pulsar_finding
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Pulsar Finding
Using Presto, installed on chan1x
Links
B0329+54 May 05, 2018
In /home/sonata/B0329+54/may5
readfile /data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil
Assuming the data is a SIGPROC filterbank file.
1: From the SIGPROC filterbank file '/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil':
Telescope = ATA
Source Name = psrB0329+54
Backend = Unknown
Obs Date String = 2018-05-05T17:03:50
MJD start time = 58243.71099537036935
RA J2000 = 03:32:59.3672
RA J2000 (deg) = 53.24736328125
Dec J2000 = 54:34:43.5625
Dec J2000 (deg) = 54.5787673611111
Tracking? = True
Azimuth (deg) = 0
Zenith Ang (deg) = 0
Number of polns = 2 (summed)
Sample time (us) = 58.5937486903276
Central freq (MHz) = 5990
Low channel (MHz) = 5937.5968
High channel (MHz) = 6042.4032
Channel width (MHz) = 0.0512
Number of channels = 2048
Total Bandwidth (MHz) = 104.8576
Beam = 1 of 1
Beam FWHM (deg) = 1.000
Spectra per subint = 2400
Starting subint = 0
Subints per file = 0
Spectra per file = 10252288
Time per subint (sec) = 0.140624996857
Time per file (sec) = 600.719986573
bits per sample = 32
bytes per spectra = 8192
samples per spectra = 2048
bytes per subint = 19660800
samples per subint = 4915200
zero offset = 0
Invert the band? = False
bytes in file header = 389
rfifind -time 5.0 -o themask /data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil
(note: a value of -time > 5.0 produced a warning that the process would take too long, so I chose 5.0)
Pulsar Data RFI Finder
by Scott M. Ransom
Pulsar Data RFI Finder
by Scott M. Ransom
Assuming the data are SIGPROC filterbank format...
Reading SIGPROC filterbank data from 1 file:
'/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil'
Number of files = 1
Num of polns = 2 (summed)
Center freq (MHz) = 5990
Num of channels = 2048
Sample time (s) = 5.8593748690328e-05
Spectra/subint = 2400
Total points (N) = 10252288
Total time (s) = 600.71998657286
Clipping sigma = 6.000
Invert the band? = False
Byteswap? = False
Remove zeroDM? = False
File Start Spec Samples Padding Start MJD
---- ---------- ---------- ---------- --------------------
1 0 10252288 0 58243.71099537036935
Analyzing data sections of length 86400 points (5.0625 sec).
Prime factors are: 2 2 2 2 2 2 2 3 3 3 5 5
Writing mask data to 'themask_rfifind.mask'.
Writing RFI data to 'themask_rfifind.rfi'.
Writing statistics to 'themask_rfifind.stats'.
Massaging the data ...
WARNING: Found 0 bad powers in the datapow array. Zeroing them out.
There are 187 RFI instances.
Total number of intervals in the data: 243712
Number of padded intervals: 2048 ( 0.840%)
Number of good intervals: 240996 (98.886%)
Number of bad intervals: 668 ( 0.274%)
Ten most significant birdies:
# Sigma Period(ms) Freq(Hz) Number
----------------------------------------------------
1 32.86 306.818 3.25926 114
2 25.28 259.615 3.85185 125
3 21.68 0.1562515(70) 6399.94(29) 2195
4 20.71 273.649 3.65432 82
5 19.97 177.632 5.62963 88
6 19.42 165.984 6.02469 6
7 18.72 191.038 5.23457 18
8 18.58 266.447 3.75309 196
9 18.53 253.125 3.95062 205
10 17.65 0.312501(28) 3199.99(28) 1972
Ten most numerous birdies:
# Number Period(ms) Freq(Hz) Sigma
----------------------------------------------------
1 148015 1012.5 0.987654 7.91
2 131387 843.75 1.18519 8.32
3 122904 920.455 1.08642 8.32
4 91972 778.846 1.28395 7.81
5 28920 675 1.48148 7.50
6 24917 723.214 1.38272 7.64
7 21096 632.812 1.58025 7.40
8 20489 421.875 2.37037 6.20
9 19002 440.217 2.27161 6.21
10 16586 595.588 1.67901 7.16
Done.
According to This pulsar data query P=0.714519699726 and dm=26.7641
readline reports 10252288 Spectra per file. I chose the closest power of 2 as the -numout 8388608
prepdata -nobary -dm 26.7641 -o outfilename_DM -numout 8388608 -mask themask_rfifind.mask /data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil
NOTE! Had to edit ~/presto/tempo/obsys.dat and add the ATA, otherwise tempo does not work
Replaced:
382546.30 795056.36 893.7 GB 300FT 9 G3 with 40490264.0 1212818.48 1018.69 ATA 9 AT
NOTE: Not removing the G3 line first caused the following error:
Generating barycentric corrections... Error in chkfopen(): No such file or directory path = 'resid2.tmp'
Now it runs (removed the G3 line):
Pulsar Data Preparation Routine
Type conversion, de-dispersion, barycentering.
by Scott M. Ransom
Assuming the data are SIGPROC filterbank format...
