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Release of a new installment of Science Verification data

Dec 07, 2016

A new installment of Science Verification data is available. This release contains data on the following Science Verification target:
• Arp 220 spectral line observations in Band 5 (H2O, CS, HNC) with the 12-m Array
• SgrB2(N) spectral scan observations across most of the Band 5 tuning range with an hybrid 12m-7m array
• VY CMa spectral line polarization observations of SiO and water lines in Band 5 with the 12m array

Details of the targets are listed on the Science Verification page.

The Science Verification data sets are available through the ALMA Science Portal. The following data products are available:
• Raw, uncalibrated data to allow users to try their hands at a complete data reduction process.
• Calibrated uv-data, allowing users to perform data analysis and post-processing.
• Reference images generated from the full reduction of the above data sets.
• Calibration and imaging data reduction scripts are provided as suggestions for data reduction. Following the provided examples will produce the calibrated data and/or reference images provided. A user may wish to perform a complete reduction starting from the raw data, for example to try their hands at a complete data reduction process. Or, a user may, for example, wish to execute only the imaging script to try different parameters.
• README file containing a summary of the data and data products, plus any other important information
• The VY CMa dataset contains the additional file VYCMa_Band5_PolCalibrationInformation.pdf with detailed notes of the polarization calibration

We hope that you will find that the quality of these datasets is impressive, but please remember that ALMA Science Verification data is taken as part of Extension and Optimization of Capabilities (EOC), and we are continuously testing new observing modes. These observations are made using a limited number of antenna elements, in non ideal configurations, new equipment and software and thus may contain more idiosyncrasies than data released to PIs in Early Science.

We thank the large number of staff at the JAO and the EU ARC Network who have participated in the EOC and Science Verification activities, observations and data reduction that made this release possible.

Reminder: In order to reduce and/or analyze the ALMA data, users need to use the Common Astronomy Software Applications (CASA) package. The CASA package can be accessed through http://casa.nrao.edu. Feedback on the data and on the CASA software is always welcome!