X-ray数据处理笔记：Chandra Timing Analysis

1.0 Download the data

观测号为953和461

1. 官网下载

下载数据的网址：https://cda.harvard.edu/chaser/

在Observation ID输入观测ID953,461
点击Search
Select all
Add Products to Retrieval List
Retrieve Products

点击网址

下载压缩包
解压

2. ciao下载

~/chandra/test5 » ciao  #初始化ciao
(ciao-4.12) --------------------------------------------------------------------
~/chandra/test5 » download_chandra_obsid 953,461 #下载数据
Downloading files for ObsId 11823, total size is 366 Mb.

  Type     Format      Size  0........H.........1  Download Time Average Rate
  .
  .
  .
Total download size for ObsId 11823 = 366 Mb
Total download time for ObsId 11823 = 7 m 19 s

1.1 数据预处理

~/chandra » chandra_repro 953，461 outdir="" verbose=5   

Running chandra_repro
version: 03 April 2020

进入预处理后的repro目录

1.2 质心修正

别忘了初始化ciao

ciao
punlearn axbary
pset axbary infile=acisf00953_repro_evt2.fits
pset axbary orbitfile=../primary/orbitf069509100N001_eph1.fits
pset axbary outfile=acis_953_bary_evt2.fits
pset axbary ra=6.02430 dec=-72.08090
axbary

dmhedit acisf00953_repro_evt2.fits file= op=add key=ASOLFILE value="pcad_133_bary_asol1.fits"
dmhedit acisf00953_repro_evt2.fits"[cols time]" data rows=1:6

用ds9打开acis_953_bary_evt2.fits文件

ds9 acis_953_bary_evt2.fits -cmap b -scale log &

1.3 Edit -> Region

分别做出如下三个区域，并用ds9打开

ds9 acis_953_bary_evt2.fits -cmap b -scale log -region src1.reg -region src2.reg -region bkg.reg

a: For src1

punlearn dmextract
dmextract infile="acis_953_bary_evt2.fits [ccd_id=3,sky=region(src1.reg)][bin time=::2000]" outfile="src1_sub_lc.fits" bkg="acis_953_bary_evt2.fits[ccd_id=3,sky=region(bg.reg)]" opt="ltc1" clobber=yes verbose=2

b: For src2

punlearn dmextract
dmextract infile="acis_953_bary_evt2.fits[ccd_id=3,sky=region(src2.reg)][bin time=::2000]" outfile="src2_sub_lc.fits" bkg="acis_953_bary_evt2.fits[ccd_id=3,sky=region(bg.reg)]" opt="ltc1" clobber=yes verbose=0

1.4 Plot the light curves

a: For src1 by fv in Heasoft

初始化heasoft,用fv打开fv src2_sub_lc.fits

h
fv src2_sub_lc.fits &

LIGHTCURVE>>Plot
设置坐标

然后Print,保存

b: For src1 by python

写python脚本

vi pl.py

脚本内容如下

```python
from pycrates import read_file
import matplotlib.pylab as plt

tab = read_file("src2_sub_lc_400.fits")
dt = tab.get_column("dt").values
rate = tab.get_column("net_rate").values
erate = tab.get_column("err_rate").values

plt.errorbar(dt, rate, yerr=erate,marker="o",color="red", mfc="black", mec="black", ecolor="grey")
plt.xlabel("$\Delta$ T (sec)")
plt.ylabel("Net Count Rate (counts/sec)")
plt.title("src2_sub_lc_400.fits")
plt.show()

用python运行pl.py

python pl.py

如图

2.0 Surce2 lightcurve with 200s time-bin(分为200bins,上面操作为2000bins)

改为200bins

punlearn dmextract
dmextract infile="acis_953_bary_evt2.fits[ccd_id=3,sky=region(src2.reg)][bin time=::200]" outfile="src2_sub_lc_200.fits" bkg="acis_953_bary_evt2.fits[ccd_id=3,sky=region(bg.reg)]" opt="ltc1" clobber=yes verbose=0

画图

3.0 Light curve for HRC(高分辨率CDD461)

Update two files

punlearn axbary
pset axbary infile=pcadf064938693N003_asol1.fits
pset axbary orbitfile=../primary/orbitf064886464N002_eph1.fits
pset axbary outfile=pcad_461_bary_asol1.fits
pset axbary ra=187.2779170 dec=2.0523890
pset axbary clobber=yes
axbary mode=h