**Table 3:** Best-fit parameters of the GRB 000911 afterglow light curve in the *BVRIJ* bands, computed assuming a power law decay plus a constant (host galaxy) contribution with and without the presence of an underlying 1998bw-like SN occurring simultaneously with the GRB. Host galaxy magnitudes reported here are not corrected for Galactic reddening. Values within brackets are fixed in the corresponding fit.
Filter	$\alpha$	Host galaxy magnitude	SN intensity^a	$\chi^2$ /d.o.f.
Fits without SN plus free $\alpha$
B	$1.12 \pm 0.17$	[26.1]	-	4.2/4
V	$1.63 \pm 0.05$	[25.4]	-	7.3/7
R	$1.45 \pm 0.03$	[25.27]	-	7.4/11
I	$1.43 \pm 0.06$	[24.3]	-	12.6/12
J	$0.79 \pm 0.15$	[23.6]	-	7.9/3
Fits without SN plus fixed $\alpha$
B	[1.48]	[26.1]	-	8.3/5
V	[1.48]	[25.4]	-	14.0/8
R	[1.48]	[25.27]	-	8.4/12
I	[1.48]	[24.3]	-	13.2/13
J	[1.48]	[23.6]	-	28.4/4
Fits with SN1998bw plus fixed $\alpha$
R	[1.48]	[25.27]	$3.5 \pm 2.0$	5.8/11
I	[1.48]	[24.3]	$3.4 \pm 1.7$	8.8/12
J	[1.48]	[23.6]	$0.9 \pm 0.3$	3.6/3

^a Ratio between the SN 1998bw light peak and that of the best-fit SN.

	1 Introduction
	2 Observations and data reduction
	3 Results
	4 Discussion
	5 Conclusions
	References