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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"

36384 results found.

  1. GRB 240726A: SVOM/GRM observation
  2. GRB 240727B: AstroSat CZTI detection
  3. GRB 240726B: AstroSat CZTI detection of a short burst
  4. GRB240727A: Skynet Optical Afterglow Observations
  5. GRB 240727A: TRT optical afterglow detection
  6. GRB 240727A: KAIT Optical Afterglow Candidate
  7. GRB 240727A: Swift detection of a burst
  8. GRB 240726A: AstroSat CZTI detection of a short burst
  9. IceCube-240725A: Upper limits from a search for additional neutrino events in IceCube
  10. GRB 240726A: Fermi GBM Final Real-time Localization
  11. Swift Trigger 1244778 is not a GRB
  12. GRB 240720A: Swift-BAT refined analysis
  13. IceCube-240721A: Upper limits from a search for additional neutrino events in IceCube
  14. LIGO/Virgo/KAGRA S240716b: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S240703ad: Upper limits from Swift/BAT-GUANO
  16. Fermi Gamma-ray Burst Monitor trigger 743271526/240721680 is not a GRB
  17. Fermi Gamma-ray Burst Monitor trigger 743243582/240721356 (GRB 240721A) is not a GRB
  18. GRB 240720B: SVOM/GRM observation
  19. GRB 240721A: Fermi GBM Final Real-time Localization
  20. GRB 240720B: AstroSat CZTI detection of a short burst
  21. Fermi GRB 240720A: Global MASTER-Net observations report
  22. GRB 240720A: AstroSat CZTI detection
  23. GRB 240720A: Fermi GBM observation
  24. GRB 240720A: Swift detection of a burst
  25. Konus-Wind detection of GRB 240718A
  26. GRB 240713A: SVOM/GRM observation
  27. Fermi GRB 240718A: Global MASTER-Net observations report
  28. GRB 240718A: Fermi GBM Observation
  29. GRB 240718A: Fermi-LAT Detection
  30. GRB 240718A: SVOM/GRM observation
  31. GRB 240718A: BALROG localization (Fermi Trigger 742976945 / GRB 240718270)
  32. GRB 240718A: Fermi GBM Final Real-time Localization
  33. GRB 240712A: Swift-BAT refined analysis
  34. GRB 240716A: GECAM-B detection of a long burst
  35. SVOM/GRM In-Flight Trigger of GRB 240716A
  36. GRB 240713A: 2.2m CAHA optical limit
  37. GRB 240715A: Swift/UVOT observations of the XRT sources.
  38. GRB 240715A: Swift-XRT observations
  39. GRB240713A: Swift/UVOT Upper LImits
  40. GRB 240715A: GECAM-C detection of a short burst
  41. Konus-Wind detection of GRB 240715A
  42. GRB 240713A: Swift-XRT observations
  43. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  44. GRB 240712A: Swift-XRT refined Analysis
  45. SVOM/GRM In-Flight Trigger of GRB 240715A
  46. GRB 240713A: LAST optical upper limit
  47. GRB 240715A: Swift ToO observations
  48. Fermi GRB 240715A: Global MASTER-Net observations report
  49. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  50. GRB 240715A: Fermi GBM Observation
  51. GRB 240712A ATCA radio observations
  52. GRB240715A: GRANDMA Optical Upper Limits
  53. IPN triangulation of GRB 240715A (short)
  54. GRB 240712A: Swift/UVOT Upper Limits
  55. GRB 240715A: Fermi GBM Final Real-time Localization
  56. GRB 240713A: Tiled Swift observations
  57. GRB 240713A: J-band upper limit from WINTER
  58. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  59. GRB 240713A: JinShan optical upper limits
  60. GRB 240713A: OHP/T120 optical upper limit
  61. GRB240713A: X-ray follow-up observation with EP-FXT
  62. GRB 240713B: AstroSat CZTI detection of a long burst
  63. Fermi Sub-threshold Observation of GRB240713A
  64. GRB240713A : The first probable GRB Located on-Board SVOM by ECLAIRs
  65. Fermi Gamma-ray Burst Monitor trigger 742413075/240711744 is not a GRB
  66. GRB 240712A: Swift detection of a burst
  67. GRB 240711A: Fermi GBM Final Real-time Localization
  68. EP240708a: KAIT optical upper limit
  69. Fermi GRB 240710A: Global MASTER-Net observations report
  70. GRB 240710A: Fermi GBM Final Real-time Localization
  71. EP240708a: SVOM/C-GFT optical upper limit
  72. Fermi Gamma-ray Burst Monitor trigger 741911057/240705933 is not a GRB
  73. GRB 240705A: Fermi GBM Final Real-time Localization
  74. Konus-Wind detection of GRB 240627A
  75. IPN triangulation of GRB 240628B (short)
  76. EP240703a: KAIT optical upper limit
  77. EP240703a: BTA observations
  78. EP240703a/GRB 240703A: TRT optical candidate likely not real
  79. EP240703a/GRB 240703A: TRT and JinShan decaying optical afterglow candidate
  80. IPN triangulation of GRB 240627A
  81. GRB 240619A: Host galaxy redshift from VLT/X-shooter
  82. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  83. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  84. The first three GRBs detected by SVOM: GRB 240627B, GRB 240629A and GRB 240702A
  85. GRB 240702A: BALROG localization (Fermi Trigger / GRB 240702885)
  86. Fermi GRB 240702A: Global MASTER-Net observations report
  87. GRB 240702A: Fermi GBM Final Real-time Localization
  88. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  89. Fermi Gamma-ray Burst Monitor trigger 741448122/240630575 is not a GRB
  90. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  91. LIGO/Virgo/KAGRA S240629by: Upper limits from Fermi-GBM Observations
  92. Fermi GRB 240629A: Global MASTER-Net observations report
  93. Fermi Gamma-ray Burst Monitor trigger 741362867/240629589 is not a GRB
  94. Fermi Gamma-ray Burst Monitor trigger 741288821/240628732 is not a GRB
  95. GRB 240629A: BALROG localization (Fermi Trigger 741372837 / GRB 240629704)
  96. GRB 240629A: Fermi GBM Final Real-time Localization
  97. Fermi Gamma-ray Burst Monitor trigger 741356809/240629519 is not a GRB
  98. IPN triangulation of GRB 240619C
  99. GRB 240628A: BALROG localization (Fermi Trigger 741288821 / GRB 240628732)
  100. GRB 240627A: NuSTAR Detection of the long GRB

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