{
  "id": "J/ApJS/179/195",
  "title_cds": "A catalog of outer ejecta knots in Cas A",
  "title_create": "Hammell+, 2008",
  "year": "2008",
  "author": "Hammell M.C., Fesen R.A.",
  "title_pub": " A catalog of outer ejecta knots in the Cassiopeia A supernova remnant.",
  "first_author": "Hammell M.C.",
  "bibcode": [
    "2008ApJS..179..195H"
  ],
  "ref_biblio": [
    "<Astrophys. J. Suppl. Ser., 179, 195-208 (2008)>"
  ],
  "keyword_cds": [
    "Interstellar medium",
    "Supernova remnants",
    "Photometry, HST"
  ],
  "keyword_pub": "ISM: individual (Cassiopeia A) - ISM: kinematics and dynamics supernova remnants",
  "abstract": [
    "Hubble Space Telescope images of the core-collapse supernova remnant",
    "Cassiopeia A are used to identify high-velocity knots of ejecta",
    "located outside the remnant's main emission shell of expanding debris.",
    "These ejecta fragments are found near or ahead of the remnant's",
    "forward shock front and mostly lie from 120\" to 300\" in radial",
    "distance from the remnant's center of expansion. Filter flux ratios",
    "when correlated with published spectra show that these knots can be",
    "divided into three emission classes: (1) knots dominated by [NII]",
    "{lambda}6548,{lambda}6583 emissions, (2) knots dominated by [OII]",
    "{lambda}7319, {lambda}7330 emissions, and (3) knots displaying filter",
    "flux ratios suggestive of [SII], [OII], and [ArIII] {lambda}7135",
    "emission line strengths similar to the \"fast-moving knots\" (FMKs)",
    "found in the remnant's bright main shell. Of 1825 knots identified,",
    "444 are strong [NII] emission knots, 192 are strong [OII] emission",
    "knots, and 1189 are FMK-like knots. In terms of location around the",
    "remnant, 972, 207, and 646 knots are found in the remnant's northeast",
    "jet, southwest jet, and non-jet regions, respectively. Assuming a",
    "distance of 3.4kpc, derived knot transverse velocities based on proper",
    "motion measurements spanning a 9 month interval indicate maximum",
    "transverse expansion velocities for these three knot classes of 14500,",
    "13500, and 11500km/s, respectively. We present a catalog of these",
    "outlying ejecta clumps comprising finding charts, epoch 2004.2 knot",
    "positions, proper motions, photometric filter fluxes, and estimated",
    "knot emission type, along with cross-references to previous knot",
    "identifications and data. This compilation represents a nearly tenfold",
    "increase in the number of outlying, high-velocity ejecta knots",
    "identified around the Cassiopeia A remnant."
  ],
  "description": [
    "High-resolution, multiband images of the Cas A remnant were obtained",
    "on 2004 March 4-6 and December 4-5 using the Wide Field Channel (WFC)",
    "of the Advanced Camera for Surveys (ACS) on board the Hubble Space",
    "Telescope (HST)."
  ],
  "curator": "Greg Schwarz [AAS], Emmanuelle Perret [CDS]",
  "history": [
    "From electronic version of the journal"
  ],
  "see_also": [
    "B/hst : HST Archived Exposures Catalog (STScI, 2007)",
    "J/ApJ/456/234 : Cas A radio knots spectral indices (Anderson+ 1996)",
    "J/ApJ/613/343 : Cas A knot and filament proper motions (Delaney+, 2004)",
    "J/A+A/484/755 : Oxygen recombination lines from Cas A knots (Docenko+, 2008)",
    "J/ApJS/174/379 : Optical imaging and spectra of 3C 58 (Fesen+, 2008)"
  ],
  "tables": [
    {
      "name": "table2.dat",
      "desc": "Catalog of outlying ejecta knots in Cas A"
    }
  ],
  "archive_date_creation": "01-Oct-2009",
  "authors_details": [
    {
      "name": "Hammell, Molly C.",
      "affiliations": [
        "Department of Physics and Astronomy, 6127 Wilder Lab, Dartmouth College, Hanover, NH 03755"
      ]
    },
    {
      "name": "Fesen, Robert A.",
      "affiliations": [
        "Department of Physics and Astronomy, 6127 Wilder Lab, Dartmouth College, Hanover, NH 03755"
      ]
    }
  ],
  "catid": 21790195,
  "vizier_date_update": "20-Oct-2009",
  "xmatch": "J/ApJS/179/195/table2",
  "doi_pub": [
    "10.1086/591528"
  ],
  "doi_cds": "10.26093/cds/vizier.21790195",
  "alias": "[HF2008]",
  "type": [
    "OC"
  ],
  "archive_date_update": "24-Oct-2022",
  "uat": [
    "Interstellar medium",
    "Supernova remnants",
    "HST photometry"
  ],
  "ip_addr": "216.73.217.7",
  "data_access": "v-f"
}