The Void Phenomenon Revisited

TL;DR

This paper investigates the Void Phenomenon, highlighting the discrepancy between observed dwarf halos in cosmic voids and CDM predictions, and explores the potential of HI emission detection through ALFALFA survey data.

Contribution

It presents preliminary results suggesting possible detection of low-mass dwarf systems in cosmic voids via HI emission, offering new insights into the Void Phenomenon.

Findings

Preliminary ALFALFA survey results indicate potential detection of dwarf systems.

The study discusses the challenges in detecting field dwarf halos with halo masses < 10^9 solar.

It reviews recent work on the Void Phenomenon and detection prospects.

Abstract

The Void Phenomenon consists in the apparent discrepancy between the number of observed dwarf halos in cosmic voids and that expected from CDM simulations. We approach the problem considering the challenging prospects of detecting field dwarf systems with halo masses < 10^9 solar, via their possible HI emission. A brief review of recent work is followed by preliminary results from the ALFALFA survey, which suggest the possibility, but not yet the proof, that such objects may have been already detected towards the outskirts of the Local Group.