One of the most exciting and promising results that became evident after the discovery of the first extrasolar planets is that their host stars seem to be very metal-rich when compared with dwarf stars in the solar neighbourhood (Gonzalez 1998; Santos et al. 2000a - hereafter Paper I; Gonzalez et al. 2001). This result, representing the only link between the presence of planets and a stellar photospheric feature, has been given two main explanations. The first, is based on the classical view that giant planets are formed by runaway accretion of gas on to a "planetesimal'' having up to 10 Earth masses. In such a case, we can expect that the higher the proportion is of dust to gas in the primordial cloud (i.e. metals), and consequently in the resulting proto-planetary disc, the more rapidly and easily may planetesimals, and subsequently the now observed giant planets be built.

Opposing to this view, it had been proposed that the observed metallicity "excess'' may be related to the "pollution'' of the convective envelope of the star by the infall of planets and/or planetesimals (e.g., Gonzalez 1998; Laughlin & Adams 1997; Laughlin 2000; Gonzalez et al. 2001). This pollution can be the result of the "complete'' inward migration of a planet on to the star, the transfer of material from the disc to the star as a result of the migration process (Goldreich & Tremaine 1980; Lin et al. 1996), or to the break-up and infall of a planet(s) on to the surface of the star due to gravitational interactions with other companions (Rasio & Ford 1996). The former point might be particularly important for the short-period systems (Queloz et al. 2000).

Table 1: Volume-limited sample of stars without detected giant planets.
Star $T_{\rm eff}$ $\log{g}$ $\xi_t$ [Fe/H] N(Fe I) N(Fe II) $\sigma(Fe{\sc i})$ $\sigma(Fe{\sc ii})$ Mass

(K) (cgs) (km s^-1) [ $M_{\odot}$ ]

