General Comments:

 The paper describes the observed properties of the beams of the two

 frequency bands of SWI onboard Juice. For this a point source and an

 extended source (earth) were repeatedly observed to construct 1D cuts

 and 2D maps. These allowed to derive half-power beamwidths,

 ellipticity, alignment, pointing and errors. Beam properties were

 compared with simulations of the far-field beam pattern.  The paper

 is well written, to the point, concise, and represents an important

 contribution to the success of this mission. I still have a couple of

 largely minor points:

 Table 1 gives a mean of CTS1 FWHM_AT of 8.32+-0.07.  How is this

   error of 0.07 derived ? What is it ?  The standard deviation of the

   measured FWHMs is much larger, 0.78 ! This comment concerns all

   errors or 1sigma values given in the paper.

Specific Comments:

 + Abstract: say that the calibration efficiency factor was obtained

   from simulations only.

   

 + Sec.2: CTS has 1GHz or 4.4GHz bandwidths ? The text is confusing.

 

 + Sec.3.1: When discussing observations of a point source,

   which source was actually observed and what was its angular diameter ? 

 + "...scans that cross the limb of the target" for targets

   that are much larger than the main beam.

 + Sec.4: Observations are done in DSB mode, i.e. both sidebands are observed

   simultaneously. When comparing the observations with the GRASP

   simulations, how were the two sidebands taken into account ?

 + Sec.3.1.1: "samling >=2arcmin" Better give range of sampling,

   i.e. 2' to 6'.

 + "two pairs of observations" Scanning Back and forth ?

 + Figure 1: The CT scans show the temperatures to vary over the

   limb of earth. For 1107.45GHz, there even is a discontinuity.

   I suggest to add a sentence, describing in how are such effects

   were taken into account and how they may effect the overall

   accuracy of the beam properties.

 + Figure 6: The extended main beam seems to be not exactly

   symmetrical, showing a broadening or "shoulder" at negative

   offsets, which is especially prominent at CT 1119GHz.

   This seems worth mentioning. In the future, 2D maps may help to

   study this feature in more detail.

 + "mb=3xFWHM" seems arbitry. Maybe say that this corresponds

   roughly to the main beam down to the 1st null of the simulated

   diffraction pattern.

Technical Corrections:

 + slated -> scheduled/foreseen to arrive...

 + Sec.2: Say that each band is observed in single polarisation

 + Sec.3.1.2 "arrange the measured data by" -> plot as function of...

 + "fit them with a model" refer to section in which the model is presented.

 + Figure 4: Explain the white circle in the centers.