The FITS database of Nobeyama Radio Polarimeters (NoRP)
12 August 2021
Solar Science Observatory,
National Astronomical Observatory of Japan,
National Institute of Natural Sciences
Dear all,
The original raw data of Nobeyama Radio Polarimeters (NoRP1) are stored with thedistinctive format and can be read only using the IDL (Interactive Data Language)
with the SSW (SolarSoftWare). From the point of view of the persistency of NoRP data,
it was not an allowable situation. To change it, we create the FITS files of the NoRP
data and store the files in this FTP/Web site2. A FITS file in the database is constructedfrom the Primary Header Unit (PHU) and binary extension and includes the following
data with 1, 2, 3.75, 9.4, 17, 35, and 80 GHz obtained in a day3.
ü

Stokes-I, and Stokes-V fluxes calibrated automatically (Unit: SFU)ü

Raw data (Stokes-I, Stokes-V)üTime series of the calibration-scans indicators (Sun, Sky, Amb, Zero)üTime series of the attenuation levelüValues for the automatic calibration (Sky, Amb, Zero)üThe daily fluxes with 1, 2, 3.75, and 9.4 GHz calculated manually (in PHU)Except for the daily fluxes, all data are stored on the binary extension. The details ofFITS header of NoRP FITS files are described in the tables at the end of the documents.
The summary plots of the FITS file can be seen on the web page4.
The FITS database includes the NoRP observing data obtained since 1 June 1994. TheFITS files are stored in the “Month” directory under the “Year” directory. The "TFCL"
directory includes the FITS files that the automatic calibrations with all observing
frequencies are failed. Even when the automatic calibration is succeeded, thecalibrated data contains the influences of the interference, weather condition, andNoRP website: https://solar.nro.nao.ac.jp/norp/index.html
ftp://solar-pub.nao.ac.jp/pub/nsro/norp/fits
3
While the start and end times of NoRP observations vary in season, most observation starts
around 22:00UT and ends around 7:00UT. The filename of the FITS files includes the date, but it isthe date of the start time in Japan Standard Time (UTC+9), not in UT.
4 https://solar.nro.nao.ac.jp/norp/html/fits_png_ql/ The plots show the time profile of the calibrated
Stokes-I and Stokes-V fluxes with all observing frequencies in a day.
12

instrument troubles. So, please consider such effects, especially when you obtain thetotal solar flux at non-flare. In higher frequencies (17, 35, 80 GHz), the weather
condition affects strongly. Hence, it is impossible to get the solar fluxes with thefrequencies at a non-flare time. On the other hand, the files in the "TFCL" directory
store the raw data that includes the value at the calibration scans (Sun, Sky, Amb,Zero). Therefore, we might be able to calibrate the data manually.
The daily fluxes with 1, 2, 3.75, and 9.4 GHz stored in the PHU can be used to indicate
the instrument's condition. If the daily flux does not exist in the PHU (or the value is-10000), we recommend not using the data with the observing frequency.
We also provide the Python library5 for reading the NoRP FITS files.
We adopt an open data use policy for scientific and educational purposes. Please besure to acknowledge the use of NoRP data as follows.
in footnote or acknowledgement
lThe Nobeyama Radio Polarimeters (NoRP) are operated by Solar Science
Observatory, a branch of National Astronomical Observatory of Japan, and theirobserving data are verified scientifically by the consortium for NoRP scientificoperations6.

lFacility keywords can be added in the journal articles published by the American
Astronomical Society. The facility keyword for the Nobeyama Radio Polarimetersis "NoRP". For details please see the web site of the American Astronomical
Society: AAS Facility Keywords.

Please enjoy the NoRP data!
Best regards,Masumi Shimojo
as the manager of the NoRP operation since April 201956https://solar.nro.nao.ac.jp/norp/Python/norp_fits.py
The participated institutes in the consortium for NoRP scientific operations.
nAstronomical Observatories, Graduate School of Science, Kyoto University
nDepartment of Science, Ibaraki University
nInstitute for Space-Earth Environmental Research, Nagoya University
nSpace Environment Laboratory, National Institute of Information and communications
technology
nSolar Science Observatory, National Astronomical Observatory of Japan

The details of the NoRP FITS header
Note: The following tables include only specific keywords for NoRP, and the standardkeywords of the FITS format are not included.
The keywords in the Primary Header Unit (PHU)
FREQ1DAILYF01
FREQ2
DAILYF02
FREQ3
DAILYF04
FREQ4
DAILYF09

Indicate the existence of 1 GHz data
1 GHz daily flux calculated manually [SFU]
Indicates the existence of 2 GHz data
2 GHz daily flux calculated manually [SFU]
Indicates the existence of 3.75 GHz data
3.75 GHz daily flux calculated manually [SFU]
Indicates the existence of 9.4 GHz data
9.4 GHz daily flux calculated manually [SFU]

FREQ5

Indicates the existence of 17 GHz data

FREQ6Indicates the existence of 35 GHz data

FREQ7

Indicates the existence of 80 GHz data

The values of the “TTYPEn” keyword in the binary extension
TimeTime from 00:00:00UT, 1 January 1979 [unit: sec]

DVal_xGHz

Indicating the data is valid (1) or not (0)CalI_xGHz

Calibrated Stokes-I flux [unit: SFU]

CalV_xGHz

Calibrated Stokes-V flux [unit: SFU]

RawI_xGhz

Stokes-I Raw data

RawV_xGHz

Stokes-V Raw data

Cal_xGHzTime series of the calibration-scans indicators
0: Sun, 1: Sky, 2: AMB, 4:Zero

ATT_xGHzTime series of the attenuation level

CalD_xGHz

Values for the automatic calibration (Sky, Amb, Zero)SQLD_80GHz

The data obtained Square-Law Detector (80 GHz only)”x” indicates the observing frequency (1, 2, 4 [=3.75], 9 [=9.4], 17, 35, and 80).