== P3.20	Absolute flux calibration == 

- **Phase**		:	3  
- **Status**		: 	Draft	 
- **Category**	: 	Nighttime testing (functionality and operability) (C5) + Nighttime calibration (C6)
- **Recurrence**	: 	once at commissioning and then for each LSS observation.
- **Duration**	: 	2 hours

**Description**
- Extract spectrum of the host star, to be used to obtain the spectrum in contrast for the companion.

**Prerequisites**
- Authorize SHARK-NIR on the SX side.
- Atmospheric conditions: AO working conditions.
- Bad pixel map, Background or Dark, Flat-field, wavelength calibration. 

**Procedure**
- Preset to the targeted star.
- Eventually, center the star behind the slit occulter.
- Apply an offset using the internal DM to move the star outside the occulting mask (but still into the slit).
- Take the spectrum of the star.

**Templates**
- SHARKNIR_lss_cal_FluxCalibration

**Success criteria**
- Better than 10% for absolute flux calibration.

**Notes**
- Same as activity 7.4 in AD4

**LBTO support**
- AO support

**Date performed and by whom**