Sample Data Files

Introduction

I have been asked over time for samples of the Vela data recorded daily. In the past I have responded individually to such requests. Due to the large size of such data files the response has often been in the form of exchanging USB drives.

In recent times the available internet quotas and download speeds have increased markedly and - following comments by a member of the NSG - I will attempt to provide such data online.

The data will initially be just two example samples of Vela observation data - accompanied with supplementary information required to process the data and also example analysis results.

The two example samples chosen are from observations taken at MJD 59022.1660 and MJD 59029.1469 - returning PDMP SNRs of 16 and 13 respectively.

NOTES: Active links are not provided - so the DropBox links will be needed to be 'cut-and-pasted'. Consideration will also be given to providing one raw IQ file (17 GB) - but it is unknown at this stage as to whether this is practical or not.

Instructions for PRESTO Processing

The link to a top folder containing a PDF containing instructions for the processing by PRESTO of the filterbank data files is here...

https://www.dropbox.com/sh/n0590abzy5t0ioa/AAAkqYYPiqfL7kX14TyKzZRWa?dl=0

Following this link will show the PDF as well as two folders named 'SNR16' and 'SNR13' linked individually below.

Important: Read the PDF first to get an overview of the results below.

Sample #1 - MJD 59022.1660 - PDMP SNR = 16

In the link below will be found seven files...

  1. rtl_590221660.txt - supplementary information - required to analyse data

  2. rtl_590221660.ar - archive format file (16 MB)

  3. rtl_590221660_pdmp.png - image of the output result of PDMP

  4. rtl_590221660.fil - filterbank format file (1.7 GB)

  5. rtl_590221660_fil.png - image of the output result of PREPFOLD working on the 'fil' file. This shows the effect of RFI where the real pulse is contaminated by several RFI bursts.

  6. rtl_590221660_ic18_19_28_fil.png - image of the output result of PREPFOLD working on the 'fil' file again - but this time using the 'ignorechan' option. This shows the improvement to be made with RFI excision.

  7. rtl_590221660_vcp.png - image of the output result of VCP (HawkRAO daily observation software)

Link to DropBox folder containing the above (cut-and-paste link)...

https://www.dropbox.com/sh/gpi7prfrsu5wv10/AACMhIrG7sSaj5sXnXdrvrpBa?dl=0

Sample #2 - MJD 59029.1469 - PDMP SNR = 13

In the link below will be found six files...

  1. rtl_590291469.txt - supplementary information - required to analyse data

  2. rtl_590291469.ar - archive format file (16 MB)

  3. rtl_590291469_pdmp.png - image of the output result of PDMP

  4. rtl_590291469.fil - filterbank format file (1.7 GB)

  5. rtl_590221660_fil.png - image of the output result of PREPFOLD working on the 'fil' file. This shows mild RFI and so using the 'ignorechan' option would gain little improvement.

  6. rtl_590291469_vcp.png - image of the output result of VCP (HawkRAO daily observation software)

Link to DropBox folder containing the above (cut-and-paste link)...

https://www.dropbox.com/sh/h01g9ain1o3hz74/AAARgeQwCtM6hoQDBr5RSXi6a?dl=0