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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"

21048 results found.

  1. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  2. Fermi GRB 240814A: Global MASTER-Net observations report
  3. Fermi GRB 240814C: Global MASTER-Net observations report
  4. Fermi trigger No 745306088: Global MASTER-Net observations report
  5. Fermi GRB 240814B: Global MASTER-Net observations report
  6. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  7. Fermi trigger No 745220784: Global MASTER-Net observations report
  8. GRB 240809A: ATA radio non-detection
  9. GRB 240809A : RAPAS follow-up observations
  10. GRB 240809A: VLA detection
  11. GRB 240809A: ALMA detection
  12. EP240807a: PRIME H-band upper limits
  13. GRB 240811A: Bassano Bresciano Observatory upper limit
  14. GRB 240811A: Swift/UVOT Upper Limits
  15. EP240801a: Assy-Turgen optical observations
  16. Fermi GRB 240810A: Global MASTER-Net observations report
  17. GRB 240811A: Upper limits with Mephisto
  18. Fermi trigger No 745057312: Global MASTER-Net observations report
  19. Swift GRB 240811A: Global MASTER-Net observations report
  20. GRB240809A: Liverpool Telescope optical follow-up observations
  21. GRB 240809A: REM detection of the optical afterglow
  22. GRB 240809A: Bassano Bresciano Observatory optical observations
  23. Fermi-LAT gamma-ray observations of IceCube-240808A
  24. GRB 240809A: KAIT optical observations
  25. GRB 240809A: GIT afterglow observations
  26. GRB 240809A: Swift/UVOT Detection
  27. GRB 240809A: Tentative redshift from NOT
  28. X-ray Transient EP240807a: PRIME near-infrared upper limits
  29. Swift GRB 240809A: Global MASTER-Net observations report
  30. GRB 240809A: JinShan optical observations
  31. GRB 240809A: Skynet & Photon Ranch Optical Afterglow Observations
  32. EP-WXT trigger 01709018832: SVOM/C-GFT observations of the star flare
  33. EP240807a: STEP/T80S optical limits
  34. IceCube Alert 240808.27: Global MASTER-Net observations report
  35. EP EP240807a: Global MASTER-Net observations report
  36. EP EP240806a: Global MASTER-Net observations report
  37. GRB 240805A: ATCA Radio Upper Limits
  38. Fermi trigger No 744761058: Global MASTER-Net observations report
  39. EP-WXT trigger 01709018832: KAIT optical observations of the star flare
  40. EP240806A: Liverpool Telescope optical follow-up observations
  41. EP240807a: EP-WXT detection of a fast X-ray transient
  42. EP240806a: Gemini North-GMOS spectroscopic redshift of z = 2.818
  43. GRB 240805B: GIT optical upper limit
  44. EP240806a: KAIT optical observations
  45. Fermi trigger No 744629911: Global MASTER-Net observations report
  46. EP240804a (GRB 240804B): NOT optical observations
  47. EP240806a: LCOGT optical counterpart detection
  48. GRB 240805B Bassano Bresciano Observatory upper limit
  49. GRB 240805B: JinShan optical afterglow detection
  50. GRB 240805B: AbAO, CrAO, and Terskol optical upper limits
  51. EP 240806A: LCO optical observations
  52. EP240806a: GSP optical counterpart detection
  53. EP240806a: EP-WXT detection of a fast X-ray transient
  54. GRB 240805B: Optical detection with 1.6m Mephisto
  55. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  56. Fermi trigger No 744544656: Global MASTER-Net observations report
  57. GRB 240805B: Swift/UVOT Upper Limits
  58. GRB 240805A: Swift/UVOT Upper Limits
  59. Swift GRB 240805B: Global MASTER-Net observations report
  60. GRB 240805B: JinShan optical upper limits
  61. Fermi GRB 240805A: Global MASTER-Net observations report
  62. Swift GRB 240805A: Global MASTER-Net observations report
  63. EP240804a: GSP detects optical candidate counterpart
  64. EP240801a: Continued optical observations at ZTSh (CraO)
  65. EP240804a: VLT/X-shooter spectroscopic redshift
  66. EP240804a: LCOGT optical counterpart detection
  67. EP240804a: NOT optical counterpart detection
  68. EP240804a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  69. GRB 240805A: Swift detection of a burst
  70. Fermi GRB 240804A: Global MASTER-Net observations report
  71. EP240802a: Montarrenti Observatory optical upper limit
  72. Fermi trigger No 744459130: Global MASTER-Net observations report
  73. EP240801a: Osservatorio Astronomico Nastro Verde upper limit
  74. EP240802A: Bassano Bresciano Observatory upper limit
  75. GRB 240802A: SVOM/GRM observation
  76. EP240802a: Time coincidence with GRB 240802A and optical upper limits with Kinder observations
  77. Fermi trigger No 744278264: Global MASTER-Net observations report
  78. EP240802a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  79. EP240801a: further SAO RAS optical observations
  80. EP240801a: optical observations at CrAO and AbAO
  81. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  82. EP240801a: Leavitt Observatory optical observations
  83. EP240801a: GTC spectroscopy and absorption redshift
  84. EP240801a: SAO RAS optical observations
  85. EP240801a: JinShan optical observations
  86. EP240801a: NOT optical observations
  87. EP240801a: follow-up observation with LCOGT
  88. EP240801a: GSP follow-up observations of the candidate counterpart
  89. Fermi trigger No 744204856: Global MASTER-Net observations report
  90. EP240801a: Kinder follow-up observations of the candidate counterpart
  91. EP240708a: Kinder follow-up observations of the candidate counterpart (duplicate submission of GCN 37002)
  92. EP240801a: KAIT optical counterpart observations
  93. EP240801a: TRT optical counterpart detection
  94. EP240801a: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  95. Fermi GRB 240801A: Global MASTER-Net observations report
  96. Fermi trigger No 744128417: Global MASTER-Net observations report
  97. Fermi trigger No 744083370: Global MASTER-Net observations report
  98. GRB 240730A: Osservatorio Astronomico Nastro Verde upper limit
  99. Fermi GRB 240730B: Global MASTER-Net observations report
  100. Swift GRB 240730A: Global MASTER-Net observations report

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