Differences
This shows you the differences between two versions of the page.
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pulsarinstruments:psrix_psrix2:psrix:index [2019/09/17 17:38] ramesh |
pulsarinstruments:psrix_psrix2:psrix:index [2019/09/17 17:42] (current) ramesh |
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| | Timing |16c16i1024s| 800 |25/200| | | Timing |16c16i1024s| 800 |25/200| | ||
| | LEAP |32c32i1024s| 1024 |16/128| | | LEAP |32c32i1024s| 1024 |16/128| | ||
| - | | FilerBank |32c32i1024s|1000|15.625/500| | + | | FilterBank |32c32i1024s|1000|15.625/500| |
| Realtime coherent dedispersion/folding and/or baseband recording is possible in all of the three settings. Depending on the type of observations, various sections of the cluster are active. | Realtime coherent dedispersion/folding and/or baseband recording is possible in all of the three settings. Depending on the type of observations, various sections of the cluster are active. | ||
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| **Codeix blade system**: The unit consists of 8x high performance blades and used as a stand-by for the automatix timing mode. | **Codeix blade system**: The unit consists of 8x high performance blades and used as a stand-by for the automatix timing mode. | ||
| - | Please click the links below for detailed information | ||
| - | - [[pulsarinstruments:psrix_psrix2:psrix:modes|Instrument modes]] | + | |
| + | === PSRIX Instrument Modes === | ||
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| + | == Baseband mode == | ||
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| + | This is most flexible mode of the instrument, and uses the most disk space. Depending on the firmware and sampling rate, each node receives either 64MB/s, 100MB/s or 125MB/s data streams, that is recorded to the disk. This data processed offline depending on the scientific need. The data can now be folded with a give number of bins, converted to pulsar search data or searched for giant pulses from a known pulsar. | ||
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| + | For known pulsars, DSPSR is used to coherently dedisperse and average over a given time, write out all single pulses, or search for pulses that only have a specified signal-to-noise ratio. The last technique is used to search for giant pulses from fast spinning pulsars like Crab or B1937+21. In the post processing stage, single pulses from all sub-bands can be combined using PSRCHIVE. | ||
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| + | == Single pulse dump mode == | ||
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| + | For pulsars with spin period greater then 300ms, the signal can coherently dedispersed (number of channels depend on the DM of the pulsar), and the single pulses can be written out with full polarisation information and with a predefined number of phase-bins. One file per single pulse is created on disk. Usually the observation length is adjusted such that the number of files in a directory is ~10000. | ||
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| + | == Realtime folding mode == | ||
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| + | Among the three modes, this is the least flexible and consumes the least amount of disk space. In this case, the pulsar signal is coherently dedispersed and averaged over 10 seconds. One file every 10 seconds is written to disk, and can have all four Stokes parameters. The number of frequency channels depends on the DM of the pulsar. | ||
| == Old information == | == Old information == | ||
