TRAN01 C2

Proposal

Proposal: TRAN01:Spotting the GRB counterpart to gravitational wave detections during the second half of O4
PI: Monica Seglar-Arroyo (mseglar@ifae.es)

Source information

Source: Various. This science case requires multi-coordinate observations. These will be computed by the transient handler using tilepy

Observational settings/limits

Min Zenith [deg] = 0 

Max Zenith [deg] = 70 

Night Sky Background = Both 

Wobbles = Custom 

Instructions for shifters

These alerts are handled by the Transient Handler due to the complexity of the science case. In case you find any problem, please write in the Slack channel #lst1-alert-followup and/or call the Burst Advocate. If you have any specific question or are curious about this science case, dont hesitate to contact the PI.

The filtering criteria that are used by the TH are documented below (as of 24 of April 2024, during the first month of O4b)

• 1. Raven +GRB coincidence case: same proposal as in O4a, i.e. follow always with 10 pointings (3h20' of observation, see TH technical doc for more details). Neutrino case not clear, will clarify in the next weeks.
• 2. BNS (P_BNS>50% and HasRemnant>20% and significant=True in LVK): follow with 10 pointings (3h20' of observation). No skyloc cut for the first one, we will think about skyloc cut if there is more than one.
• 3. BNS impure (P_BNS+P_BHNS>60% or P_BHNS>50% and HasRemnant>50% and significant=True in LVK) : follow with 4 pointings (1h20' of observations). No cut on the skyloc cut for the first one, we will think about skyloc cut if there is more than one.
• 4. Burst (+ significant=True in LVK): Follow with 4 pointings (1h20' of observations). No cut on the skyloc cut for the first one, we will think about skyloc cut if there is more than one (in general, CBC will be there with estimation of parameters, so this type is difficult to have).
• 5. BBH (only follow if LVK alert+excepcional significance, i.e. 1/50 years (CBC)). First alert of this type that it comes, we do 4 pointings for the end-to-end testing (updates, RTA). We will reduce this type to 1 per month max, and 2 pointings for tests. Remove this type of trigger in case the sky grants us with aforementioned cases.

These are the definition of the sky loc criteria:

• loose: 3000deg2
• std: 1000deg2
• tight: 300deg2

case 1 and 2: no skyloc cut, case 3: loose cut, case 4: std and case 5: tight (only LHV).