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COS Data Handbook 2.00
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COS Data Handbook > Chapter 2: COS Data Files > 2.5 Data Storage Requirements

2.5
Users are reminded to consider the large size of counts and flt files when allocating disk space for storing and reprocessing COS data. Additionally, corrtag files with a large number of events can be quite large. These images serve as intermediate or final calibration products from the pipeline and have the file sizes given in Megabytes in Table 2.13. Note, that these sizes are per exposure, and an associated observation set may have several exposures.
Table 2.13: COS Pipeline Data Volumes per Exposure
9 bytes per photon (18MB per BUFFER-TIME)
8 bytes per photon (16 MB per BUFFER-TIME
35 bytes per photon (70 MB per BUFFER-TIME)
26 bytes per photon (52 MB per BUFFER-TIME)
0.5MB1
1MB2

1
Values pertain to x1d_a or x1d_b files only. These files are temporary output products from calcos processing

2
Values are in addition to amounts given for each segment.

Similarly, users are reminded of the large cumulative size of calibrated COS spectroscopic datasets. Table 2.14 provides volume estimates for calibrated COS datasets.
Table 2.14: COS Pipeline Data Volumes per Calibrated Exposure
Pipeline-processed volume per exposure

1
Minimum volume delivery option over the internet

2
Approximately 70 MB per BUFFER-TIME

3
Approximately 52 MB per BUFFER-TIME


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