HD 1581 5940 4.44 1.13 -0.15 31 7 0.04 0.05 $0.99\pm0.02$

HD 4391 5955 4.85 1.22 0.01 36 5 0.05 0.09 $1.22\pm0.04$

HD 5133 5015 4.82 0.92 -0.08 36 6 0.05 0.07 $0.81\pm0.04$

HD 7570 6135 4.42 1.46 0.17 35 7 0.04 0.06 $1.19\pm0.02$

HD 10360 5045 4.77 0.89 -0.19 36 5 0.04 0.04 $0.70\pm0.03$

HD 10647 6130 4.45 1.31 -0.03 34 7 0.03 0.05 $1.14\pm0.03$

HD 10700 5370 4.70 1.01 -0.50 38 6 0.04 0.04 $0.68\pm0.02$

HD 14412 5410 4.70 1.01 -0.44 35 6 0.04 0.01 $0.78\pm0.05$

HD 17925 5220 4.60 1.44 0.08 35 6 0.07 0.04 $0.92\pm0.06$

HD 20010 6240 4.27 2.23 -0.20 33 6 0.05 0.08 $1.33\pm0.01$

HD 20766 5770 4.68 1.24 -0.20 35 7 0.04 0.04 $0.97\pm0.04$

HD 20794 5465 4.62 1.04 -0.36 39 7 0.05 0.05 $0.74\pm0.02$

HD 20807 5865 4.59 1.28 -0.22 37 7 0.04 0.04 $0.95\pm0.02$

HD 23249 5135 4.00 1.12 0.17 36 7 0.06 0.08 $0.84\pm0.01$

HD 23356 5035 4.73 0.96 -0.05 36 6 0.06 0.07 $0.83\pm0.03$

HD 23484 5230 4.62 1.13 0.10 37 6 0.05 0.07 $0.92\pm0.06$

HD 26965A 5185 4.73 0.75 -0.26 37 5 0.05 0.03 $0.71\pm0.02$

HD 30495 5880 4.67 1.29 0.03 37 7 0.04 0.03 $1.11\pm0.04$

HD 36435 5510 4.78 1.15 0.03 37 6 0.06 0.03 $1.04\pm0.05$

HD 38858 5750 4.56 1.22 -0.22 36 7 0.04 0.02 $0.91\pm0.02$

HD 39091 5995 4.48 1.30 0.09 37 7 0.04 0.04 $1.10\pm0.02$

HD 40307 4925 4.57 0.79 -0.25 37 4 0.06 0.10 $0.76\pm0.07$

HD 43162 5630 4.57 1.36 -0.02 35 7 0.05 0.04 $0.99\pm0.04$

HD 43834 5620 4.56 1.10 0.12 38 7 0.05 0.05 $0.96\pm0.02$

HD 50281A 4790 4.75 0.85 0.07 31 4 0.05 0.12 $0.79\pm0.01$

HD 53705 5810 4.40 1.18 -0.19 36 7 0.03 0.03 $0.92\pm0.01$

HD 53706 5315 4.50 0.90 -0.22 36 7 0.05 0.08 $0.88\pm0.05$

HD 65907A 5940 4.56 1.19 -0.29 39 7 0.04 0.04 $0.94\pm0.01$

HD 69830 5455 4.56 0.98 0.00 38 7 0.05 0.03 $0.89\pm0.06$

HD 72673 5290 4.68 0.81 -0.33 38 6 0.04 0.04 $0.78\pm0.06$

HD 74576 5080 4.86 1.20 0.04 36 5 0.06 0.05 $0.91\pm0.04$

HD 76151 5825 4.62 1.08 0.15 38 7 0.03 0.04 $1.09\pm0.04$

HD 84117 6140 4.35 1.38 -0.04 34 7 0.04 0.06 $1.14\pm0.01$

HD 189567 5750 4.57 1.21 -0.23 37 7 0.04 0.05 $0.89\pm0.01$

HD 191408A 5025 4.62 0.74 -0.51 37 4 0.06 0.09 $0.61\pm0.04$

HD 192310 5125 4.63 0.88 0.05 36 6 0.06 0.08 $0.78\pm0.04$

HD 196761 5460 4.62 1.00 -0.27 38 7 0.05 0.05 $0.81\pm0.03$

HD 207129 5910 4.53 1.21 -0.01 36 7 0.04 0.03 $1.03\pm0.02$

HD 209100 4700 4.68 0.60 0.01 34 3 0.07 0.06 $0.64\pm0.09$

HD 211415 5925 4.65 1.27 -0.16 35 7 0.03 0.04 $0.99\pm0.02$

HD 216803 4647 4.88 0.90 0.07 28 3 0.07 0.08 0.77^+0.01 _-0.18

HD 222237 4770 4.79 0.35 -0.22 37 3 0.08 0.08 -

HD 222335 5310 4.64 0.97 -0.10 33 5 0.05 0.04 $0.86\pm0.05$

**Table 1:** Volume-limited sample of stars without detected giant planets.
Star	$T_{\rm eff}$	$\log{g}$	$\xi_t$	[Fe/H]	N(Fe I)	N(Fe II)	$\sigma(Fe{\sc i})$	$\sigma(Fe{\sc ii})$	Mass
	(K)	(cgs)	(km s^-1)						[ $M_{\odot}$ ]

