今日记录

Extract GPS Image Cutouts

https://third.ucllnl.org/cgi-bin/gpscutout

 

python的各种项目https://python3statement.org/

时长8个半小时的python视频，需梯子https://www.youtube.com/watch?v=pJ3IPRqiD2M

https://irsa.ipac.caltech.edu/applications/Herschel/

https://www.cosmos.esa.int/web/herschel   

https://irsa.ipac.caltech.edu/data/SPITZER/GLIMPSE/gator_docs/GLIMPSE_colDescriptions.html

https://www.bu.edu/galacticring/     Galactic  Ring  Survey  ( GRS ) 13 CO  data

hco+ and 12CO是双极外向流的很好的示踪分子

12CO常用来说明红外尘泡周围存在外向流

氢电离区可以触发恒星形成，主要有两个机制，collect -and- collapse  adiation-driven implosion   

下面是今日看的论文MOLECULAR LINES OF 13 GALACTIC INFRARED BUBBLE REGIONS 的数据来源：   

 GLIMPSE     the Multiband Imaging Photometer for Spitzer ( MIPS ) Galactic Plane Survey ( MIPSGAL;）

 the APEX Telescope Large Area Survey of the Galaxy ( ATLASGAL）

 the Bolocam Galactic Plane Survey ( BGPS）

 the Very Large Array ( VLA ) Galactic Plane Survey ( VGPS）

 the Multi-Array Galactic Plane Imaging Survey ( MAGPIS）

 the NRAO VLA Sky Survey ( NVSS）

N75 38.928 − 0.386 1.2 1.3 2.0 25 42.1 6.2 2.8 / 10.4

http://www.radioast.nsdc.cn/publication.php  用德令哈13.7m做的论文

 

Position-independent actions:
   Press E key: EXIT loop
   Press H key: HELP display
   Press M key: MOVIE
   Press P key: PRINT plot in "ha" subdirectory
   Press Q key: QUIT loop
   Press X key: EXTRACT on disk current zoomed region
Position-dependent actions:
   Cursor on images:
      Left  clic: Display spectrum at pointed position
      Right clic: Define a polygon
      Press C key: COORDINATES toggled from absolute to relative and back
      Press S key: SLICE definition (velocity-position)
      Press K key: KILL   pointed pixel
      Press U key: UNKILL pointed pixel
      Press Z key: ZOOM defined spatial region
      Press B key: BACK to full field of view
      Press V key: Display map coordinates at current position (the associated brightne
ss value is wrong)                                                                                        
      Press W key: WRITE Integrated Area image
   Cursor on spectra:
      Left clic in Selected   Spectrum: Display selected velocity channel
      Left clic in Integrated Spectrum: Define velocity range
      Press C key: COORDINATES toggled from freq/velo to channels and back
      Press Z key: ZOOM defined velocity region
      Press B key: BACK to full velocity range
      Press W key: WRITE Integrated (and current) Spectrum
   Cursor outside plots:
      Press B key: BACK to full velocity range AND full field of view
Known problems:
   1. Velocity range may be wrong when successively using go view on 2
      different cubes

　　上面是在class中显示lmv文件后出现的快捷键信息。

 

以下内容来自：http://loke.as.arizona.edu/~ckulesa/smt/pmap.html

动态地图通常以固定的时间间隔生成光谱仪的读数，而不是在天空中的固定位置。天线的轻微加速或减速会导致不规则采样的地图，尽管通常只是轻微的。在对地图进行适当的分析之前，必须对其进行网格化和卷积。

让我们看一张rho-Oph暗云的HCO+J=4-3（356ghz）图，在rho-Oph核心附近。当望远镜每分钟移动80弧秒时，数据每3秒采样一次。只经过地图一次。这导致1/6波束采样，消除了扫描方向上的模糊。快速扫描，每个样品最多1/4束，也通常在HHT进行。

首先，我们像处理常规采样数据一样执行基本处理（去除基线的低阶拟合）。打开新处理的文件，我们现在在class中使用grid命令对数据进行重网格化并将其卷积到波束大小（356 GHz时为22”），将-20到30 km/s Vlsr之间的channel存储到数据立方体：

file in hcop43.smt
find
grid hcop43.gtf new /channel v -20 30 /image beam 22　　




help grid
        [GREG2\]GRID [Astep [Dstep]] [/ALTERNATE] [/LABEL]
 
    Plots  a grid of meridian and parallels according to the current projec-
    tion and system. Astep is the grid step for meridian in degrees (Default
    15), Dstep for Parallels (Default Astep). If one step is 0, this part of
    the grid is not plotted. If the /ALTERNATE option is present,  the  grid
    will  be a grid in the alternate coordinate system (Equatorial or Galac-
    tic). This does not currently work for projection type AITOFF and RADIO.
 
