Table 1: Main journal of the spectroscopic observations of the HD152248 system. The first column lists the heliocentric Julian date (HJD). The second gives the observational phase as computed from our He I $\lambda$ 4471 RV orbital solution (cf. Table 3). Columns 3 and 4 (resp. 5 and 6) provide the He I $\lambda$ 4471 line RV (resp. the mean RV) for the primary and secondary stars, in the ``zero systemic velocity'' reference frame (cf. text). The number of lines used to compute the mean RV is given in Col. 7 and the last column provides information about the instrumentation used
HJD $\phi$ He I $\lambda$ 4471 $-\overline{\gamma_{4471}}$ $\overline{RV_{\lambda}-\overline{\gamma_{\lambda}}}$ n Instrument.

$-2\,450\,000$ RV₁ RV₂ RV₁ RV₂

205.859 0.851 207.4 -208.0 212.7 -214.0 6 ESO 1.5 m + B&C

206.852 0.022 -11.6 -11.6 -56.3 38.1 6 ESO 1.5 m + B&C

207.816 0.188 -207.2 203.6 -200.8 204.2 6 ESO 1.5 m + B&C

208.795 0.356 -156.1 155.8 -166.8 164.4 6 ESO 1.5 m + B&C

208.879 0.370 -150.4 136.7 -148.9 164.1 6 ESO 1.5 m + B&C

209.789 0.527 -7.5 -7.5 1.7 1.7 6 ESO 1.5 m + B&C

209.903 0.546 -7.0 -7.0 -10.4 -8.6 6 ESO 1.5 m + B&C

210.782 0.698 167.3 -173.9 184.7 -167.2 6 ESO 1.5 m + B&C

210.910 0.720 187.2 -196.4 183.8 -199.2 6 ESO 1.5 m + B&C

211.777 0.869 186.7 -187.8 203.2 -180.6 6 ESO 1.5 m + B&C

211.912 0.892 175.0 -177.9 194.8 -178.9 6 ESO 1.5 m + B&C

534.902 0.426 -75.7 129.5 -110.3 95.9 6 ESO 1.5 m + B&C

535.904 0.599 70.7 -110.5 91.1 -114.9 6 ESO 1.5 m + B&C

536.888 0.768 213.2 -208.9 209.1 -210.1 6 ESO 1.5 m + B&C

537.897 0.941 98.7 -73.8 116.9 -121.8 6 ESO 1.5 m + B&C

538.889 0.112 -165.6 135.6 -163.5 156.3 6 ESO 1.5 m + B&C

539.907 0.287 -201.4 191.8 -200.0 191.5 6 ESO 1.5 m + B&C

531.908 0.912 160.2 -155.2 160.2 -155.2 1 CAT + CES + LC

532.881 0.079 -97.9 122.7 -97.9 122.7 1 CAT + CES + LC

533.859 0.247 -206.7 219.7 -206.7 219.7 1 CAT + CES + LC

534.844 0.416 -99.7 108.2 -99.7 108.2 1 CAT + CES + LC

535.859 0.591 48.7 -85.6 48.7 -85.6 1 CAT + CES + LC

536.856 0.762 219.0 -201.2 219.0 -201.2 1 CAT + CES + LC

622.604 0.506 -4.9 1.9 -4.9 1.9 1 CAT + CES + LC

623.628 0.682 154.2 -170.8 154.2 -170.8 1 CAT + CES + LC

624.554 0.841 215.8 -211.1 215.8 -211.1 1 CAT + CES + LC

625.607 0.022 -2.2 -2.2 -2.2 -2.2 1 CAT + CES + LC

626.571 0.188 -202.0 214.9 -202.0 214.9 1 CAT + CES + LC

1000.668 0.509 0.3 3.1 0.3 3.1 1 CAT + CES + VLC

1299.817 0.945 136.7 -91.8 130.4 -103.7 11 ESO 1.5 m + FEROS

1300.809 0.115 -147.8 163.4 -150.5 166.8 11 ESO 1.5 m + FEROS

