Calibration data for NACO are taken for two purposes:

• assess the instrument status
• reduce science data

Generally NACO calibration data are taken as daytime calibrations. On request of the user, also nighttime calibrations can be obtained as part of the Observing Block which generates the SCIENCE data ("attached calibrations").

All calibration data taken by NACO are processed by QC Garching to obtain calibration solutions. These solutions come as

• calibration product fits file frames (e.g. dark or twilight flat frames)
• calibration product paf (e.g. zeropoints)

The following types of raw calibration data exist for the NACO IMAGINGmode

frame DPR TYPE Purpose typical number taken per night and setting DARK DARK detector status, dark level, RON, hot pixels 3 TWILIGHT FLAT SKY,FLAT fixed pattern noise, vignetting, odd-even columns effect, bad pixels 10 SKY FLAT SKY,FLAT as Twilight flats 15-25 LAMP FLAT LAMP,FLAT fixed pattern noise, vignetting 3 ON and three OFF frames ZEROPOINTS STD standard stars for photometric zeropoints 5

The following types of raw calibration data exist for the NACO POLARIMETRY mode

The following types of raw calibration data exist for the NACO SPECTROSCOPY mode

Recipes and products

The following NACO calibration products are created from raw calibration files (click here for a complete overview of calibration files and recipes):

raw frame(s) recipe description product(s) DARK naco_img_dark   create a master dark from set of input raw frames and calculates the RON MASTER_DARK, RON paf , hot pixel map, cold pixel map TWILIGHT FLAT naco_img_twflat create a master twilight flat and checks detector linearity from set of 10 raw image FLAT FRAME, BAD PIXEL MAP, ERROR MAP, (INTERCEPTION MAP) SKY FLAT naco_img_twflat create a master skyflat and checks detector linearity from set of 10 raw image FLAT FRAME, BAD PIXEL MAP, ERROR MAP, (INTERCEPTION MAP) LAMP FLAT naco_img_lampflat create a master skyflat and checks gain, lamp flux and fixed pattern noise FLAT FRAME, QC PAF ZEROPOINT naco_img_zpoint obtain photometric zeropoint ZEROPOINT PAF

* not produced by QC Garching

Naming scheme

After production and certification, the calibration products are renamed after a scheme which includes type, creation data and relevant NACO setting. .

NACO calibration
cascade (9K)

NACO calibration frames requires a cascading scheme where the mutual dependencies of products and raw frames have to be respected. Some products (startrace tables, arc tables) can be produced from raw files only, but most products require the prior generation of other calibration products. The proper sequence of all these production steps is called the calibration cascade.

Within that cascade, all products are checked with respect to their quality and their relationship in time. This means e.g. that a master flat is not only generated using an arbitrary quality-checked order table, but that specific table is chosen which at the moment of processing is closest in time.

All products created by QC Garching follow the calibration cascade.

(under construction)

NACO Pipeline problems are documented under on the ServiceMode page.