Skip to main content
JSON Notices via Email, Kafka Cron Jobs, Submitter Profile, GCN is Hiring. 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"

19662 results found.

  1. GRB240730A: BOOTES-5/JGT early optical upper limit
  2. Swift GRB 240730A: Global MASTER-Net observations report
  3. GRB 240730A: Swift-XRT refined Analysis
  4. GRB 240715A: Swift-XRT afterglow detection
  5. GRB 240730A: KAIT Optical Upper Limit
  6. GRB 240730A: Swift/UVOT Upper Limits
  7. GRB 240730A: Enhanced Swift-XRT position
  8. GRB 240730A: Swift detection of a burst
  9. GRB 240727A: Swift-BAT refined analysis
  10. LIGO/Virgo/KAGRA S240615dg: GRAWITA wide-field optical observations
  11. GRB 240727A: observations of optical counterpart.
  12. GRB 240727B: Swift-XRT observations
  13. GRB 240727A: Swift/UVOT detection
  14. GRB 240727A: NOT optical observation
  15. GRB 240727A: JinShan optical upper limits
  16. GRB 240727A Bassano Bresciano Observatory upper limit
  17. GRB 240727A: Swift-XRT refined Analysis
  18. GRB 240727A: Enhanced Swift-XRT position
  19. GRB 240727B: Fermi GBM Observation
  20. Swift GRB240727.16: Global MASTER-Net observations report
  21. GRB 240727B: Swift ToO observations
  22. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  23. GRB240727A: Skynet Optical Afterglow Observations
  24. GRB 240727A: TRT optical afterglow detection
  25. GRB 240727A: KAIT Optical Afterglow Candidate
  26. GRB 240727A: Swift detection of a burst
  27. Swift Trigger 1244778 is not a GRB
  28. Swift GRB240725.11: Global MASTER-Net observations report
  29. GRB 240720A: Swift-BAT refined analysis
  30. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  31. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  32. GRB 240720A: AstroSat CZTI detection
  33. GRB 240720A: Fermi GBM observation
  34. GRB 240720A: Swift detection of a burst
  35. Swift GRB240720.02: Global MASTER-Net observations report
  36. GRB 240718A: Fermi-LAT Detection
  37. GRB 240712A: Swift-BAT refined analysis
  38. GRB 240715A: Swift/UVOT observations of the XRT sources.
  39. GRB 240715A: Swift-XRT observations
  40. GRB240713A: Swift/UVOT Upper LImits
  41. EP240708a: X-ray follow-up observations with Swift/XRT
  42. GRB 240713A: Swift-XRT observations
  43. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  44. GRB 240712A: Swift-XRT refined Analysis
  45. GRB 240715A: Swift ToO observations
  46. GRB 240712A ATCA radio observations
  47. IPN triangulation of GRB 240715A (short)
  48. GW s240422ed: Swift UVOT follow-up
  49. GRB 240712A: Swift/UVOT Upper Limits
  50. The EP-WXT source triggered on July 14th is likely a flaring star
  51. GRB 240713A: Tiled Swift observations
  52. GRB 240712A: Swift detection of a burst
  53. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  54. EP240708a: EP-WXT detection of a fast X-ray transient
  55. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  56. IPN triangulation of GRB 240628B (short)
  57. EP240703a and EP240703b: Swift/XRT upper limits
  58. EP240703c: Kinder optical follow-up and Swift XRT observations
  59. EP240703c: EP-WXT detection of an X-ray transient
  60. IPN triangulation of GRB 240627A
  61. EP240703b: EP-WXT detection of a fast X-ray transient
  62. EP240702a: Swift/XRT upper limit
  63. EP240703a: EP-WXT detection of a fast X-ray transient
  64. EP240702a: EP-WXT detection of a fast X-ray transient
  65. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  66. IPN triangulation of GRB 240619C
  67. GRB 240624A: Swift-BAT refined analysis
  68. Konus-Wind detection of GRB 240619A
  69. GRB240624A: Fermi GBM Observation
  70. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  71. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  72. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  73. Swift GRB 240624A: Global MASTER-Net observations report
  74. GRB 240624A: Swift detection of a burst
  75. GRB 240529A: JinShan optical observations
  76. IPN triangulation of GRB 240615A (short)
  77. EP240618a: Swift/XRT upper limit
  78. EP240617a: tentative Swift/XRT detection of the afterglow
  79. GRB 240619A: Swift-XRT probable afterglow detection
  80. GRB 240619A: Swift ToO observations
  81. GRB 240615A: NOT optical observations
  82. GRB 240615A: possible transient detection from Wendelstein observations
  83. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  84. GRB240615A: 1.3m DFOT optical upper limit
  85. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  86. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  87. GRB 240615A: J-band upper limits from WINTER
  88. GRB 240615A: Fermi GBM Observation
  89. GRB 240615A: Swift-XRT observations
  90. GRB 240615A: GECAM detection
  91. GRB 240615A: FLWO-1.2m optical upper limits
  92. Konus-Wind detection of GRB 240615A (short/hard)
  93. GRB 240615A: GOTO optical upper limits
  94. GRB 240615A: Swift ToO observations
  95. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  96. EXO 0748-676: Swift-BAT refined analysis
  97. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  98. GRB 240529A: LBT optical detection and late temporal decay
  99. GRB 240529A : MITSuME Akeno optical afterglow detection
  100. Trigger 1236151: Swift detection of EXO 0748-676

Advanced

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