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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"

36192 results found.

  1. GRB 240727A: Enhanced Swift-XRT position
  2. GRB 240727B: Fermi GBM Observation
  3. GRB 240727B: Swift ToO observations
  4. GRB 240727B: Swift/BAT-GUANO arcminute localization of a long burst
  5. GRB 240726A: SVOM/GRM observation
  6. GRB 240727B: AstroSat CZTI detection
  7. GRB 240726B: AstroSat CZTI detection of a short burst
  8. GRB240727A: Skynet Optical Afterglow Observations
  9. GRB 240727A: TRT optical afterglow detection
  10. GRB 240727A: KAIT Optical Afterglow Candidate
  11. GRB 240727A: Swift detection of a burst
  12. GRB 240726A: AstroSat CZTI detection of a short burst
  13. GRB 240726A: Fermi GBM Final Real-time Localization
  14. Swift Trigger 1244778 is not a GRB
  15. GRB 240720A: Swift-BAT refined analysis
  16. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  18. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  19. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  20. GRB 240720B: SVOM/GRM observation
  21. GRB 240721A: Fermi GBM Final Real-time Localization
  22. GRB 240720B: AstroSat CZTI detection of a short burst
  23. Fermi GRB 240720A: Global MASTER-Net observations report
  24. GRB 240720A: AstroSat CZTI detection
  25. GRB 240720A: Fermi GBM observation
  26. GRB 240720A: Swift detection of a burst
  27. Konus-Wind detection of GRB 240718A
  28. GRB 240713A: SVOM/GRM observation
  29. Fermi GRB 240718A: Global MASTER-Net observations report
  30. GRB 240718A: Fermi GBM Observation
  31. GRB 240718A: Fermi-LAT Detection
  32. GRB 240718A: SVOM/GRM observation
  33. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  34. GRB 240718A: Fermi GBM Final Real-time Localization
  35. GRB 240712A: Swift-BAT refined analysis
  36. GRB 240716A: GECAM-B detection of a long burst
  37. SVOM/GRM In-Flight Trigger of GRB 240716A
  38. GRB 240713A: 2.2m CAHA optical limit
  39. GRB 240715A: Swift/UVOT observations of the XRT sources.
  40. GRB 240715A: Swift-XRT observations
  41. GRB240713A: Swift/UVOT Upper LImits
  42. GRB 240715A: GECAM-C detection of a short burst
  43. Konus-Wind detection of GRB 240715A
  44. GRB 240713A: Swift-XRT observations
  45. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  46. GRB 240712A: Swift-XRT refined Analysis
  47. SVOM/GRM In-Flight Trigger of GRB 240715A
  48. GRB 240713A: LAST optical upper limit
  49. GRB 240715A: Swift ToO observations
  50. Fermi GRB 240715A: Global MASTER-Net observations report
  51. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  52. GRB 240715A: Fermi GBM Observation
  53. GRB 240712A ATCA radio observations
  54. GRB240715A: GRANDMA Optical Upper Limits
  55. IPN triangulation of GRB 240715A (short)
  56. GRB 240712A: Swift/UVOT Upper Limits
  57. GRB 240715A: Fermi GBM Final Real-time Localization
  58. GRB 240713A: Tiled Swift observations
  59. GRB 240713A: J-band upper limit from WINTER
  60. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  61. GRB 240713A: JinShan optical upper limits
  62. GRB 240713A: OHP/T120 optical upper limit
  63. GRB240713A: X-ray follow-up observation with EP-FXT
  64. GRB 240713B: AstroSat CZTI detection of a long burst
  65. Fermi Sub-threshold Observation of GRB240713A
  66. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  67. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  68. GRB 240712A: Swift detection of a burst
  69. GRB 240711A: Fermi GBM Final Real-time Localization
  70. EP240708a: KAIT optical upper limit
  71. Fermi GRB 240710A: Global MASTER-Net observations report
  72. GRB 240710A: Fermi GBM Final Real-time Localization
  73. EP240708a: SVOM/C-GFT optical upper limit
  74. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  75. GRB 240705A: Fermi GBM Final Real-time Localization
  76. Konus-Wind detection of GRB 240627A
  77. IPN triangulation of GRB 240628B (short)
  78. EP240703a: KAIT optical upper limit
  79. EP240703a: BTA observations
  80. EP240703a/GRB 240703A: TRT optical candidate likely not real
  81. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  82. IPN triangulation of GRB 240627A
  83. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  84. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  85. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  86. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  87. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  88. Fermi GRB 240702A: Global MASTER-Net observations report
  89. GRB 240702A: Fermi GBM Final Real-time Localization
  90. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  91. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  92. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  93. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  94. Fermi GRB 240629A: Global MASTER-Net observations report
  95. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  96. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  97. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  98. GRB 240629A: Fermi GBM Final Real-time Localization
  99. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  100. IPN triangulation of GRB 240619C

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