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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"

21011 results found.

  1. GRB 240825A: SVOM/C-GFT optical observations
  2. GRB 240825A: Montarrenti Observatory optical observations
  3. GRB 240825A: MASTER optical counterpart observation
  4. GRB 240825A: LCO optical observations
  5. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  6. Fermi GRB 240825A: Global MASTER-Net observations report
  7. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  8. GRB 240824B: NOT optical upper limit
  9. Swift GRB 240825A: Global MASTER-Net observations report
  10. GRB 240825A: 1.6m Mephisto multi-band detection
  11. GRB 240825A: Skynet Optical Afterglow observations
  12. GRB 240825A: Nanshan/HMT optical afterglow observations
  13. GRB 240824B: Swift-XRT afterglow detection
  14. GRB 240824A: Swift-XRT observations
  15. GRB 240824B: Swift/BAT arcminute localization of a burst
  16. GRB 240824B: Swift ToO observations
  17. Fermi GRB 240824C: Global MASTER-Net observations report
  18. GRB 240824A: Swift/UVOT Upper Limits
  19. GRB 240821A: Swift/UVOT observations of the XRT sources.
  20. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  21. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  22. GRB 240824A: KAIT optical upper limit
  23. GRB 240824A: Skynet Optical Afterglow Discovery
  24. Swift GRB240824.04: Global MASTER-Net observations report
  25. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  26. GRB 240821A: Colibri Optical Upper Limit
  27. EP240820a: PRIME J-band Observations
  28. GRB 240821A: Swift-XRT observations
  29. GRB 240821A: REM optical/NIR upper limits
  30. GRB 240821A: LCO optical observations
  31. GRB 240821A: JinShan optical upper limits
  32. GRB 240809A: Mondy and AbAO Optical Observations
  33. GRB 240821A: SVOM/VT follow-up and optical upper limit
  34. Fermi GRB 240821A: Global MASTER-Net observations report
  35. Fermi trigger No 745964969: Global MASTER-Net observations report
  36. Fermi trigger No 745925274: Global MASTER-Net observations report
  37. GRB 240821A: Swift ToO observations
  38. Fermi trigger No 746019401: Global MASTER-Net observations report
  39. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  40. Fermi trigger No 745935375: Global MASTER-Net observations report
  41. Fermi GRB 240821B: Global MASTER-Net observations report
  42. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  43. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  44. Fermi trigger No 745866488: Global MASTER-Net observations report
  45. GRB 240819A: Swift-XRT observations
  46. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  47. EP240820a: TRT optical upper limit
  48. EP240820a: EP detection of a fast X-ray transient
  49. GRB 240819A: KAIT optical upper limit
  50. EP240816a: PRIME upper limits
  51. Fermi trigger No 745873283: Global MASTER-Net observations report
  52. Fermi trigger No 745871958: Global MASTER-Net observations report
  53. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  54. GRB 240819A: Swift ToO observations
  55. EP240816b: Liverpool Telescope optical follow-up observations
  56. Integral GRB240816.79: Global MASTER-Net observations report
  57. IceCube-240721A: AT2023qqp and AT2024pge likely unrelated
  58. GRB GRB 240809A: Osservatorio Astronomico "Nastro Verde" optical observations: detection of an optical counterpart
  59. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  60. Fermi trigger No 745501396: Global MASTER-Net observations report
  61. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  62. EP EP240816b: Global MASTER-Net observations report
  63. EP240816b: TRT optical upper limit
  64. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  65. Fermi GRB 240814A: Global MASTER-Net observations report
  66. Fermi GRB 240814C: Global MASTER-Net observations report
  67. Fermi trigger No 745306088: Global MASTER-Net observations report
  68. Fermi GRB 240814B: Global MASTER-Net observations report
  69. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  70. Fermi trigger No 745220784: Global MASTER-Net observations report
  71. GRB 240809A: ATA radio non-detection
  72. GRB 240809A : RAPAS follow-up observations
  73. GRB 240809A: VLA detection
  74. GRB 240809A: ALMA detection
  75. EP240807a: PRIME H-band upper limits
  76. GRB 240811A: Bassano Bresciano Observatory upper limit
  77. GRB 240811A: Swift/UVOT Upper Limits
  78. EP240801a: Assy-Turgen optical observations
  79. Fermi GRB 240810A: Global MASTER-Net observations report
  80. GRB 240811A: Upper limits with Mephisto
  81. Fermi trigger No 745057312: Global MASTER-Net observations report
  82. Swift GRB 240811A: Global MASTER-Net observations report
  83. GRB240809A: Liverpool Telescope optical follow-up observations
  84. GRB 240809A: REM detection of the optical afterglow
  85. GRB 240809A: Bassano Bresciano Observatory optical observations
  86. Fermi-LAT gamma-ray observations of IceCube-240808A
  87. GRB 240809A: KAIT optical observations
  88. GRB 240809A: GIT afterglow observations
  89. GRB 240809A: Swift/UVOT Detection
  90. GRB 240809A: Tentative redshift from NOT
  91. X-ray Transient EP240807a: PRIME near-infrared upper limits
  92. Swift GRB 240809A: Global MASTER-Net observations report
  93. GRB 240809A: JinShan optical observations
  94. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  95. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  96. EP240807a: STEP/T80S optical limits
  97. IceCube Alert 240808.27: Global MASTER-Net observations report
  98. EP EP240807a: Global MASTER-Net observations report
  99. EP EP240806a: Global MASTER-Net observations report
  100. GRB 240805A: ATCA Radio Upper Limits

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