Nobeyama Radioheliograph (NoRH)
Analysis Manualver. 3.3
International Consortium for the Continued Operation of Nobeyama Radioheliograph
April 1, 2015

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Contents
1 Change Log

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2 Introduction

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3 How to set up the Analysis Softwares
3.1 For analysis with IDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 For analysis without IDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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4 Analysis with IDL
4.1 Start up SSW/IDL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Data Base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.1 Observation Time and Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.2 Event List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Time-series data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.1 Correlation tcx data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3.2 Correlation tsx data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 Image Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.1 Image Files at NoRH Data Archive . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4.2 Pre-Processing for Image Synthesis — Transfer of Raw Data . . . . . . . . . . . .
4.4.3 Image Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.1 Read and display images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.2 Beam Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.3 Coordinate grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.4 Getting Information about Images . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.5 Using map procedure of the SolarSoftware . . . . . . . . . . . . . . . . . . . . . . .
4.5.6 Derivation of Flux Density (Fν ) from Brightness Temperature (Tb ) . . . . . . . . .
4.5.7 Circular Polarization Degree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.8 Make the Size of Beams Same between Two Images . . . . . . . . . . . . . . . . .
4.5.9 Spectrum Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5.10 Curves of Flux, Circular Polarization, and Spectrum Index from a Partial Area . .
4.5.11 Optically-Thin Non-Thermal Gyrosynchrotron Emission . . . . . . . . . . . . . . .
4.5.12 Optically-Thin Thermal Free-Free Emission . . . . . . . . . . . . . . . . . . . . . .
4.6 Example of Analysis Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.1 Choose an Event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.2 Light Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.3 Image Synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.4 Image Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.5 Polarization Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.6 Spectrum Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6.7 Interpretation of Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7 Others . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.1 Read Raw Data Directly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.2 Antenna/Antenna-Pair ID and Name . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.3 Sun Position at Nobeyama . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7.4 Make original SZ ﬁle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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5 Analysis without IDL
5.1 Data Base . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 Time-series data and Images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Image data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.1 Image Files at NoRH Data Archive . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.2 Transfer of raw data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3.3 Image synthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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6 Detailed Description of Synthesis Programs
6.1 Hanaoka . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2 Koshix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3 Fujiki . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.4 Compilation of synthesis programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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A NoRH data
A.1 Observation mode of NoRH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.2 What is Schedule for NoRH ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.3 Raw data (ss17,ss34,se17,se34) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.4 ’SZ’ data (sz00) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.5 Images (ifa,ifs,ifz,ipa,ips,ipz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.6 Observation Time (info) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.7 R/L phase diﬀerence (rlphdif) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.8 Averaged correlation (tsa,tsz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.9 Averaged correlation Digest (tca,tcz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.10 Event list (eva,evz) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.11 Observation log (lob) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.12 Tohban report (rep) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A.13 Sun tracking table (track table) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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B NoRH FITS header
B.1 Header Regulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B.2 Example of Header . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B.3 Implimentation to subroutines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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C NoRH data archive: anonymous FTP

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D Acknowledgement

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Change Log• Version 2.3e: 25 October 2001, written by Yokoyama, T.
• Version 3.0e: 7 September 2007, modiﬁed by Meshalkina, N.
• Version 3.3e: 1 April 2015, modiﬁed by Shimojo, M.

2Introduction

This is a manual for analyzing the data of Nobeyama Radioheliograph [NoRH] that is an imaging solar
radio telescope (17/34GHz) operated by the International Consortium for the Continued Operation of
Nobeyama Radioheliograph (ICCON) leaded by the Solar-Terrestrial Environment Laboratory, Nagoya
University (Nakajima et al. 1994; Nishio et al. 1994; Hanaoka et al. 1994). The contents are as follows:
Section 3 describes how to install this package, Section 4 describes how to analyze the data using IDL.
Section 5 describes how to analyze without IDL. The detailed description of synthesis programs are given
in Section 6. Appendix A and B give the detailed information on NoRH data and on the FITS header
used, respectively. A brief introduction of the NoRH data archive is given in the last section Appendix
C.
For any questions and requests, please send an e-mail tonorh-help[|-at-|]st4a.stelab.nagoya-u.ac.jp[|-at-|] = @3

How to set up the Analysis Softwares

To use the softwares that are introduced in this manual, the following set-up is necessary.

3.1

For analysis with IDL(1) Installation of the SolarSoftware.
Install the SolarSoftware (SSW) with the subpackage ’Radio/NoRH’. We strongly recommend to install the SolarSoftware with the sub-package for Yohkoh/SXT. If these softwares were not installed, pleasecontact your system manager. The primary distribution site for SolarSoftware is: http://www.lmsal.com/solarsoft/
We deﬁne the top directory of SSW as ${SSW} and that of NoRH subpackage as ${NORH} (usually${SSW}/radio/norh) in this manual.
(2) Installation of NoRH data base
Copy the NoRH data base after getting them from the NoRH distribution from the NoRH data archiveat ftp://solar-pub.nao.ac.jp/pub/nsro/norh/data. The recommended destination is ${NORH}/data.
(3) Setup of your personal environment
Include the followings in your environment setup ﬁle (~/.cshrc).
setenv SSW SSW-directory1
setenv SSW INSTR ‘‘norh’’setenv NORH ${SSW}/radio/norhsource ${SSW}/gen/setup/setup.ssw
source ${NORH}/setup/setup.norh
Note that the enviroment variable ${SSW} can be diﬀerent (Ask your system manager)2 . In case you
analyze many kinds of data at the same time, deﬁne SSW INSTR as follows, e.g.
setenv SSW INSTR ‘‘sxt hxt norh’’In some sites, to save the disk space, the NoRH data base could be installed somewhere that is not thedefault place (${NORH}/data) 3 . In this case, include following
setenv NORHDB data-base-directory
1 /ssw in SDAS
2 In SDAS, it is /ssw
3 In SDAS, it’s in default place.

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3.2

For analysis without IDL(1) Installation of NoRH software package
Install the NoRH software package. The destination directory is basically arbitrary. We deﬁne thistop directory as ${NORH} in this manual.
(2) Installation of NoRH data base
Copy the NoRH data base after getting them from the NoRH distribution from the NoRH data archiveat ftp://solar-pub.nao.ac.jp/pub/nsro/norh/data. The recommended destination is ${NORH}/data.
(3) Setup of your personal environment
Include the followings in your environment setup ﬁle (~/.cshrc).
setenv NORH NoRH-directorysource ${NORH}/setup/setup.norh
Note that the enviroment variable ${NORH} can be diﬀerent (Ask your system manager)4 . In some sites,
to save the disk space, the NoRH data base could be installed somewhere that is not the default place(${NORH}/data) 5 . In this case, include following
setenv NORHDB NoRH-data-base-directory

4 In SDAS, it is /nfs/nobeyama solar/pub/norh
5 In SDAS, it’s in default place.

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Analysis with IDL

4.1

Start up SSW/IDL

The NoRH IDL procedures described in this section all depend on the SolarSoftware (SSW). When you
start the analysis, start up the SSW/IDL as follows:
unix% sswidl <CR>
If you start up the SSW/IDL on SDAS, the start-up command is as follows:
unix% SSWidl <CR>

4.2

Data Base

4.2.1

Observation Time and Logs

There is a data base for the observation time (’info’ data: Appendix A.6). For example, to see theobservation time of the schedules on 1998-7-25 UT of 17GHz steady-mode (1sec integration) data,
IDL> norh pr info,’1998-07-25’ <CR>or for data from 1998-7-25 to 1998-7-28,
IDL> st time=’1998-07-25’ <CR>
IDL> ed time=’1998-07-28’ <CR>
IDL> norh pr info,st time,ed time <CR>
For 17GHz event-mode (50/100 msec integration) data,
IDL> norh pr info,st time,ed time,/event <CR>
For 34GHz event-mode data,
IDL> norh pr info,st time,ed time,/event,freq=34 <CR>
Then you will get
Start
(UT)
1998-06-30 22:45:22
1998-07-01 22:45:24

End
(UT)
06:44:56
06:44:57

Schedule

StFr

EdFr

980701980702

1
1

28775
28774

One line is for one NoRH schedule (Appendix A.2). From left, start time,end time, schedule ID, startframe number, end frame number. If you see the observation logs (’lob’ data: Appendix A.11),
IDL> norh pr info,st time,ed time,/log <CR>
You will get### 92/07/24
Data between 08:03 and 08:35 were lost.
### 92/07/31*Phase tracking software bug was fixed. Phase jumps which were found every
250 sec. will disappear.

4.2.2

Event List

There is a data base for the events (’evx’ data: Appendix A.10). In order to list them, e.g. on 1998-4-23
UT,
IDL> norh pr evx,’1998-04-23’ <CR>or for data from 1998-4-23 UT to 4-27 UT,
IDL> st time=’1998-04-23’ <CR>
IDL> ed time=’1998-04-27’ <CR>
IDL> norh pr evx,st time,ed time <CR>
For 34 GHz event list,
IDL> norh pr evx,st time,ed time,freq=34 <CR>
For the events that are beyond some averaged correlation value (say, 1.5 %),IDL> norh pr evx,st time,ed time,criterion=0.015 <CR>
To see GOES class and NOAA ID of the active regions of the events6 ,IDL> norh pr evx,st time,ed time,/goes <CR>
6 It is necessary to have the Yohkoh software and data base installed.