HD 1581	5940	4.44	1.13	-0.15	31	7	0.04	0.05	$0.99\pm0.02$
HD 4391	5955	4.85	1.22	0.01	36	5	0.05	0.09	$1.22\pm0.04$
HD 5133	5015	4.82	0.92	-0.08	36	6	0.05	0.07	$0.81\pm0.04$
HD 7570	6135	4.42	1.46	0.17	35	7	0.04	0.06	$1.19\pm0.02$
HD 10360	5045	4.77	0.89	-0.19	36	5	0.04	0.04	$0.70\pm0.03$
HD 10647	6130	4.45	1.31	-0.03	34	7	0.03	0.05	$1.14\pm0.03$
HD 10700	5370	4.70	1.01	-0.50	38	6	0.04	0.04	$0.68\pm0.02$
HD 14412	5410	4.70	1.01	-0.44	35	6	0.04	0.01	$0.78\pm0.05$
HD 17925	5220	4.60	1.44	0.08	35	6	0.07	0.04	$0.92\pm0.06$
HD 20010	6240	4.27	2.23	-0.20	33	6	0.05	0.08	$1.33\pm0.01$
HD 20766	5770	4.68	1.24	-0.20	35	7	0.04	0.04	$0.97\pm0.04$
HD 20794	5465	4.62	1.04	-0.36	39	7	0.05	0.05	$0.74\pm0.02$
HD 20807	5865	4.59	1.28	-0.22	37	7	0.04	0.04	$0.95\pm0.02$
HD 23249	5135	4.00	1.12	0.17	36	7	0.06	0.08	$0.84\pm0.01$
HD 23356	5035	4.73	0.96	-0.05	36	6	0.06	0.07	$0.83\pm0.03$
HD 23484	5230	4.62	1.13	0.10	37	6	0.05	0.07	$0.92\pm0.06$
HD 26965A	5185	4.73	0.75	-0.26	37	5	0.05	0.03	$0.71\pm0.02$
HD 30495	5880	4.67	1.29	0.03	37	7	0.04	0.03	$1.11\pm0.04$
HD 36435	5510	4.78	1.15	0.03	37	6	0.06	0.03	$1.04\pm0.05$
HD 38858	5750	4.56	1.22	-0.22	36	7	0.04	0.02	$0.91\pm0.02$
HD 39091	5995	4.48	1.30	0.09	37	7	0.04	0.04	$1.10\pm0.02$
HD 40307	4925	4.57	0.79	-0.25	37	4	0.06	0.10	$0.76\pm0.07$
HD 43162	5630	4.57	1.36	-0.02	35	7	0.05	0.04	$0.99\pm0.04$
HD 43834	5620	4.56	1.10	0.12	38	7	0.05	0.05	$0.96\pm0.02$
HD 50281A	4790	4.75	0.85	0.07	31	4	0.05	0.12	$0.79\pm0.01$
HD 53705	5810	4.40	1.18	-0.19	36	7	0.03	0.03	$0.92\pm0.01$
HD 53706	5315	4.50	0.90	-0.22	36	7	0.05	0.08	$0.88\pm0.05$
HD 65907A	5940	4.56	1.19	-0.29	39	7	0.04	0.04	$0.94\pm0.01$
HD 69830	5455	4.56	0.98	0.00	38	7	0.05	0.03	$0.89\pm0.06$
HD 72673	5290	4.68	0.81	-0.33	38	6	0.04	0.04	$0.78\pm0.06$
HD 74576	5080	4.86	1.20	0.04	36	5	0.06	0.05	$0.91\pm0.04$
HD 76151	5825	4.62	1.08	0.15	38	7	0.03	0.04	$1.09\pm0.04$
HD 84117	6140	4.35	1.38	-0.04	34	7	0.04	0.06	$1.14\pm0.01$
HD 189567	5750	4.57	1.21	-0.23	37	7	0.04	0.05	$0.89\pm0.01$
HD 191408A	5025	4.62	0.74	-0.51	37	4	0.06	0.09	$0.61\pm0.04$
HD 192310	5125	4.63	0.88	0.05	36	6	0.06	0.08	$0.78\pm0.04$
HD 196761	5460	4.62	1.00	-0.27	38	7	0.05	0.05	$0.81\pm0.03$
HD 207129	5910	4.53	1.21	-0.01	36	7	0.04	0.03	$1.03\pm0.02$
HD 209100	4700	4.68	0.60	0.01	34	3	0.07	0.06	$0.64\pm0.09$
HD 211415	5925	4.65	1.27	-0.16	35	7	0.03	0.04	$0.99\pm0.02$
HD 216803	4647	4.88	0.90	0.07	28	3	0.07	0.08	0.77^+0.01 _-0.18
HD 222237	4770	4.79	0.35	-0.22	37	3	0.08	0.08	-
HD 222335	5310	4.64	0.97	-0.10	33	5	0.05	0.04	$0.86\pm0.05$

Table 2: Determined atmospheric parameters and [Fe/H] for a set of stars with planets and brown dwarf companions (bd).
Star $T_{\rm eff}$ $\log{g}$ $\xi_t$ [Fe/H] Instrument Mass Planet

(k) (cgs) (km s^-1) [ $M_{\odot}$ ] discovery paper

HD 1237 $5555\pm50$ $4.65\pm0.15$ $1.50\pm0.08$ $0.11\pm0.08$ CORALIE $1.01\pm0.04$ Naef et al. (2001a)

HD 6434 $5790\pm40$ $4.56\pm0.20$ $1.40\pm0.10$ $-0.55\pm0.07$ FEROS $0.79\pm0.01$ Queloz et al. (2001)

