Skip to main content
Updates to LVK & CHIME Notices, Schema v7.2.3! See news and announcements

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').
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"

7421 results found.

  1. GRB 120106A: TAROT Calern observatory optical observations
  2. GRB 120106A: Swift detection of a burst
  3. GRB 120102A: Swift detection of a burst with an optical counterpart
  4. GRB 111228A, optical observations
  5. GRB 111229A: GROND afterglow candidate
  6. GRB 111229A: Swift detection of a burst
  7. GRB 111228A, optical observations
  8. GRB 111228A: TAROT Calern observatory. OT seems still bright
  9. GRB 111228A: Swift detection of a burst with an optical counterpart
  10. GRB 111225A: Swift detection of a burst with an optical counterpart
  11. Trigger 510075 is not a GRB
  12. GRB 111211A: optical ovservations at Mt. Terskol observatory
  13. Possible detection of pre-trigger X-ray emission from GRB 111215A by MAXI/GSC
  14. GRB 111215A: Swift detection of a burst
  15. GRB 111211A: NOT afterglow confirmation
  16. GRB 111211A: Swift/XRT target of opportunity observation
  17. GRB 111211A: GROND afterglow candidate
  18. GRB 111210A: GROND observations
  19. GRB 111210A: SDSS prior imaging
  20. GRB 111210A: Gemini-North candidate counterpart
  21. GRB 111210A: Swift detection of a burst
  22. GRB 111209A: TAROT La Silla observatory optical detection
  23. GRB 111209A: Swift detection of a long burst with an optical counterpart
  24. GRB 111204A: Swift detection of a burst
  25. GRB 111129A: Swift detection of a burst with an optical counterpart
  26. GRB 111123A - NOT optical observations
  27. GRB 111123A: TNG NIR detection of the afterglow candidate
  28. GRB 111123A: Swift detection of a burst
  29. GRB 111117A: Chandra detection of the afterglow
  30. GRB 111121A: Swift detection of a short hard burst
  31. GRB 111117A: Gemini Afterglow Limits
  32. GRB 111117A: GROND observations
  33. GRB 111117A: Swift detection of a short hard burst
  34. GRB 111107A: GROND observations
  35. GRB 111107A: Swift detection of a burst with an optical counterpart
  36. Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
  37. GRB 111103B: Swift detection of a strong burst from a GRB or Galactic source
  38. GRB 111029A: Swift detection of a burst
  39. GRB 111022B: 10.4m GTC z'-band observations
  40. GRB 111022A: RIzY Observation
  41. GRB 111022A: Preliminary UVOT TDRSS Non-Detection
  42. GRB 111022B: Swift detection of a burst
  43. GRB 111020A: Swift detection of a short burst
  44. GRB 111018A: Swift detection of a burst
  45. GRB 111016A: Gemini Detection of the NIR Counterpart
  46. GRB 111016A: P60 Afterglow Candidate
  47. GRB 111016A: Swift detection of a burst
  48. EVLA 22 GHz Detection of GRB 111008A
  49. GRB 111008A: Gemini spectroscopic redshift
  50. GRB 111008A: Swift detection of a burst
  51. GRB 110928A: Swift/UVOT finding chart observation
  52. GRB 110924A: Swift detection of a possible burst
  53. GRB 110918A: submm observations from APEX
  54. GRB 110921A: optical observations in Mt. Terskol and Maidanak observatories
  55. GRB 110921A: MITSuME Akeno Optical Observation
  56. GRB 110921A : TNT optical counterpart candidate
  57. GRB 110921A: Swift detection of a burst
  58. GRB 110918A: Gemini-N redshift
  59. GRB 110918A: Afterglow Confirmation from PTF
  60. GRB 110918A: GROND detection of the afterglow candidate
  61. GRB 110918A: INT optical detection of Swift candidate afterglow
  62. Swift detection of short bursts from PSR J1647-4552
  63. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  64. GRB 110915B: Afterglow candidate from OSN
  65. GRB 110915B: XRT afterglow candidate
  66. GRB 110915A: Swift detection of a burst
  67. GRB 110905A: Potential BAT trigger on MAXI J1836-194
  68. GRB 110825A: GMG optical observation
  69. GRB 110825A: optical afterglow candidate
  70. Swift-BAT Trigger 501485 is noise
  71. GRB 110820A: Swift/UVOT Upper Limits
  72. GRB 110820A: Position udpate + 2nd epoch data
  73. GRB 110820A: Swift detection of a burst
  74. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  75. GRB 110818A: Swift detection of a burst
  76. SGR J1834.9-0846: A Neutron Star in W41?
  77. GRB 110808A: VLT/X-shooter spectroscopy
  78. GRB 110808A: Swift detection of a burst with optical counterpart
  79. GRB 110807A: Swift detection of a burst or a posible new SGR
  80. GRB 110801A: Swift detection of a burst with an optical counterpart
  81. GRB 110731A: FTN+FTS afterglow observations
  82. GRB 110731A: Swift detection of a burst with an optical counterpart
  83. GRB 110721A: Swift observations of afterglow candidate
  84. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  85. GRB 110726A: Swift/UVOT Detection
  86. GRB 110726A: Liverpool Telescope observations
  87. GRB 110726A: Swift detection of a burst
  88. IPN triangulation of GRB 110721A
  89. GRB 110721A: Gemini-South spectroscopy of the potential optical counterpart
  90. GRB 110721A: potential counterpart candidate
  91. GRB 110719A: Swift detection of a burst
  92. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  93. Swift J1822.3-1606
  94. GRB 110715A: Swift detection of a bright burst with an optical counterpart
  95. Swift trigger 457076 is not a GRB
  96. Swift Trigger 457076: a possible GRB
  97. GRB 110709B: GROND Detection of an Afterglow Candidate
  98. GRB 110709B: Swift detection of a burst
  99. GRB 110709A: Swift detection of a burst
  100. GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
Looking for U.S. government information and services? Visit USA.gov