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Moreover you can display even with Yohkoh/HXT counts7 ,IDL> norh pr evx,st time,ed time,/goes,/hxt <CR>
Then
Start
(UT)
1992-11-02 02:40:31
1992-11-05 06:06:44
1992-11-23 03:33:42

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Peak
(UT)
02:49:18
06:20:41
04:31:07

End(UT)
03:40:30
06:39:59
06:37:18

Dur
(sec)
3599
1995
11016

Max Cor. / GOES NOAA Loca- /(x 10^-4) /tion /
1769 / X9.0/
171 / M2.0/
555 / C9.1 7347 S09W13 /

HXT
Low
5278
68
12

Med1
1500
36
7

Med2
210
22
5

High
30
15
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Time-series data

After the daily observation, ﬁles that contain the averaged correlation value are automatically createdfrom the raw data. This data is convenient for quick-look of the data. Deﬁnition of ’correlation’ is ”averaged values of correlation of antenna pairs (after removing short base-line pairs) of NoRH”. Correlation
increases as a strong microwave signal comes due to e.g. a ﬂare. So it is used instead of the real light
curve (plot of ﬂux density). For 17 GHz plot, 1 % of correlation corresponds to 30 SFU ﬂux density. It
is used because much computation resource is necessary for image synthesis that is the only method to
obtain ﬂux density at each time (see section 4.5.6). And correlation has an advantage that it is almost
not aﬀected by the weather condition. However, it does not increase when the ﬂux is so strong because
it has an upper limit of unity.
4.3.1

Correlation tcx data

The ’tcx’ data is relatively small that uses less memory space (Appendix A.9). But it has no information
on circular polarization, and time accuracy is about 1 sec. To read this data, e.g. 1998-4-20 JST 17GHz,
IDL> norh rd tcx,’1998-4-20’,index,data <CR>
e.g., from 1998-4-23 JST to 4-27
IDL> norh rd tcx,’1998-4-23’,’1998-04-27’,index,data <CR>
for 34GHz,
IDL> norh rd tcx,’1998-4-20’,index,data,freq=34 <CR>
You can directly give the ﬁle name as an argument
IDL> norh rd tcx,ﬁle,index,data <CR>
To plot the data use the Solar Software standard routine utplot
IDL> utplot,index,data <CR>

4.3.2

Correlation tsx data

The ’tsx’ data is relatively huge but including the circular polarization information (for 17GHz only),
and the time accuracy is 1 msec (Appendix A.8). To read this data, e.g. 1998-4-20 JST 17GHz,
IDL> norh rd tsx,’1998-4-20’,index,data <CR>
e.g., from 1998-4-23 JST to 4-27
IDL> norh rd tsx,’1998-4-23’,’1998-4-27’,index,data <CR>
for 34GHz,
IDL> norh rd tsx,’1998-4-20’,index,data,freq=34 <CR>
You can directly give the ﬁle name as an argument
IDL> norh rd tsx,ﬁle,index,data <CR>
to plot the data use the Solar Software standard routine
IDL> utplot,index,data(0,*) <CR> ; 17GHz RCP component
IDL> utplot,index,data(1,*) <CR> ; 17GHz LCP component
IDL> utplot,index,data <CR> ; 34GHz

7 It is necessary to have the Yohkoh software and data base installed.

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4.4

Image Synthesis

4.4.1

Image Files at NoRH Data Archive

Some synthesized images (Table 1) are put in the NoRH data archive (Table C). You can obtain themby anonymous FTP. Before synthesizing by yourself, try them ﬁrst.
Table 1: Image Files at NoRH Data ArchiveData
10 min. interval@3:00 UT (noon in Japan)
Event∗
Weak Event∗Frequency
17GHz
17/34GHz
17/34GHz
17/34GHz

Synth. Prog.
koshixkoshix/hanaoka
hanaoka/fujiki
hanaoka

Covered duration
since 1999
since Jul 1992
since Jun 1992
since Jun 1992

Directory
images/10minimages/daily
images/event
images/eventw*: The ’Event’s here have peak correlation more than 1.5 %, the ’Weak Event’s have more than 0.5 %and less than 1.5 %.

4.4.2

Pre-Processing for Image Synthesis — Transfer of Raw Data

You have to transfer the raw-data and ’SZ’ ﬁles (Appendix A.3 and A.4) from NoRH data archive(Appendix C) to your computer through the network before synthesis of the NoRH images.
(1) Basics
For example, to transfer the raw data that is necessary to synthesize one frame (image) every 600
seconds between 1997-4-20 1:30 UT and 3:30 UT,
IDL> st time=’1997-04-20 1:30:00’ <CR>
IDL> ed time=’1997-04-20 3:30:00’ <CR>
IDL> interval=600 <CR>
IDL> norh trans,st time,ed time,interval <CR>
(2) Images at speciﬁc times
To transfer the raw data that is necessary for synthesis of images at speciﬁc times,
IDL> time=[’1997-04-20 1:30:00’,’1997-04-20 1:40:00’ ,’ 1997-4-21 2:00:00’] <CR>
IDL> norh trans,time <CR>
(3) 34GHz
To transfer 34GHz data,
IDL> norh trans,time,freq=34 <CR>
(4) Event-mode
To transfer event-mode data,
IDL> norh trans,time,/event <CR>
4.4.3

Image Synthesis

This package has three programs for synthesis, See table 2 for supporting data. Detailed description foreach program is given in Section 6.
Note ! All the synthesis programs are written in Fortran 77 (partially 90). The IDL procedures describedin this section call externally the executive binaries of these programs. We prepared the binaries for Intelx86 with Linux OS architectures in this package. So it is possible to synthesize the NoRH package on
machines with these architecture. To run on others, it is necessary to compile them by yourself (Youhave to purchase commercial numerical library in this case. See Section 5 for detail.).
(1) Basics
For example, to synthesize one frame (image) every 600 seconds between 1997-4-20 1:30 UT and 3:30
UT,
IDL> st time=’1997-04-20 1:30:00’ <CR>

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IDL> ed time=’1997-04-20 3:30:00’ <CR>
IDL> interval=600 <CR>
IDL> norh synth,st time,ed time,interval <CR>
Note that in this case, the synthesis program runs on the local workstation (Linux with Intel x86 architecture) that you are working on.
(2) Non-uniformly spaced
You may synthesize the images non-uniformly in time. For example, for images at 1997-4-20 1:30,
1:40 and 1997-4-21 2:00 UT,
IDL> time=[’1997-04-20 1:30:00’,’1997-04-20 1:40:00’ ,’1997-4-21 2:00:00’] <CR>
IDL> norh synth,time <CR>
(3) 34GHz
For synthesis of 34GHz images8 ,IDL> norh synth,time,freq=34 <CR>
(4) Event mode
To synthesize the data of the event mode:
IDL> norh synth,time,/event <CR>
(5) Koshix, Fujiki
The default synthesis program is Hanaoka. To use Koshix or Fujiki, 9 :IDL> norh synth,time,prog=’koshix’ <CR>
(6) Partial Sun image
For partial Sun images, the spatial shift from the Sun center to the image center and the size of theﬁeld of view have to be given. The spatial shift could be given by unit of [1] arc-seconds or [2] pixel.
See table 2 for size of pixel in unit of arcsec. The size of FOV is given as number of pixels. See table 2
for size of ﬁeld of view in unit of pixels for each synthesis program. For example, for an image that has(-431,54) arc-seconds shift from the Sun center to the image center and with FOV (256× 256) pixels,
IDL> norh synth,time,cenunit=1,cenfnl=[-431,54],size=256 <CR>
For (100,-20) pixel shifted image with FOV (128× 128) pixels,
IDL> norh synth,time,cenunit=2,cenfnl=[100,-20],size=128 <CR>
(7) Syntesize an image at the designated time
In default, the frame to be synthesized is chosen by using ’info’ data (Appendix A.6). But in thiscase it sometimes chooses the frame a little bit (1-sec at maximum) away from the designated time. If
you need to synthesize image with more accurate timing, use ’tsx’ data (Appendix A.8) as follows10
IDL> norh synth,st time,ed time,interval,/usetsx <CR>

4.5

Data Analysis

4.5.1

Read and display images

You can directly give the ﬁle names as an argument.
IDL> norh rd img, ﬁle, index, data <CR>
Then, the images of brightness temperature (unit K) is stored in array ’data’ and structure ’index’. To
display
IDL> stepper, data, norh get info(index) <CR>
4.5.2

Beam Pattern

To obtain a beam pattern
IDL> beam=norh beam(index) <CR>
This is a 21 × 21 pixels array. To display this pattern (contour of half power beam width [HPBW])IDL> ocontour,beam,levels=[0.5] <CR>
8 34GHz synthesis is only available by program Hanaoka
9 Fujiki can synthesize only partial images. So it is necessary to give the center of the field-of-view.
10 This is because ’info’ data only contains the start and end times of a schedule but ’tsx’ data contains one by one

correspondence of frame number and observation time.

