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"

37709 results found.

  1. GRB 260114A: Insight-HXMT/HE detection
  2. GRB 260122B: Swift detection of a burst
  3. EP260119a: Assy AZT-20 optical observations
  4. EP260119a: Mondy and SAO RAS optical upper limits
  5. GRB 260122A: Fermi GBM Final Real-time Localization
  6. Fermi GRB 260120C: Global MASTER-Net observations report
  7. GRB 260120B: Swift-BAT refined analysis
  8. GRB 260120B: Swift-XRT refined Analysis
  9. GRB 251122A / EP251122a: VLT/X-shooter host redshift z = 1.765
  10. GRB 260120B: Fermi GBM Observation
  11. GRB 260120B: Swift/UVOT Detection
  12. GRB 260120B: COLIBRÍ optical upper limits
  13. GRB 260120B: Enhanced Swift-XRT position
  14. GRB 260120B: SVOM/C-GFT optical counterpart detection
  15. GRB 260120C: Fermi GBM Final Real-time Localization
  16. GRB 260101A: 239Alferov CubeSat detection
  17. GRB 260120B: Swift detection of a burst
  18. GRB 260120B: Fermi GBM Final Real-time Localization
  19. EP260119A: Mondy I-Band Observations
  20. Fermi trigger No 790601190: Global MASTER-Net observations report
  21. Fermi trigger No 790570272: Global MASTER-Net observations report
  22. GRB 260114A: Swift/UVOT Upper Limits
  23. GRB 251202A: further radio observations with the VLA
  24. EP260119a: KAIT optical observations
  25. GRB 260120A: Fermi GBM Final Real-time Localization
  26. EP260119a: SAO RAS optical observations
  27. GRB 251208D: SVOM/ECLAIRs refined analysis
  28. GRB 251208D: SVOM/ECLAIRs refined analysis
  29. GRB 260117A: Swift-XRT afterglow detection
  30. GRB 260115A: AstroSat CZTI detection
  31. GRB 260117A: ZTSh optical upper limit
  32. GRB 260110A: SVOM detection of a burst through offline search
  33. GRB 260117A: SVOM/COLIBRÍ (FM-GFT) optical observations
  34. Fermi-LAT Gamma-ray Observations of IceCube-260115A
  35. GRB 260117A: SVOM/VT optical candidate
  36. GRB 260117A: SVOM/C-GFT upper limit
  37. GRB 260117A: Swift-XRT observations
  38. GRB 260117A: Swift ToO observations
  39. GRB 260117A: SVOM detection of a long faint burst
  40. GRB 260115A: GECAM-B observation
  41. GRB 260114A: VLT/MUSE spectroscopic observations
  42. GRB 260111A: COLIBRÍ fading of the optical counterpart candidate
  43. GRB 260114A: VLT/HAWK-I further near-infrared upper limits
  44. IceCube-260115A - IceCube observation of a high-energy neutrino candidate track-like event
  45. GRB 260115A: BALROG localization (Fermi Trigger 790192010 / GRB 260115741)
  46. Fermi GRB 260115A: Global MASTER-Net observations report
  47. GRB 260115A: Fermi GBM Final Real-time Localization
  48. GRB260114A: STEP/T80S optical limits
  49. GRB 251222A: radio detection with the VLA
  50. GRB 260114A: VLT/HAWK-I near-infrared upper limits
  51. Konus-Wind detection of GRB 260114A
  52. GRB 260114A: Swift-XRT refined Analysis
  53. GRB 260114A: 6 GHz VLA observations
  54. GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
  55. GRB 260114A : MITSuME Akeno optical upper limits
  56. GRB 260114A: COLIBRÍ optical upper limits
  57. GRB 260114A: TNG NIR upper limit
  58. GRB 260114A: NOT optical observations
  59. Konus-Wind detection of GRB 251230A / EP251230a
  60. GRB 260114A: SVOM/GRM observation of a short burst
  61. Swift GRB 260114A: Global MASTER-Net observations report
  62. GRB 260114A: GECAM-B observation of a short burst
  63. GRB 260114A: Mondy optical observations
  64. GRB 260114A: Fermi GBM observation
  65. GRB 260112B: GECAM-B observation
  66. GRB 260114A: GMG Optical Observation
  67. Fermi-LAT Gamma-ray Observations of IceCube-260111A
  68. GRB 260114A: Swift detection of a short burst
  69. GRB 260114A: Fermi GBM Final Real-time Localization
  70. Konus-Wind detection of GRB 260101A
  71. GRB 260111A: Swift-XRT observations
  72. Swift Trigger 1439093: is probably not GRB 260113A
  73. GRB 260111A: COLIBRÍ optical afterglow candidate
  74. GRB 260111A: GECAM-B observation of a burst
  75. GRB 260111A: Fermi GBM Observation
  76. Swift Trigger 1434591 is not a GRB
  77. GRB 260111A: GOTO optical upper limits
  78. GRB 260112B: Fermi GBM Final Real-time Localization
  79. GRB 260111A: Swift ToO observations
  80. GRB 251230A: Mondy Optical Observations
  81. GRB 260111A: Swift/BAT-GUANO arcminute localization of a burst
  82. GRB 260112A: Fermi GBM Final Real-time Localization
  83. IceCube-260111A - IceCube observation of a high-energy neutrino candidate track-like event
  84. Fermi GRB 260111A: Global MASTER-Net observations report
  85. GRB 260111A: Fermi GBM Final Real-time Localization
  86. EP260110a: KAIT optical upper limit
  87. GRB 260109C: LCO optical upper limits
  88. GRB 260109C: Kilonova-Catcher optical upper limit
  89. EP260105b / GRB 260105C : Fermi-GBM Sub-Threshold Detection
  90. Swift Trigger 1434591: possible GRB 260109C
  91. GRB 260109B: Fermi GBM Final Real-time Localization
  92. GRB 260102A: Swift-XRT afterglow detection
  93. GRB 260109A: Fermi GBM Final Real-time Localization
  94. GRB 260104A: Swift-BAT refined analysis
  95. GRB 260101A: Swift-BAT refined analysis
  96. Swift GRB 251230A: Global MASTER-Net OT detection
  97. Fermi GRB 260107A: Global MASTER-Net observations report
  98. GRB 260102A: AbAO optical observations
  99. GRB 260107A: Fermi GBM Final Real-time Localization
  100. Fermi GRB 260105A: Global MASTER-Net observations report

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