How to adjust parameters to realistic pulse profile

[Hai0421]

Hi, I want to ask a question, I can't see the period when I fold down (J0030+00451） is a known pair of X-ray pulse sources), which parameter do I need to adjust? There is a detailed tutorial of this software, this software is very useful, thank you very much!

Below this is my par file and pulse chart

Created: 2024-10-20T19:10:47.654311

PINT_version: 1.0.1

User: hailei

Host: leihai.local

OS: macOS-15.0-arm64-arm-64bit

Python: 3.12.4 | packaged by Anaconda, Inc. | (main, Jun 18 2024, 10:07:17) [Clang 14.0.6 ]

Format: pint

PSRJ J0030+0451
EPHEM DE421
CLK TT(BIPM2011)
UNITS TDB
START 53331.8428259775636739 0 0.0
FINISH 57976.1329119150636760 0 0.0
TIMEEPH FB90
T2CMETHOD IAU2000B
DILATEFREQ N
DMDATA N
NTOA 2845
CHI2R 1.8068 0 2834.0
TRES 3.22
RAJ 0:30:27.42725720 1 0.00000001115045757510
DECJ 4:51:39.70757000 1 0.00000038809116409062
PMRA -6.288507497153388 1 0.20681023212444358
PMDEC 0.6155970864728986 1 0.48077763529257733
PX 2.6583873577563137 1 0.1475626504611243
POSEPOCH 55999.9998006651803735
F0 205.53069908812228 1 1.5014730632806368e-12
F1 -4.29804908390079e-16 1 3.2925379580757124e-21
PEPOCH 55999.9998006651803735
TZRMJD 55655.4797077947792824
TZRSITE f
TZRFRQ 1438.234009
JUMP TEL nancay 8.036571461288969e-06 1 0.0
PLANET_SHAPIRO Y
NE_SW 4.000000124041585
SWM 0
DM 4.33397101341168 1 0.000338569307285196
DM1 0.0001505929231760213 1 0.00010677755921359501
DMEPOCH 55999.9998006651803735

[Hai0421]

psrpipe.py --par J0030+0451_tdb.par --ephem DE405 1060020361

[Hai0421]

Is there a tutorial for this software? Hope to share

[paulray]

There is a lot of info at this workshop, including a timing tutorial by Megan DeCesar: https://heasarc.gsfc.nasa.gov/docs/ixpe/analysis/workshop/joint2024.html

[paulray]

I tried your specific command and I get the same result. There isn't any problem, just that there is quite a bit of background in this observation and you are allowing all energies from 0.25-15.0 keV, so the signal is swamped out. If you restrict your energy cuts to 0.25-1.5 keV you will see the pulsar with an H-test of 96. You can do this with --emin 0.25 --emax 1.5 or by using ftselect on the output cleanfilt.evt file. The way to determine the optimal cuts is to use nioptcuts.py. Hope that helps.

[Hai0421]

Thank you very much for your response. Additionally, the generated plot shows significant fluctuations in counts (Figure 1). Is it possible to adjust the bin size or download multiple files from the same source to increase exposure, making the profile smoother (like Figure 2)? Such a plot is not suitable for scientific analysis. Thank you for your help

[paulray]

Certainly, you are just looking at 1 ObsID. There are several megaseconds of data on this pulsar in the NICER archive. What are you trying to do? If you just want a high S/N profile from NICER, you could just use the dataset published here: https://zenodo.org/records/3524457

[Hai0421]

OK, I seem to understand. Thanks for your patient help

[Hai0421]

Can this software directly read the J0030+0451_merged_phase_0.25-3keV.fits file provided in the web page to generate the graph? Or do you need to write python code to read it?

[paulray]

That is just a FITS event list that many codes can read, including various FTOOLS. The scripts in NICERsoft like niphaseogram.py and plotphist.py can read it. It is also very easy to read in python and plot in whatever way you need.

[Hai0421]

thank you1