94.5.3

Coordinate gridTo overlay the coordinate gird on the image,
IDL> stepper, data(*,*,0), norh get info(index(0)) <CR>
IDL> norh grid, index(0) <CR>
To get the heliographic coordinate of the pointer
IDL> norh grid, index(0), /read out <CR>
4.5.4

Getting Information about Images

To get the observation time
IDL> print,fmt tim(index) <CR>
To get the image frequency
IDL> print,norh gt freq(index) <CR>
To get the circular polarization information
IDL> print,norh gt polariz(index) <CR>
To get the position of the image center in the coordinate in which the origin is the solar disk center andthe unit is arcsec
IDL> print,norh gt imgcen(index) <CR>
To get the roll of the image (usually zero)
IDL> print,norh cen(index,roll=roll) <CR>
To get the exposure duration of the image
IDL> print,norh gt expdur(index) <CR>

4.5.5

Using map procedure of the SolarSoftware

In order to coalign the NoRH image with those obtained by the other instruments, it is convinient to use
the map procedures made by Dr. D. Zarro (for detailed information, see
http://orpheus.nascom.nasa.gov/~zarro/idl/maps.html. The map of the NoRH image can be madeas follows:
IDL> norh index2map,index,data,map <CR>
IDL> plot map,map <CR>
4.5.6

Derivation of Flux Density (Fν ) from Brightness Temperature (Tb )An NoRH image indicate distribution of brightness temperature (unit K). To know the intensity (unit
SFU/sterad) from each pixel,
IDL> ﬁ=norh tb2ﬂux(data,index,/intensity) <CR>
The ﬂux density (unit SFU) of the whole image, the procedure is as follows.
IDL> ﬁ=norh tb2ﬂux(data,index) <CR>
The ﬂux density from the partial area of an image, i0 < i < i1 j0 < j < j1 is
IDL> box=[i0, i1, j0, j1] <CR>
IDL> ﬁ=norh tb2ﬂux(data,index,box=box) <CR>
or by giving the (x, y) coordinate (origin solar disk center; unit arcsec), for the area x0 ≤ x ≤ x1 andy0 ≤ y ≤ y1,
IDL> abox=[x0, x1, y0, y1] <CR>
IDL> ﬁ=norh tb2ﬂux(data,index,abox=abox) <CR>
4.5.7

Circular Polarization Degree

From a pair of (R+L) and (R–L) images of 17 GHz, distribution of circluar polarization degree can beobtained. It is used for judging the emission mechanism and/or deriving the magnetic ﬁeld strength. The
deﬁnition is;
(R−L)

rc ≡

(R−L)

Fν

Tb

Fν

Tb

=
(R+L)

10

(R+L)

Minimum is –1 (perfectly left-handed circular polarized), and maximum is +1 (perfectly right-handed
circular polarized). The procedure is :IDL> ﬁle=’./ipa990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexa,dataa <CR>
IDL> ﬁle=’./ips990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexs,datas <CR>
IDL> ﬁ17=norh tb2ﬂux(dataa,indexa,/intensity) <CR>
IDL> fv17=norh tb2ﬂux(datas,indexs,/intensity) <CR>
IDL> norh polariz,indexa,ﬁ17,indexs,fv17,indexp,pol,mvdp <CR>
pol is an array of rc . mvdp is an array including the values of unity (1) for valid data or zero (0) for
non-valid data. indexp is an index correspoinding to data pol.
4.5.8

Make the Size of Beams Same between Two Images

In order to analyze data of dual frequency observation, the size of the beams have to be made same before
taking ratio. The method is as follows,
IDL> norh rd img,ﬁle0,index0,data0 <CR>
IDL> norh rd img,ﬁle1,index1,data1 <CR>
IDL> norh convol,index1,index0,data0,index0c,data0c <CR>
By norh convol, data data0 is convolved by a beam associated with index1. The pixel size of the result
array data0c will become the coarser one between the beam and the image. Similarly,
IDL> norh convol,index0,index1,data1,index1c,data1c <CR>
then data0c and data1c have the same beam and the same pixel size.
4.5.9

Spectrum Distribution

From a pair of 17GHz and 34GHz images, spectrum distribution can be obtained. It is used for judging theemission mechanism and/or deriving the power-law index of non-thermal elecrons. The derived variable
is α whose deﬁnition isFν ∝ ν α
Since available frequencies for NoRH are only two, the actual derivation isα=log (Fν34GHz /Fν17GHz )log (34GHz/17GHz)

By using a pair of images of 17 GHz and 34 GHz with the same ﬁeld of view
IDL> ﬁle=’./ipa990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexa,dataa <CR>
IDL> ﬁle=’./ipz990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexz,dataz <CR>
IDL> ﬁ17=norh tb2ﬂux(dataa,indexa,/intensity) <CR>
IDL> ﬁ34=norh tb2ﬂux(dataz,indexz,/intensity) <CR>
IDL> norh convol,indexz,indexa,ﬁ17,indexa c,ﬁ17 c <CR>
IDL> norh convol,indexa,indexz,ﬁ34,indexz c,ﬁ34 c <CR>
IDL> norh alpha,indexa c,ﬁ17 c,indexz c,ﬁ34 c ,indexal,alpha,mvda <CR>
alpha is the power law index of spectrum α. mvda is an array including the values of unity (1) for valid
data or zero (0) for non-valid data. indexal is an index correspoinding to data alpha.
4.5.10Curves of Flux, Circular Polarization, and Spectrum Index from a Partial Area

In order to obtain curves of ﬂux, circular polarization degree, and spectrum index from a partial area ofa series of images,
IDL> abox=[23,35,33,41] <CR>
IDL> ﬁ17=norh tb2ﬂux(dataa,indexa,abox=abox) <CR>
IDL> fv17=norh tb2ﬂux(datas,indexs,abox=abox) <CR>
IDL> ﬁ34=norh tb2ﬂux(dataz,indexz,abox=abox) <CR>
IDL> norh polariz,indexa,ﬁ17,indexs,fv17,indexp,polariz,mvdp <CR>
IDL> norh alpha,indexa,ﬁ17,indexz,ﬁ34,indexal,alpha,mvda <CR>
11

Plot as, say,
IDL> utplot,indexp,polariz <CR>
IDL> utplot,indexal,alpha <CR>
4.5.11

Optically-Thin Non-Thermal Gyrosynchrotron Emission

Note: The procedures described in this subsection are under testing. Comments are welcome for improvement.
Based on approximation models, the relation between the physical variables of emitting region andthe emission can be derived. The electron distribution function is assumed to be the power law.
dN V (E)
=K
dE

(

E
E0

)−δ
。

where E is electron energy (keV), N V (E) is number of electrons (particles) that has larger energy thanE. This distribution is described with parameters δ, E0 , and K. But it is usual to use N V (E0 ) =K/(δ − 1)/E0δ−1 instead of K. And we ﬁx E0 = 10 keV after Dulk (1985).
(a) From Physical Variables to Emission
Inputs; power-law index δ, magnetic ﬁeld strength (G), angle between magnetic ﬁeld and line of sight(degree), and N V — total number (particles) of non-thermal electron (of E > 10 keV): Outputs; ﬂux
density (SFU), circular polarization degree:
By Dulk’s (1985) method:
IDL> dulk gysy,delta,bb,theta,nv,freq,ﬁ,rc <CR>
If the size of emitting source (by solid angle in unit of sterad) is given additionally, optical depth is also
obtained
IDL> dulk gysy,delta,bb,theta,nv,freq,ﬁ,rc,omega,tau <CR>
By Ramaty’s (1969) method:
IDL> ramaty gysy,delta,bb,theta,nv,freq,ﬁ,rc <CR>
IDL> ramaty gysy,delta,bb,theta,nv,freq,ﬁ,rc,omega,tau <CR>(b) From Emission to Physical Variables
Based on Dulk’s (1985) model we may derive the physical variables from emission. After deriving α(see 4.5.9), power law index of non-thermal electron distribution function is
IDL> norh alpha,indexa,ﬁ17,indexz,ﬁ34 ,indexal,alpha,mvda <CR>
IDL> norh alpha2delta,alpha,delta <CR>
If V-component (R−L) of 17 GHz is given adding to this, physical variables can be derived to someextent. For this, we have to assume one of three variables to be obtained — magnetic ﬁeld strength(G), angle between magnetic ﬁeld and line of sight (degree), and total number of non-thermal electron of
E > 10 keV (particles).
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,thetain,bb,nv,/assumetheta <CR>
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,bbin,nv,theta,/assumebb <CR>
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,nvin,theta,bb,/assumenv <CR>
Adding to this, if the size of emission source is given (as solid angle. Unit is sterad), optical thickness isderived
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,thetain,bb,nv,/assumetheta ,omega,tau <CR>
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,bbin,nv,theta,/assumebb ,omega,tau <CR>
IDL> norh gysy inv,ﬁ17,ﬁ34,delta,fv17,nvin,theta,bb,/assumenv ,omega,tau <CR>
Note: In case of images, make the size of beams same between two images (see section 4.5.8).
4.5.12

Optically-Thin Thermal Free-Free Emission

Note: The procedures described in this subsection are under testing. Comments are welcome for improvement.
Based on Dulk (1985)’s approximation model, the relation between the physical variables of emitting
region and the emission can be derived.
(a) From Physical Variables to Emission

12

0.1000

0.01000.00100.0001
00:00

02:00
04:00
Start Time (27-Aug-99 22:30:21)

06:00

Figure 1: Light curves (Correlation plot)

Inputs; electron temperature (K), line-of-site component of magnetic ﬁeld (G), and volume emission
measure (cm−3 ) Outputs; ﬂux density (SFU), circular polarization degree:
IDL> dulk frfr,te,b loc,vem,freq,ﬁ,rc <CR>
If the size of emitting source (by solid angle in unit of sterad) is given additionally, optical depth is also
obtained
IDL> dulk frfr,te,b loc,vem,freq,ﬁ,rc,omega,tau <CR>(b) From Emission to Physical Variables
Inputs; I-component (R+L) and V-component(R−L) of ﬂux density (SFU): Outputs; line-of-sight√component of magnetic ﬁeld (G), V EM/ Te where V EM is volume emission measure, Te is electron
temperature:
IDL> norh frfr inv,ﬁ,fv,b los,vem over sqrtte <CR>
If one of V EM or Te is assumed, the other is derived:
IDL> norh frfr inv,ﬁ,fv,b los,tein,vem,/assumete <CR>
IDL> norh frfr inv,ﬁ,fv,b los,vemin,te,/assumevem <CR>
Adding to this, if the size of emission source is given (as surface angle. Unit is sterad), optical thickness
is derived
IDL> norh frfr inv,ﬁ,fv,b los,tein,vem,/assumete,omega,tau <CR>
IDL> norh frfr inv,ﬁ,fv,b los,vemin,te,/assumevem,omega,tau <CR>

4.6

Example of Analysis Session

4.6.1

Choose an Event

Many interesting events are introduced in NoRP web site. It is recommended to access ﬁrst to thesepages. The URL is http://solar.nro.nao.ac.jp/norh/
4.6.2