1301.815 0.288 -204.3 202.5 -202.4 194.7 11 ESO 1.5 m + FEROS

1302.808 0.459 -12.9 -12.9 -50.1 42.6 11 ESO 1.5 m + FEROS

1304.889 0.817 223.2 -213.0 213.0 -210.3 11 ESO 1.5 m + FEROS

1323.740 0.058 -88.6 49.4 -86.8 76.5 11 ESO 1.5 m + FEROS

1327.780 0.753 199.2 -202.4 200.7 -202.9 11 ESO 1.5 m + FEROS

1328.734 0.917 151.8 -150.2 158.2 -144.5 6 CTIO 1.5 m + BME

1329.738 0.089 -130.2 117.9 -122.6 136.2 6 CTIO 1.5 m + BME

1330.739 0.261 -215.9 194.0 -212.9 184.1 6 CTIO 1.5 m + BME

1331.771 0.439 -81.4 36.7 -91.5 60.6 6 CTIO 1.5 m + BME

1332.798 0.615 84.8 -108.4 94.7 -107.2 6 CTIO 1.5 m + BME

1668.832 0.393 -108.1 131.5 -120.5 125.2 11 ESO 1.5 m + FEROS

1669.853 0.568 36.0 -42.3 37.2 -51.4 11 ESO 1.5 m + FEROS

1670.836 0.737 206.7 -190.0 204.2 -188.4 11 ESO 1.5 m + FEROS

1671.839 0.910 157.9 -158.6 163.2 -159.3 11 ESO 1.5 m + FEROS

1672.828 0.080 -122.7 102.1 -120.9 111.4 11 ESO 1.5 m + FEROS

1673.809 0.248 -203.6 217.2 -206.4 207.6 11 ESO 1.5 m + FEROS

**Table 1:** Main journal of the spectroscopic observations of the HD152248 system. The first column lists the heliocentric Julian date (HJD). The second gives the observational phase as computed from our He I $\lambda$ 4471 RV orbital solution (cf. Table 3). Columns 3 and 4 (resp. 5 and 6) provide the He I $\lambda$ 4471 line RV (resp. the mean RV) for the primary and secondary stars, in the ``zero systemic velocity'' reference frame (cf. text). The number of lines used to compute the mean RV is given in Col. 7 and the last column provides information about the instrumentation used
HJD	$\phi$	He I $\lambda$ 4471 $-\overline{\gamma_{4471}}$	$\overline{RV_{\lambda}-\overline{\gamma_{\lambda}}}$	n	Instrument.
$-2\,450\,000$		RV₁	RV₂	RV₁	RV₂
205.859	0.851	207.4	-208.0	212.7	-214.0	6	ESO 1.5 m + B&C
206.852	0.022	-11.6	-11.6	-56.3	38.1	6	ESO 1.5 m + B&C
207.816	0.188	-207.2	203.6	-200.8	204.2	6	ESO 1.5 m + B&C
208.795	0.356	-156.1	155.8	-166.8	164.4	6	ESO 1.5 m + B&C
208.879	0.370	-150.4	136.7	-148.9	164.1	6	ESO 1.5 m + B&C
209.789	0.527	-7.5	-7.5	1.7	1.7	6	ESO 1.5 m + B&C
209.903	0.546	-7.0	-7.0	-10.4	-8.6	6	ESO 1.5 m + B&C
210.782	0.698	167.3	-173.9	184.7	-167.2	6	ESO 1.5 m + B&C
210.910	0.720	187.2	-196.4	183.8	-199.2	6	ESO 1.5 m + B&C
211.777	0.869	186.7	-187.8	203.2	-180.6	6	ESO 1.5 m + B&C
211.912	0.892	175.0	-177.9	194.8	-178.9	6	ESO 1.5 m + B&C
534.902	0.426	-75.7	129.5	-110.3	95.9	6	ESO 1.5 m + B&C
535.904	0.599	70.7	-110.5	91.1	-114.9	6	ESO 1.5 m + B&C
