Observation interruptions and instrumental problems of NoRP since 2020

Shimojo and Iwai (2023) presented the history of the Nobeyama Radio Polarimeters (NoRP) until about 2020. The NoRP operations have continued after 2020, and the observations are sometimes suspended due to various problems. This page shows suspensions and instrumental problems with long term (>1 week) since 2020 for users of NoRP data.



Update: 2024/01/17
Date
StartEndObs. Freq.Descriptions of troublesAnnouncement Date
2023/10/172023/12/123.75 GHz Due to problems with the declination axis encoder, observation was sometimes interrupted.New
17 Jan 2024
2023/02/102023/04/101 GHz Due to the trouble with the mortor's axis of the declination axis, the observation was suspended.May 2023
2022/12/142023/01/121 GHz Due to the trouble with the encorder's axis of the right ascension axis, the observation was suspended. May 2023
2022/11/172023/02/0135 GHz The outputs in the morning (until 11:00JST) were unstable and anomalous. It was caused by the deteriorated power supply for the local ocsillator.May 2023
2022/02/242022/04/053.75 GHz Due to the trouble with the motor of the declination axis, the observation was suspended. May 2023
2021/06/112021/11/071 GHz As mentioned in Shimojo and Iwai (2023), the local oscillator of 1 GHz had a glitch between September 2020 and November 8, 2021. To validate the 2GHz absolute flux calibration (see below), we make the ratio plots between the 1, 2, and 3.75GHz. From the plots, we clearly see that the glitch worsened after the planned power outage on June 11, 2021, and found that the gain varied from the scheduled power outage to November 8, 2021. To calibrate the variation, we applied the correction factor "0.93" to 1 GHz data in several materials (daily flux [txt, CSV files], FITS database, etc.)25 Sep. 2023
2021/06/072021/06/2817 GHz During the observation, the output becomes the level of AMB and not be back to the level of the Sun. It was caused by the disconnection of the control line for polarization change.May 2023
2021/02/222021/03/192 GHz Due to the trouble with the control of the right ascension axis, the observation was suspended.May 2023
2020/11/Mid2020/12/101 GHz The solar flux was decreasing in the afternoon. It was caused by the shadow of a tree, and we cut down the tree.May 2023
2020/10/082020/11/122 GHz Due to the trouble with the pointing sensor of the declination axis, the observation was suspended.May 2023
2019/11/292020/07/031 GHz Due to the trouble with the pointing sensor of the declination axis, the observation was suspended.May 2023
2019/10/292020/09/049.4 GHz The outputs around noon (JST) became zero. It was caused by the trouble in the IF cable between the antenna to the buliding.May 2023
2019/05/152 GHz To avoid interference from the base stations of cell phones, we changed the FE system of 2GHz from the DSB to the SSB system. After the change, the solar fluxes obtained from NoRP data are overestimated. We performed the 2GHz solar observations using the standard horn antenna in July 2023 to calibrate the absolute fluxes. Finally, we obtained the correction factor "0.94". We applied the factor to the daily flux table [txt, CSV files], IDL procedures of reading raw data, FITS file database, and solar cycle plot. The calibration project was carried out with the essential contributions of Watanabe Lab., National Defence Academy of Japan.25 Sep. 2023
2018/11/252021/10/1635/80 GHz Due to the trouble with the gears of the declination axis, the observation was suspended. May 2023

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