Light Curves

After choosing an event for analysis, see the light curves. It is useful to plot the correlation instead of
the ﬂux density. The method is as follows (Fig 1).
IDL> norh rd tcx,’1999-8-28’,index,data <CR>
IDL> utplot,index,data,/ylog <CR>
Deﬁnition of ’correlation’ is ”averaged values of correlation of antenna pairs (after removing short baseline pairs) of NoRH”. Correlation increases as a strong microwave signal comes due to e.g. a ﬂare. So it isused instead of the real light curve (plot of ﬂux density). For 17 GHz plot, 1 % of correlation corresponds13

to 30 SFU ﬂux density. It is used because much computation resource is necessary for image synthesisthat is the only method to obtain ﬂux density at each time (see section 4.5.6). And correlation has anadvantage that it is almost not aﬀected by the weather condition. However, it does not increase when
the ﬂux is so strong because it has an upper limit of unity.
4.6.3

Image Synthesis

For the choosen event, synthesize images. Before this, search for the already synthesized images in our
FTP server since we prepare images for most of the important events. The URL is
ftp://solar-pub.nao.ac.jp/pub/nsro/norh/images. It can be reached by following the link in our
web page11 .
For the one who wants to synthesize by her/himself, do the following two sets of commands.
IDL> norh trans,[’1999-8-28 0:56:42’]<CR>
IDL> norh synth,[’1999-8-28 0:56:42’]<CR>
The former is for transfering the raw data ﬁle (ss17990828... including Fourier components andsz00990828... including ephemeris parameters) from NoRH data archive to the current directory. It
takes several minutes depending on the network condition. Please ignore the warning message ”No such
file or directory”. If the trasfer is successful, you have ﬁles named ss17990828027 (≈ 16 Mbyte)
and sz00990828001 (≈ 200 byte). The second command is the actual synthesis procedure and it takes
tens of seconds to a few minutes per an image. If it is successful, you will obtain ifa990828 005642 andifs990828 005642 in the current directory. These are the FITS ﬁles whose contents are NoRH (R+L)
and (R–L) images, respectively. For spectrum analysis, make also 34 GHz image,
IDL> norh trans,[’1999-8-28 0:56:42’],freq=34<CR>
IDL> norh synth,[’1999-8-28 0:56:42’],freq=34<CR>
Similarly, the raw data ﬁles (ss17990828... and sz00990828... are transformed and image FITS ﬁleifz990828 005642 is made. Note only (R+L) component for 34 GHz image.
4.6.4

Image Plot

Next, plot the images. We use a FITS ﬁle ipa990828 005642. This ﬁle contains ”an image of partial
Sun of 17 GHz (R+L) component at 00:56:42 UT on Aug 28, 1999”. To read
IDL> ﬁle=’./ipa990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexa,dataa <CR>
IDL> stepper,dataa,norh get info(indexa) <CR>
IDL> norh grid,indexa <CR>
Easy plot is (Fig 2)
IDL> norh plot,indexa,dataa <CR>
The unit of data is brightness temperature (K). Solar north is up.
For preparing to overplot with other instrumental data, change the data format to SolarSoftware map.
IDL> norh index2map,indexa,dataa,mapa <CR>
IDL> plot map,mapa,/cont,/grid <CR>
IDL> beam=norh beam(indexa,xbeam=xbeam) <CR>
IDL> contour,beam,!x.crange(0)+xbeam,!y.crange(0)+xbeam,/over,levels=[0.5] <CR>

4.6.5

Polarization Plot

From a pair of (R+L) and (R–L) images of 17 GHz, distribution of circluar polarization degree can beobtained. It is used for judging the emission mechanism and/or deriving the magnetic ﬁeld strength. The
deﬁnition is;
(R−L)

rc ≡

(R−L)

Fν

Tb

Fν

Tb

=
(R+L)

(R+L)

Minimum is –1 (perfectly left-handed circular polarized), and maximum is +1 (perfectly right-handed
circular polarized). The procedure is :11 They are under /nfs/nobeyama solar/pub/norh/images in SDAS.

14

NoRH 17GHz r+l 28-Aug-1999 00:56:43.232 UT
-400

beam

Pol(%)= -32768 -32768

Y (arcsecs)

-450

-500

-550

-600

1.e4 1.e5 1.e6 1.e7 1.e8
100

150

200
X (arcsecs)

250

300

Figure 2: 17GHz (R+L) image

NoRH 17GHz r+l 28-Aug-1999 00:56:43.232 UT
-400

beam

Pol(%)= 10 30 50 70 90

Y (arcsecs)

-450

-500

-550

-600

1.e4 1.e5 1.e6 1.e7 1.e8
100

150

200
X (arcsecs)

250

300

Figure 3: distribution of 17GHz circular polarization degree

15

NoRH alpha 28-Aug-1999 00:56:43.258 UT-400

Pol(%)= 10 30 50 70 90
Cont: Tb(17GHz)=1.e6

Y (arcsecs)

-450

-500

-550
delta=6

-600

5

4

-4
100

3

-2
150

thin

thick

0

2

200
X (arcsecs)

250

300

Figure 4: Spectrum Distribution (gray scale), Tb17GHz = 1MK (contour of thick line), and circular polarization degree (contour of thin line)

IDL> ﬁle=’./ips990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexs,datas <CR>
IDL> ﬁ17=norh tb2ﬂux(dataa,indexa,/intensity) <CR>
IDL> fv17=norh tb2ﬂux(datas,indexs,/intensity) <CR>
IDL> norh polariz,indexa,ﬁ17,indexs,fv17,indexp,pol,mvdp <CR>
pol is an array of rc . mvdp is an array including the values of unity (1) for valid data or zero (0) for
non-valid data. indexp is an index correspoinding to data pol. For easy plot (Fig 3)
IDL> norh plot,indexa,dataa,indexp,pol,mvdp <CR>
For preparing to overplot with other instrumental data, change the data format to SolarSoftware map.
IDL> norh index2map,indexp,pol*mvdp,mappol <CR>
IDL> plot map,mappol,/cont,levels=[-0.8,-0.4,-0.2,0.2,0.4,0.8] <CR>
4.6.6

Spectrum Distribution

From a pair of 17GHz and 34GHz images, spectrum distribution can be obtained. It is used for judging theemission mechanism and/or deriving the power-law index of non-thermal elecrons. The derived variable
is α whose deﬁnition isFν ∝ ν α
Since available frequencies for NoRH are only two, the actual derivation isα=log (Fν34GHz /Fν17GHz )log (34GHz/17GHz)

By using a pair of images of 17 GHz and 34 GHz with the same ﬁeld of view
IDL> ﬁle=’./ipa990828 005642’ <CR>
IDL> norh rd img,ﬁle,indexa,dataa <CR>
IDL> ﬁle=’./ipz990828 005642’ <CR>
16

Yes

Strong polarization (> sev.×10%), Bright even in quiet, above a sunspot ?
No
?
Yes

No

Tb17GHz > 1 MK ?

?

?
gyroresonance

?

α>0

α≤0

α>0

α≈0

α<0

?

?

?

?
opt-thinsynchrotron
non-therm δoropt-thinfree-freecoronal B?

opt-thicksynchrotron

opt-thinsynchrotron
non-therm δ

opt-thicksynchrotronor
opt-thickfree-free

opt-thinsynchrotron
non-therm δFigure 5: Chart for interpretation of emission mechanism from the spectrum distribution
IDL> norh rd img,ﬁle,indexz,dataz <CR>
IDL> ﬁ17=norh tb2ﬂux(dataa,indexa,/intensity) <CR>
IDL> ﬁ34=norh tb2ﬂux(dataz,indexz,/intensity) <CR>
IDL> norh convol,indexz,indexa,ﬁ17,indexa c,ﬁ17 c <CR>
IDL> norh convol,indexa,indexz,ﬁ34,indexz c,ﬁ34 c <CR>
IDL> norh alpha,indexa c,ﬁ17 c,indexz c,ﬁ34 c ,indexal,alpha,mvda <CR>
alpha is the power law index of spectrum α. mvda is an array including the values of unity (1) for valid
data or zero (0) for non-valid data. indexal is an index correspoinding to data alpha. For easy plot
(Fig 4)
IDL> norh plot alpha,indexal,alpha,mvda,indexp,pol,mvdp,indexa,dataa <CR>
For preparing to overplot with other instrumental data, change the data format to SolarSoftware map.
IDL> norh index2map,indexal,alpha*mvda,mapalpha <CR>
IDL> plot map,mapalpha,dmin=-4,dmax=2 <CR>
4.6.7

Interpretation of Data

The interpretation is done by using the chart in Figure 5. Physical information can be obtained whenthe emission is by ”optically-thin gyrosynchrotron” or by ”optically-thin free-free”. We can derive thevariable using the Dulk’s (1985) models.
In case ”optically-thin gyrosynchrotron” emission, we obtain power-law index of the non-thermal
electrons. Here we assume the distribution function of electrons to be( )−δE
dN V (E)=K.
dE
E0
where E is electron energy (keV), N V (E) is number of electrons (particles) that has larger energy thanE. This distribution is described with parameters δ, E0 , and K. But it is usual to use N V (E0 ) =K/(δ − 1)/E0δ−1 instead of K. And we ﬁx E0 = 10 keV after Dulk (1985). If we ﬁnd the emission to be”optically-thin gyrosynchrotron”, we will obtain δ from α by
δ = −1.1(α − 1.2).
17

In case ”optically-thin free-free” emission, we obtain line-of-sight component of coronal magnetic ﬁeld.
From the circular polarization degree rc ,(r )c
B ≈ 30G.
1%
For example, ﬁgure 4 can be interpreted as follows: First, the strong polarized source at (x, y) =(180, −520) is by gyroresonance. It may be conﬁrmed by comparing the image with optical magnetogram
to see if there is a sunspot. Next, the area inside the contour line of Tb17GHz = 1MK is emitting by
optically-thin gyrosynchrotron. Non-thermal power-law index δ is obtained from α immediately and we
see that the emission from two-sides of the loop structure is ’softer’ than that of the top. Next is forthe area where Tb17GHz < 1MK. Around (x, y) = (270, −500), it is hard to judge if it is ’optically-thingyrosynchrotron’ or ”optically-thin free-free” because α ≈ 0. If it is bright in soft X-ray it may be free-freeemission. In this case, line-of-sight component of coronal magnetic ﬁeld is obtained. Since the other area
has α > 0, it is optically thick and no information can be obtained.

