LMT Science Data Archive

The LMT Science Data Archive contains calibrated spectra, maps, and ancillary data from the facility spectral line and continuum instruments operating on the LMT.  At present, these instruments are the SEQUOIA (3mm spectral line receiver), MIPS1mm (1mm spectral line receiver), Redshift Search Receiver (RSR) and TolTEC (3 band continuum camera). Information about the receivers/camera and their data can be found on the instrumentation webpage and in the videos on this page. 

The Archive is searchable using the LMT Archive Search Tool. The Tool provides a variety of ways to search for and limit searches for data. For proposal teams, the easiest access method is to search on the Project ID, which will return all data for a project. Archival data users might find the RA/Dec cone search most useful. The Tool returns a list of all observations matching the search criteria; the user can select and download the observations of interest. 

The Tool uses the “*” character as a wild card for any text search field. For example, the string “*2024-S1-US-5*” in the Project ID box will return all observations for the project “2024-S1-US-5”, if no observation numbers (OBSNUM) or other parameters are set. The wild card can also be used in a Target Name. The Target Name must be an exact match (not case-sensitive) if no wildcard is present. Please be careful with wildcard usage as the list returned may be unusably long.

The Tool has explanations for each of the allowed search parameters. If any search box is blank, all values for that parameter are considered to match.

Data in the archive have a proprietary period of 1 year from the time of entry into the archive during which time they are only accessible to the PI and their team. The access is controlled by the API token which is distributed to the PI in email by the LMT Help Desk. All data beyond the propriety period can be accessed and downloaded by anyone; no API token is needed.

If you have questions about the data please contact the LMT Help Desk: lmthelpdesk@umass.edu.

Spectral Line Data

The data for the SEQUOIA, RSR, and MSIP1mm receivers have multiple versions of the data for each observation number, representing different processing levels. Processing level 1 is the default automatic, minimal-flagging pipeline processing of the data which is available to the PI team 1-2 days after the data are taken. Processing level 2 is the approved processing by the data analysts; a grade is assigned to the data associated with level 2. Processing level 3 is the combination of relevant observations of an object or mapped region into a single data set. If the total data for an object consists of only one observation number (one observation) there will be no Level 3 data. Videos describing the data products are here.

The Search Tool returns the observations and combination of observations that match the selection criteria. The Search Results page allows you to download the Science Ready Science Products (SRDPs) or the Single Dish FITS product. The SRDPs contain the Timely Analysis Products (TAPs), FITS cubes and other ancillary files; the README file in this data folder describes each relevant file within the dataset. The SDFITS file contains calibrated spectra in the form of binary SDFITS data (or netCDF).

All spectral line data are in units of TA* , with no correction for telescope efficiency applied.

TolTEC Data Coming Soon

TolTEC data will be placed in the LMT Archive as it becomes available.

Acknowledgement Data from the LMT

The observatory asks that you please include the following acknowledgement in papers that use LMT data:

" This work would not have been possible without the long-term financial support from the Mexican Humanities, Science and Technology Funding Agency, CONAHCYT (Consejo Nacional de Humanidades, Ciencias y Tecnologías), and the US National Science Foundation (NSF), as well as the Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE) and the University of Massachusetts, Amherst (UMass). The operation of the LMT is currently funded by CONAHCYT grant #297324 and NSF grant #2034318. "

For publications based on LMT observations, including archival data, we request that authors also include the scientific project ID (e.g. 2023-S1-MX-46) as in the following statement:

" The data described in this paper include LMT observations conducted under the scientific program YEAR-SEMESTER-COUNTRY-NUMBER (see example above). The authors acknowledge the scientific and technical support of the LMT staff during the observations and generation of data products provided to the authors. "