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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"

37346 results found.

  1. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  2. GRB 240718A: Fermi GBM Final Real-time Localization
  3. GRB 240712A: Swift-BAT refined analysis
  4. GRB 240716A: GECAM-B detection of a long burst
  5. SVOM/GRM In-Flight Trigger of GRB 240716A
  6. GRB 240713A: 2.2m CAHA optical limit
  7. GRB 240715A: Swift/UVOT observations of the XRT sources.
  8. GRB 240715A: Swift-XRT observations
  9. GRB240713A: Swift/UVOT Upper LImits
  10. GRB 240715A: GECAM-C detection of a short burst
  11. Konus-Wind detection of GRB 240715A
  12. GRB 240713A: Swift-XRT observations
  13. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  14. GRB 240712A: Swift-XRT refined Analysis
  15. SVOM/GRM In-Flight Trigger of GRB 240715A
  16. GRB 240713A: LAST optical upper limit
  17. GRB 240715A: Swift ToO observations
  18. Fermi GRB 240715A: Global MASTER-Net observations report
  19. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  20. GRB 240715A: Fermi GBM Observation
  21. GRB 240712A ATCA radio observations
  22. GRB240715A: GRANDMA Optical Upper Limits
  23. IPN triangulation of GRB 240715A (short)
  24. GRB 240712A: Swift/UVOT Upper Limits
  25. JinShan confirmation of the EP-WXT source triggered on July 14th due to a flaring star
  26. GRB 240715A: Fermi GBM Final Real-time Localization
  27. GRB 240713A: Tiled Swift observations
  28. GRB 240713A: J-band upper limit from WINTER
  29. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  30. GRB 240713A: JinShan optical upper limits
  31. GRB 240713A: OHP/T120 optical upper limit
  32. GRB240713A: X-ray follow-up observation with EP-FXT
  33. GRB 240713B: AstroSat CZTI detection of a long burst
  34. GRB240713A: Optical upper limit with Kinder observations
  35. Fermi Sub-threshold Observation of GRB240713A
  36. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  37. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  38. GRB 240712A: Swift detection of a burst
  39. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  40. GRB 240711A: Fermi GBM Final Real-time Localization
  41. EP240708a: KAIT optical upper limit
  42. Fermi GRB 240710A: Global MASTER-Net observations report
  43. GRB 240710A: Fermi GBM Final Real-time Localization
  44. EP240708a: SVOM/C-GFT optical upper limit
  45. EP240708a: Optical upper limits with Kinder observations
  46. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  47. GRB 240705A: Fermi GBM Final Real-time Localization
  48. Konus-Wind detection of GRB 240627A
  49. IPN triangulation of GRB 240628B (short)
  50. EP240703a: KAIT optical upper limit
  51. EP240703a: BTA observations
  52. EP240703c: Kinder optical follow-up and Swift XRT observations
  53. EP240703a: Liverpool Telescope optical follow-up observations
  54. EP240703a/GRB 240703A: TRT optical candidate likely not real
  55. EP240703a: Kinder optical follow-up observations
  56. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  57. IPN triangulation of GRB 240627A
  58. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  59. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  60. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  61. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  62. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  63. Fermi GRB 240702A: Global MASTER-Net observations report
  64. GRB 240702A: Fermi GBM Final Real-time Localization
  65. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  66. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  67. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  68. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  69. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  70. Fermi GRB 240629A: Global MASTER-Net observations report
  71. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  72. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  73. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  74. GRB 240629A: Fermi GBM Final Real-time Localization
  75. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  76. IPN triangulation of GRB 240619C
  77. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  78. GRB 240627A: NuSTAR Detection of the long GRB
  79. GRB 240615A: SAI CMO J- band observations
  80. GRB 240627A: AstroSat CZTI detection
  81. EP240626a: Montarrenti Observatory optical upper limit
  82. EP240626a: KAIT optical upper limit
  83. GRB 240624A: Swift-BAT refined analysis
  84. Konus-Wind detection of GRB 240619A
  85. Fermi GRB 240625B: Global MASTER-Net observations report
  86. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  87. GRB 240625B: Fermi GBM Final Real-time Localization
  88. GRB 240625A: Fermi GBM Observation
  89. GRB 240624B: GRBAlpha detection
  90. GRB 240625A: Fermi GBM Final Real-time Localization
  91. GRB240624A: Fermi GBM Observation
  92. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  94. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  95. Swift GRB 240624A: Global MASTER-Net observations report
  96. GRB240615A: Gemini-North observations of the BAT and XRT positions
  97. Fermi GRB 240624A: Global MASTER-Net observations report
  98. GRB 240624B: Fermi GBM Final Real-time Localization
  99. GRB240615A: Gemini-North observations of the BAT and XRT positions
  100. GRB 240624A: Fermi GBM Final Real-time Localization

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