4.7

Others4.7.1

Read Raw Data Directly

If the raw data is installed under directory ${NORH}/rawd in order to read raw data directly,
IDL> norh rd rdt,st time,ed time,rdata,header <CR>
for 34 GHz
IDL> norh rd rdt,st time,ed time,rdata,header,freq=34 <CR>
To read the raw data after copying to the current directory,
IDL> norh rd rdt,st time,ed time,rdata,header,dir raw=’.’ <CR>
To read by giving ﬁle name
IDL> norh rd rdt17,ﬁle,rdata,header <CR>
IDL> norh rd rdt34,ﬁle,rdata,header <CR>
For obtaining observing time (JST)IDL> timej=norh rdt2timej(rdata) <CR>
4.7.2

Antenna/Antenna-Pair ID and Name

Each NoRH antenna has its own ID number and name. The correspondance is
IDL> antname=norh antnum2name(indgen(84)) <CR>
The inverse is
IDL> antnum=norh antname2num([’n15’,’w01’]) <CR>
Each NoRH anttena-pair pair has its own ID number. The correspondance of this number and the namesof anttennas of this pair is given by
IDL> ant=norh pair2ant(indgen(84*83/2)) <CR>
The inverse is
IDL> pair=norh ant2pair([0,28]) <CR>
4.7.3

Sun Position at Nobeyama

The azimuth and elevation of the Sun at Nobeyama is obtained by
IDL> norh t2azel,time,az,el <CR>
Unit is degree.
4.7.4

Make original SZ ﬁle

For making original SZ ﬁle by some reason,
IDL> norh mksz,date <CR>
For unusing some data obtained by some paticular antenna from synthesis procedure, make a new SZ ﬁleIDL> norh mksz,date,[’n1’,’e10’] <CR>
In this example, data of antenna N01 and E10 are unused.

18

5

Analysis without IDL

It is described in this section how to analyse the NoRH data without IDL. This is based on the UNIX
commands, C-shell scripts and free astronomy softwares such as AIPS, IRAF etc.

5.1

Data Base

The observation time (info), logs (lob), event lists (evx) are recorded in ASCII text ﬁles. you can readthem directly by using any editor softwares. The detailed explanation of each ﬁle is given in Appendix
A.

5.2

Time-series data and Images

Time-series averaged correlation (tcx, tsx) and images (ifx, ipx) are both recorded as FITS format ﬁles.
You can read them by using popular free astronomy softwares such as AIPS, IRAF etc.

5.3

Image data

5.3.1

Image Files at NoRH Data Archive

Some synthesized images (Table 1) are put in the NoRH data archive (See Section C). You can obtainthem by anonymous FTP. Before synthesizing by yourself, try them ﬁrst.
5.3.2

Transfer of raw data

You have to transfer the raw-data and ’SZ’ ﬁles (Appendix A.3 and A.4) from NoRH data archive(Appendix C) to your computer through the network before synthesis of the NoRH images. It is convenient
to use the norh trans command for this purpose. This is a C-shell script that can be run on any UNIXmachine. Or you can directly log in the SDAS anonymous FTP server.
(1) By using norh transAfter editing the input ﬁle (say input) adequately
unix% norh trans input <CR>
The raw data ﬁles as well as corresponding ’SZ’ ﬁles will be transfered. The format of the input ﬁle is asfollows:
ss17980214006
ss34980214006
ss17920812002 b
se17990216085759# 17GHz# 34GHz# schedule b# event

One line corresponds to one raw-data ﬁle. For steady-mode data that has multiple schedules (Appendix
A.2),(ﬁle name) (schedule ID)
The explanation for schedule and names of ﬁles are given in Appendix A.
(2) By logging in to anonymous FTP server
You can get the data by logging in to the FTP server,
unix% ftp solar-pub.nao.ac.jp <CR>
The NoRH raw-data is put in the directory /pub/nsro/norh/raw. Do not forget to retrieve the ’SZ’ ﬁlefor corresponding day.
5.3.3

Image synthesis

This package has three programs for synthesis, See table 2 for supporting data. Detailed description foreach program is given in Section 6.
Note ! All the synthesis programs are written in Fortran 77 (partially 90). The C-shell scripts describedin this section call externally the executive binaries of these programs. We prepared the binaries for Intelx86 with LinuxOS architectures in this package. So it is possible to synthesize the NoRH package on
machines with these architecture. If you run on other, it is necessary to compile them by yourself (Youhave to purchase commercial numerical library in this case. See section 6 for detail.).
19

It is convenient to use the norh synth command for synthesis. This is a C-shell script that can be
run on any UNIX machine. After editing the input ﬁle (say input)
unix% norh synth input <CR>
The format of input ﬁle is dependent on what synthesis program is used. See section 6 for detailed
information.
The default program is Hanaoka for 17GHz data. For 34GHz data,
unix% norh synth -p hanaoka34 input <CR>
For using Fujiki,
unix% norh synth -p fujiki17 input <CR>
For using Koshix,
unix% norh synth -p koshix17 input <CR>20

Table 2: Summary of synthesis programs

Hanaoka
Koshix
Fujiki

Supported data [Yes/No]
17/34GHz Steady/Event Full/Part
Y/Y
Y/Y
Y/Y
Y/N
Y/Y
Y/Y
Y/N
Y/Y
–/Y

Hanaoka
Koshix
Fujiki6

Pixel Size [arcsec]
17GHz
34GHz
4.9
2.45
4.9
–
2.45
–

Field of View [pixel]
17GHz
34GHz
≤ 512
≤ 1024
≤ 512
–
128
–

Note
good at ﬂares, no-good at diﬀuse sources
good at diﬀuse faint sources, no-good at ﬂares
high-spatial resolution synthesis of compact sources

Detailed Description of Synthesis Programs

The standard NoRH synthesis programs, Hanaoka, Koshix, Fujiki are explained in this section (table 2).
The executable binary ﬁles are given for Intel x86 with LinuxOS architectures in this package. Compile
procedure will be necessary if you run these programs on others. See section 6.4 (You may have topurchase commercial numerical libraries).

6.1

HanaokaThis is the most basic program for synthesis. It applies the CLEAN algorithm to the point sources on
the images and is good at analysis of ﬂares. On the other hand, it is not good at diﬀuse sources.
Present version
ver. 6.2
Supported computer architectureIntel x86 with LinuxOS, NEC/SX
Supported data
17GHz/34GHz, Steady/Event, Full/Partial Sun
Pixel Size
4.9 arcsec/pixel (17GHz), 2.45 arcsec/pixel (34GHz)
Field of View
Under 512 pixels for 17GHz. Under 1024 pixels for 34GHz.
How to use(1)
unix% hanaoka17 < input17(2)
unix% norh synth -p hanaoka17 input(3)
IDL> norh synth,time,prog=’hanaoka’,freq=17(4)
unix% hanaoka34 < input34(5)
unix% norh synth -p hanaoka34 input(6)
IDL> norh synth,time,prog=’hanaoka’,freq=34

21

Example of input ﬁle
The line numbers are given for convinience. The item with (*) usually do not have to be changed. A
template is given in ${NORH}/soft/synthesis/hanaoka.
17GHz
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:

.
ss17980419
sz00980419001
512
1,0,0
1
3600
600
1
1
-0.5,-0.5
0.01; output directory; raw-data ﬁle name
; ’SZ’ ﬁle name; FOV pixel size
; image center oﬀset from Sun center; start frame number; end frame number; frame interval; *number of integration frames for calibration; *number of integration frames for synthesis; *CLEAN criterion 1 (R+L), (R-L); *CLEAN criterion 2

1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:

.
ss34980419
sz00980419001
1024
1,0,0
1
3600
600
1
1
-1
0.01

; output directory; raw-data ﬁle name
; ’SZ’ ﬁle name; FOV pixel size
; image center oﬀset from Sun center; start frame number; end frame number; frame interval; *number of integration frames for calibration; *number of integration frames for synthesis; *CLEAN criterion 1; *CLEAN criterion 2

34GHz

Explanation for each item
(line 1) output directory(line 2) raw-data ﬁle name
In case of steady-mode data, give only ssFFYYMMDD where FF is frequency (17 or 34), YYMMDD
is the date of observation. Do not give full ﬁle name like ssFFYYMMDD### where ### is the ﬁlenumber. That is automatically calculated from the given frame. In case of event-mode data, give full ﬁlename.
(line 3) ’SZ’ ﬁle name
’SZ’ ﬁle name corresponding to the date of the raw-data ﬁle.
(line 4) pixel size of the ﬁeld of view
A square region with pixel size given in this line will be the ﬁeld of view of the syntehsized image. Incase of 17GHz data, the full Sun image is 512-pixel square, and in case of 34GHz data, that is 1024-pixel
square. Pixel size is 4.9 (2.45) arcsec for 17GHz (34GHz).
(line 5) image center oﬀset from Sun center
Give non-zero values if you synthesize an image with the center that has an oﬀset from the Sun center.
The ﬁrst element indicates the unit of shift, arcsec if 1, pixel if 2. If you do not want to get a shifted
image, just give ’1,0,0’.
(line 6) ﬁrst frame to synthesize
Give zero in case of non-uniform interval.
(line 7) last frame to synthesize
Give number of frames in case of non-uniform interval.
(line 8) frame interval
Give frame numbers in case of non-uniform interval. If it’s too long, give in multiple lines.
(line 9) number of intergration frames for calibration
22

(line 10) number of intergration frames for synthesis(line 11) CLEAN criterion 1
Continue CLEAN until the maximum of the dirty map will become this value. The unit is brightness
temperature (steady solar disk is 10000 K). The criterion that is given in the next item (line 12) will be
adopted if it is larger than this value. If given values are negative, the absolute value of them times thedisk brightness would be adopted as the criterion. For 17GHz data, give values for (R+L) and (R-L),
the recommended values are -0.5 and -0.5, respectively. For 34GHz data, give value only for (R+L), therecommended value is -1.
(line 12) CLEAN criterion 2
This given value times the maximum of the dirty map will become the other criterion for CLEAN
algorithm. The criterion given in the previous item (line 11) will be adopted if it is larger than this value.
The recommended value is 0.01. It is safer to give larger value for poor S/N data.