HD 13445 $5190\pm40$ $4.71\pm0.10$ $0.78\pm0.10$ $-0.20\pm0.06$ CORALIE

HD 13445 $5220\pm40$ $4.70\pm0.10$ $0.85\pm0.07$ $-0.19\pm0.06$ FEROS

HD 13445 (avg) 5205 4.70 0.82 -0.20 - $0.75\pm0.04$ Queloz et al. (2000)

HD 16141 $5805\pm40$ $4.28\pm0.10$ $1.37\pm0.09$ $0.15\pm0.05$ FEROS $1.06\pm0.01$ Marcy et al. (2000)

HD 17051 $6225\pm50$ $4.65\pm0.15$ $1.20\pm0.08$ $0.25\pm0.06$ FEROS $1.26\pm0.02$ Kürster et al. (2000)

HD 19994 $6165\pm40$ $4.13\pm0.20$ $1.49\pm0.10$ $0.23\pm0.06$ CORALIE

HD 19994 $6250\pm40$ $4.27\pm0.10$ $1.56\pm0.08$ $0.30\pm0.06$ FEROS

HD 19994 (avg) 6210 4.20 1.52 0.26 - $1.34\pm0.01$ Queloz et al. (2001)

HD 22049 $5135\pm40$ $4.70\pm0.10$ $1.14\pm0.07$ $-0.07\pm0.06$ CORALIE $0.85\pm0.04$ Hatzes et al. (2000)

HD 28185 $5705\pm40$ $4.59\pm0.10$ $1.09\pm0.06$ $0.24\pm0.05$ CORALIE $0.98\pm0.07$ Mayor et al. (2001b)

HD 38529 $5675\pm40$ $4.01\pm0.15$ $1.39\pm0.09$ $0.39\pm0.06$ FEROS $1.52\pm0.05$ Fisher et al. (2000)

HD 52265 $6075\pm40$ $4.21\pm0.10$ $1.31\pm0.07$ $0.22\pm0.07$ CORALIE

HD 52265 $6120\pm50$ $4.37\pm0.20$ $1.31\pm0.06$ $0.25\pm0.06$ FEROS

HD 52265 (avg) 6100 4.29 1.31 0.24 - $1.18\pm0.01$ Naef et al. (2001a)

Butler et al. (2000)

HD 75289 $6135\pm40$ $4.43\pm0.20$ $1.50\pm0.07$ $0.27\pm0.06$ CORALIE $1.20\pm0.02$ Udry et al. (2000)

HD 82943 $6025\pm40$ $4.54\pm0.10$ $1.10\pm0.07$ $0.33\pm0.06$ CORALIE $1.15\pm0.05$ Naef et al. (2001a)

HD 83443 $5500\pm60$ $4.50\pm0.20$ $1.12\pm0.09$ $0.39\pm0.09$ CORALIE $0.90\pm0.05$ Mayor et al. (2001a)

HD 108147 $6265\pm40$ $4.59\pm0.15$ $1.40\pm0.08$ $0.20\pm0.06$ CORALIE $1.27\pm0.02$ Pepe et al. (in prep.)

HD 121504 $6090\pm40$ $4.73\pm0.10$ $1.35\pm0.08$ $0.17\pm0.06$ CORALIE $1.19\pm0.03$ Queloz et al. (2001)

HD 162020 $^{\rm bd}$ $4830\pm80$ $4.76\pm0.25$ $0.72\pm0.12$ $0.01\pm0.11$ CORALIE - Udry et al. (in prep.)

HD 168746 $5610\pm30$ $4.50\pm0.15$ $1.02\pm0.08$ $-0.06\pm0.05$ CORALIE $0.88\pm0.01$ Pepe et al. (in prep.)

HD 169830 $6300\pm30$ $4.04\pm0.20$ $1.37\pm0.07$ $0.22\pm0.05$ CORALIE $1.42\pm0.01$ Naef et al. (2001a)

HD 190228 $5360\pm40$ $4.02\pm0.10$ $1.12\pm0.08$ $-0.24\pm0.06$ WHT $0.84\pm0.01$ Sivan et al. (2001)

HD 202206 $^{\rm bd}$ $5765\pm40$ $4.75\pm0.20$ $0.99\pm0.09$ $0.37\pm0.07$ CORALIE $1.02\pm0.02$ Udry et al. (in prep.)

