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"

36401 results found.

  1. GRB 240809A: Swift detection of a burst with a bright optical counterpart
  2. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  3. EP240807a: STEP/T80S optical limits
  4. GRB 240807B: AstroSat CZTI detection of a short burst
  5. GRB 240801A: GRBAlpha detection
  6. GRB 240807B: Fermi GBM Final Localization
  7. GRB 240710B: VZLUSAT-2 detection
  8. GRB 240805A: ATCA Radio Upper Limits
  9. EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
  10. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  11. EP240802a/GRB240802A: KAIT optical upper limit
  12. GRB 240720B: VZLUSAT-2 detection
  13. GRB 240710A: VZLUSAT-2 detection
  14. GRB 240807A: Fermi GBM Final Localization
  15. GRB 240805B: GIT optical upper limit
  16. EP240806a: KAIT optical observations
  17. GRB 240805B: Swift-BAT refined analysis
  18. GRB 240805A: Swift-BAT refined analysis
  19. EP240804a (GRB 240804B): NOT optical observations
  20. Konus-Wind detection of GRB 240802A (EP240802a)
  21. Improved IPN triangulation of GRB 240802A / EP 240802a
  22. Konus-Wind detection of GRB 240805A
  23. GRB 240805B Bassano Bresciano Observatory upper limit
  24. GRB240805A: Fermi GBM Observation
  25. GRB 240805B: JinShan optical afterglow detection
  26. GRB 240804B/EP240804a: Correction to the GRB name in GCN 37071
  27. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  28. Konus-Wind detection of GRB 240804B (a counterpart of EP240804a)
  29. Fermi Gamma-ray Burst Monitor trigger 240806402/744629911 is not a GRB
  30. GRB 240626B: VZLUSAT-2 detection
  31. GRB 240624B: VZLUSAT-2 detection
  32. GRB 240619C: VZLUSAT-2 detection
  33. EP 240806A: LCO optical observations
  34. GRB 240805B: Optical detection with 1.6m Mephisto
  35. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  36. GRB 240805B: Swift-XRT refined Analysis
  37. GRB 240805B: Swift/UVOT Upper Limits
  38. GRB 240805A: Swift/UVOT Upper Limits
  39. GRB 240805B: BTA optical afterglow candidate
  40. GRB 240805A: SVOM/GRM observation
  41. GRB 240805B: Enhanced Swift-XRT position
  42. GRB 240805B: LCOGT Optical Upper Limits
  43. Swift GRB 240805B: Global MASTER-Net observations report
  44. GRB 240805B: JinShan optical upper limits
  45. Fermi GRB 240805A: Global MASTER-Net observations report
  46. Swift GRB 240805A: Global MASTER-Net observations report
  47. Fermi Gamma-ray Burst Monitor trigger 744558410/240805574 is not a GRB
  48. GRB 240805A: Swift-XRT refined Analysis
  49. GRB 240805B: Swift detection of a burst
  50. GRB 240805A: Fermi-LAT detection
  51. GRB 240805A: INTEGRAL spectral analysis
  52. EP240801a: Continued optical observations at ZTSh (CraO)
  53. GRB 240805A: A long GRB detected by INTEGRAL
  54. GRB 240805A: Swift detection of a burst
  55. GRB 240805A: Fermi GBM Final Real-time Localization
  56. Fermi GRB 240804A: Global MASTER-Net observations report
  57. EP240802a: Montarrenti Observatory optical upper limit
  58. GRB 240804A: Fermi GBM Final Real-time Localization
  59. IPN triangulation of GRB 240802A / EP 240802a
  60. Fermi Gamma-ray Burst Monitor trigger 744459130/240804425 is not a GRB
  61. EP240802A: Bassano Bresciano Observatory upper limit
  62. GRB 240802A: SVOM/GRM observation
  63. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  64. GRB 240802A: AstroSat CZTI detection of a long burst
  65. EP240801a: further SAO RAS optical observations
  66. EP240801a: optical observations at CrAO and AbAO
  67. EP240801a: Leavitt Observatory optical observations
  68. EP240801a: SAO RAS optical observations
  69. GRB 240801B: AstroSat CZTI Updated classification - likely a solar flare
  70. GRB 240727C: SVOM/GRM observation
  71. Fermi GBM trigger 744179961 / 240801194 can not be confirmed as a GRB
  72. GRB 240730A: Swift-BAT refined analysis
  73. EP240801a: KAIT optical counterpart observations
  74. GRB 240801B: AstroSat CZTI detection of a bright long burst
  75. Fermi GRB 240801A: Global MASTER-Net observations report
  76. GRB 240801A: Fermi GBM Final Real-time Localization
  77. GRB 240730C: AstroSat CZTI detection of a long burst
  78. GRB 240731A: Fermi GBM Final Localization
  79. GRB 240731A: AstroSat CZTI detection
  80. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  81. GRB240730A: BOOTES-5/JGT early optical upper limit
  82. Fermi Gamma-ray Burst Monitor trigger 744061103/240730818 is not a GRB
  83. Fermi GRB 240730B: Global MASTER-Net observations report
  84. GRB 240730B: Fermi GBM Final Real-time Localization
  85. Swift GRB 240730A: Global MASTER-Net observations report
  86. GRB 240730A: Swift-XRT refined Analysis
  87. GRB 240715A: Swift-XRT afterglow detection
  88. GRB 240730A: KAIT Optical Upper Limit
  89. GRB 240727C: GRBAlpha detection
  90. GRB 240730A: Swift/UVOT Upper Limits
  91. GRB 240730A: Enhanced Swift-XRT position
  92. GRB 240730A: Swift detection of a burst
  93. GRB 240727A: Swift-BAT refined analysis
  94. Fermi Gamma-ray Burst Monitor trigger 743953682/240729575 is not a GRB
  95. GRB 240727A: observations of optical counterpart.
  96. GRB 240727B: Swift-XRT observations
  97. Fermi GRB 240727A: Global MASTER-Net observations report
  98. GRB 240727A: Swift/UVOT detection
  99. Fermi Gamma-ray Burst Monitor trigger 743868421/240728588 is not a GRB
  100. GRB 240727A: Correction to time in GCN36960

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