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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

24 results found.

  1. LIGO/Virgo/KAGRA S230518h: Upper limits from a two-week IceCube neutrino search
  2. LIGO/Virgo/KAGRA S230518h: Updated Sky localization
  3. LIGO/Virgo/KAGRA S230518h: Upper limits from Glowbug gamma-ray observations
  4. LIGO/Virgo/KAGRA S230518h: TESS observations of the localization region
  5. LIGO/Virgo/KAGRA S230518h: No transient candidates in CALET observations
  6. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for MeerLICHT candidates: AT2023ixg and AT2023iyb
  7. IPN triangulation of GRB 230518A (short)
  8. LIGO/Virgo/KAGRA S230518h: ATCA follow-up of candidate counterparts
  9. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  10. LIGO/Virgo/KAGRA S230518h: Swift/UVOT Upper Limits for Swope candidates: SSS23a, SSS23b and SSS23c
  11. LIGO/Virgo/KAGRA S230518h: ATLAS observations of the skymap
  12. LIGO/Virgo/KAGRA S230518h: Swope Search and Candidate Counterpart Identification
  13. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  14. LIGO/Virgo S230518h: AGILE/MCAL observations
  15. LIGO/Virgo S230518h: Swift XRT observations, 8 X-ray sources
  16. LIGO/Virgo/KAGRA S230518h: Coverage and upper limits from MAXI/GSC observations
  17. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  18. LIGO/Virgo/KAGRA S230518h: AstroSat CZTI non-detection and upper limits
  19. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  20. LIGO/Virgo S230518h: Global MASTER-Net observations report
  21. LIGO/Virgo/KAGRA S230518h: Updated Sky localization and EM Bright Classification
  22. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  23. LIGO/Virgo S230518h: Upper limits from IceCube neutrino search
  24. LIGO/Virgo/KAGRA S230518h: Identification of a GW compact binary merger candidate
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