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"

27245 results found.

  1. GRB 241104A: COLIBRÍ Upper Limits on the Optical Counterpart
  2. GRB 241104A: SVOM/GRM observation
  3. EP241104a: EP detection of GRB 241104A X-ray emission
  4. GRB 241104A : Detection and localization by SVOM/ECLAIRs
  5. Fermi GRB 241104A: Global MASTER-Net observations report
  6. GRB 241104A: Fermi GBM Final Real-time Localization
  7. EP241101a: EP-FXT observations update
  8. EP241103a: GIT optical upper limit
  9. EP241021a: OHP/T193 further optical observations
  10. LIGO/Virgo/KAGRA S241104a: Retraction of GW compact binary merger candidate
  11. Fermi trigger No 752365806: Global MASTER-Net observations report
  12. EP241103a: GOTO optical upper limit
  13. EP241101a: Possible detection of an optical counterpart with FTW
  14. EP241101a: Optical upper limits with Kinder observations
  15. EP241103a: Gemini optical limits
  16. EP241103a: EP observation update
  17. LIGO/Virgo/KAGRA S241102br: MASTER observations and OT detection
  18. LIGO/Virgo/KAGRA S241102br: EP-WXT X-ray follow-up and flux limits
  19. GRB 241030A: Swift-UVOT observations of the optical prompt flare
  20. EP241103a: GSP optical upper limit
  21. EP241103A: LCO optical observations
  22. EP241103a: Global MASTER-Net observations report
  23. EP241103a: an X-ray transient detected by Einstein Probe
  24. GRB 241030A: Rapid release of TESS data.
  25. EP241101a: Global MASTER-Net observations report
  26. EP241101a: BOOTES-7 optical upper limit
  27. GRB241030A: OHP/T193 optical observations
  28. EP241030a: Futher EP-FXT observation of the X-ray Afterglow of GRB 241030A
  29. EP241101a: EP-WXT detection of a fast X-ray transient
  30. Swift GRB 241101A: Global MASTER-Net observations report
  31. GRB 241101A: FRAM-ORM optical limit
  32. GRB 241101A: Swift-BAT refined analysis
  33. EP241021a: Liverpool Telescope optical follow-up observations
  34. GRB 241030B: Swift-XRT refined Analysis
  35. GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
  36. EP241030a: EP/FXT observation of GRB 241030A X-ray Afterglow
  37. GRB 241101A: Swift detection of a burst
  38. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  39. EP241021a: OHP/T193 optical observations
  40. GRB 241030A: Palomar 1-m telescope COSMOS optical observations
  41. GRB 241030B: Montarrenti Observatory optical upper limit
  42. GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
  43. EP241026b: Liverpool Telescope optical follow-up
  44. Fermi trigger No 752083996: Global MASTER-Net observations report
  45. GRB 241030A: Fermi GBM Observation
  46. GRB 241030B : GIT optical upper limits
  47. GRB 241030B: LCOGT Optical Upper Limits
  48. GRB 241030B: Swift-BAT refined analysis
  49. GRB 241030A: Swift-BAT refined analysis
  50. GRB 241029A: COLIBRI Detection of the Optical Counterpart
  51. GRB 241030B: Swift/UVOT Detection
  52. EP EP241030a: Global MASTER-Net observations report
  53. GRB 241029A: LCO optical detection
  54. Fermi trigger No 752006065: Global MASTER-Net observations report
  55. GRB 241030B: GTC/OSIRIS+ tentative spectroscopic redshift z = 2.82
  56. Swift GRB241030.77: Global MASTER-Net observations report
  57. GRB 241030B: SVOM/GRM observation
  58. GRB 241030B : MITSuME Akeno optical upper limits
  59. GRB 241030A: COLIBRI Continuing Detection of the Afterglow
  60. GRB 241030B: SVOM/VT optical afterglow observations
  61. GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
  62. EP241030a: EP detection of GRB 241030A X-ray Afterglow
  63. GRB241030B: Fermi GBM Observation
  64. GRB 241029A: SVOM/VT optical afterglow observations
  65. GRB 241030B: optical observations from the INAF Asiago Observatory
  66. GRB241030B: GRANDMA/TAROT Upper Limit
  67. GRB 241030A: Swift-XRT refined Analysis
  68. GRB 241030B: SAO RAS optical observations
  69. GRB 241030B: AKO Optical Afterglow Detection
  70. GRB 241030B: Nanshan/HMT optical afterglow detection
  71. GRB 241030B: SVOM/ECLAIRs detection of a burst
  72. GRB 241030B: Swift detection of a burst
  73. GRB 241030B: Fermi GBM Final Real-time Localization
  74. GRB 241030A: Fermi-LAT detection
  75. Fermi GRB 241030A: Global MASTER-Net observations report
  76. GRB 241030A: AKO Optical Afterglow Detection
  77. Swift GRB 241030A: Global MASTER-Net observations report
  78. GRB 241030A: Swift/UVOT Detection
  79. EP 241021a: further Swift-XRT observations and X-ray counterpart detection
  80. GRB 241030A: SVOM/GRM observation
  81. GRB 241026A: Swift-BAT refined analysis
  82. GRB 241030A: SVOM/C-GFT optical observations
  83. EP241026b: EP-FXT follow-up observation
  84. GRB 241030A: Multiband optical detection with Mephisto
  85. GRB 241030A: SVOM/VT optical afterglow observations
  86. GRB 241030A : MITSuME Akeno optical afterglow detection
  87. GRB 241029A: GROWTH-India Telescope optical follow up
  88. GRB 241030A: TRT optical observations
  89. GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
  90. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  91. GRB 241030A: Swift detection of a burst with a bright optical counterpart
  92. GRB 241030A: Fermi GBM Final Real-time Localization
  93. GRB 241029A: GTC/OSIRIS+ spectroscopic redshift z=1.072
  94. EP241021a: ATCA radio observations
  95. GRB 241026A: Swift/UVOT Upper Limits
  96. GRB 241029A: Fermi GBM Observation
  97. GRB 241029A: AKO Optical Afterglow Detection
  98. GRB 241029A: GOTO optical afterglow detection
  99. GRB 241029A: MASTER early optical counterpart detection
  100. GRB 241029A: Xinglong-2.16m optical afterglow confirmation

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