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"

27251 results found.

  1. Swift GRB 240912A: Global MASTER-Net observations report
  2. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  3. Fermi Gamma-ray Burst Monitor trigger 747839931/240912555 is not a GRB
  4. GRB 240912B: Fermi GBM Final Real-time Localization
  5. GRB 240912A: NOT optical spectroscopy
  6. GRB 240910A: Redshift from OSIRIS+/GTC
  7. GRB 240912A: Swift detection of a burst with an optical counterpart
  8. GRB 240912A: Fermi GBM Final Real-time Localization
  9. GRB 240910A: Fermi GBM Observation
  10. GRB 240910A: NOT optical observations
  11. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  12. GRB 240910A: JinShan optical observations
  13. GRB 240910A: GOTO candidate optical counterpart
  14. GRB 240710A: SVOM/GRM observation
  15. GRB 240905E: SVOM/VT optical observations
  16. GRB 240910B: Fermi GBM Final Real-time Localization
  17. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  18. GRB 240910A: SVOM/GRM observation
  19. EP240908a: Mondy and AbAO follow-up observations
  20. EP240908a: Updates on the WXT detection result around the trigger time
  21. Fermi GRB 240910A: Global MASTER-Net observations report
  22. GRB 240910A: Fermi GBM Final Real-time Localization
  23. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  24. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  25. EP EP240908a: Global MASTER-Net observations report
  26. GRB 240905B: Fermi GBM Observation
  27. Fermi trigger No 747553301: Global MASTER-Net observations report
  28. GRB 240905B: GOTO optical upper limits
  29. EP240908a: EP detection of a fast X-ray transient
  30. Fermi GRB 240908A: Global MASTER-Net observations report
  31. GRB 240908A: Fermi GBM Final Real-time Localization
  32. GRB 240801A: SVOM/GRM observation
  33. GRB 240905E: GIT optical upper limit
  34. GRB 240905E: Gaoyazi/GOT optical upper limits
  35. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  36. GRB 240905B: Fermi-LAT detection
  37. GRB 240905E: AKO Optical Upper Limit
  38. GRB 240905E: SVOM/C-GFT optical upper limit
  39. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  40. Fermi GRB 240905D: Global MASTER-Net observations report
  41. Fermi GRB 240905A: Global MASTER-Net observations report
  42. GRB 240905E: NOT optical upper limits
  43. GRB 240905E: REM optical/NIR upper limits
  44. GRB 240905E: Swift-XRT refined Analysis
  45. GRB 240905E: SVOM/GRM observation
  46. GRB 240905E: LCOGT Optical Upper Limit
  47. GRB 240905E: Swift/UVOT Upper Limits
  48. GRB 240905E: SAO RAS optical upper limit
  49. GRB 240905E: Nanshan/HMT optical upper limit
  50. Swift GRB 240905E: Global MASTER-Net observations report
  51. GRB 240905E: Swift detection of a burst
  52. GRB 240819A: Optical upper limits from TESS
  53. GRB 240905A: SVOM/GRM observation
  54. Fermi GRB 240905B: Global MASTER-Net observations report
  55. GRB 240905D: Fermi GBM Final Real-time Localization
  56. GRB 240905C: Fermi GBM Final Real-time Localization
  57. GRB 240905B: Fermi GBM Final Real-time Localization
  58. Swift GRB 240904A: Global MASTER-Net observations report
  59. GRB 240905A: Fermi GBM Final Real-time Localization
  60. Fermi Gamma-ray Burst Monitor trigger 747163821/240904729 is not a GRB
  61. Fermi trigger No 747163821: Global MASTER-Net observations report
  62. GRB 240904A: Swift detection of a burst
  63. GRB 240828A: SVOM/GRM observation
  64. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  65. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  66. Fermi Gamma-ray Burst Monitor trigger 240831A is not a GRB
  67. GRB 240828A: GECAM detection
  68. GRB 240831B: Fermi GBM Final Localization
  69. Fermi Gamma-ray Burst Monitor trigger 746882332/240901471 is not a GRB
  70. GRB 240825A: MeerLICHT afterglow detection
  71. Fermi trigger No 746923430: Global MASTER-Net observations report
  72. GRB 240821A: VLT spectroscopic observations
  73. Fermi trigger No 746882332: Global MASTER-Net observations report
  74. GRB 240829B: GRBAlpha detection
  75. GRB240828B: REM optical/NIR upper limits
  76. Fermi trigger No 746816563: Global MASTER-Net observations report
  77. GRB 240831A: Fermi GBM Final Real-time Localization
  78. GRB 240828B: GRANDMA Optical Upper Limit
  79. LIGO/Virgo/KAGRA S240830gn: Coverage and upper limits from MAXI/GSC observations
  80. GRB 240829A: Swift-BAT refined analysis
  81. GRB 240825A: Swift-BAT refined analysis
  82. GRB 240828B: J-band upper limit from WINTER
  83. Fermi trigger No 746684112: Global MASTER-Net observations report
  84. GRB 240828B: GMG Optical Upper Limit
  85. GRB 240828B: SVOM/C-GFT optical upper limit
  86. GRB 240828B: KAIT optical upper limit
  87. Fermi trigger No 746587425: Global MASTER-Net observations report
  88. GRB 240829B: Fermi GBM Final Localization
  89. GRB 240828A: Fermi GBM Observation
  90. GRB 240629A: First GRB Detected by BurstCube
  91. GRB 240825A: SVOM/VT optical detection
  92. GRB 240825A: iTelescope optical observations
  93. GRB 240829A: Swift detection of a burst
  94. Swift GRB240829.16: Global MASTER-Net observations report
  95. GRB 240828A: Fermi-LAT detection
  96. LAT GRB240828.62: Global MASTER-Net observations report
  97. GRB 240828A: AstroSat CZTI detection of a long burst
  98. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  99. GRB 240825A: Upper limits from a neutrino search with IceCube
  100. GRB 240819A as a likely X-Ray Flash

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