HD 210277 $5575\pm30$ $4.44\pm0.10$ $1.12\pm0.08$ $0.23\pm0.05$ FEROS $0.94\pm0.01$ Marcy et al. (1999)

HD 217107 $5660\pm50$ $4.43\pm0.10$ $1.04\pm0.07$ $0.40\pm0.06$ CORALIE

HD 217107 $5655\pm40$ $4.42\pm0.05$ $1.11\pm0.08$ $0.38\pm0.05$ FEROS

HD 217107(avg) 5660 4.42 1.01 0.39 - $0.97\pm0.05$ Fischer et al. (1999)

**Table 2:** Determined atmospheric parameters and [Fe/H] for a set of stars with planets and brown dwarf companions (bd).
Star	$T_{\rm eff}$	$\log{g}$	$\xi_t$	[Fe/H]	Instrument	Mass	Planet
	(k)	(cgs)	(km s^-1)			[ $M_{\odot}$ ]	discovery paper

HD 1237	$5555\pm50$	$4.65\pm0.15$	$1.50\pm0.08$	$0.11\pm0.08$	CORALIE	$1.01\pm0.04$	Naef et al. (2001a)
HD 6434	$5790\pm40$	$4.56\pm0.20$	$1.40\pm0.10$	$-0.55\pm0.07$	FEROS	$0.79\pm0.01$	Queloz et al. (2001)
HD 13445	$5190\pm40$	$4.71\pm0.10$	$0.78\pm0.10$	$-0.20\pm0.06$	CORALIE
HD 13445	$5220\pm40$	$4.70\pm0.10$	$0.85\pm0.07$	$-0.19\pm0.06$	FEROS
HD 13445 (avg)	5205	4.70	0.82	-0.20	-	$0.75\pm0.04$	Queloz et al. (2000)
HD 16141	$5805\pm40$	$4.28\pm0.10$	$1.37\pm0.09$	$0.15\pm0.05$	FEROS	$1.06\pm0.01$	Marcy et al. (2000)
HD 17051	$6225\pm50$	$4.65\pm0.15$	$1.20\pm0.08$	$0.25\pm0.06$	FEROS	$1.26\pm0.02$	Kürster et al. (2000)
HD 19994	$6165\pm40$	$4.13\pm0.20$	$1.49\pm0.10$	$0.23\pm0.06$	CORALIE
HD 19994	$6250\pm40$	$4.27\pm0.10$	$1.56\pm0.08$	$0.30\pm0.06$	FEROS
HD 19994 (avg)	6210	4.20	1.52	0.26	-	$1.34\pm0.01$	Queloz et al. (2001)
HD 22049	$5135\pm40$	$4.70\pm0.10$	$1.14\pm0.07$	$-0.07\pm0.06$	CORALIE	$0.85\pm0.04$	Hatzes et al. (2000)
HD 28185	$5705\pm40$	$4.59\pm0.10$	$1.09\pm0.06$	$0.24\pm0.05$	CORALIE	$0.98\pm0.07$	Mayor et al. (2001b)
HD 38529	$5675\pm40$	$4.01\pm0.15$	$1.39\pm0.09$	$0.39\pm0.06$	FEROS	$1.52\pm0.05$	Fisher et al. (2000)
HD 52265	$6075\pm40$	$4.21\pm0.10$	$1.31\pm0.07$	$0.22\pm0.07$	CORALIE
HD 52265	$6120\pm50$	$4.37\pm0.20$	$1.31\pm0.06$	$0.25\pm0.06$	FEROS
HD 52265 (avg)	6100	4.29	1.31	0.24	-	$1.18\pm0.01$	Naef et al. (2001a)
							Butler et al. (2000)
HD 75289	$6135\pm40$	$4.43\pm0.20$	$1.50\pm0.07$	$0.27\pm0.06$	CORALIE	$1.20\pm0.02$	Udry et al. (2000)
HD 82943	$6025\pm40$	$4.54\pm0.10$	$1.10\pm0.07$	$0.33\pm0.06$	CORALIE	$1.15\pm0.05$	Naef et al. (2001a)
HD 83443	$5500\pm60$	$4.50\pm0.20$	$1.12\pm0.09$	$0.39\pm0.09$	CORALIE	$0.90\pm0.05$	Mayor et al. (2001a)
HD 108147	$6265\pm40$	$4.59\pm0.15$	$1.40\pm0.08$	$0.20\pm0.06$	CORALIE	$1.27\pm0.02$	Pepe et al. (in prep.)
HD 121504	$6090\pm40$	$4.73\pm0.10$	$1.35\pm0.08$	$0.17\pm0.06$	CORALIE	$1.19\pm0.03$	Queloz et al. (2001)
HD 162020 $^{\rm bd}$	$4830\pm80$	$4.76\pm0.25$	$0.72\pm0.12$	$0.01\pm0.11$	CORALIE	-	Udry et al. (in prep.)
HD 168746	$5610\pm30$	$4.50\pm0.15$	$1.02\pm0.08$	$-0.06\pm0.05$	CORALIE	$0.88\pm0.01$	Pepe et al. (in prep.)
HD 169830	$6300\pm30$	$4.04\pm0.20$	$1.37\pm0.07$	$0.22\pm0.05$	CORALIE	$1.42\pm0.01$	Naef et al. (2001a)
HD 190228	$5360\pm40$	$4.02\pm0.10$	$1.12\pm0.08$	$-0.24\pm0.06$	WHT	$0.84\pm0.01$	Sivan et al. (2001)
HD 202206 $^{\rm bd}$	$5765\pm40$	$4.75\pm0.20$	$0.99\pm0.09$	$0.37\pm0.07$	CORALIE	$1.02\pm0.02$	Udry et al. (in prep.)
HD 210277	$5575\pm30$	$4.44\pm0.10$	$1.12\pm0.08$	$0.23\pm0.05$	FEROS	$0.94\pm0.01$	Marcy et al. (1999)
HD 217107	$5660\pm50$	$4.43\pm0.10$	$1.04\pm0.07$	$0.40\pm0.06$	CORALIE
HD 217107	$5655\pm40$	$4.42\pm0.05$	$1.11\pm0.08$	$0.38\pm0.05$	FEROS
HD 217107(avg)	5660	4.42	1.01	0.39	-	$0.97\pm0.05$	Fischer et al. (1999)

