摘要：Context. Void population consists mainly of late-type and low surface
brightness (LSB) dwarf galaxies, whose atomic hydrogen is the main component of their
baryonic matter. Therefore observations of void galaxy Hi are mandatory to
understand both their evolution and dynamics.
Aims. Our aim was to obtain integrated Hi parameters for a
fainter part of the nearby Lynx-Cancer void galaxy sample (total of 45 objects) with the
Nançay Radio Telescope (NRT) and to conduct the comparative analysis of the whole 103 void
galaxies with known Hi data with a sample of similar galaxies residing in denser
environments of the Local Volume.
Methods. For Hi observations we used the NRT with its sensitive
antenna/receiver system FORT and standard processing. The comparison of the void and
“control” samples on the parameter M(HI)/LB is conducted with the non-parametric
method “The 2 × 2 Contingency
Table test”.
Results. We obtained new Hi data for about 40% of the
Lynx-Cancer galaxy sample. Along with data from the literature, we use for further
analysis data for 103 void objects. The proxy of the evolutional parameter M(HI)/LB of the void
sample is compared with that of 82 galaxies of morphological types 8–10 residing in the
Local Volume groups and aggregates.
Conclusions. At the confidence level of P = 0.988, we conclude that
for the same luminosity, these void galaxies are systematically gas-richer, in average by
~39%. This result is
consistent with the authors’ earlier conclusion on the smaller gas metallicities and
evidences for the slower low-mass galaxy evolution in voids.
关键词：galaxies: dwarf;galaxies: evolution;galaxies: distances and redshifts;large-scale structure of Universe;radio lines: galaxies
