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"

19551 results found.

  1. GRB 100823A: Enhanced Swift-XRT position
  2. GRB 100823A: Swift detection of a burst
  3. EVLA radio afterglow detection of GRB 100814A
  4. GRB 100814A: optical observations
  5. GRB100816A: MITSuME optical upper limits
  6. GRB 100814A: NOT optical observations
  7. GRB 100816A: NOT optical observations
  8. GRB 100814A : Lulin optical observation
  9. GRB 100816A : Lulin r'-band observation
  10. GRB 100816A: Swift UVOT Observations
  11. GRB 100816A: 1.23m CAHA optical observations
  12. GRB 100816A: Enhanced Swift-XRT position
  13. GRB 100816A: Gemini-N imaging
  14. GRB 100816A: CQUEAN riz-band Detection, Host Galaxy?
  15. GRB 100816A: TAROT Calern observatory optical detection
  16. GRB 100816A: MASTER Optical Limits
  17. GRB100816A: TNG optical afterglow confirmation.
  18. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  19. GRB 100814A: Submm observations from APEX
  20. Swift/UVOT observations of GRB100814A
  21. GRB 100814A: Enhanced Swift-XRT position
  22. GRB 100814A: GROND Detection of the Optical/NIR Afterglow
  23. GRB 100814A: Swift detection of a burst with an optical afterglow
  24. Swift-BAT trigger 431582 likely is IGR J17464-2811
  25. GRB 100805A: the 4-th epoch of SAO RAS optical observations
  26. GRB 100805A: optical observation in CrAO (correction to the GCN 11077 and second epoch)
  27. GRB 100802A: further NOT observation
  28. GRB 100807A: P200 Infrared Observations
  29. GRB 100805A: the 3-rd epoch of SAO RAS optical observations
  30. GRB100807A: optical observation in CrAO
  31. GRB 100805A: optical observation in CrAO
  32. GRB 100805A: 2-nd epoch of SAO RAS optical observations
  33. GRB100807A: MITSuME optical upper limits
  34. GRB 100807A: P60 Optical Afterglow Discovery
  35. GRB 100807A: Swift/UVOT Upper Limits
  36. GRB 100805A: SAO RAS optical observations
  37. GRB 100807A: Enhanced Swift-XRT position
  38. GRB 100807A: Swift detection of a burst
  39. GRB 100805A: IAC80 and 1.5m OSN optical observations
  40. GRB 100805A: Early RAPTOR Observations
  41. GRB 100805A: Swift/UVOT Observations of the Optical Afterglow
  42. GRB 100802A: WIYN observations
  43. GRB 100805A: IAC80 BVR-band observations
  44. GRB 100805A: Swift-XRT Refined Analysis
  45. GRB 100805A: GRAS 002 optical observations
  46. Trigger 430975: Swift detection of a possible burst
  47. GRB 100805A: I-band detection from 1.23m CAHA telescope.
  48. GRB 100805A: Enhanced Swift-XRT position
  49. GRB 100805A: Further P60 Monitoring
  50. GRB 100805A: P60 Optical Afterglow Candidate
  51. GRB 100805A: Swift detection of a burst with an optical counterpart
  52. GRB 100728B: optical photometry of ISON-NM
  53. GRB 100713A: second epoch Maidanak optical observation
  54. GRB 100713A: CrAO optical limits
  55. GRB 100802A: NOT optical observation
  56. GRB100802A: MITSuME optical upper limits
  57. GRB 100802A: P60 Observations
  58. GRB 100802A: Swift/UVOT Possible Optical Afterglow
  59. GRB 100802A: Enhanced Swift-XRT position
  60. GRB 100802A: Swift detection of a burst
  61. GRB 100728B - NOT optical observation
  62. GRB 100728B: Swift/UVOT Observations
  63. GRB 100728B: Continued KAIT observations
  64. GRB 100728B, Swift-BAT refined analysis
  65. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  66. GRB 100727A: Swift/UVOT Upper Limits
  67. GRB 100728B: Enhanced Swift-XRT position
  68. GRB 100728A: Swift/UVOT Upper Limits
  69. GRB 100728B: Fermi GBM observation
  70. GRB 100728B: GROND Detection of the NIR Afterglow
  71. GRB 100728B: optical detection
  72. GRB 100728B: Swift detection of a burst with an optical counterpart
  73. GRB 100728A: Skynet/PROMPT Detections
  74. GRB 100728A: Fermi GBM observation
  75. GRB 100728A: Enhanced Swift-XRT position
  76. GRB 100728A: Swift detection of a burst
  77. GRB 100727A: Fermi GBM observation
  78. GRB 100727A: Enhanced Swift-XRT position
  79. GRB 100727A: Swift detection of a burst
  80. GRB100725B: MITSuME optical upper limits
  81. GRB 100725B: refined XRT analysis
  82. GRB 100725A: GROND upper limits
  83. GRB 100725B: Swift/UVOT Upper Limits
  84. GRB 100725A: Swift/UVOT Upper Limits
  85. GRB 100725B: Enhanced Swift-XRT position
  86. GRB 100725A: Enhanced Swift-XRT position
  87. GRB 100725B: Swift detection of a burst
  88. GRB 100725A: Swift detection of a burst
  89. GRB 100724B: Fermi GBM detection
  90. GRB 100724A: Enhanced Swift-XRT position
  91. GRB 100724A: Swift/UVOT observations
  92. GRB 100724A: Swift detection of a burst
  93. GRB 100614A: 10.4-m GTC deep-optical limit
  94. GRB 100722A: Fermi GBM detection
  95. GRB 100718A: MASTER-Net optical prompt and alert observations
  96. GRB 100713A: optical observation in Maidanak
  97. GRB 100713A: Swift XRT refined analysis
  98. GRB 100713A: GROND upper limits
  99. GRB 100713A: TNG optical observations
  100. GRB100713A: Swift X-ray afterglow detection

Advanced

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