23

6.2

KoshixThis program is based on the Steer algorithm. It applies the CLEAN method to the diﬀuse sources on
the images and is good at analysis of the quiet Sun and ﬁlaments. On the other hand, it is not good atﬂares.
Present version
ver. 6.2
Supported computer architectureIntel x86 with LinuxOS, NEC/SX
Supported data
17GHz (non-support for 34GHz), Steady/Event, Full/Partial Sun
Pixel Size
4.9 arcsec/pixel
Field of View
Under 512 pixels.
How to use(1)
unix% koshix17 < input17(2)
unix% norh synth -p koshix17 input(3)
IDL> norh synth,time,prog=’koshix’,freq=17
Example of input ﬁle
The line numbers are given for convinience. The item with (*) usually do not have to be changed. A
template is given in ${NORH}/soft/synthesis/koshix.
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:

.
ss17980419
sz00980419001
512
1,0,0
1
3600
600
1
1
3000,3000; output directory; raw-data ﬁle name
; ’SZ’ ﬁle name; FOV pixel size
; image center oﬀset from Sun center; start frame number; end frame number; frame interval; *number of integration frames for calibration; *number of integration frames for synthesis; *CLEAN criterion (R+L), (R-L)

Explanation for each item
(line 1) output directory(line 2) raw-data ﬁle name
In case of steady-mode data, give only ssFFYYMMDD where FF is frequency (17 or 34), YYMMDD
is the date of observation. Do not give full ﬁle name like ssFFYYMMDD### where ### is the ﬁlenumber. That is automatically calculated from the given frame. In case of event-mode data, give full ﬁlename.
(line 3) ’SZ’ ﬁle name
’SZ’ ﬁle name corresponding to the raw-data ﬁle.
(line 4) pixel size of the ﬁeld of view
A square region with pixel size given in this line will be the ﬁeld of view of the syntehsized image. Incase of 17GHz data, the full Sun image is 512-pixel square, and in case of 34GHz data, that is 1024-pixel
square. Pixel size is 4.9 (2.45) arcsec for 17GHz (34GHz).
(line 5) image center oﬀset from Sun center
Give non-zero values if you synthesize an image with the center that has an oﬀset from the Sun center.
The ﬁrst element indicates the unit of shift, arcsec if 1, pixel if 2. If you do not want to get a shifted
image, just give ’1,0,0’.
(line 6) ﬁrst frame to synthesize
Give zero in case of non-uniform interval.
(line 7) last frame to synthesize
Give number of frames in case of non-uniform interval.
(line 8) frame interval
Give frame numbers in case of non-uniform interval. If it’s too long, give in multiple lines.
(line 9) number of intergration frames for calibration(line 10) number of intergration frames for synthesis
24

(line 11) CLEAN criterion 1
Continue CLEAN until the maximum of the dirty map will become this value. The unit is brightness
temperature (steady solar disk is 10000 K). For 17GHz data, give values for (R+L) and (R-L), therecommended values are 3000 and 3000, respectively.

25

6.3

Fujiki

It is possible to analyze the ﬂare images in detail with this program because it synthesizes the compact
sources with a narrow beam by emphasizing the power of the higher wavenumber components. This
program always outputs the partial Sun images.
Present version
ver. 6.2
Supported computer architectureIntel x86 with LinuxOS, NEC/SX
Supported data
17GHz (non-support for 34GHz), Steady/Event, Partial Sun
Pixel Size
2.45 arcsec/pixel
Field of View
128 pixels ﬁxed.
How to use(1)
unix% fujiki17 < input17(2)
unix% norh synth -p fujiki17 input(3)
IDL> norh synth,time,prog=’fujiki’,freq=17
Example of input ﬁle
The line numbers are given for convinience. The item with (*) usually do not have to be changed. A
template is given in ${NORH}/soft/synthesis/fujiki.
1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:

.
ss17980419
sz00980419001
1,0,0
1
3600
600
1
1
10
1
1
10000,10000
10000,10000
0.01; output directory; raw-data ﬁle name
; ’SZ’ ﬁle name; image center oﬀset from Sun center; start frame number; end frame number; frame interval; *number of integration frames for calibration; *number of integration frames for synthesis; reference frame number; *num. of integ. frames for calibration of reference; *num. of integ. frames for synthesis of reference; *CLEAN criterion 1 (R+L), (R-L); *CLEAN criterion 2 (R+L), (R-L); *CLEAN criterion 3

Explanation for each item
(line 1) output directory(line 2) raw-data ﬁle name
In case of steady-mode data, give only ssFFYYMMDD where FF is frequency (17 or 34), YYMMDD is the dateof observation. Do not give full ﬁle name like ssFFYYMMDD### where ### is the ﬁle number. That is
automatically calculated from the given frame. In case of event-mode data, give full ﬁle name.
(line 3) ’SZ’ ﬁle name
’SZ’ ﬁle name corresponding to the raw-data ﬁle.
(line 4) image center oﬀset from Sun center
Give non-zero values if you synthesize an image with the center that has an oﬀset from the Sun center.
The ﬁrst element indicates the unit of shift, arcsec if 1, pixel if 2. If you do not want to get a shifted
image, just give ’1,0,0’.
(line 5) ﬁrst frame to synthesize
Give zero in case of non-uniform interval.
(line 6) last frame to synthesize
Give number of frames in case of non-uniform interval.
(line 7) frame interval
Give frame numbers in case of non-uniform interval. If it’s too long, give in multiple lines.
(line 8) number of intergration frames for calibration(line 9) number of intergration frames for synthesis(line 10) frame number of reference frame26

(line 11) number of intergration frames for calibration of reference frame(line 12) number of intergration frames for synthesis of reference frame(line 13) CLEAN criterion 1
Continue 1st CLEAN until the maximum of the dirty map will become this value. The unit is brightness
temperature (steady solar disk is 10000 K). For 17GHz data, give values for (R+L) and (R-L), therecommended values are 10000 and 10000, respectively. The criterion that is given in the next item (line15) will be adopted if it is larger than this value.
(line 14) CLEAN criterion 1
Continue 2nd CLEAN until the maximum of the dirty map will become this value. The unit is brightness
temperature (steady solar disk is 10000 K). For 17GHz data, give values for (R+L) and (R-L), therecommended values are 10000 and 10000, respectively. The criterion that is given in the next item (line15) will be adopted if it is larger than this value.
(line 15) CLEAN criterion 2
This given value times the maximum on the dirty map will become the other criterion for CLEAN
algorithm. The criterion given in the previous item (line 13) will be adopted if it is larger than this value.
The recommended value is 0.01.

6.4

Compilation of synthesis programs

All the synthesis programs are written in Fortran 77 (partially 90). The executable binary ﬁles are given
for Intel x86 with LinuxOS, Sun/Sparc, NEC/EWS, NEC/SX architectures in this package. Compile procedure that is explained in this section will be necessary if you run these programs on other architectures.
You may have to purchase commercial numerical libraries.
(1) install numerical libraries
Get and install the following numerical libraries.
Fujitsu/SSLII
NEC/ASLCommercial
Commercial

http://www.fujitsu.co.jp/
http://www.nec.co.jp/

Note ! NEC/ASL is necessary only to compile on NEC/SX or NEC/EWS.
(2) install the FITSIO library
Get and install the I/O library for FITS format data fromhttp://legacy.gsfc.nasa.gov/docs/software/fitsio/(3) compile HeliogLib
Compile and create library under ${NORH}/soft/helioglib/ver6.2.
(4) compile the synthesis programs
Compile the programs under ${NORH}/soft/synthesis.

27

Table 3: NoRH data
pre-ﬁxss17,ss34
se17,se34
sz00
ifa,ifs,ifr,iﬂ,ifz
ipa,ips,ipr,ipl,ipz
info
rlphdif
tsa,tsz
tca,tcz
eva,evzlob
repcontents
raw data (steady mode)raw data (event mode)’SZ’ data
Full Sun Image
Partial Sun Imageobservation time
R/L phase diﬀerence
averaged correlation
averaged correlation (only R+L)
event list
observation log (antenna conditions etc.)
tohban report

directory
anywhere [raw/steady]anywhere [raw/event]anywhere [raw/steady,data/sz update]anywhere [images]
anywhere [images]
data/info
data/rlphdif
data/tsx
data/tcx
data/evx
data/lob
data/rep[ ] : at the NoRH data archive
Table 4: abreviation marks used for ﬁle names
YY
MM
DD
HH
MN
SS
LLL
###
S

A

last two digits of year
month
day
hour
minutesecondmilli-second
sequential number
schedule ID

NoRH data

In this section, the NoRH data is explained in detail (Table 3). We use marks that are explained in Table
4.

A.1

Observation mode of NoRH

Basically there are two modes of NoRH data recording. In the steady mode, the raw data is recorded asa frame after 1-sec integration. One raw-data file has 600 frames (i.e. 600 sec) each and is named with asequential number. In the event mode, the raw data is recorded as a frame after 50 milli-seconds (before
September 1995) or 100 milli-seconds (after October 1995) integration. The event data is recorded whena ﬂare-event occurs on the Sun. One event-mode file corresponds to one ﬂare-event and has almost no
limitation on number of frames.

