{
  "$schema": "./item.schema.json",
  "id": "pal5-gaia-dr2",
  "type": "publication",
  "cvs": [
    "np",
    "2page"
  ],
  "date": {
    "start": "2020-02"
  },
  "title": "An extended Pal 5 stream in Gaia DR2",
  "shortTitle": "An Extended Pal 5 Stream in Gaia DR2",
  "nickTitle": "Extended Pal 5",
  "status": "published",
  "entryType": "article",
  "authors": [
    {
      "family": "Starkman",
      "given": "Nathaniel",
      "me": true,
      "orcid": "0000-0003-3954-3291"
    },
    {
      "family": "Bovy",
      "given": "Jo",
      "orcid": "0000-0001-6855-442X",
      "affiliation": "Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, Ontario M5S 3H4, Canada"
    },
    {
      "family": "Webb",
      "given": "Jeremy",
      "orcid": "0000-0003-3613-0854",
      "affiliation": "Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, Ontario M5S 3H4, Canada"
    }
  ],
  "venue": {
    "journal": "Monthly Notices of the Royal Astronomical Society"
  },
  "arxiv": "1909.03048",
  "doi": "10.1093/mnras/staa534",
  "links": [
    {
      "rel": "paper",
      "url": "https://doi.org/10.1093/mnras/staa534"
    },
    {
      "rel": "data",
      "url": "https://zenodo.org/record/7273032"
    }
  ],
  "tags": [
    "streams",
    "milky-way",
    "dynamics"
  ],
  "citekey": "Starkman+:2020:pal5-gaia-dr2",
  "abstract": "We present the results of a detailed search for members of the Pal 5 tidal tail system in Gaia Data Release 2 (DR2). Tidal tails provide a sensitive method for measuring the current and past gravitational potential of their host galaxy as well as for testing predictions for the abundance of dark matter subhaloes. The Pal 5 globular cluster and its associated tails are an excellent candidate for such analysis; however, only ∼23° of arc are currently known, with in particular the leading tail much shorter than the trailing. Using Gaia DR2 and its precise astrometry, we extend the known extent of the Pal 5 tail to ∼30°, 7° of which are newly detected along the leading arm. The detected leading and trailing arms are symmetric in length and remain near constant width. This detection constrains proposed models in which the Galactic bar truncates Pal 5’s leading arm. Follow-up spectroscopic observations are necessary to verify the candidate stream stars are consistent with the known tidal tails. If confirmed, this Pal 5 stream extension opens up new possibilities to constrain the Galactic potential.",
  "highlight": {
    "topic": "galactic",
    "image": "highlights/pal5-gaia-dr2.webp",
    "alt": "Smoothed density map of Gaia DR2 stars around the Palomar 5 globular cluster, in coordinates aligned with its tidal tails. A dark band marks the stream detected in earlier CFHT data, mostly the trailing arm; black dots trace the tails found here, matching that band and continuing about 7 degrees further along the leading arm.",
    "description": "Palomar 5 is a star cluster being pulled apart by the Milky Way, leaving two tails of stars that trace the Galaxy’s gravity. Gaia data show its leading tail runs about 7° further than was known, making the stream about 30° long. The two tails come out roughly equal, which limits how much the Galactic bar can have cut one short."
  }
}