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"

23690 results found.

  1. GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
  2. GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
  3. GRB 241105A: BOOTES-7 optical detection
  4. Konus-Wind detection of GRB 241105A (short with extended emission)
  5. LIGO/Virgo/KAGRA S241106ba: 1 counterpart neutrino candidate event from an IceCube neutrino search
  6. LIGO/Virgo/KAGRA S241102o: 1 counterpart neutrino candidate event from an IceCube neutrino search
  7. Konus-Wind detection of GRB 241021A
  8. GRB 241105A: SVOM/VT optical afterglow observations
  9. GRB 241105A: Swift-XRT afterglow detection
  10. GRB 241104A: Swift-XRT observations
  11. GRB 241104A: The SVOM/VT candidate in GCN circular 38086 is not an astrophysical source
  12. GRB 241104A: NOT optical non-detection
  13. GRB 241105A: GOTO tentative optical counterpart candidate
  14. GRB 241104A: SVOM/VT optical candidate
  15. GRB 241104A/EP241104a: Optical upper limits with Kinder observations
  16. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  17. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  18. GRB 240821A: further radio observations with the VLA
  19. GRB 241030A: GRBAlpha detection
  20. EP241101a: EP-FXT observations update
  21. EP241103a: GOTO optical upper limit
  22. EP241101a: Optical upper limits with Kinder observations
  23. EP241103a: GSP optical upper limit
  24. EP241103A: LCO optical observations
  25. EP241103a: Global MASTER-Net observations report
  26. EP241101a: Global MASTER-Net observations report
  27. GRB 241029A: GRBAlpha detection
  28. EP241101a: BOOTES-7 optical upper limit
  29. S241102cy: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S241102br: NED Galaxies in the Localization Volume
  31. LIGO/Virgo/KAGRA S241102br: Identification of a GW compact binary merger candidate
  32. Kinder optical follow-up observations of EP241021a, EP241026b, and EP241030a/GRB241030A
  33. EP241101a: EP-WXT detection of a fast X-ray transient
  34. Swift GRB 241101A: Global MASTER-Net observations report
  35. GRB 241030A/EP241030a: TNOT observations of the optical counterpart
  36. EP241021a: Upper limit from Konus-Wind observations
  37. GRB 241101A: Swift-BAT refined analysis
  38. GRB 241030A: further SAO RAS optical observations
  39. GRB 241026A: SAO RAS optical observations
  40. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  41. GRB 241101A: Swift detection of a burst
  42. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  43. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  44. GRB 241030B: Montarrenti Observatory optical upper limit
  45. Fermi trigger No 752083996: Global MASTER-Net observations report
  46. GRB 241030A: SAO RAS optical observations
  47. GRB 241030B: Swift-BAT refined analysis
  48. GRB 241030A: Swift-BAT refined analysis
  49. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  50. EP EP241030a: Global MASTER-Net observations report
  51. GRB 241029A: LCO optical detection
  52. Fermi trigger No 752006065: Global MASTER-Net observations report
  53. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  54. Swift GRB241030.77: Global MASTER-Net observations report
  55. GRB 241030B : MITSuME Akeno optical upper limits
  56. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  57. GRB 241030B: SVOM/VT optical afterglow observations
  58. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  59. GRB 241030B: BTA observations
  60. GRB 241029A: SVOM/VT optical afterglow observations
  61. GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
  62. GRB 241030B: optical observations from the INAF Asiago Observatory
  63. GRB241030B: GRANDMA/TAROT Upper Limit
  64. GRB 241030A: Swift-XRT refined Analysis
  65. GRB 241030B: SAO RAS optical observations
  66. Konus-Wind detection of GRB 241030A
  67. GRB 241030B: Swift detection of a burst
  68. GRB 241030A: Fermi-LAT detection
  69. GRB 240912A: radio detection with the VLA
  70. Fermi GRB 241030A: Global MASTER-Net observations report
  71. Swift GRB 241030A: Global MASTER-Net observations report
  72. GRB 241026A: Swift-BAT refined analysis
  73. GRB 241030A: SVOM/VT optical afterglow observations
  74. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  75. GRB 241030A : MITSuME Akeno optical afterglow detection
  76. GRB 241030A: TRT optical observations
  77. GRB 241030A: Keck/LRIS spectroscopic redshift z = 1.411
  78. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  79. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  80. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  81. GRB 241029A: SAO RAS optical observations
  82. GRB 241026A: SAO RAS optical observations
  83. EP241021a: SAO RAS observations of rebrightening
  84. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  85. MISTRAL@OHP photometric and spectroscopic observations of GRB 241029A
  86. GRB 241026A: Swift/UVOT Upper Limits
  87. GRB 241029A: Swift-XRT observations
  88. GRB 241029A: Fermi GBM Observation
  89. GRB 241029A: GOTO optical afterglow detection
  90. GRB 241029A: MASTER early optical counterpart detection
  91. EP 241026b: LBT possible optical counterpart (brightening source)
  92. GRB 241029A: TRT optical afterglow candidate detection
  93. Fermi trigger No 751861204: Global MASTER-Net observations report
  94. GRB 240821A: Keck/LRIS spectroscopic observations
  95. GRB 241026A: the 100th GRB detected by GRBAlpha
  96. GRB 241026A: TNOT optical counterpart detection
  97. Konus-Wind detection of GRB 241025A
  98. GRB 241026A: GECAM detection
  99. GRB 241025A: further SAO RAS optical observations
  100. GRB 241026A: BTA and Zeiss-1000 optical observations

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