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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"

23708 results found.

  1. GRB 240727A: Swift/UVOT detection
  2. Fermi trigger No 743868421: Global MASTER-Net observations report
  3. GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
  4. GRB 240727A: NOT optical observation
  5. GRB 240727A: Swift-XRT refined Analysis
  6. GRB 240720B: GRBAlpha detection
  7. GRB 240718A: GRBAlpha detection
  8. GRB 240710B: GRBAlpha detection
  9. GRB 240627A: GRBAlpha detection
  10. Fermi GRB 240726A: Global MASTER-Net observations report
  11. Swift GRB240727.16: Global MASTER-Net observations report
  12. GRB 240727B: AstroSat CZTI detection
  13. GRB 240727A: TRT optical afterglow detection
  14. GRB 240727A: KAIT Optical Afterglow Candidate
  15. GRB 240727A: Swift detection of a burst
  16. IceCube Alert 240725.22: Global MASTER-Net observations report
  17. Swift Trigger 1244778 is not a GRB
  18. Swift GRB240725.11: Global MASTER-Net observations report
  19. GRB 240720A: Swift-BAT refined analysis
  20. Fermi trigger No 743418632: Global MASTER-Net observations report
  21. Fermi trigger No 743315411: Global MASTER-Net observations report
  22. Fermi trigger No 743345551: Global MASTER-Net observations report
  23. Fermi trigger No 743219692: Global MASTER-Net observations report
  24. IceCube Alert 240721.68: Global MASTER-Net observations report
  25. GRB 240720B: AstroSat CZTI detection of a short burst
  26. Fermi GRB 240720A: Global MASTER-Net observations report
  27. GRB 240720A: AstroSat CZTI detection
  28. GRB 240720A: Swift detection of a burst
  29. Swift GRB240720.02: Global MASTER-Net observations report
  30. Konus-Wind detection of GRB 240718A
  31. Fermi GRB 240718A: Global MASTER-Net observations report
  32. LAT GRB240718.27: Global MASTER-Net observations report
  33. IceCube-Cascade 240714A: TRT optical observations on the EP/FXT positions
  34. GRB 240712A: Swift-BAT refined analysis
  35. GRB 240716A: GECAM-B detection of a long burst
  36. IceCube-Cascade 240714A: X-ray follow-up observation with EP-FXT
  37. GRB 240713A: 2.2m CAHA optical limit
  38. GRB 240715A: GECAM-C detection of a short burst
  39. Konus-Wind detection of GRB 240715A
  40. GRB 240713A: Swift-XRT observations
  41. GRB 240715A: TRT optical upper limit on one Swift/XRT candidate
  42. GRB 240713A: LAST optical upper limit
  43. Fermi GRB 240715A: Global MASTER-Net observations report
  44. GRB 240713A: optical upper limits from the INAF Asiago Observatory
  45. GRB240715A: GRANDMA Optical Upper Limits
  46. IPN triangulation of GRB 240715A (short)
  47. GW s240422ed: Swift UVOT follow-up
  48. GRB 240712A: Swift/UVOT Upper Limits
  49. EP-WXT flaring star and the optical flaring activity during its decay phase
  50. The EP-WXT source triggered on July 14th is likely a flaring star
  51. GRB 240713A: J-band upper limit from WINTER
  52. GRB 240713A: NOT optical upper limits on three EP/FXT candidates
  53. GRB 240713A: JinShan optical upper limits
  54. GRB 240713A: OHP/T120 optical upper limit
  55. GRB240713A: X-ray follow-up observation with EP-FXT
  56. GRB 240713B: AstroSat CZTI detection of a long burst
  57. GRB240713A: Optical upper limit with Kinder observations
  58. Fermi Sub-threshold Observation of GRB240713A
  59. GRB240713A: TAROT and GRANDMA Observations of SVOM/ECLAIRs GRB240713A
  60. EP240708a: GSP optical upper limit
  61. GRB 240712A: Swift detection of a burst
  62. LIGO/Virgo/KAGRA S240711cm: Coverage and upper limits from MAXI/GSC observations
  63. Fermi trigger No 742405878: Global MASTER-Net observations report
  64. Fermi trigger No 742317942: Global MASTER-Net observations report
  65. EP240708a: KAIT optical upper limit
  66. Fermi GRB 240710A: Global MASTER-Net observations report
  67. EP240708a: NOT optical observations
  68. EP240708a: X-ray follow-up observations with EP/FXT and Swift/XRT
  69. EP240708a: Optical upper limits with Kinder observations
  70. EP240708a: EP-WXT detection of a fast X-ray transient
  71. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  72. EP240703b: GSP optical upper limit
  73. EP240703b: TRT optical upper limits
  74. EP240703a: TRT further optical observation
  75. EP240702a: TRT optical upper limits
  76. Konus-Wind detection of GRB 240627A
  77. IPN triangulation of GRB 240628B (short)
  78. EP240703a and EP240703b: Swift/XRT upper limits
  79. LIGO/Virgo/KAGRA S240705at: Identification of a GW compact binary merger candidate
  80. EP240703a: KAIT optical upper limit
  81. EP240703c: Kinder optical follow-up and Swift XRT observations
  82. EP240703a: BOOTES-3 optical upper limit
  83. EP240703a: Kinder optical follow-up observations
  84. EP240703c: EP-WXT detection of an X-ray transient
  85. IPN triangulation of GRB 240627A
  86. The first three GRBs detected by SVOM: X-ray Upper Limits from EP-WXT
  87. EP240703b: EP-WXT detection of a fast X-ray transient
  88. Konus-Wind detection of GRB 240703A (a counterpart of EP240703a)
  89. EP240702a: Swift/XRT upper limit
  90. EP240703a: EP-WXT detection of a fast X-ray transient
  91. EP240702a: GSP optical upper limit
  92. Fermi GRB 240702A: Global MASTER-Net observations report
  93. EP240702a: EP-WXT detection of a fast X-ray transient
  94. GRB 240627A: CALET Gamma-Ray Burst Monitor detection
  95. Fermi trigger No 741448122: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S240629by: Coverage and upper limits from MAXI/GSC observations
  97. Fermi trigger No 741356809: Global MASTER-Net observations report
  98. Fermi GRB 240629A: Global MASTER-Net observations report
  99. Fermi trigger No 741296200: Global MASTER-Net observations report
  100. Fermi trigger No 741251380: Global MASTER-Net observations report

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