536.888	0.768	213.2	-208.9	209.1	-210.1	6	ESO 1.5 m + B&C
537.897	0.941	98.7	-73.8	116.9	-121.8	6	ESO 1.5 m + B&C
538.889	0.112	-165.6	135.6	-163.5	156.3	6	ESO 1.5 m + B&C
539.907	0.287	-201.4	191.8	-200.0	191.5	6	ESO 1.5 m + B&C
531.908	0.912	160.2	-155.2	160.2	-155.2	1	CAT + CES + LC
532.881	0.079	-97.9	122.7	-97.9	122.7	1	CAT + CES + LC
533.859	0.247	-206.7	219.7	-206.7	219.7	1	CAT + CES + LC
534.844	0.416	-99.7	108.2	-99.7	108.2	1	CAT + CES + LC
535.859	0.591	48.7	-85.6	48.7	-85.6	1	CAT + CES + LC
536.856	0.762	219.0	-201.2	219.0	-201.2	1	CAT + CES + LC
622.604	0.506	-4.9	1.9	-4.9	1.9	1	CAT + CES + LC
623.628	0.682	154.2	-170.8	154.2	-170.8	1	CAT + CES + LC
624.554	0.841	215.8	-211.1	215.8	-211.1	1	CAT + CES + LC
625.607	0.022	-2.2	-2.2	-2.2	-2.2	1	CAT + CES + LC
626.571	0.188	-202.0	214.9	-202.0	214.9	1	CAT + CES + LC
1000.668	0.509	0.3	3.1	0.3	3.1	1	CAT + CES + VLC
1299.817	0.945	136.7	-91.8	130.4	-103.7	11	ESO 1.5 m + FEROS
1300.809	0.115	-147.8	163.4	-150.5	166.8	11	ESO 1.5 m + FEROS
1301.815	0.288	-204.3	202.5	-202.4	194.7	11	ESO 1.5 m + FEROS
1302.808	0.459	-12.9	-12.9	-50.1	42.6	11	ESO 1.5 m + FEROS
1304.889	0.817	223.2	-213.0	213.0	-210.3	11	ESO 1.5 m + FEROS
1323.740	0.058	-88.6	49.4	-86.8	76.5	11	ESO 1.5 m + FEROS
1327.780	0.753	199.2	-202.4	200.7	-202.9	11	ESO 1.5 m + FEROS
1328.734	0.917	151.8	-150.2	158.2	-144.5	6	CTIO 1.5 m + BME
1329.738	0.089	-130.2	117.9	-122.6	136.2	6	CTIO 1.5 m + BME
1330.739	0.261	-215.9	194.0	-212.9	184.1	6	CTIO 1.5 m + BME
1331.771	0.439	-81.4	36.7	-91.5	60.6	6	CTIO 1.5 m + BME
1332.798	0.615	84.8	-108.4	94.7	-107.2	6	CTIO 1.5 m + BME
1668.832	0.393	-108.1	131.5	-120.5	125.2	11	ESO 1.5 m + FEROS
1669.853	0.568	36.0	-42.3	37.2	-51.4	11	ESO 1.5 m + FEROS
1670.836	0.737	206.7	-190.0	204.2	-188.4	11	ESO 1.5 m + FEROS
1671.839	0.910	157.9	-158.6	163.2	-159.3	11	ESO 1.5 m + FEROS
1672.828	0.080	-122.7	102.1	-120.9	111.4	11	ESO 1.5 m + FEROS
1673.809	0.248	-203.6	217.2	-206.4	207.6	11	ESO 1.5 m + FEROS

During two runs in May 1996 and March 1997, a set of medium resolution spectra was obtained with the Boller & Chivens spectrograph (B&C) fed by the ESO 1.5 m telescope. The detector was a 2k $\times$ 2k UV flooded Loral-Lesser CCD. The pixel size is $15 \times 15~\mu$ m. We used the holographic grating (ESO grating #32) with 2400 lines/mm, providing a spectral resolution of 1.2 Å as measured from the FWHM of the lines of the HeAr comparison spectrum. The covered spectral range extends from $\lambda$ 3790 to $\lambda$ 4765 Å.

