GRB221221A

Alert Information

• Name/type of the alert: Fermi-GBM Final Position
• GCN notice: [1]
• Triggered by: Fermi-GBM
• Alert coordinates:
  • RA: +05 27 17 (hh mm ss), Dec: +63 23 60 (dd mm ss)
  • RA, Dec in deg (ICRS): 84.94deg, 59.03deg
• Alert arrival time: 2022-12-21T23:01:17UTC
• Other relevant information:
  • Redshift (z):

LST Observations

• Dates of data-taking: 2022-12-21
  • 2022-12-21
    • Zenith range (deg): 34 --> 32
    • Transmission9km: N.A. (MAGIC lidar not working)
    • Observation condition: dark
    • Observation mode: std wobbles
    • Runs: 11551 - 11559
    • Joint observations with MAGIC? : yes
    • ELOG link:[2]
    • Important comments:

Analysis by Irene Burelli (University of Udine - irene.burelli@gmail.com)

Data-taking information

• Overall selected observation time: 161.4 min
• Selected runs: 11551 -> 11559
• Position analyzed: RA 84.94deg, Dec 59.03deg

DL1 data

Used DL1b files produced by LSTOSA

/fefs/aswg/data/real/DL1/20221221/v0.9/tailcut84/

DL2 data

• Random forest:

/fefs/aswg/data/models/20200629_prod5_trans_80/zenith_40deg/south_pointing/20220304_v0.9.3_prod5_trans_80_zen40az180_local_tailcut_8_4

• lstchain v0.9.6 with config file

/fefs/aswg/data/real/DL1/20210809/v0.9/tailcut84/log/lstchain_config_tailcut84_v092.json

Theta2 plot from DL2

• Cuts and parameters used:
  • intensity > 50
  • gammaness > 0.7
  • Theta2_global_cut=0.04
  • leakage < 0.2
  • norm_range_theta2_min=0.4
  • norm_range_theta2_max=0.6

Theta2 plot for GRB221221A.

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