Reading SIGPROC filterbank data from 1 file:
'/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil'
Number of files = 1
Num of polns = 2 (summed)
Center freq (MHz) = 5990
Num of channels = 2048
Sample time (s) = 5.8593748690328e-05
Spectra/subint = 2400
Total points (N) = 10252288
Total time (s) = 600.71998657286
Clipping sigma = 6.000
Invert the band? = False
Byteswap? = False
Remove zeroDM? = False
File Start Spec Samples Padding Start MJD
---- ---------- ---------- ---------- --------------------
1 0 10252288 0 58243.71099537036935
This is the ATA!
Read mask information from 'themask_rfifind.mask'
Attempting to read the data statistics from 'themask_rfifind.stats'...
...succeded. Set the padding values equal to the mid-80% channel averages.
Writing output data to 'outfilename_DM.dat'.
Writing information to 'outfilename_DM.inf'.
Generating barycentric corrections...
Average topocentric velocity (c) = 2.931167e-05
Maximum topocentric velocity (c) = 2.931716e-05
Minimum topocentric velocity (c) = 2.930619e-05
Collecting and barycentering /data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil...
The DM of 26.76 at the barycentric observing freq of 6042.580 MHz
causes a delay of 0.003042 seconds compared to infinite freq.
This delay is removed from the barycented times.
Topocentric epoch (at data start) is:
58243.71099537037
Barycentric epoch (infinite obs freq at data start) is:
58243.70731137398
Massaging the data...
Amount Complete = 100%
Done.
Simple statistics of the output data:
Data points written: 8388608
Bins removed for barycentering: 246
Maximum value of data: 1055630491648.00
Minimum value of data: 804496343040.00
Data average value: 930264209988.64
Data standard deviation: 39408852841.53
prepfold -dm 26.7641 -p 0.714519699726 /data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil -mask themask_rfifind.mask -nsub 2048
Pulsar Raw-Data Folding Search Routine
Used for DM, Period, and P-dot tweaking of PSR candidates.
by Scott M. Ransom
Assuming the data are SIGPROC filterbank format...
Reading SIGPROC filterbank data from 1 file:
'/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil'
Number of files = 1
Num of polns = 2 (summed)
Center freq (MHz) = 5990
Num of channels = 2048
Sample time (s) = 5.8593748690328e-05
Spectra/subint = 2400
Total points (N) = 10252288
Total time (s) = 600.71998657286
Clipping sigma = 6.000
Invert the band? = False
Byteswap? = False
Remove zeroDM? = False
File Start Spec Samples Padding Start MJD
---- ---------- ---------- ---------- --------------------
1 0 10252288 0 58243.71099537036935
Read mask information from 'themask_rfifind.mask'
Attempting to read the data statistics from 'themask_rfifind.stats'...
...succeded. Set the padding values equal to the mid-80% channel averages.
This is the ATA!
Folding a 714.52ms_Cand candidate.
Output data file is '/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018_714.52ms_Cand.pfd'.
Output plot file is '/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018_714.52ms_Cand.pfd.ps'.
Best profile is in '/data/psrB0329+54_5990mhz_58us_6ants_10min_may5_2018_714.52ms_Cand.pfd.bestprof'.
Folding (topo) epoch (MJD) = 58243.710995370369
Folding (bary) epoch (MJD) = 58243.707311373975
Data pt duration (dt) (s) = 5.85937486903e-05
Total number of data points = 10137600
Number of profile bins = 64
Folding period (s) = 0.714519699726
Folding frequency (hz) = 1.39954153872
True starting fraction = 0
Generating barycentric corrections...
The average topocentric velocity is 2.93118e-05 (units of c).
Barycentric folding frequency (hz) = 1.39954153872
Barycentric folding f-dot (hz/s) = 0
Barycentric folding f-dotdot (hz/s^2) = 0
Topocentric folding frequency (hz) = 1.39950050823
Topocentric folding f-dot (hz/s) = 2.374989e-11
Topocentric folding f-dotdot (hz/s^2) = -1.8167136e-14
Will search 385 DMs from 0.000 to 73046.868 (ddm = 189.7321)
Starting work on 'psrB0329+54_5990mhz_58us_6ants_10min_may5_2018.fil'...
Folded 158400 points of 10137600
pulsar_finding.1525641557.txt.gz · Last modified: 2023/10/28 18:36 (external edit)