Overview:
To maintain the maximum possible amount of 45-m telescope observing time, approximately 3,000 hours per year, with the current resources available at Nobeyama Radio Observatory, we are seeking individuals who can contribute to CSV observations of the 45-m telescope (“CSV contributors”). This is also a good opportunity for beginners to learn antenna operation and the principles of telescope performance measurements, and applications from those without prior experience are also welcome.
- What is CSV? CSV stands for Commissioning and Science Verification. Before the observing season begins, CSV is conducted to verify whether there have been any changes, mainly degradation, in the performance of the antenna and receivers, in order to ensure the accuracy of scientific observations during that season.
- Normally, the performance of instruments is measured using dedicated measurement equipment. In such cases, however, the measurement accuracy is generally limited by the accuracy of the measurement equipment and the measurement system itself. It is difficult to evaluate the overall performance of highly precise instruments such as large antennas and high-sensitivity receivers, using measurement equipment alone, at the level of accuracy required for scientific observations.
- In CSV, the performance of the instruments is evaluated by observing reference astronomical sources instead of using measurement equipment. For this reason, it is sometimes referred to as CSV observations.
Programme:
- Background：
- As of July 2026, Nobeyama Radio Observatory has two research and education staff members and four technical staff members, and further staff reductions are expected in the future due to mandatory retirements.
- In recent years, the 45-m telescope has been made available from September in order to maximize the amount of science observing time during the winter season and to provide sufficient development time for instrumentation developers. As a result, the summer maintenance period has become shorter than it was during the previous shared-use era. Since summer maintenance during the daytime and CSV observations at night are carried out in parallel, the workload on observatory staff has increased.
- System：
- We are seeking individuals who can contribute to observatory CSV activities (“CSV contributors”).
- CSV contributors will also conduct scientific observations.
- For each night of contribution, 4 hours of science observing time will be allocated. For details, please refer to the “Allocation” section below.
- This year, applications are limited to users based in Japan.
- CSV observation frame works：
- The observing time is scheduled to be from 18:00 to around 02:00 the following day.
- The observing period is from August 21 to October 31.
- For details, please refer to the 45-m schedule, specifically the sections marked “NRO CSV.”
- How to read the schedule: the horizontal axis shows LST (Local Sidereal Time). LST shifts relative to JST by 4 minutes per day. JST dates are shown on both the left and right sides, but please note that the dates are different. The diagonal lines indicate JST times: the orange line corresponds to JST = 0h, i.e., the date change line, and the black lines correspond to JST = 6h, 12h, and 18h.
- CSV contributors may participate remotely.
- CSV observations will be conducted by a pair consisting of either an NRO staff member on site or an experienced CSV contributor, together with another CSV contributor.
- CSV contributors will be responsible for telescope operation and safety management.
- Menu of observations：
- There are mainly two types of measurements: squint measurements and efficiency measurements.
- Squint measurements:
- These measurements determine the pointing of each receiver, such as FOREST and Z45, and correct the instrumental offset parameters if any offsets are found. For the 45-m telescope, the pointing is first adjusted using the H40 receiver. In squint measurements, the pointing accuracy of each receiver is evaluated by measuring the pointing offset between H40 and the other receivers. In general, these values do not change from the previous year unless the beam transmission system or receivers have physically moved.
- Efficiency measurements:
- These measurements determine the antenna efficiency for each receiver, including the aperture efficiency and main-beam efficiency. The aperture efficiency represents the sensitivity to point sources, while the main-beam efficiency represents the sensitivity to sources extended on the scale of the main beam. These are important parameters used to convert the antenna temperature obtained from observations into brightness temperature. They are evaluated by observing astronomical sources with known brightness distributions, mainly continuum emission from planets. For the 45-m telescope, on-site work is required for the observing setup, but this will be handled by NRO staff. Values similar to those from the previous year are expected, unless the surface accuracy of the main reflector panels has degraded, the beam transmission system has shifted, or the receiver performance has deteriorated.
- Caveats：
- CSV observations are conducted as part of the contributor’s own scientific observations. Nobeyama Radio Observatory will not provide honoraria, travel expenses, or other financial support. Please also note that labor management, including management of working hours and nighttime work, as well as safety management, including ensuring safe travel home after nighttime work, must be handled in accordance with the regulations of the contributor’s own institution. Nobeyama Radio Observatory assumes no responsibility for these matters.
- Students should consult with their academic supervisors before applying. The supervisor is not required to be present during CSV observations or to provide prior training.
- No scientific review will be conducted for the proposed scientific observations.
- On the time allocation：
- This year, applications are being accepted for 32 nights.
- If the number of applications exceeds the available nights, the observing time will be allocated after an equal reduction among applicants. If there is a minimum amount of time required to achieve your scientific observations, please indicate the minimum number of nights requested in the application form. If we are unable to allocate at least the minimum number of nights requested, your application will be canceled.
- If you are also applying for the Regular Program (paid observing time) and wish to reduce your Regular Program observing time by the amount of time obtained through CSV contributions, please indicate this in the application form for the CSV Observing Contribution Program. This applies if you wish to keep the total amount of observing time from the Regular Program and CSV contributions constant.
- Please note that the allocation of scientific observing time under the Regular Program will be given priority, and the allocation of observing time obtained through CSV contributions will be treated as secondary priority.
- How to apply：
- Contact: Please contact the Help Desk. Inquiries in Japanese are welcome. You may also contact us via the Nobeyama45 Discord.
After the application:
- The allocation will be carried out by the observatory.
- The allocation results will be sent to the PI by email within approximately one to two weeks.
- A remote connection test will be conducted in late August. Please participate in this test.
- If you will travel to Nobeyama to conduct observations on site, please submit a visit plan from here.