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"

24513 results found.

  1. LIGO/Virgo/KAGRA S240916ar: Updated Sky localization and EM Bright Classification
  2. LIGO/Virgo/KAGRA S240919bn: Identification of a GW compact binary merger candidate
  3. Fermi GRB 240918A: Global MASTER-Net observations report
  4. GRB 240918A: Fermi GBM Final Real-time Localization
  5. EP EP240918a: Global MASTER-Net observations report
  6. EP240918a: YAHPT Optical Upper Limit
  7. GRB 240916A: GRBAlpha detection
  8. GRB 240914B: GRBAlpha detection
  9. GRB 240912A: Swift-BAT refined analysis
  10. IPN triangulation of GRB 240913C / EP 240913a
  11. GRB 240916A: Fermi GBM Observation
  12. LIGO/Virgo/KAGRA S240917cb: Identification of a GW compact binary merger candidate
  13. LIGO/Virgo/KAGRA S240916ar: Identification of a GW compact binary merger candidate
  14. LIGO/Virgo/KAGRA S240915b: NED Galaxies in the Localization Volume
  15. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  16. GRB 240916B: Fermi GBM Final Real-time Localization
  17. GRB 240914B: Fermi GBM Final Localization
  18. The EP-WXT triggers 01709047257 and 01709047278 are not real sources
  19. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  20. EP EP240913a: Global MASTER-Net observations report
  21. LIGO/Virgo/KAGRA S240915b: Coverage and upper limits from MAXI/GSC observations
  22. GRB 240916A: Fermi GBM Final Real-time Localization
  23. LIGO/Virgo/KAGRA S240915bd: Updated Sky localization
  24. LIGO/Virgo/KAGRA S240915bd: Identification of a GW compact binary merger candidate
  25. LIGO/Virgo/KAGRA S240915b: Updated Sky localization and EM Bright Classification
  26. LIGO/Virgo/KAGRA S240915b: Identification of a GW compact binary merger candidate
  27. EP240913a / GRB 240913C INTEGRAL SPI ACS LIGHT CURVE
  28. GRB 240913C: Fermi GBM detection
  29. EP240913A / GRB 240913C: AstroSat CZTI detection
  30. GRB 240914A: SVOM/GRM observation
  31. GRB 240914B: BALROG localization (Fermi Trigger 747990592 / GRB 240914298)
  32. GRB 240914A : An intermediate duration GRB located on-board by SVOM/ECLAIRs.
  33. GRB 240905E: further NOT optical observations
  34. EP240913a: A GRB Event
  35. GRB 240913B: Fermi GBM Final Real-time Localization
  36. Fermi trigger No 747920561: Global MASTER-Net observations report
  37. GRB 240911A: Swift-XRT observations
  38. Fermi GRB 240913A: Global MASTER-Net observations report
  39. GRB 240913A: Fermi GBM Final Real-time Localization
  40. GRB 240912A: Swift-XRT refined Analysis
  41. GRB 240912A: Fermi GBM Observation
  42. Swift GRB 240912A: Global MASTER-Net observations report
  43. GRB 240912B: Fermi GBM Final Real-time Localization
  44. GRB 240912A: NOT optical spectroscopy
  45. GRB 240912A: Fermi GBM Final Real-time Localization
  46. GRB 240910A: Fermi GBM Observation
  47. GRB 240910A: NOT optical observations
  48. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  49. GRB 240910A: JinShan optical observations
  50. GRB 240910A: GOTO candidate optical counterpart
  51. EP240908a: Optical afterglow confirmation
  52. IPN triangulation of GRB 240905B (short)
  53. LIGO/Virgo/KAGRA S240910ci: NED Galaxies in the Localization Volume
  54. GRB 240910A: GRBAlpha detection
  55. GRB 240910B: Fermi GBM Final Real-time Localization
  56. LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
  57. LIGO/Virgo/KAGRA S240910ci: Updated Sky localization and EM Bright Classification
  58. LIGO/Virgo/KAGRA S240910ci: Identification of a GW compact binary merger candidate
  59. GRB 240910A: SVOM/GRM observation
  60. EP240908a: Updates on the WXT detection result around the trigger time
  61. Fermi GRB 240910A: Global MASTER-Net observations report
  62. GRB 240910A: Fermi GBM Final Real-time Localization
  63. LIGO/Virgo/KAGRA S240908bs: Upper limits from Swift/BAT-GUANO
  64. LIGO/Virgo/KAGRA S240907cg: Upper limits from Swift/BAT-GUANO
  65. EP240908a: optical afterglow candidate
  66. EP EP240908a: Global MASTER-Net observations report
  67. GRB 240905B: Fermi GBM Observation
  68. Fermi trigger No 747553301: Global MASTER-Net observations report
  69. GRB 240905B: GOTO optical upper limits
  70. EP240908a: EP detection of a fast X-ray transient
  71. Fermi GRB 240908A: Global MASTER-Net observations report
  72. LIGO/Virgo/KAGRA S240908dg: Updated Sky localization
  73. LIGO/Virgo/KAGRA S240908bs: Updated Sky localization
  74. GRB 240908A: Fermi GBM Final Real-time Localization
  75. LIGO/Virgo/KAGRA S240908dg: Identification of a GW compact binary merger candidate
  76. LIGO/Virgo/KAGRA S240908bs: Identification of a GW compact binary merger candidate
  77. LIGO/Virgo/KAGRA S240907cg: Updated Sky localization
  78. LIGO/Virgo/KAGRA S240907cg: Identification of a GW compact binary merger candidate
  79. GRB 240905B: Swift-XRT observations
  80. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  81. GRB 240905B: Fermi-LAT detection
  82. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  83. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  84. Fermi GRB 240905D: Global MASTER-Net observations report
  85. Fermi GRB 240905A: Global MASTER-Net observations report
  86. GRB 240905E: NOT optical upper limits
  87. GRB 240905E: REM optical/NIR upper limits
  88. GRB 240905E: SVOM/GRM observation
  89. GRB 240905E: LCOGT Optical Upper Limit
  90. GRB 240825A: Montarrenti Observatory optical follow-up observations
  91. Swift GRB 240905E: Global MASTER-Net observations report
  92. GRB 240905E: Swift detection of a burst
  93. GRB 240819A: Optical upper limits from TESS
  94. GRB 240905D: AstroSat CZTI detection
  95. GRB 240905A: SVOM/GRM observation
  96. Fermi GRB 240905B: Global MASTER-Net observations report
  97. GRB 240905D: Fermi GBM Final Real-time Localization
  98. GRB 240905B: AstroSat CZTI detection and localization
  99. GRB 240905C: Fermi GBM Final Real-time Localization
  100. GRB 240905B: 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