High resolution spectra of the He I $\lambda$ 4471, N III $\lambda$ $\lambda$ 4634-4641 and He II $\lambda$ 4686 lines were obtained with ESO's 1.4m Coudé Auxiliary Telescope (CAT) at La Silla, using the Coudé Echelle Spectrometer (CES) equipped with the Long Camera (LC, before March 1998) or the Very Long Camera (VLC, after March 1998). The detector used was ESO CCD#38, a Loral $2688 \times 512$ pixel CCD with a pixel size of $15\times 15\,\mu$ m. The slit width was chosen to achieve a nominal resolving power of 70000-80000. The effective resolving power as derived from the FWHM of the lines of the ThAr calibration exposures is 65000-75000. Typical exposure times were of the order of 20 min and the average S/N ratio is above 150. The wavelength domain is centered on the He I $\lambda$ 4471, N III $\lambda$ 4641 or He II $\lambda$ 4686 lines and is $\sim$ 40Å and $\sim$ 20Å wide for spectra taken with the LC and the VLC respectively.

During three observing runs in April - May 1999, end of May 1999 and May 2000, a set of echelle spectra was taken with the Fiber-fed Extended Range Optical Spectrograph (FEROS) attached to the ESO 1.5m telescope at La Silla. Thirty seven orders corresponding to a wavelength domain from 3650 to 9200Å were observed. Typical exposure times were of the order of 6 min and the average S/N ratio is about 100, 220 and 150 at 4050, 6000 and 7500Å respectively. The spectral resolving power of the FEROS instrument is 48000. The detector was an EEV CCD with $2048 \times 4096$ pixels of $15 \times 15$ $\mu$ m. Finally, another set of echelle spectra over the range 3850 to 5790Å was obtained with the Bench-Mounted Echelle Spectrograph (BME) attached to the 1.5m CTIO Ritchey-Chrétien Telescope, during a 5 night run in June 1999. Forty nine orders were observed using the KPGL2 316linesmm^-1 grating as a cross-disperser. The detector was a Tek2048 CCD with 24 $\mu$ m pixels. The slit width was set to 70 $\mu$ m corresponding to a resolving power of 45 000. Exposure times were of the order of 45 min and the average S/N ratio in the continuum is about 100.

3.2 Data reduction

The B&C and CAT observations were reduced in a standard way using the MIDAS package provided by ESO. Whenever possible, the spectra were rectified using a reference star observed under the same conditions. When such a spectrum was not available the spectra were normalized by fitting a polynomial to the continuum.

We used the FEROS context working under the MIDAS environment to reduce the FEROS echelle spectra. The reduction was performed using the standard option. Most of the unavoidable strong fringes that affect the red part of the spectrum (above 6600Å) are simply corrected by flat-fielding. There are however a few residual fringes near 6670, 7140, 7385 and 7930Å. Finally, the spectra were normalized over a range of a few hundred Å at once by fitting a polynomial of degree 4 or 5 to the continuum. Whenever doubt existed about the quality of the automatic merging between the different orders, we checked our results using the unmerged spectrum. Good agreement between both methods was generally observed. The BME data were reduced using the IRAF package and following the recommendations of the BME User's Manual. The pixel to pixel variations were removed using flat field exposures taken with a very bright light source and a diffusing screen placed inside the spectrograph (so-called milky flats). A first rectification of the extracted echelle orders was carried out with the projector flat exposures. The spectra were then normalized by fitting a low-order polynomial to the continuum.

3 Observations and data reduction

3.1 Observations

3.2 Data reduction