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"

36368 results found.

  1. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  2. GRB 240720B: SVOM/GRM observation
  3. GRB 240721A: Fermi GBM Final Real-time Localization
  4. GRB 240720B: AstroSat CZTI detection of a short burst
  5. Fermi GRB 240720A: Global MASTER-Net observations report
  6. GRB 240720A: AstroSat CZTI detection
  7. GRB 240720A: Fermi GBM observation
  8. GRB 240720A: Swift detection of a burst
  9. Konus-Wind detection of GRB 240718A
  10. GRB 240713A: SVOM/GRM observation
  11. Fermi GRB 240718A: Global MASTER-Net observations report
  12. GRB 240718A: Fermi GBM Observation
  13. GRB 240718A: Fermi-LAT Detection
  14. GRB 240718A: SVOM/GRM observation
  15. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  16. GRB 240718A: Fermi GBM Final Real-time Localization
  17. GRB 240712A: Swift-BAT refined analysis
  18. GRB 240716A: GECAM-B detection of a long burst
  19. SVOM/GRM In-Flight Trigger of GRB 240716A
  20. GRB 240713A: 2.2m CAHA optical limit
  21. GRB 240715A: Swift/UVOT observations of the XRT sources.
  22. GRB 240715A: Swift-XRT observations
  23. GRB240713A: Swift/UVOT Upper LImits
  24. GRB 240715A: GECAM-C detection of a short burst
  25. Konus-Wind detection of GRB 240715A
  26. GRB 240713A: Swift-XRT observations
  27. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  28. GRB 240712A: Swift-XRT refined Analysis
  29. SVOM/GRM In-Flight Trigger of GRB 240715A
  30. GRB 240713A: LAST optical upper limit
  31. GRB 240715A: Swift ToO observations
  32. Fermi GRB 240715A: Global MASTER-Net observations report
  33. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  34. GRB 240715A: Fermi GBM Observation
  35. GRB 240712A ATCA radio observations
  36. GRB240715A: GRANDMA Optical Upper Limits
  37. IPN triangulation of GRB 240715A (short)
  38. GRB 240712A: Swift/UVOT Upper Limits
  39. GRB 240715A: Fermi GBM Final Real-time Localization
  40. GRB 240713A: Tiled Swift observations
  41. GRB 240713A: J-band upper limit from WINTER
  42. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  43. GRB 240713A: JinShan optical upper limits
  44. GRB 240713A: OHP/T120 optical upper limit
  45. GRB240713A: X-ray follow-up observation with EP-FXT
  46. GRB 240713B: AstroSat CZTI detection of a long burst
  47. Fermi Sub-threshold Observation of GRB240713A
  48. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  49. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  50. GRB 240712A: Swift detection of a burst
  51. GRB 240711A: Fermi GBM Final Real-time Localization
  52. EP240708a: KAIT optical upper limit
  53. Fermi GRB 240710A: Global MASTER-Net observations report
  54. GRB 240710A: Fermi GBM Final Real-time Localization
  55. EP240708a: SVOM/C-GFT optical upper limit
  56. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  57. GRB 240705A: Fermi GBM Final Real-time Localization
  58. Konus-Wind detection of GRB 240627A
  59. IPN triangulation of GRB 240628B (short)
  60. EP240703a: KAIT optical upper limit
  61. EP240703a: BTA observations
  62. EP240703a/GRB 240703A: TRT optical candidate likely not real
  63. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  64. IPN triangulation of GRB 240627A
  65. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  66. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  67. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  68. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  69. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  70. Fermi GRB 240702A: Global MASTER-Net observations report
  71. GRB 240702A: Fermi GBM Final Real-time Localization
  72. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  73. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  74. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  75. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  76. Fermi GRB 240629A: Global MASTER-Net observations report
  77. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  78. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  79. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  80. GRB 240629A: Fermi GBM Final Real-time Localization
  81. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  82. IPN triangulation of GRB 240619C
  83. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  84. GRB 240627A: NuSTAR Detection of the long GRB
  85. GRB 240615A: SAI CMO J- band observations
  86. GRB 240627A: AstroSat CZTI detection
  87. EP240626a: Montarrenti Observatory optical upper limit
  88. EP240626a: KAIT optical upper limit
  89. GRB 240624A: Swift-BAT refined analysis
  90. Konus-Wind detection of GRB 240619A
  91. Fermi GRB 240625B: Global MASTER-Net observations report
  92. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  93. GRB 240625B: Fermi GBM Final Real-time Localization
  94. GRB 240625A: Fermi GBM Observation
  95. GRB 240624B: GRBAlpha detection
  96. GRB 240625A: Fermi GBM Final Real-time Localization
  97. GRB240624A: Fermi GBM Observation
  98. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  99. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  100. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO

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