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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"

16141 results found.

  1. EP240913a/GRB 240913C: 1.6m Mephisto observations
  2. EP240918a: SVOM/VT upper limit
  3. EP240919a / GRB 240919A: REM optical and NIR upper limits
  4. EP240919a / GRB 240919A: KAIT optical upper limit
  5. EP240918b and EP240918c: Optical upper limits with Kinder observations
  6. EP240919a: Optical upper limit with Kinder observations
  7. GRB 240910A: radio detection with the VLA
  8. EP240918a: 1.6m Mephisto multi-band Optical Upper Limit
  9. EP240919a: NOT and Gemini optical observations
  10. EP240919a: GOTO optical upper limits
  11. EP240919a: JinShan optical upper limits
  12. EP240918a: JinShan optical upper limits
  13. EP240918a: YAHPT Optical Upper Limit
  14. EP240918a: Optical upper limits with Kinder observations
  15. EP240918a: GMG Optical Upper Limit
  16. GRB 240916A: NOT optical observation
  17. GRB 240825A: The nature of the afterglow motivates the search of the associated supernova
  18. GRB 240916A: Fermi GBM Observation
  19. GRB 240916A (AT 2024vlp / GOTO24fzn): VLT/X-shooter redshift
  20. GRB 240916A: Swift-XRT afterglow detection
  21. GRB 240916A: JinShan optical decay in one of the two GOTO candidates
  22. GRB 240916A: GOTO identification of two new optical sources within the GBM localisation region
  23. EP240913a/GRB 240913C: KAIT optical upper limit
  24. GRB 240910A: SVOM/VT optical observations
  25. EP240913a: NOT optical upper limits
  26. EP240913a: JinShan optical upper limits
  27. EP240913a: ESO-NTT optical observations
  28. GRB 240914A: ESO-NTT optical observations
  29. GRB 240905E: further NOT optical observations
  30. GRB 240911A: LCO optical observations
  31. GRB 240911A: JinShan optical upper limits on two Swift/XRT candidates
  32. GRB 240911A: GOTO optical limits on Swift/XRT candidates
  33. GRB 240912A: J-band observations with WINTER
  34. GRB 240912A: LCOGT detection and Legacy Surveys likely host galaxy
  35. GRB 240912A: NOT optical spectroscopy
  36. Fast X-ray Transient EP240801a: GMRT radio observations
  37. GRB 240912A: Swift detection of a burst with an optical counterpart
  38. GRB 240910A: NOT optical observations
  39. GRB 240911A : a likely weak GRB detected by SVOM/ECLAIRs
  40. GRB 240910A: Swift-XRT detection of GOTO24fvl/AT2024vfp
  41. GRB 240910A: JinShan optical observations
  42. GRB 240910A: GOTO candidate optical counterpart
  43. EP240908a: Optical afterglow confirmation
  44. GRB 240825A: 7DT Optical Upper Limit
  45. GRB 240905E: SVOM/VT optical observations
  46. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  47. EP240908a: Mondy and AbAO follow-up observations
  48. EP240908a: Updates on the WXT detection result around the trigger time
  49. EP240908a: optical afterglow candidate
  50. EP240908a: TRT optical upper limit
  51. GRB 240905B: GOTO optical upper limits
  52. GRB 240905E: GIT optical upper limit
  53. GRB 240905E: Gaoyazi/GOT optical upper limits
  54. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  55. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  56. GRB 240905E: AKO Optical Upper Limit
  57. GRB 240905E: SVOM/C-GFT optical upper limit
  58. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  59. GRB 240905E: NOT optical upper limits
  60. GRB 240905E: REM optical/NIR upper limits
  61. GRB 240905E: LCOGT Optical Upper Limit
  62. GRB 240905E: Swift/UVOT Upper Limits
  63. GRB 240905E: SAO RAS optical upper limit
  64. GRB 240825A: Montarrenti Observatory optical follow-up observations
  65. GRB 240905E: Nanshan/HMT optical upper limit
  66. GRB 240819A: Optical upper limits from TESS
  67. GRB 240825A: ATCA Detection of Radio Counterpart
  68. GRB 240825A: Magnitude Correction in SVOM/C-GFT Optical Observations
  69. GRB 240825A: MeerLICHT afterglow detection
  70. GRB 240828A: SAO RAS AS-500(2) optical observations
  71. GRB 240821A: VLT spectroscopic observations
  72. GRB 240825A: TSHAO Optical Upper Limit
  73. GRB240828B: REM optical/NIR upper limits
  74. GRB 240828B: AbAO optical upper limit
  75. GRB 240825A: SOAR observations
  76. GRB 240828B: Mephisto optical upper limit
  77. GRB 240828B: GRANDMA Optical Upper Limit
  78. GRB 240825A: MeerKAT detection
  79. GRB 240828B: GMG Optical Upper Limit
  80. GRB 240828A: KAIT continued optical observations
  81. GRB 240828B: GWAC-F50A optical upper limit
  82. GRB 240828B: SVOM/C-GFT optical upper limit
  83. GRB 240828B: SAO RAS optical upper limit
  84. GRB 240828B: KAIT optical upper limit
  85. GRB 240828A: SAO RAS optical observations
  86. GRB 240828A: KAIT Optical Afterglow Candidate
  87. GRB 240825A: SVOM/VT optical detection
  88. GRB 240825A: further SAO RAS optical observations
  89. GRB 240825A: iTelescope optical observations
  90. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  91. GRB 240825A: Upper limits from a neutrino search with IceCube
  92. GRB 240819A as a likely X-Ray Flash
  93. GRB 240821A: PRIME near-infrared observations
  94. GRB 240825A: VLA detection
  95. SVOM GRB 240821A: optical afterglow discovery
  96. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  97. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  98. GRB 240825A: ALMA detection
  99. GRB 240825A: SAO RAS optical observations
  100. GRB 240824A: GIT optical upper limit

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