Skip to main content
New! Super-Kamiokande JSON Notices and Schema v4.5.0. 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"

1593 results found.

  1. GRB 241025A: VIRT Optical Upper Limit
  2. GRB 241112B: Mephisto further optical observations
  3. GRB 241117A: Swift/BAT-GUANO localization skymap of a burst
  4. GRB 241117A: SVOM/GRM observation of a short burst with extended emission
  5. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  6. GRB 241113B: Mephisto upper limits
  7. GRB 241115D / EP 241115a: SVOM/GRM observation
  8. GRB 241113B: KAIT Optical Afterglow Candidate
  9. GRB 241113B: J-band upper limit from WINTER
  10. GRB 241113B: Swift-XRT observations
  11. EP241113b/GRB 241113B: EP detection of GRB 241113B
  12. GRB 241113B: SVOM/GRM observation
  13. EP241107a: SOAR upper limits
  14. Konus-Wind detection of GRB 241107A (short/hard)
  15. GRB 241113B: Swift ToO observations
  16. GRB 241112B: GMG Optical Upper Limit
  17. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  18. SVOM/GRM detection of a short burst from SGR 1E1841-045
  19. GRB 241105A: ATCA Radio Upper Limits
  20. GRB 241112B: AbAO optical upper limit
  21. GRB 241107A: GROWTH-India telescope optical upper limit
  22. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  23. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  24. GRB 241112B: Swift-XRT afterglow detection
  25. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  26. GRB 241112B: SVOM/GRM observation
  27. GRB 241112B: SVOM/VT afterglow detection
  28. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  29. GRB 241112B: Mephisto optical upper limits
  30. GRB 241112B: GOTO optical upper limits
  31. GRB 241112B: Swift ToO observations
  32. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  33. GRB 241107A: INTEGRAL IBIS localization
  34. IPN triangulation of GRB 241107A (short/hard)
  35. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  36. GRB 241025A: VZLUSAT-2 detection
  37. GRB 241018A: cubesat Avion detection
  38. EP241107a: AbAO optical upper limit
  39. GRB 241108A: Further COLIBRÍ Upper Limits on the Optical Counterpart
  40. GRB 241108A: Swift-XRT observations
  41. EP241107A: MASTER optical observations of xray transient
  42. EP241107a: KAIT optical observations
  43. GRB 241108A: Swift ToO observations
  44. GRB 241108A: COLIBRÍ Upper Limits on the Optical Counterpart
  45. GRB 241108A : a likely weak long GRB detected by SVOM/ECLAIRs
  46. EP241107a: Kinder optical follow-up observations
  47. GRB 241025A: radio detection with the VLA
  48. GRB 241104A: CALET Gamma-Ray Burst Monitor detection
  49. GRB 241107A: SVOM/GRM detection of a short burst
  50. GRB 241105A: EP-FXT follow-up observations
  51. GRB 241105A: SVOM/GRM observation
  52. EP241107a: GIT optical observations
  53. EP241107a: SVOM/C-GFT optical observations
  54. GRB 241025A: LBT optical observations
  55. GRB 241105A: VLT/FORS2 optical afterglow rapid fading
  56. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  57. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  58. GRB 241105A: BOOTES-7 optical detection
  59. GRB 241030A: Mondy optical observations
  60. GRB 241105A: Fermi GBM Observation of a Short Burst with Extended Emission
  61. GRB 241105A: SVOM/VT optical afterglow observations
  62. GRB 241104A: Swift-XRT observations
  63. GRB 241104A: Fermi GBM Observation
  64. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  65. GRB 241104A: SVOM/VT optical candidate
  66. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  67. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  68. GRB 241104A: SVOM/GRM observation
  69. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  70. GRB 240821A: further radio observations with the VLA
  71. GRB 241030A: GRBAlpha detection
  72. GRB 241029A: GRBAlpha detection
  73. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  74. GRB 241030B: Montarrenti Observatory optical upper limit
  75. GRB 241030A: Fermi GBM Observation
  76. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  77. GRB 241030B: SVOM/GRM observation
  78. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  79. GRB 241030B: SVOM/VT optical afterglow observations
  80. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  81. GRB241030B: Fermi GBM Observation
  82. GRB 241029A: SVOM/VT optical afterglow observations
  83. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  84. GRB 241030B: optical observations from the INAF Asiago Observatory
  85. GRB241030B: GRANDMA/TAROT Upper Limit
  86. GRB 241030B: AKO Optical Afterglow Detection
  87. GRB 241030B: Nanshan/HMT optical afterglow detection
  88. GRB 241030B: SVOM/ECLAIRs detection of a burst
  89. Konus-Wind detection of GRB 241030A
  90. GRB 241030A: Fermi-LAT detection
  91. GRB 240912A: radio detection with the VLA
  92. GRB 241030A: AKO Optical Afterglow Detection
  93. GRB 241030A: SVOM/GRM observation
  94. GRB 241030A: SVOM/C-GFT optical observations
  95. GRB 241030A: SVOM/VT optical afterglow observations
  96. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  97. GRB 241029A: GROWTH-India Telescope optical follow up
  98. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  99. GRB 241029A: Swift-XRT observations
  100. GRB 241029A: Fermi GBM Observation

Advanced

Download all Circulars as a .tar.gz archive:
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