CTA-LST1 daily check, problem list

Date

Description of the problem

Images

Resolution

Date

Description of the problem

Images

Resolution

2024-05-10

Run1736

2024-05010

Run17387,

MAGIC lidar event.

High intensity laser beams are emmitted priodically. Its scatterd light is detected by LST.

 

image-20240823-003358.png

 

image-20240823-004846.png

 

report as “lidar-like events”. These runs are categolize “low quality runs” instead of “anomaly runs”.

2024-05-17

Run17131

A bright light illuminate camera.

report as “car-flash like events” in the category of “low quality runs”.

 

2024-06-10

Run17740, 17741

Bright light continuously iluminate telescope. The bright light is sometime come from the domitory, and sometime caused in the air as a airglow.

 

 

 

report as “bright light” in the category of “low quality runs”.

2024-05-06

Run1733

All event is tagged into three categories: Flat Field (FF), Pedestal, cosmic. However, this tagging can sometimes fail. It suddenly malfunctions during observation. It seems to occur when there are bright events like LIDAR or car flash.

 

 

Notice it to exparts and report as “wrog enent tagging in the category of “anomaly runs”.

2024-05-14

Run17409

Calibration run

 

 

Exclude from the daily check report.

2024-07-07

star trails forms circle on the camera, when the telescope looking near the zenith.

 

 

this is nomarl. no need to report.

2024-06-23

Run 17779

staraight-line image of star trails.

 

 

if observation is drift scan, this is nomal. if not , telescope may lost target position. report it to experts.

2024-05-05

run 17310

if tracking fails or the telescope loses the target, the star tracking may become erratic.

 

 

Sould be brought to the attention of experts.

2024-06-12

When Pedecal run encounters a trouble, all DL1 files of that night are affected.

 

 

 

This should be written in the report.

2024-06-13

Run17778

 

Wrong setting caused by stereo trigger test.

 

 

explain it in the comment.

2024-08-26

Run18676-18691

FF charge values are about 60 pe in all RUNs which is lower than that in the past. In particular, the last two RUNs are even lower.

FF rel. time values for many pixels are high in all RUNs.

 

 

explain it in the comment.

 

This is caused by faild calibration, which is performed at begingin of the observation. The reason of this failure is unknown.

2024-08-29

Run18728,18732

The telescope altitude anomaly and the change in the cosmic fraction (>10pe) seem to have occurred at the same time.

 

 

explain it in the comment.

2024-08-26,

every observation

part of FF events are tagged as comsimc. This is constanty happening.

 

nothing to do.

2024-09-02,

RUN18794,18801

RUN18794: tracking failure 7 minutes after start (see attached image) (“we get an error in drive, the drive message logger shows the error: Tracking Failure on both axes for more than 60s” by ELOG).

RUN18801: tracking failure 3 minutes after start (see attached image) (“Structure went to Fault. Acknowledge the error, sync, and we are fine to go.” by ELOG).

 

 

explain it in the comment.

2024-09-02,

RUN18790-18810

FF rel. time values are high for many pixels in the lower left in all RUNs.

 

 

explain it in the comment.

2024-09-09,

RUN18965,18966

FF rel. time values are high for cluster(6,6) by -9 ns.

 

 

explain it in the comment.

2024-09-10,

RUN18996

tracking failure 20 minutes after start (“we see a wobble change has happened at around 23:16 but it does not show up in the schedule also no new run seems to have started.” by ELOG).

 

 

explain it in the comment.

2024-08-01,

RUN18392,18393,18394

no interleaved flat field data ("AMC in fault, Calibox is in ERROR." by ELOG).

 

 

explain it in the comment.

2024-08-02,

RUN18402

no interleaved flat field data from the middle of a run (the same error as yesterday, group 5, 6 and 8 of the AMC are disconnected and the calibox is in error" by ELOG). The pixel distributions of interleaved pedestal mean charge and cosmic rate had line patterns.

 

 

explain it in the comment.

2024-10-28, 29, 30

The camera window fogged up because the internal temperature of the camera dropped below the dew point.

 

 

The data should be categolized as low quolity. It should be specifically noted in the daily check report, like “The camera window fogged up might have been caused by the internal temperature of the camera dropping below the dew point.”

If no action was taken, it should be brought to the attention of the operations team.

2024-12-04

The Az drive stopped during observation. Even though the drive was anomalous, the operation continued without it being noticed.

 

 

 

Should be noticed in the report and brought to the attention of the drive team.