Developer docs

To consume LXCat data by another program, the LXCat web service provides several API endpoints.

• Developer docs
  • Authorize and authenticate
  • Fetch particle states
  • Fetch cross section sets
    • Filtering
    • Paging
  • Fetch cross section set
  • Fetch cross sections
    • Paging
  • Fetch a cross section
  • Fetch multiple cross sections

Authorize and authenticate

The API endpoints of the LXcat web service require authorization and authentication.

You can get authorized by mailing info@lxcat.net. Send the mail from the same email you used to login to LXCat.

Authentication is done using a JWT token. The token can be generated and copied from the /developer page.

Use Authorization: Bearer <token> as header in all of the HTTP requests. For example, using curl:

curl -H "Authorization: Bearer <token>" https://example.url.net

Fetch particle states

To retrieve states of particle Ar use:

export FILTER=$(echo '{"particle": {"Ar": { "charge": {}}}}' | base64)
curl https://nl.lxcat.net/api/states?filter=$FILTER

The filter value is JSON object which base64 encoded, because it is nested and contains URL un-friendly characters.

This will return something like

{
  "433590": {
    "charge": 0,
    "id": "Ar",
    "particle": "Ar"
  },
  "433593": {
    "charge": 0,
    "electronic": [
      {
        "scheme": "LS",
        "config": [],
        "term": {
          "L": 0,
          "S": 0,
          "P": 1,
          "J": 0
        },
        "summary": "^1S_0"
      }
    ],
    "id": "Ar{^1S_0}",
    "particle": "Ar",
    "type": "AtomLS"
  }
}

The filter search param must be a subset of what you get back from

curl https://nl.lxcat.net/api/states/choices

Fetch cross section sets

To fetch first page of cross section sets use

curl https://nl.lxcat.net/api/scat-css

{
  "items: [
    {
      "id": "421901",
      "name": "Some name"
    },
    {
      "id": "421942",
      "name": "Some other name"
    }
  ]
}

Filtering

The sets can be filtered on 3 facets: species, contributor, tag.

The cross section sets can be filtered on which species of particle occur in any of their cross sections by using the species search param. The species search param value uses the same format as the state filter.

The contributor search param will filter on contributing organization. To retrieve all sets either contributed by Some org or Other org use:

curl https://nl.lxcat.net/api/scat-css?contributor=Some+org&contributor=Other+org

Cross section sets can be filtered on reaction type tag by using the tag search param. For example to only get sets which have a cross section with a rotational reaction use

curl https://nl.lxcat.net/api/scat-css?tag=Rotational

Another way to get the filter you want is to go to https://nl.lxcat.net//scat-css, apply some filters and copy all the search params (stuff after ? in the adress bar) to https://nl.lxcat.net/api/scat-css?<search params from web page>.

Paging

The offset and count search param can be used for paging.

For example to list sets 1,2,3 use

curl https://nl.lxcat.net/api/scat-css?offset=1&count=3

Fetch cross section set

To fetch a single cross section set use the id property found in fetch cross section sets query.

To fetch in JSON format use

curl https://nl.lxcat.net/api/scat-css/<id of set>

The style of the reference can be changed using refstyle search param. Valid choices are csl (default), apa and bibtex.

For example

curl https://nl.lxcat.net/api/scat-css/<id of set>?refstyle=apa

To fetch in Bolsig+ format use

curl https://nl.lxcat.net/api/scat-css/<id of set>/legacy

This API endpoint requires authentication.

Fetch cross sections

Cross section headers can be fetched at https://nl.lxcat.net/api/scat-cs URL, this will return nothing as it requires search parameters.

The search parameters can be found on the Cross sections search page. Copy all the search params (stuff after ? in the adress bar) to https://nl.lxcat.net/api/scat-cs?<search params from web page>. For example select Ionization as a reaction type tag then the search params are reactions=%5B%7B"consumes"%3A%5B%7B%7D%5D%2C"produces"%3A%5B%7B%7D%5D%2C"typeTags"%3A%5B"Ionization"%5D%2C"reversible"%3A"both"%2C"set"%3A%5B%5D%7D%5D. To do an API call

curl  'https://nl.lxcat.net/api/scat-cs?reactions=%5B%7B"consumes"%3A%5B%7B%7D%5D%2C"produces"%3A%5B%7B%7D%5D%2C"typeTags"%3A%5B"Ionization"%5D%2C"reversible"%3A"both"%2C"set"%3A%5B%5D%7D%5D'

THis will return something like:

[
  {
    "id": "132336",
    "reaction": {
      "reversible": false,
      "type_tags": [
        "Ionization"
      ],
      "rhs": [{...}],
      "lhs": [{...}],
    },
    "reference: [{...}],
    "isPartOf": [
      "N2"
    ]
  },
  ...
]

The id can be used to fetch the data of the cross section.

Paging

The offset and count search param can be used for paging.

For example to list sections 1,2,3 use

curl https://nl.lxcat.net/api/scat-cs?offset=1&count=3&<other search params>

Fetch a cross section

To fetch in JSON format use

curl https://nl.lxcat.net/api/scat-cs/<id of section>

This API endpoint requires authentication.

Fetch multiple cross sections

To fetch in JSON format use

curl https://nl.lxcat.net/api/scat-cs/bag?ids=<id of section1>,<id of section2>