Parkes observations for project P1372 semester 2025OCTS_03

The gamma-ray source, 4GFL J1646.5-4406, has recently been identified as a new spider pulsar binary, and potentially a redback system due to its longer eclipse. With only ~30 redback systems known so far, a detailed analysis of such a new system is needed to further understand this population. We requested simultaneous 6x2-hour Murriyang UWL and 6x3-hour ATCA L-band observations on this newly identified pulsar, PSR J1646-4406, covering its ingress and/or egress to further constrain its orbital parameters, investigate the eclipse mechanism and intrabinary shocks, and understand its evolutionary pathways.