又开始Arecibo观测了，这次还是远程观测，用L band wide接收机，比ALFA简单一些。基本操作和上次一样（http://blog.sciencenet.cn/blog-117333-633170.html），    不过登录验证比上次复杂了些。首先，找管理员要一个账户名（就是项目号）和密码（24小时内有效）。然后尽快登录Arecibo的服务器

ssh -l <username> -p 2222 remoter.naic.edu

登上以后就运行

2f-setup

然后，按照手册的说法

“there will be a text menu called Ssh authentication key          setup: with different options, select ssh          authentication: key generation and private-key export          (openssh+putty): you will be asked to enter a      passphrase which will be used to encrypt the key, enter the      passphrase (and don't forget it). On screen will appear the      content of the openssh private key, something like:

-----BEGIN DSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,22BCB93B49F2FCD3D9EAB023C328229E
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-----END DSA PRIVATE KEY-----
       ”

然后在自己本地的机器上开一个文本文件id_dsa，把上面那段天书（不含第一行和最后一行）放到这个文件里。这段天书就是此后登录Arecibo服务器的密码。然后

chmod go-rw id_dsa
       然后按照手册的说法

“

You will need the file id_dsa in order to login to the Arecibo      

Observatory from a Linux or MacOS PC. Now go back to the first      

terminal and press Return, on screen will appear the content of      

the putty private key, something like:

PuTTY-User-Key-File-2: ssh-dss
Encryption: aes256-cbc
Comment: Arecibo-Observatory-Key
Public-Lines: 10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Private-Lines: 1
kaK52/a9HtZyQFmUlb6XJzseHIW+ozur4+vF8tRRzxo=
Private-MAC: 1881513f7aff443be94f9bb31616b59909c96971
”

然后在本地机器上开一个文本文件id_dsa.ppk，然后把上面这段天书填进去（不过这玩意儿好像是苹果和Windows用的）。Linux不需要。然后

chmod go-rw id_dsa.ppk

然后按照手册

“Now go back to the first      

terminal and press Return, on screen there will be a text menu    

called Google authenticator setup: with different options, select create google authenticator TOTP secret      

key.

You will be asked three questions, you can    

safely answer yes to all of them.

On screen will appear the      

content of the google authenticator TOTP secret key, a 16      

characters text string like:        

O3KD63KZDDCHMIUF”

最后这一段密码是通过网页获得验证码（https://www.naic.edu/2f/ ）要用到的密码。至此，验证的准备工作就完成了。然后，开始准备登录Arecibo服务器。

ssh-add id_dsa

然后

ssh -X -A username@remoter.naic.edu

登上以后就可以无需密码登录dataview了

ssh -X dataview

然后可以开一个vnc窗口

vncserver -geometry 1280x1024

记住窗口号NN就可以像上一次那样登录vnc远程桌面了。

vncviewer -via username@remote.naic.edu dataview:NN

如果要下载数据，需要用scp，也要像vnc那样通过ssh转接。

ssh -N -A -L 2222:hostname:22 username@remote.naic.edu    

然后在另一个shell窗口

   scp -P 2222 username@localhost:pathname-on-hostname local-file-name
   观测过程和上次类似。不过这次写了几个脚本，可以随时查看数据了（注意，在dataview上运行IDL时，先要
   IDL> @phil
   IDL> @wasinit2
   然后再运行程序。）。

   列出某个项目的所有数据（shell）
   ====================================
   #!/bin/sh
   ls /share/obs4/wappdata/wapp.*.projectname.*.fits
   ====================================

   列出某个数据文件中的内容（IDL）
   ====================================
   PRO a_list,filename
   is=wasopen(filename,desc)
   waslist,desc
   END
   ====================================

   画出一条频谱（IDL）
   ====================================
   PRO a_plot,filename,scannum
   is=wasopen(filename,desc)
   waslist,desc
   is=corposonoff(desc,b,scan=scannum,/han,/sclcal)
   corplot,b,/vel
   END
   ====================================

   叠加谱线（IDL）
   ====================================
   PRO a_add,filename,scannum,badd,new,x1,x2,y1,y2
   is=wasopen(filename,desc)
   waslist,desc
   is=corposonoff(desc,b,scan=scannum,/han,/sclcal)
   coraccum,b,badd,new=(new eq 1)

   corplot,badd,/vel

   hor,x1,x2

   ver,y1,y2

   END
   ====================================