The idea that planets and/or planetary material might be engulfed by a star is to some extent supported by the recent detection of ⁶Li in the planet host star HD 82943 (Israelian et al. 2001) - interpreted as a signal of the accretion of a planet during the history of the star - and probably by the detection of a significant difference in iron abundances in the very similar pair of dwarfs 16 Cyg A and 16 Cyg B, which also have very different Li contents (Laws & Gonzalez 2001; Gonzalez 1998).

Besides the [Fe/H] differences, there is currently some debate about possible anomalies concerning other elements (Paper I; Gonzalez et al. 2001; Smith et al. 2001). But the relatively low number of exoplanets known, and possible systematics with respect to the samples do not permit firm conclusions to be reached on the subject.

The observation that stars with planets are particularly metal-rich has so far been overshadowed by the restriction that in order to compare the metallicities of stars hosting planets with those of stars "without'' planets, authors had access only to published metallicity studies of volume-limited samples of dwarfs in the solar neighbourhood (mainly that of Favata et al. 1997, the alternative being to construct a sample using less precise metallicities using photometric indices). This is inconvenient for a number of reasons. First and most obviously, one cannot be sure if the sample used for comparison is really free from giant planets. Furthermore, the metallicities for the Favata et al. sample were determined using a much shorter line list for iron and different sources of atmospheric parameters (spectroscopic vs. colours) - see Paper I. This particular point may introduce systematic errors, and one might expect that the difference between the two samples was simply due to a bias related to the method used to compute the metallicities.

