The Fourth HAWC Catalog of Very-High-Energy Gamma-Ray Sources

We present an updated catalog of TeV gamma-ray sources using data from the 5th reconstruction pass of data from the High Altitude Water Cherenkov Observatory (HAWC). In addition to improved reconstruction and nearly three years of additional data, this new catalog uses a systematic multi-source fitting procedure to model the data with much greater flexibility and accuracy. Besides including more varied modeling of source morphology and spectral shape than previous HAWC catalogs, this catalog uses a robust modeling of galactic diffuse TeV emission through the HERMES package. This catalog reports 85 sources with a Test Statistic greater than 25, including 11 sources not associated with any TevCat source using a distance-based association criterion. Additionally, there are 12 sources not associated with any physical counterpart in Low or High Mass X-ray Binary, the ATNF or Fermi-LAT pulsar, or SNR catalogs of sources. Five of the aforementioned sources have no counterpart in any of the catalogs searched and represent new sources of considerable interest.