Multiband photometry of rich abell clusters: constraints on the dwarf star content of dark matter
نویسندگان
چکیده
We present results of large-aperture (D1@) JK photometry and CCD BV RI photometry near the centers of three distant (0.111 z1 0.22), rich Abell clusters of galaxies. The colors of the integrated light are consistent with those of nearby E and S0 galaxies. The absence of anomalous reddening implies that no more than 2 h~1% (1 p limit) of the dark matter in these clusters can be in the form of low-mass (D0.1 subdwarfs or old disk dwarfs. The limit increases to 3 h~1% if expressed in terms of zeroM _ ) metallicity dwarfs. These results constrain the mass function of baryonic objects which might contribute to the dark matter. Subject headings : dark matter È galaxies : clusters : general È galaxies : photometry È galaxies : stellar content È stars : late-type
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