Table 3: Stars with giant planets or brown dwarf companions (bd) studied by other authors.
Star $T_{\rm eff}$ $\log{g}$ $\xi_t$ [Fe/H] Mass Reference Planet

(k) (cgs) (km s^-1) [ $M_{\odot}$ ] for spectroscopy discovery paper

HD 9826 6140 4.12 1.35 0.12 $1.28\pm0.02$ Gonzalez & Laws (2000) Butler et al. (1997)

HD 10697 5605 3.96 0.95 0.16 $1.10\pm0.01$ Gonzalez et al. (2001) Vogt et al. (2000)

HD 12661 5714 4.45 0.99 0.35 $1.01\pm0.02$ Gonzalez et al. (2001) Fisher et al. (2000)

HD 37124 5532 4.56 0.85 -0.41 - Gonzalez et al. (2001) Vogt et al. (2000)

HD 46375 5250 4.44 0.80 0.21 - Gonzalez et al. (2001) Marcy et al. (2000)

HD 75732A 5250 4.40 0.80 0.45 $1.05\pm0.03$ Gonzalez & Vanture (1998) Butler et al. (1997)

HD 80606 5645 4.50 0.81 0.43 $\sim$ 1.1 Naef et al. (2001b) Naef et al. (2001b)

HD 89744 6338 4.17 1.55 0.30 $1.55\pm0.03$ Gonzalez et al. (2001) Korzennik et al. (2000)

HD 92788 5775 4.45 1.00 0.31 $1.05\pm0.02$ Gonzalez et al. (2001) Queloz et al. (2001)

Fisher et al. (2000)

HD 95128 5800 4.25 1.0 0.01 $1.03\pm0.03$ Gonzalez (1998) Butler & Marcy (1996)

HD 114762 $^{\rm bd}$ 5950 4.45 1.0 -0.60 $0.82\pm0.03$ Gonzalez (1998) Latham et al. (1989)

HD 117176 5500 3.90 1.0 -0.03 $1.10\pm0.02$ Gonzalez (1998) Marcy & Butler (1996)

HD 120136 6420 4.18 1.25 0.32 $1.34\pm0.02$ Gonzalez & Laws (2000) Butler et al. (1997)

HD 130322 5410 4.47 0.95 0.05 $\sim$ 0.89 Gonzalez et al. (2001) Udry et al. (2000)

HD 134987 5715 4.33 1.00 0.32 1.02^+0.07 _-0.03 Gonzalez et al. (2001) Vogt et al. (2000)

HD 143761 5750 4.10 1.2 -0.29 $0.96\pm0.03$ Gonzalez (1998) Noyes et al. (1997)

HD 145675 5300 4.27 0.80 0.50 $\sim$ 1.05 Gonzalez et al. (1999) Udry et al (2001)

HD 168443 5555 4.10 0.90 0.10 $1.01\pm0.02$ Gonzalez et al. (2001) Marcy et al. (1999)

Udry et al. (2001)

HD 177830 4818 3.32 0.97 0.36 $1.03\pm0.11$ Gonzalez et al. (2001) Vogt et al. (2000)

HD 186427 5685 4.26 0.80 0.07 $0.97\pm0.03$ Laws & Gonzalez (2001) Cochran et al. (1997)

HD 187123 5830 4.40 1.00 0.16 $1.08\pm0.04$ Gonzalez et al. (1999) Butler et al (1998)

HD 192263 4964 4.49 0.95 -0.03 $\sim$ 0.80 Gonzalez et al. (2001) Santos et al. (2000b)

Vogt et al. (2000)

HD 209458 6063 4.38 1.02 0.04 $1.12\pm0.02$ Gonzalez et al. (2001) Mazeh et al. (2000)

Henry et al. (2000)

HD 217014 5795 4.41 1.05 0.21 $1.07\pm0.01$ Gonzalez et al. (2001) Mayor & Queloz (1995)

HD 222582 5735 4.26 0.95 0.02 $0.95\pm0.01$ Gonzalez et al. (2001) Vogt et al. (2000)

**Table 3:** Stars with giant planets or brown dwarf companions (bd) studied by other authors.
Star	$T_{\rm eff}$	$\log{g}$	$\xi_t$	[Fe/H]	Mass	Reference	Planet
	(k)	(cgs)	(km s^-1)		[ $M_{\odot}$ ]	for spectroscopy	discovery paper