A.2

What is Schedule for NoRH ?

The unit of NoRH observation is called schedule. In principle, one day has one schedule. But when sometrouble happens to the observing system, there may be multiple schedules. The schedule ID is given to
identify each schedule. They are ”date + an alphabet letter”. That may be only ”date” if there is only
one single schedule per day. For example, the schedule ID on July 10, 1992 is ”920710” because there wasonly one schedule on that day. On the other hand, there were two schedules ”920712a” and ”920712b”
on July 12.

28

A.3

Raw data (ss17,ss34,se17,se34)

File namess17YYMMDD###
steady mode, 17GHz
ss34YYMMDD###
steady mode, 34GHz
se17YYMMDDHHMNSS event mode, 17GHz
se34YYMMDDHHMNSS event mode, 34GHz
The HHMNSS part in the event data ﬁle name is the start time of the event.
Unit of storage
Steady-mode raw data is processed one ﬁle per 600 frames (600 seconds), and event-mode is one ﬁleper one event.
Directory
Anywhere. In NoRH archive, they are put under raw.

A.4

’SZ’ data (sz00)

The ﬁles that contains information on ephemeris and valid antennas. (1) Ephemeris data: solar declination
δ (in arc-degree), hour angle (in time-sec), apparent solar radius (in arc-sec), solar p-angle (in arc-degree),solar b-angle (in arc-degree) at JST noon for previous, present, next days. (2) Valid antenna: In theorder of N01 – N28, E28 – E01, and W01 – W28. 0: use when synthesis, 1: unuse.
File namesz00YYMMDD001
Unit of storage
One ﬁle per one day
Directory
Anywhere. In NoRH archive, they are put under raw/steady. This ﬁle may be updated if sometrouble on antennas is found later. In this case, the ﬁle will be put in data/sz update.

A.5

Images (ifa,ifs,ifz,ipa,ips,ipz)

FITS format ﬁles that contain the NoRH images. See Appendix B for the detailed description for the
FITS headers, The unit of intensity in the image is brightness temperature in Kelvin.
File nameSteady mode
ifaYYMMDD HHMNSS
ifsYYMMDD HHMNSS
ifzYYMMDD HHMNSS
ipaYYMMDD HHMNSS
ipsYYMMDD HHMNSS
ipzYYMMDD HHMNSSEvent mode
ifaYYMMDD HHMNSS.LLL
ifsYYMMDD HHMNSS.LLL
ifzYYMMDD HHMNSS.LLL
ipaYYMMDD HHMNSS.LLL
ipsYYMMDD HHMNSS.LLL
ipzYYMMDD HHMNSS.LLL
Exampleifa981123 020533
ipz981123 020533.824

Full Sun

17GHz

Partial

34GHz
17GHz
34GHz

Full Sun

17GHz

Partial

34GHz
17GHz
34GHz

(R+L)
(R−L)
(R+L)
(R+L)
(R−L)
(R+L)

(R+L)
(R−L)
(R+L)
(R+L)
(R−L)
(R+L)

Full-Sun, 17GHz, R+L, Steady 1998-11-23 2:5:33 UTPartial, 34GHz, R+L, Event 1998-11-23 2:5:33.824 UT

Directory
Anywhere. We have daily images, 10min-interval images, event images (maximum averaged correlation> 1.5%) under images in NoRH archive. The synthesis of a raw data ﬁle ( e.g., ss17... ) results in theseimage ﬁles (e.g. ifa... and ifs... ).
29

A.6

Observation Time (info)

This is an ASCII-text ﬁle that contains the observation time, and its corresponding frame number.
File name
infoYYMMs steady
infoYYMMe event
Unit of storage
One ﬁle per one month
Directorydata/info
Example of Contents
s99030108001 ss17990301001 990301 080023 140022 000001 021600 TRACK
s99030108001 sz00990301001
s99030108002 ss17990301037 990301 140023 151458 021601 026076 TRACK
s99030108002 ss34990301001 990301 080023 151458 000001 026076 TRACK
s99030108002 sl00990301001
s99030108002 sz00990301001

The 1st, 3rd, and 4th lines are the records for raw-data ﬁles and the 2nd and 6th lines are for ’SZ’ﬁles. From the left: The volume ID of the master CD-ROM for this data, the ﬁrst ﬁle name of thesequence of raw-data ﬁles, observing date, the time (JST) of the ﬁrst frame in the corresponding dataﬁle, that of the last frame, ID number of the ﬁrst frame, that of the last frame, and the recording mode
(TRACK means the ordinary observation sequence). In this example, it means that the data of 1999-3-1
is contained in the CD-ROM s99030108001 and s99030108002. From the 1st to the 36th ﬁle are in
CD-ROM s99030108001. These ﬁles include frame 1 to 21600 that correspond to the data from 8:00:23
JST to 14:00:22 JST. The CD-ROM s99030108002 has the data from 14:00:23 JST to 15:14:58 JST.
Each of these CD-ROMS has its own sz00990301001 ﬁle.

A.7

R/L phase diﬀerence (rlphdif )There are 3 ﬁles. Each ﬁle is valid for the following term(s). These ﬁles are used in the older version ofsynthesis programs. In the newest version of synthesis programs, these are no longer necessary. But for
C2FITS program, still necessary.
ﬁlesun0628rlphdif
s971101rlphdif
sun0706 2rlphdif

valid term
– 1992-6-28
1997-10-30 – 1997-11-06
1998-01-21 – 1998-01-26
all days other than above

File namesYYMMDDrlphdif
Unit of storage
non-periodically
Directorydata/rlphdif

A.8

Averaged correlation (tsa,tsz)

This FITS ﬁle contains: 1) exact time of observation, 2) correlation averaged over the antenna pairs (maxis 100%), (R+L) & (R−) components for 17GHz, (R+L) for 34GHz. 3) observation status, 4) intensity.
See Appendix B for the detailed description for the FITS header,
File nametsaYYMMDDS
17GHz SteadytszYYMMDDS
34GHz Steady
tsaYYMMDD HHMNSS 17GHz EventtszYYMMDD HHMNSS 34GHz Event
The HHMNSS part of event data is the start time of the event.
Unit of precess

30One ﬁle per one schedule/event
Directorydata/tsx

A.9

Averaged correlation Digest (tca,tcz)

This FITS ﬁle contains: correlation averaged over the antenna pairs (max is unity). Only (R+L) components. See Appendix B for the detailed description for the FITS header,
File nametcaYYMMDDS
17GHz SteadytczYYMMDDS
34GHz Steady
tcaYYMMDD HHMNSS 17GHz EventtczYYMMDD HHMNSS 34GHz Event
The HHMNSS part of event data is the start time of the event.
Unit of storage
One ﬁle per schedule/event
Directorydata/tcx

A.10

Event list (eva,evz)

ASCII-text ﬁles that contains the lists of events (ﬂares).
File nameevaYYMM 17GHz
evzYYMM 34GHz
Unit of storage
One ﬁle per one month
Directorydata/evx
Example1

1999-04-01

23:00:47

23:11:24

23:02:42

637

23

17.7

0.6 22/ 19

From the left: Sequential number, date, start (UT), end (UT), peak (UT), duration (sec), max.
averaged correlation × 32768 and so on. In this example, there was an event with peak correlation of
23/32768 ≈ 0.007 = 0.7% at 23:02:42 UT with duration of 637 seconds.

A.11

Observation log (lob)ASCII-text ﬁles that contain useful information for data analysis, e.g., antenna conditions, weather, etc.
File namelobYYMM
Unit of storage
One ﬁle per a month
Directorydata/lob
Example### 99/03/10
Due to an ice sticked to 84 antenna dishes, data quality is
not good during the following times (before the sun shined
and melt the ice):Mar. 10, 00:00 UT - Mar.10, 02:30 UT.

A.12

Tohban report (rep)Observing tohban’s (duty observer) weekly reports that has brief description on Solar activity, signiﬁcant
events on that week.
File name
repYYWW
31

Unit of storage
one ﬁle per one week
Directorydata/rep

A.13

Sun tracking table (track table)

Information for tracking the Sun at Nobeyama. They are obtained by using the ephemeris data andthe latitude/longitude of Nobeyama. The contents are solar declination δ (in arc-degree), hour angle (intime-sec), apparent solar radius (in arc-sec), solar p-angle (in arc-degree), solar b-angle (in arc-degree) at
JST noon.
File nametrack tableYY.dat
Unit of storage
one ﬁle per one year
Directorydata/ephe

B

NoRH FITS header

In this section, the regulation of the FITS header that is adopted by NoRH data is given. This is usedin the ﬁles of image (ifx, ipx), and averaged correlation (tcx, tsx).

