GRB241030B

Alert Information

• Name/type of the alert: GRB 241030B
• GCN circular: [1]
• Astro-COLIBRI: [2]
• Triggered by: Swift/XRT
• Alert coordinates:
  • RA: 3 23 10.224 (hh mm ss), Dec: 34 26 48.84 (dd mm ss)
  • RA, Dec in deg (ICRS): 50.793deg, 34.447deg
• Alert arrival time: 2024-10-30 18:37:09 UTC
• Other relevant information:
  • GCN notices + circulars: [3]
  • Redshift (z): z = 2.82 (tentative redshift by OSIRIS@GTC, GCN #38004 [4])

LST Observations

• Dates of data-taking: 2024-10-30
  • 2024-10-30
    • Zenith range (deg): 47 --> 11
    • Transmission9km: tbd
    • Observation condition: dark
    • Observation mode: std wobbles
    • Runs: 19401 - 19411
    • Joint observations with MAGIC? : yes (19401 - 19411)
    • ELOG link:[5]
    • Important comments:

Fast analysis

• Analysis by:
  • Analyzer 1 Tora T. H. Arnesen (IAC - tora.arnesen@iac.es)
  • Analyzer 2

Data-taking information

• Dates of data-taking: 2024-10-30
  • Date (time of observation h) 2024-10-30: h
    • ZD range (deg): 10-49
    • Observations: (see example below)

2024-10-30: [19401 19402 19403 19404 19405 19406 19407 19408 19409 19410 19411]

• Data quality selection: all runs survived good quality selection (max NSB std: 2.3)

General analysis information

• source-independent analysis
• lstchain version: v0.10.12
• DL1b standard production (v0.10/tailcut84), run-wise merged files in:

/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19401.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19402.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19403.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19404.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19405.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19406.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19407.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19408.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19409.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19410.h5
/fefs/aswg/data/real/DL1/20241030/v0.10/tailcut84/dl1_LST-1.Run19411.h5

Monte Carlo information

• All-sky MC production used: 20240131_allsky_v0.10.5_all_dec_base
• Declination line (training): dec_3476

Random forest

Path to the models used:

/fefs/aswg/data/models/AllSky/20240131_allsky_v0.10.5_all_dec_base/dec_3476

DL2 data

The config file to produce the DL2 files must be the one used to produce the RF models. Should be located together with model's files.

Files in:

/fefs/aswg/workspace/tora.arnesen/FOA/GRB241030B/DL2

DL3 data & IRF

Files in:

/fefs/aswg/workspace/tora.arnesen/FOA/GRB241030B/DL3

Configuration used for producing IRF/DL3 files (standard settings):

 "EventSelector": {
   "filters": {
     "intensity": [50, Infinity],
     "width": [0, Infinity],
     "length": [0, Infinity],
     "r": [0, 1],
     "wl": [0.01, 1],
     "leakage_intensity_width_2": [0, 1],
     "event_type": [32, 32]
   }
 },
 "DL3Cuts": {
   "min_event_p_en_bin": 100,
   "min_gh_cut": 0.1,
   "max_gh_cut": 0.98,
   "min_theta_cut": 0.1,
   "max_theta_cut": 0.32,
   "fill_theta_cut": 0.32,
   "allowed_tels": [1]
 },

• 70 % efficiency for both gammaness and theta gamma-ray selection energy-dependent cuts
• Point-like IRF.

High-level analysis and results

Analysis settings

• Gammapy version: 1.2
• 1D analysis (point-like IRF)

Theta2 plot

Settings:

• Theta2 cut for signal extraction: 0.04 deg2
• Normalization range: 0.1 - 0.4 deg2
• Number of off positions: 3
• Energy range: 0.01 - 10 TeV

Daily results

• 2024-10-29: No detection

Error creating thumbnail: File missing

Significance and Excess sky maps

Cross-check

Gammapy version: 1.1

Measured energy axis bounds: 0.2 TeV - 10.0 TeV

True energy axis bounds: 0.1 TeV - 13.0 TeV

Exclusion region radius: 0.35 deg

Error creating thumbnail: File missing

Significance, off significance, and excess maps

Background residuals map