HD 9826	6140	4.12	1.35	0.12	$1.28\pm0.02$	Gonzalez & Laws (2000)	Butler et al. (1997)
HD 10697	5605	3.96	0.95	0.16	$1.10\pm0.01$	Gonzalez et al. (2001)	Vogt et al. (2000)
HD 12661	5714	4.45	0.99	0.35	$1.01\pm0.02$	Gonzalez et al. (2001)	Fisher et al. (2000)
HD 37124	5532	4.56	0.85	-0.41	-	Gonzalez et al. (2001)	Vogt et al. (2000)
HD 46375	5250	4.44	0.80	0.21	-	Gonzalez et al. (2001)	Marcy et al. (2000)
HD 75732A	5250	4.40	0.80	0.45	$1.05\pm0.03$	Gonzalez & Vanture (1998)	Butler et al. (1997)
HD 80606	5645	4.50	0.81	0.43	$\sim$ 1.1	Naef et al. (2001b)	Naef et al. (2001b)
HD 89744	6338	4.17	1.55	0.30	$1.55\pm0.03$	Gonzalez et al. (2001)	Korzennik et al. (2000)
HD 92788	5775	4.45	1.00	0.31	$1.05\pm0.02$	Gonzalez et al. (2001)	Queloz et al. (2001)
							Fisher et al. (2000)
HD 95128	5800	4.25	1.0	0.01	$1.03\pm0.03$	Gonzalez (1998)	Butler & Marcy (1996)
HD 114762 $^{\rm bd}$	5950	4.45	1.0	-0.60	$0.82\pm0.03$	Gonzalez (1998)	Latham et al. (1989)
HD 117176	5500	3.90	1.0	-0.03	$1.10\pm0.02$	Gonzalez (1998)	Marcy & Butler (1996)
HD 120136	6420	4.18	1.25	0.32	$1.34\pm0.02$	Gonzalez & Laws (2000)	Butler et al. (1997)
HD 130322	5410	4.47	0.95	0.05	$\sim$ 0.89	Gonzalez et al. (2001)	Udry et al. (2000)
HD 134987	5715	4.33	1.00	0.32	1.02^+0.07 _-0.03	Gonzalez et al. (2001)	Vogt et al. (2000)
HD 143761	5750	4.10	1.2	-0.29	$0.96\pm0.03$	Gonzalez (1998)	Noyes et al. (1997)
HD 145675	5300	4.27	0.80	0.50	$\sim$ 1.05	Gonzalez et al. (1999)	Udry et al (2001)
HD 168443	5555	4.10	0.90	0.10	$1.01\pm0.02$	Gonzalez et al. (2001)	Marcy et al. (1999)
							Udry et al. (2001)
HD 177830	4818	3.32	0.97	0.36	$1.03\pm0.11$	Gonzalez et al. (2001)	Vogt et al. (2000)
HD 186427	5685	4.26	0.80	0.07	$0.97\pm0.03$	Laws & Gonzalez (2001)	Cochran et al. (1997)
HD 187123	5830	4.40	1.00	0.16	$1.08\pm0.04$	Gonzalez et al. (1999)	Butler et al (1998)
HD 192263	4964	4.49	0.95	-0.03	$\sim$ 0.80	Gonzalez et al. (2001)	Santos et al. (2000b)
							Vogt et al. (2000)
HD 209458	6063	4.38	1.02	0.04	$1.12\pm0.02$	Gonzalez et al. (2001)	Mazeh et al. (2000)
							Henry et al. (2000)
HD 217014	5795	4.41	1.05	0.21	$1.07\pm0.01$	Gonzalez et al. (2001)	Mayor & Queloz (1995)
HD 222582	5735	4.26	0.95	0.02	$0.95\pm0.01$	Gonzalez et al. (2001)	Vogt et al. (2000)

With the goal of settling the question about the high metallicity content of stars with planets, we present here a spectroscopic study of a volume-limited sample of 43 stars included in the CORALIE (Udry et al. 2000) planet search programme, and for which the radial velocities seem to be constant over a large time interval. The technique used, line lists and atmospheric models were those usually applied by most authors working on the metallicities of stars with planets (e.g. Paper I; Gonzalez et al. 2001). We show that the currently known stars with giant planets are on average more metal-rich than "field stars'', for which there is no radial-velocity signature of planets. Furthermore, the results are used to set strong constraints on the cause of the observed "anomaly'', significantly excluding the "pollution'' scenario. The impact on the planetary formation and evolutionary models is discussed.

1 Introduction