SDSS colour fit parameters

The bimodal galaxy color distribution: Dependence on luminosity and environment

Fit parameters to the SDSS colour distribution

Link to Michael Balogh's Home Page
Link to Ivan Baldry's home page

Here we provide the parameters of the double-Gaussian model fit to the SDSS colour distribution in Balogh et al. (2004). These fits are applicable to the model magnitudes of colours in the SDSS DR1 data, with appropriate corrections for Galactic extinction and the k-corrections of Blanton et al. (2003).

Mr is absolute r-band luminosity assuming matter density=0.3, dark energy density=0.7, and Hubble constant=70 km/s/Mpc.
The densities are base-10 logarithms of the projected galaxy number density, computed from the distance to the fifth-nearest neighbour brighter than Mr=-20, and with a velocity within 1000 km/s.
Numbers in parenthesis are 1-sigma uncertainties. Standard deviations are fixed as a function of luminosity.

An ascii version of the table can be found here

Mr range	Density range	No. galaxies	chi sq. per d.o.f.	Blue			Red
Mr range	Density range	No. galaxies	chi sq. per d.o.f.	Amplitude	Mean	Standard Deviation	Amplitude	Mean	Standard Deviation
-23 -> -22	-2.000 -> -0.748	126	0.533	10.250 (1.846)	2.173 (0.061)	0.302	18.971 (4.925)	2.436 (0.023)	0.090
	-0.748 -> -0.285	386	0.647	24.809 (2.706)	2.184 (0.037)	0.302	83.316 (8.646)	2.473 (0.009)	0.090
	-0.285 -> 0.145	434	0.949	24.492 (2.786)	2.208 (0.039)	0.302	102.662 (9.293)	2.480 (0.008)	0.090
	0.145 -> 0.812	487	0.535	20.911 (2.744)	2.258 (0.044)	0.302	142.520 (10.353)	2.498 (0.006)	0.090
	0.812 -> 3.000	292	0.290	7.041 (1.803)	2.207 (0.096)	0.302	104.388 (8.267)	2.511 (0.007)	0.090
-22 -> -21	-2.000 -> -0.748	767	0.755	55.655 (3.198)	1.960 (0.025)	0.354	108.641 (9.388)	2.404 (0.009)	0.096
	-0.748 -> -0.285	1573	0.673	110.267 (4.568)	1.972 (0.018)	0.354	243.139 (13.845)	2.428 (0.006)	0.096
	-0.285 -> 0.145	1558	0.801	99.888 (4.474)	2.011 (0.020)	0.354	272.690 (14.409)	2.448 (0.005)	0.096
	0.145 -> 0.812	1604	0.551	82.338 (4.427)	2.073 (0.023)	0.354	355.716 (16.052)	2.445 (0.004)	0.096
	0.812 -> 3.000	799	0.339	28.138 (2.750)	2.104 (0.041)	0.354	224.772 (11.868)	2.465 (0.005)	0.096
-21 -> -20	-2.000 -> -0.748	1325	1.472	118.647 (4.317)	1.610 (0.013)	0.308	113.868 (6.856)	2.335 (0.009)	0.132
	-0.748 -> -0.285	2531	1.829	218.354 (6.021)	1.631 (0.011)	0.308	237.453 (10.075)	2.340 (0.006)	0.132
	-0.285 -> 0.145	2416	1.508	195.983 (5.772)	1.659 (0.011)	0.308	258.558 (10.451)	2.347 (0.006)	0.132
	0.145 -> 0.812	2456	1.454	162.007 (5.524)	1.727 (0.014)	0.308	346.582 (12.123)	2.359 (0.005)	0.132
	0.812 -> 3.000	1153	0.995	42.732 (2.925)	1.730 (0.028)	0.308	240.760 (9.327)	2.374 (0.005)	0.132
-20 -> -19	-2.000 -> -0.748	614	0.866	68.417 (3.247)	1.435 (0.015)	0.295	21.910 (2.997)	2.253 (0.025)	0.151
	-0.748 -> -0.285	1136	1.155	119.293 (4.343)	1.468 (0.013)	0.295	56.647 (4.758)	2.217 (0.015)	0.151
	-0.285 -> 0.145	1106	1.151	111.754 (4.174)	1.470 (0.013)	0.295	63.671 (4.792)	2.264 (0.014)	0.151
	0.145 -> 0.812	1008	0.410	84.640 (3.767)	1.555 (0.016)	0.295	97.013 (5.865)	2.266 (0.011)	0.151
	0.812 -> 3.000	557	1.088	23.981 (2.110)	1.558 (0.033)	0.295	93.272 (5.358)	2.297 (0.009)	0.151
-19 -> -18	-2.000 -> -0.748	128	0.688	14.822 (1.624)	1.288 (0.034)	0.287	2.363 (1.193)	2.227 (0.110)	0.166
	-0.748 -> -0.285	273	0.705	32.591 (2.283)	1.326 (0.023)	0.287	4.299 (1.477)	2.195 (0.077)	0.166
	-0.285 -> 0.145	410	0.890	43.414 (2.645)	1.400 (0.020)	0.287	17.010 (2.455)	2.202 (0.031)	0.166
	0.145 -> 0.812	356	0.762	33.070 (2.400)	1.456 (0.025)	0.287	22.799 (2.879)	2.188 (0.024)	0.166
	0.812 -> 3.000	155	0.326	6.286 (1.226)	1.514 (0.080)	0.287	23.756 (2.697)	2.246 (0.022)	0.166