Skip to main content
End of Swift Science Operations, CHIME Notices Unavailable During Upgrade. See news and announcements

GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32763 results found.

  1. EP240618a: TRT optical upper limit
  2. Fermi GRB 240619A: Global MASTER-Net observations report
  3. EP240617a: STEP/T80S optical limits
  4. GRB 240615A: possible transient detection from Wendelstein observations
  5. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  6. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  7. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  8. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  9. GRB240615A: 1.3m DFOT optical upper limit
  10. EP240617a is likely a GRB event
  11. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  12. GRB 240615A: J-band upper limits from WINTER
  13. GRB 240615A: Fermi GBM Observation
  14. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  15. GRB 240615A: GECAM detection
  16. X-ray transient EP240414a: Chandra late time observation
  17. GRB 240615A: FLWO-1.2m optical upper limits
  18. Fermi GRB 240616A: Global MASTER-Net observations report
  19. Konus-Wind detection of GRB 240615A (short/hard)
  20. GRB 240615A: GOTO optical upper limits
  21. GRB 240615A: Swift ToO observations
  22. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  23. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  24. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  25. GRB 240603A: VZLUSAT-2 detection
  26. GRB 240612A: GRBAlpha detection
  27. Fermi GRB 240612B: Global MASTER-Net observations report
  28. Fermi GRB 240612A: Global MASTER-Net observations report
  29. GRB 240607A: GECAM detection of a bright long burst
  30. Fermi GRB 240611A: Global MASTER-Net observations report
  31. Konus-Wind detection of GRB 240607A
  32. EXO 0748-676: Swift-BAT refined analysis
  33. GRB 240529A: LBT optical detection and late temporal decay
  34. GRB 240529A : MITSuME Akeno optical afterglow detection
  35. Fermi GRB 240610A: Global MASTER-Net observations report
  36. IPN triangulation of GRB 240607A
  37. Fermi GRB 240608A: Global MASTER-Net observations report
  38. Konus-Wind detection of GRB 240606B
  39. Fermi GRB 240607A: Global MASTER-Net observations report
  40. GRB 240529A: NOEMA detection
  41. GRB 240607A: Fermi GBM Observation
  42. GRB 240606B: Fermi GBM Observation
  43. Swift Trigger 1235109: consistent with noise and not astrophysical
  44. GRB 240607A: AstroSat CZTI detection of bright long burst
  45. GRB 240607A: Fermi GBM detection of a very bright burst
  46. GRB 240529A: radio detection with AMI-LA
  47. GRB 240606B: GECAM-B detection a long burst
  48. GRB 240606B: Swift ToO observations
  49. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  50. Konus-Wind detection of GRB 240603A
  51. Fermi GRB 240604A: Global MASTER-Net observations report
  52. IPN triangulation of GRB 240531A (short)
  53. Fermi GRB 240605A: Global MASTER-Net observations report
  54. Fermi GRB 240605C: Global MASTER-Net observations report
  55. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  56. IPN triangulation of GRB 240603A
  57. GRB 240529A: SAO RAS optical observations
  58. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  59. Fermi GRB 240603C: Global MASTER-Net observations report
  60. Swift Trigger 1232465: consistent with noise
  61. GRB 240529A: MASTER prompt OT detection
  62. GRB 240529A: continued SAO RAS optical observations
  63. Fermi GRB 240602A: Global MASTER-Net observations report
  64. GRB 240529A: further SAO RAS optical observations
  65. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  66. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  67. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  68. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  69. LXT 240528A: GSP optical upper limit
  70. GRB 240529A: 1.3m DFOT Optical observations
  71. LIGO/Virgo/KAGRA S240527en: Updated Sky localization
  72. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  73. GRB 240529A : Mondy optical observations
  74. Konus-Wind detection of GRB 240529A
  75. IPN triangulation of the initial episode of GRB 240529A
  76. GRB 240529A: SAO RAS optical observations
  77. LIGO/Virgo/KAGRA S240531bp: Updated Sky localization
  78. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  79. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  80. GRB 240529A: Insight-HXMT/HE detection
  81. GRB 240529A: optical photometry from Konkoly
  82. GRB 240529A: GROWTH-India optical follow-up
  83. GRB 240529A: T193/MISTRAL observations
  84. GRB 240529A: Redshift from GTC/OSIRIS+
  85. GRB 240529A: AKO Optical Afterglow Detection
  86. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  87. GRB 240529A: J-band detections with WINTER
  88. GRB 240529A: Skynet Optical Observations
  89. GRB 240529A: Swift-BAT refined analysis
  90. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  91. GRB 240529A: Swift/UVOT Detection
  92. GRB 240529A: NOT optical observations
  93. GRB 240529A: AstroSat CZTI detection
  94. GRB 240529A: GOTO optical afterglow detection
  95. LIGO/Virgo/KAGRA S240527fv: Updated Sky localization
  96. GRB 240527B: Fermi GBM Observation
  97. Fermi GRB 240527A: Global MASTER-Net observations report
  98. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  99. GRB 240527B: Fermi-LAT detection
  100. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Questions or comments?
Contact GCN directly.
Have you found a bug in GCN?
Open an issue.
Want to contribute code to GCN?
Get involved on GitHub.

gcn.nasa.gov

A service of the Astrophysics Science Division at NASA Goddard Space Flight Center

Looking for U.S. government information and services? Visit USA.gov