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"

45728 results found.

  1. GRB 241117A: Fermi GBM Final Real-time Localization
  2. GRB 241115C: Fermi GBM Observation
  3. GRB 241115A: Swift-XRT afterglow detection
  4. LIGO/Virgo/KAGRA S241116cq: Identification of a GW compact binary merger candidate
  5. EP241115a/GRB 241115D: Optical upper limits with Kinder observations
  6. GRB 241115A: Mephisto upper limits
  7. GRB 241113B: Mephisto upper limits
  8. EP241115a/GRB 241115D: Swift/XRT follow-up observation
  9. GRB 241115D / EP 241115a: SVOM/GRM observation
  10. The EP-WXT trigger 01709120856 is likely a flaring star
  11. EP241113a: Swift XRT weak detection
  12. GRB 241115A: Fermi GBM Observation
  13. GRB 241115A: LCOGT Optical Upper Limits
  14. GRB 241115C: Swift/BAT-GUANO localization skymap of a burst
  15. Fermi GRB 241115B: Global MASTER-Net observations report
  16. LIGO/Virgo/KAGRA S241114bi: Updated Sky localization and EM Bright Classification
  17. EP241115a: Global MASTER-Net observations report
  18. GRB 241115B: Fermi GBM Final Real-time Localization
  19. LIGO/Virgo/KAGRA S241113p: Updated Sky localization
  20. EP241115a: EP detection of a fast X-ray transient
  21. EP241113a: No Detection in Fermi-GBM Observations
  22. Swift GRB 241115A: Global MASTER-Net observations report
  23. Fermi GRB 241115A: Global MASTER-Net observations report
  24. GRB 241115A: Swift detection of a burst
  25. GRB 241115A: Fermi GBM Final Real-time Localization
  26. EP 241113a: LBT possible optical counterpart
  27. GRB 241113B: KAIT Optical Afterglow Candidate
  28. LIGO/Virgo/KAGRA S241114bi: Upper limits from Fermi-GBM Observations
  29. LIGO/Virgo/KAGRA S241114bi: Coverage and upper limits from MAXI/GSC observations
  30. GRB 241113A: Swift-BAT refined analysis
  31. LIGO/Virgo/KAGRA S241114bi: Identification of a GW compact binary merger candidate
  32. GRB 241113A: PRIME near-infrared upper limits
  33. Fermi GRB 241114A: Global MASTER-Net observations report
  34. EP241113a: Global MASTER-Net observations report
  35. GRB 241114A: Fermi GBM Final Real-time Localization
  36. GRB 241113B: J-band upper limit from WINTER
  37. GRB 241113A: J-band observations with WINTER
  38. EP241113a : J-band observations with WINTER
  39. GRB 241030A: LCO optical observation
  40. GRB 241113B: Swift-XRT observations
  41. IceCube-241113A: Upper limits from a search for additional neutrino events in IceCube
  42. GRB 241113A: 1.6m Mephisto and 50cm array optical upper limits
  43. GRB 241113A: KAIT optical observations
  44. EP241113b: Global MASTER-Net observations report
  45. EP241113b/GRB 241113B: EP detection of GRB 241113B
  46. Fermi-LAT gamma-ray observations of IceCube-241113A
  47. GRB 241113B: SVOM/GRM observation
  48. EP241113a: EP on-board trigger and autonomous follow-up observation
  49. LIGO/Virgo/KAGRA S241114y: Identification of a GW compact binary merger candidate
  50. GRB 241113A: Swift-XRT refined Analysis
  51. EP241107a: SOAR upper limits
  52. GRB 241113A: Swift/UVOT Detection
  53. GRB 241113A: REM detection of the optical/NIR afterglow
  54. Konus-Wind detection of GRB 241107A (short/hard)
  55. LIGO/Virgo/KAGRA S241113p: Identification of a GW compact binary merger candidate
  56. Fermi Gamma-ray Burst Monitor trigger 753166198/241113201 is not a GRB
  57. GRB 241113B: Swift ToO observations
  58. GRB 241113A: LCO optical observations
  59. IceCube-241113A - IceCube observation of a high-energy neutrino candidate track-like event
  60. GRB 241112B: GMG Optical Upper Limit
  61. GRB 241113A: Enhanced Swift-XRT position
  62. GRB241113A: LCOGT (40-cm) optical counterpart detection
  63. GRB 241113B : detection of a long GRB by SVOM/ECLAIRs
  64. GRB 241113A: MASTER010615.66-224018.2 optical counterpart detection
  65. GRB 241113A: Swift detection of a burst with an optical counterpart
  66. Swift GRB241113.33: Global MASTER-Net observations report
  67. SVOM/GRM detection of a short burst from SGR 1E1841-045
  68. Fermi trigger No 753166198: Global MASTER-Net observations report
  69. LIGO/Virgo/KAGRA S241111bn: Updated Sky localization
  70. GRB 241105A: ATCA Radio Upper Limits
  71. GRB 241112B: AbAO optical upper limit
  72. GRB 241107A: GROWTH-India telescope optical upper limit
  73. IceCube Alert 241113.02: Global MASTER-Net observations report
  74. Fermi GRB 241112A: Global MASTER-Net observations report
  75. Fermi-GBM Sub-Threshold Detection of GRB 241112B
  76. GRB 241112B: Optical afterglow detection confirmation in revisiting the Mephisto data
  77. GRB 241112B: Swift-XRT afterglow detection
  78. GRB 241112B: LCO optical detection of the SVOM/VT candidate
  79. GRB 241112B: SVOM/GRM observation
  80. GRB 241112B: SVOM/VT afterglow detection
  81. Fermi Gamma-ray Burst Monitor trigger 752995908/241111230 (GRB 241111A) is not a GRB
  82. GRB 241107A: Swift/BAT candidate arcminute localization of a short burst
  83. GRB 241112B: Mephisto optical upper limits
  84. GRB 241112B: GOTO optical upper limits
  85. GRB 241112B: Swift ToO observations
  86. GRB 241112B : detection of a long GRB by SVOM/ECLAIRs
  87. GRB 241107A: INTEGRAL IBIS localization
  88. EP241107a: EP-FXT follow-up observations
  89. GRB 241112A: Fermi GBM Final Real-time Localization
  90. LIGO/Virgo/KAGRA S241110br: NED Galaxies in the Localization Volume
  91. LIGO/Virgo/KAGRA S241109bn: ATLAS observations and discovery of the potential counterpart AT2024aawt
  92. GRB 241105A: VLT/FORS2 refined spectroscopic redshift z = 2.681
  93. LIGO/Virgo/KAGRA S241111bn: Identification of a GW compact binary merger candidate
  94. IPN triangulation of GRB 241107A (short/hard)
  95. GRB 241107A: INTEGRAL/IBIS/PICsIT detection of a short burst
  96. GRB 241025C: VZLUSAT-2 detection
  97. GRB 241025A: VZLUSAT-2 detection
  98. GRB 241018A: cubesat Avion detection
  99. Fermi trigger No 752990530: Global MASTER-Net observations report
  100. GRB 241111A: Fermi GBM Final Real-time Localization

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