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"

7407 results found.

  1. GRB 111211A: NOT afterglow confirmation
  2. GRB 111211A: Swift/XRT target of opportunity observation
  3. GRB 111211A: GROND afterglow candidate
  4. GRB 111210A: GROND observations
  5. GRB 111210A: SDSS prior imaging
  6. GRB 111210A: Gemini-North candidate counterpart
  7. GRB 111210A: Swift detection of a burst
  8. GRB 111209A: TAROT La Silla observatory optical detection
  9. GRB 111209A: Swift detection of a long burst with an optical counterpart
  10. GRB 111204A: Swift detection of a burst
  11. GRB 111129A: Swift detection of a burst with an optical counterpart
  12. GRB 111123A - NOT optical observations
  13. GRB 111123A: TNG NIR detection of the afterglow candidate
  14. GRB 111123A: Swift detection of a burst
  15. GRB 111117A: Chandra detection of the afterglow
  16. GRB 111121A: Swift detection of a short hard burst
  17. GRB 111117A: Gemini Afterglow Limits
  18. GRB 111117A: GROND observations
  19. GRB 111117A: Swift detection of a short hard burst
  20. GRB 111107A: GROND observations
  21. GRB 111107A: Swift detection of a burst with an optical counterpart
  22. Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
  23. GRB 111103B: Swift detection of a strong burst from a GRB or Galactic source
  24. GRB 111029A: Swift detection of a burst
  25. GRB 111022B: 10.4m GTC z'-band observations
  26. GRB 111022A: RIzY Observation
  27. GRB 111022A: Preliminary UVOT TDRSS Non-Detection
  28. GRB 111022B: Swift detection of a burst
  29. GRB 111020A: Swift detection of a short burst
  30. GRB 111018A: Swift detection of a burst
  31. GRB 111016A: Gemini Detection of the NIR Counterpart
  32. GRB 111016A: P60 Afterglow Candidate
  33. GRB 111016A: Swift detection of a burst
  34. EVLA 22 GHz Detection of GRB 111008A
  35. GRB 111008A: Gemini spectroscopic redshift
  36. GRB 111008A: Swift detection of a burst
  37. GRB 110928A: Swift/UVOT finding chart observation
  38. GRB 110924A: Swift detection of a possible burst
  39. GRB 110918A: submm observations from APEX
  40. GRB 110921A: optical observations in Mt. Terskol and Maidanak observatories
  41. GRB 110921A: MITSuME Akeno Optical Observation
  42. GRB 110921A : TNT optical counterpart candidate
  43. GRB 110921A: Swift detection of a burst
  44. GRB 110918A: Gemini-N redshift
  45. GRB 110918A: Afterglow Confirmation from PTF
  46. GRB 110918A: GROND detection of the afterglow candidate
  47. GRB 110918A: INT optical detection of Swift candidate afterglow
  48. Swift detection of short bursts from PSR J1647-4552
  49. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  50. GRB 110915B: Afterglow candidate from OSN
  51. GRB 110915B: XRT afterglow candidate
  52. GRB 110915A: Swift detection of a burst
  53. GRB 110905A: Potential BAT trigger on MAXI J1836-194
  54. GRB 110825A: GMG optical observation
  55. GRB 110825A: optical afterglow candidate
  56. Swift-BAT Trigger 501485 is noise
  57. GRB 110820A: Swift/UVOT Upper Limits
  58. GRB 110820A: Position udpate + 2nd epoch data
  59. GRB 110820A: Swift detection of a burst
  60. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  61. GRB 110818A: Swift detection of a burst
  62. SGR J1834.9-0846: A Neutron Star in W41?
  63. GRB 110808A: VLT/X-shooter spectroscopy
  64. GRB 110808A: Swift detection of a burst with optical counterpart
  65. GRB 110807A: Swift detection of a burst or a posible new SGR
  66. GRB 110801A: Swift detection of a burst with an optical counterpart
  67. GRB 110731A: FTN+FTS afterglow observations
  68. GRB 110731A: Swift detection of a burst with an optical counterpart
  69. GRB 110721A: Swift observations of afterglow candidate
  70. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  71. GRB 110726A: Swift/UVOT Detection
  72. GRB 110726A: Liverpool Telescope observations
  73. GRB 110726A: Swift detection of a burst
  74. IPN triangulation of GRB 110721A
  75. GRB 110721A: Gemini-South spectroscopy of the potential optical counterpart
  76. GRB 110721A: potential counterpart candidate
  77. GRB 110719A: Swift detection of a burst
  78. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  79. Swift J1822.3-1606
  80. GRB 110715A: Swift detection of a bright burst with an optical counterpart
  81. Swift trigger 457076 is not a GRB
  82. Swift Trigger 457076: a possible GRB
  83. GRB 110709B: GROND Detection of an Afterglow Candidate
  84. GRB 110709B: Swift detection of a burst
  85. GRB 110709A: Swift detection of a burst
  86. GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst
  87. Swift-BAT trigger 456532 is not astrophysical
  88. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  89. GRB 110625A: Swift detection of a burst
  90. Swift J185003.2-005627: Swift detection of a burst from a new Galactic transient
  91. GRB 110618A: SMARTS optical observations
  92. GRB 110604A: final update on Swift-XRT observations
  93. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  94. GRB 110530A: Swift detection of a burst with an optical afterglow
  95. GRB 110521A: Swift detection of a burst
  96. GRB 110520A: Swift detection of a burst
  97. GRB 110503A: TAROT Calern observatory optical observations
  98. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  99. GRB 110422A: Swift detection of a burst
  100. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate

Advanced

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