    If /LABEL is present, the meridians and parallels will be  labeled  with
    their absolute coordinates.






 根据当前投影和系统绘制子午线和平行线网格


上面实在class中进行的，下面开始转换到greg。




 GRAPHIC> run moments
Input file name
FILE        IN$                              = hcop43.lmv
Output files name (no extension)
FILE        OUT$                             = hcop43
Velocity range
REAL        VELOCITY$[2]                     = 0 6
Detection threshold
REAL        THRESHOLD$                       = 0
Smooth before detetction ?
LOGICAL     SMOOTH$                          = no
I-RUN,  Task moments running, logfile is
        /home/ckulesa/moments.gildas




moments会产生三个文件，hcop43.mean,包含积分强度的图，hcop43.vel,包含中心速度的图；hcop43.width,包含线宽的图。


首先让我们绘制积分强度图。


从实际数据中获取X-Y强度plotting limits，绘制颜色wedge，重新采样到100x100像素的图像，并设置类似AIPS的颜色方案，将等高线间距设置为4 K km/s（从4 K km/s开始），绘制等高线，并生成用于打印的彩色Postscript文件：




GRAPHIC> image hcop43.mean
W-GDF_RHSEC,  Absent section EXTREMA
W-GDF_RHSEC,  Absent section RESOLUTION
W-GDF_RHSEC,  Absent section NOISE
    GRAPHIC> limits /rgd
    GRAPHIC> set box square
    GRAPHIC> plot
    GRAPHIC> wedge
    GRAPHIC> resample 100 100 /bl 0
I-RESAMPLE,  Got    79 pages of virtual memory
    GRAPHIC> box /u s
S-CHAR,  Fonts loaded
    GRAPHIC> let hue[i] = 256-2*i
    GRAPHIC> lut
    GRAPHIC> plot
    GRAPHIC> wed
    GRAPHIC> levels 4 to 30 by 4
I-LEVELS,  Contour levels are :
     4.000         8.000         12.00         16.00         20.00
     24.00         28.00
    GRAPHIC> rgmap
I-RGMAP,  Contouring checks the blanking value   0.00000
I-RGMAP,  Pens  0 & 15 used for positive & negative levels
I-RGMAP,  Contour   1   4.00000
I-RGMAP,  Contour   2   8.00000
I-RGMAP,  Contour   3   12.0000
I-RGMAP,  Contour   4   16.0000
I-RGMAP,  Contour   5   20.0000
I-RGMAP,  Contour   6   24.0000
I-RGMAP,  Contour   7   28.0000
    GRAPHIC> hardcopy hcop43.ps /dev ps color




 制作符合发表要求的图片


image aspect ration


set box square


set box match


pencil /weight 2


label "offset RA('')" /x


label "offset Dec('')" /y


draw text


draw line


draw arrow


draw marker


draw relocate


 


ellipse 0.000052 /user -75 330 seconds /fill 0     


 下面的网址是和fits cube文件提取moments 0 1 2 有关的


Spectral Line Processing   https://www.icrar.org/wp-content/uploads/2018/11/Lee-Waddell_Spectral_Line_Processing.pdf


Moment maps and statistics   https://spectral-cube.readthedocs.io/en/latest/moments.html


https://learn.astropy.org/rst-tutorials/FITS-cubes.html


Computing the Moments of an Image Cube (immoments)


https://spectral-cube.readthedocs.io/en/latest/examples.html




>>> import astropy.units as u
>>> from astropy.utils import data
>>> from spectral_cube import SpectralCube
>>> fn = data.get_pkg_data_filename('tests/data/example_cube.fits', 'spectral_cube')
>>> cube = SpectralCube.read(fn)
>>> print(cube)
SpectralCube with shape=(7, 4, 3) and unit=Jy / beam:
 n_x:      3  type_x: RA---ARC  unit_x: deg    range:    52.231466 deg:   52.231544 deg
 n_y:      4  type_y: DEC--ARC  unit_y: deg    range:    31.243639 deg:   31.243739 deg
 n_s:      7  type_s: VRAD      unit_s: m / s  range:    14322.821 m / s:   14944.909 m / s

# extract the subcube between 98 and 100 GHz
>>> slab = cube.spectral_slab(98 * u.GHz, 100 * u.GHz)  

# Ignore elements fainter than 1 Jy/beam
>>> masked_slab = slab.with_mask(slab > 1 Jy/beam)  

# Compute the first moment and write to file
>>> m1 = masked_slab.moment(order=1)  
>>> m1.write('moment_1.fits')  





　　






		

		
posted @ 
2021-04-06 09:20 
cql_astro 
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