfo.objnod.autojitter_method=1 in the configuration file sinfo_rec_jitter. Pairs of consecutive OBS_OBJ frames are generated, of which one is subtracted from the other as sky. Sources in the subtracted frame appear as sources with negative flux in the final COADD_OBJ product.
   The following example of four OBS_OBJ cubes (here the median collapsed in z is shown with 99%-cuts)
   

   frame 1 minus frame 2	frame 2 minus frame 1
   frame 3 minus frame 2	frame 4 minus frame 3

   The left negative source is twice as strong, since it is frame 3 (subtracted from frame 4) and frame 2 (subtracted from frame 1). The closest in time frame of the stack is used as sky to be subtrcated. It can be the previous or the next frame of the science stack.
   The final coadded product (again median collapsed) looks like this:
   
   
   
3. The sinfo.objnod.autojitter_method=0 in the configuration file sinfo_rec_jitter. No sky is subtracted.

pipeline version 2.0.8 (used for date from ~2009-10-10 on), as for 1.0.6, SKY frames are subtracted, in case they are part of the raw frame stack. If there is no SKY frame given, then:

1. sinfo.objnod.autojitter_method=0 in the configuration file sinfo_rec_jitter : No sky subtraction. This method is also applied in case a single OBJECT raw frame is submitted (no SKY).
2. sinfo.objnod.autojitter_method=1 in the configuration file sinfo_rec_jitter :
   use SKY_IS_NEXT method
   subtract the dummy sky from the OBJECT
   each processed OBJECT frame is cube reconstructed (PRO.CATG = OBS_OBJ):
   jitter_int = 1 : coadded cube is generated
   scales_sky = TRUE : spatial median subtracted from each plane of the reconstructed cube to take out temporal residuals of the sky
   ks_clip = TRUE : kappa-sigma clipping applied to each pixel after cube aligning (= in the set of co-aligned OBJECT frames), to mask cosmics and hot pixels.
3. sinfo.objnod.autojitter_method=2 in the configuration file sinfo_rec_jitter: SKY_IS_NEXT method
4. sinfo.objnod.autojitter_method=3 in the configuration file sinfo_rec_jitter: MEDIAN_STACKING method

Defaults: sinfo.objnod.autojitter_method=1 scales_sky = FALSE , ks_clip = FALSE, jitter_int = 1

Science products of service mode packages use :

• sinfo.objnod.autojitter_method=1
• scales_sky = TRUE
• ks_clip = TRUE
• jitter_int = 1

In case science stacks contain embeded SKY frames, it is assumed there are reasons for that observing strategy (e.g. filamenteous background). In this case the SKY frames itself are used to correct OBJECT frames.

pipeline version 1.0.9 (used for date from ~2005-07-06 on)

1. sinfo.objnod.autojitter_method=0 in the configuration file sinfo_rec_jitter : No sky subtraction. This method is also applied in case a single OBJECT raw frame is submitted (no SKY).
2. sinfo.objnod.autojitter_method=1 in the configuration file sinfo_rec_jitter :
   use SKY_IS_NEXT method
   subtract the dummy sky from the OBJECT
3. sinfo.objnod.autojitter_method=2 in the configuration file sinfo_rec_jitter: MEDIAN_STACKING method

Defaults: sinfo.objnod.autojitter_method=1 scales_sky = FALSE , ks_clip = FALSE, jitter_int = 1

Science products of service mode packages use :

• sinfo.objnod.autojitter_method=0 : The individual object cubes are not sky subtracted. SKY is subtracted as part of the co-adding.
• scales_sky = TRUE
• ks_clip = TRUE
• jitter_int = 1

Input

Products.

QC parameters

Quality plots. Since April 2005, we deliver in the Service Mode packages a set of quality control plots.

Medusa. The first QC plot for the Medusa setups has the following elements:

1. a crosscut through the raw frame (row @2048)
2. a closeup of box 1, displaying the central 200 pixels with the fibre PSF and the BIAS level indicated by the red broken line
3. from the extracted and rebinned spectrum file, a vertical collapse indicating the mean signal per fibre
4. a selection of spectra (rebinned for display):

   a) the fibre with the lowest nominal magnitude (read from the ozpoz table), assumed to represent the sky signal

   b) the fibre with the brightest nominal magnitude (again read from the ozpoz table; if none found, fibre 10 is displayed)

   c) S/N for the fibre selected in b), derived by division of the spectrum by the corresponding error in the RBN_ERRORS file (SRBE)

   Both the signal and S/N are plotted under 'slope' with a compressed horizontal scale. The strategy to find the faintest and the brightest fibre assumes the usual magnitudes. If the user has chosen a different convention, the guess may fail.

For spectra above 585 nm, sky emission lines are marked in 4a (red vertical lines), and telluric absorption lines are marked in 4b (blue vertical lines). The emission lines (at UVES resolution) are taken from Hanuschik (2003). The list of telluric lines at the UVES resolution is not yet published.

Three more QC plots for the Medusa modes display all extracted spectra, along with their user-provided target name and magnitude. The figure below shows an example for fibres 1-45. n/a means 'not allocated'.

The Argus and IFU settings also have a set of QC plots. The first one is very similar to the Medusa case, with the faintest object fibre showed under 4a, the integrated signal from all fibres of subslit #6 under 4b, and the S/N for the first fibre from #6. This selection has been made since Argus and IFU spectra are not independent of each other. The guess of the faintest object may fail under the same conditions as described in the Medusa case.

Instead of a preview of all fibres, for Argus and IFU the reconstructed image (RCSPECTRA) is available as preview. It has been obtained by collapsing the spectra into a single number per fibre and display that value on a relative spatial grid. The mapping between fibre index and spatial coordinates has been provided by the pipeline (Fig. 2.7 of the FLAMES manual). Note this is a collapse of the whole spectrum. A narrow-band image in an emission-line can look rather different. Also note that this image is not sky subtracted (but the sky signal is available).