B.1

Header Regulation(1) Needed Part
• The keywords for standard FITS
The keywords below must appear in all FITS ﬁles and have a ﬁxed format.
SIMPLE : ’T’ if the ﬁle subjects to the FITS regulation
BITPIX : number of bits and type of the data
NAXIS
: number of dimensions of the data
NAXIS1 : number of pixels in x-axis
NAXIS2 : number of pixels in y-axis• Basic information for NoRH data
The keywords bellow should appear in all FITS ﬁles related to NoRH data.
◦ Information on observation time
STARTFRM : the ﬁrst IDs of used frames
ENDFRM: the last IDs of used frames
JST-STRT : the start time (JST) of integration for STARTFRM
JST-END: the end time (JST) of integration for ENDFRM
JST-TIME : exact middle time (JST) between the JST-STRT and JST-END
JST-DATE : the date (JST) for JST-STRT. The format is yyyy-mm-dd
STRT-OBS : UT for JST-STRT
END-OBS: UT for JST-END
TIME-OBS : UT for JST-TIMEDATE-OBS : UT for JST-DATE◦ Information of data contents
OBJECT: ﬁxed to sun
TELESCOP : ﬁxed to radioheliograph
ORIGIN: ﬁxed to nobeyama radio obs
POLARIZ: choose from rcp, lcp, r+l, r-l, l-r, r|l, (r-l)/(r+l), unknown
ATT-10DB : choose from 00dB, 10dB
OBS-MODE : choose from fix, alt
OBS-FREQ : choose from 17GHz, 34GHz
FRM-STAT : choose from 1-sec obs, event, calib
DATA-TYP : brief description of data type, e.g. cleaned map
32◦ Information of FITS header version
FITS header version. Now the newest is ver 2.0
HDRIDENT : ’HeliogFITS 2.0’
(2) Ephemeris
The keywords bellow should appear in NoRH image ﬁles. These are necessary for obtaining theheliographic coordinates or the beam patterns. They are not only the parameters determined from thedate and time, but also those local to the Nobeyama site.
SOLR: apparent radius of the solar disk
SOLP
: polar angle of the sun
SOLB: the heliographic latitude of the solar disk centerDEC: declination of the Sun at Nobeyama
HOURA: hour angle of the Sun at Nobeyama
AZIMUTH: azimuthal angle of the Sun at Nobeyama
ALTITUDE: altitude of the Sun at Nobeyama
ZANGLE: zenith angle of the Sun at Nobeyama
PMAT1/2/3/4 : transformation matrics between the antenna coordinates (on the geosphere:
antenna north is up) and the solar-disk coordinates (on the celestial sphere:
solar-north is up)

33

(3) Image coordinates
The keywords bellow should appear in NoRH image ﬁles in order to co-align them with images
obtained at other frequencies. They are basically regulated by the FITS standard.
CTYPE1 / CTYPE2:
type of coordinate axis. Usually ’solar-west’ and ’solar-north’, respectively. The
origin is at the solar disk center.
CDELT1 / CDELT2: size of pixel in arcsec
CRVAL1/CRVAL2/CRPIX1/CRPIX2:
The coordinate value of center of the CPIX1th pixel equals to the CRVAL1 in coordinate
CTYPE1. That’s same for ’...2’. The NoRH standard is
CRVAL1 = 0.00 (ﬁxed)
CRVAL2 = 0.00 (ﬁxed)
CRPIX1 = ’x’ of the pixel for the solar disk center in the image
CRPIX1 = ’y’ of the pixel for the solar disk center in the image
In case of partial images (ipx), CRVAL1 and CRVAL2 may be larger than the size ofthe image or may have negative values.
Note that, in the FITS regulation, the center of the pixel is the origin of the position. Be careful when
you try to coalign with the image described with a coordinate which has its origin at the edge of the pixel.
The distance (in arcsec) of the image center from the Solar disk center is given as
x-oﬀset = (NAXIS1/2+0.5-CRPIX1)*CDELT1+CRVAL1
y-oﬀset = (NAXIS2/2+0.5-CRPIX2)*CDELT2+CRVAL2(4) Parameters for each synthesis program
Parameters for synthesis should be given in order to make it possible to re-synthesize with these.
Although they may be diﬀferent from one program to another, some keywords are common. They may
be input parameters for synthesis◦ what program is used for synthesis,◦ parameters for calibration (e.g. used frame ID),
◦ parameters for synthesis itself, (CLEAN parameters etc.)
and output on synthesis◦ value of an indicator variable for CLEAN results.
The following keywords are recommended to be included at least.
PROGNAME : The format is arbitrary
NFRCAL: number of frames used for calibration
CRITER: CLEAN criterion
SOLR-FAC : ratio of the radio to optical solar disk radius
MBEAMC: main beam correction
NCOMPO: number of CLEAN conponents
DDOFF1: x-oﬀset of the center of the dirty solar disk
DDOFF2: y-oﬀset of the center of the dirty solar disk
DSKBR
: brightness of the dirty solar disk
BUNIT
: unit of the intensity of the image, usually brightness temperature in Kelvin (K).
(5) Others
Other keywords could be added.

B.2

Example of Header(1) Needed Part
• The keywords for standard FITS
SIMPLEBITPIXNAXISNAXIS1NAXIS2=====

T / file does conform to FITS standard-32 / number of bits per data pixel
2 / number of data axes
512 / length of data axis
1
512 / length of data axis
234

• Basic information for NoRH data
◦ Information on observation time
DATE-OBS= ’1998-05-09’/
TIME-OBS= ’03:20:23.754’/
STRT-OBS= ’03:20:21.254’/
END-OBS = ’03:20:26.254’/
JSTDATE = ’1998-05-09’/
JSTTIME = ’12:20:23.754’/
JST-STRT= ’12:20:21.254’/
JST-END = ’12:20:26.254’/
STARTFRM=
16499 /ENDFRM =16503 /◦ Information of data contents
POLARIZ = ’r+l’/
ATT-10DB= ’00dB’/
OBS-MODE= ’alt’/
OBS-FREQ= ’17GHz’/
FRM-STAT= ’1-sec obs’/
DATA-TYP= ’cleaned_map’/
OBJECT = ’sun’/
TELESCOP= ’radioheliograph’/
ORIGIN = ’nobeyama radio obs’ /◦ Information of FITS header version
HDRIDENT= ’HeliogFITS 2.0’/

(2) Ephemeris
SOLR
=
SOLP
=
SOLB
=
DEC
=
HOURA
=
AZIMUTH =ALTITUDE=ZANGLE =
PMAT1
=
PMAT2
=
PMAT3
=
PMAT4
=

952.22 / optical solar radius (arcsecond)-22.5235 / solar polar angle (degree)-3.3307 / solar b0 (degree)
17.2807 / declination (degree)
2270.83 / hour angle (second)
27.7610 / azimuth (degree)
70.3056 / altitude (degree)
23.5280 / zenithangle (degree)
0.98640 / projection matrix
0.09448 / projection matrix-0.04883 / projection matrix
0.94981 / projection matrix(3) Image coordinates
CRVAL1CRVAL2CRPIX1
CRPIX2
CDELT1CDELT2CTYPE1CTYPE2=0.00 / arcsec=
0.00 / arcsec=
257.00 /=257.00 /=4.91106 / arcsec=
4.91106 / arcsec= ’solar-west’/= ’solar-north’/35

(4) Parameters for each synthesis program• example for Hanaoka
PROGNAME= ’snap2d17 v5.1 Y. Hanaoka’ /
BUNIT
= ’K
’
/ disk = 10000 K
SOLR-FAC=
1.01250 / radius correction factor
NFRCAL =1 / number of calibration frames
CRINPUT =-0.50 / clean criterion input
MBEAMC = ’yes’
/ main beam correction
DISKRSTR= ’yes’
/ disk restoration
DDOFF1 =-12.77 / x-offset of the dirty disk
DDOFF2 =10.68 / y-offset of the dirty disk
DDCORR =0.9631 / correlation between dirty disk and model
DSKBR=
37145.51 / brightness of the dirty disk
CRITER =24384.39 / clean criterion
NCOMPO =1050 / number of clean components• example for Koshix
PROGNAME= ’snap2d51_koshix_vfast’ /FRAME=
16501 /ICAL=
3 / integration for calibration
ITGR=
3 / integration for restoration
ICLN=
3 / integration after restoration
BUNIT
= ’k
’
/ disk = 10000 K
CRITER =3000.0 / CLEAN criterion
SOLR-FAC=
1.01250 / radius correction factor
GAINP=
0.020 / CLEAN loop gain for estimation of sky and disk
GAINE=
0.200 / CLEAN loop gain
TRIM=
0.800 / CLEAN trim level
NCOMPO =66143 / number of CLEAN components
DDOFF1 =0.5 / x-offset of the dirty disk
DDOFF2 =0.9 / y-offset of the dirty disk
NCLNYN = ’yes’
/ negative CLEAN
JCIMYN =1 / jitter - add/sub - integration
PJIMYN =1 / projection - integration
MBEAMC = ’yes’
/ main beam correction

B.3

Implimentation to subroutines

Subroutines are given in soft/helioglib in order to write the above header to NoRH FITS ﬁles.
1. For Needed part, use subroutine puthdr.
2. For Ephemeris part, use subroutine putoep.
3. For Coordinate part, use subroutine putcor.
4. For parameters of each synthesis program, make an adequate subroutine for its own.

36

C

NoRH data archive: anonymous FTP

The Astronomy Data Center of NAOJ has prepared the anonymous FTP server for the NoRH dataarchive. The URL is
ftp://solar-pub.nao.ac.jp/pub/nsro/norhDAcknowledgement

We thank the following people. SolarSoftware is a software package for analysis of Solar Data on IDL.
That is supported under various NASA contracts (SXT/EIT/MDI/TRACE/YPOP etc.) and is all in the
public domain. Yohkoh is an international project for solar observation by ISAS in Japan, NASA in the U.
S. and SERC in the U. K. GOES data are supplied courtesy of NOAA/NGDC from www.ngdc.noaa.gov.
The utility program C2FITS is developed by Dr. T. Bastian at NRAO and is improved by Dr. S.
White (U. Maryland). The JavaScript program in our NoRH Web site is developed by Dr. D. Zarro at
NASA/GSFC. IDL is a product by Research System Inc. We also thank Dr. S. Pohjolainen from HUT,
Metsahovi Radio Observatory for reading and checking the manual.

References
Dulk, G. A., 1985, ARAA, 23, 169
Hanaoka, Y., et al., 1994, Proc. of Kofu Symp., 35
Nakajima, H., et al., 1994, Proc. of the IEEE, 82, 705
Nishio, M., et al., 1994, Proc. of Kofu Symp., 19 Ramaty, 1969, ApJ, 158, 753

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