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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19718 results found.

  1. LIGO/Virgo/KAGRA S240825ar: Upper limits from Swift/BAT-GUANO
  2. LIGO/Virgo/KAGRA S240807h: Upper limits from Swift/BAT-GUANO
  3. GRB 240825A: MeerLICHT afterglow detection
  4. GRB 240828A: SAO RAS AS-500(2) optical observations
  5. GRB 240825A: TSHAO Optical Upper Limit
  6. GRB240828B: REM optical/NIR upper limits
  7. GRB 240828B: AbAO optical upper limit
  8. GRB 240825A: SOAR observations
  9. GRB 240828B: Mephisto optical upper limit
  10. GRB 240828B: GRANDMA Optical Upper Limit
  11. LIGO/Virgo/KAGRA S240830gn: Identification of a GW compact binary merger candidate
  12. GRB 240828B: J-band upper limit from WINTER
  13. GRB 240828B: GMG Optical Upper Limit
  14. GRB 240828B: SVOM/C-GFT optical upper limit
  15. GRB 240828B: SAO RAS optical upper limit
  16. GRB 240828A: SAO RAS optical observations
  17. GRB 240828A: KAIT Optical Afterglow Candidate
  18. GRB 240825A: SVOM/VT optical detection
  19. GRB 240825A: further SAO RAS optical observations
  20. GRB 240825A: iTelescope optical observations
  21. GRB 240828B: Swift-XRT afterglow detection
  22. GRB 240828A: Tiled Swift observations
  23. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  24. GRB 240828B: Swift ToO observations
  25. GRB 240821A: PRIME near-infrared observations
  26. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  27. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  28. GRB 240825A: SAO RAS optical observations
  29. GRB 240824A: GIT optical upper limit
  30. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  31. GRB 240825A: GMG Continued Optical Observation on the Second Night
  32. GRB 240825A: PRIME near-infrared detection
  33. GRB 240825A: Fermi GBM Observation
  34. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  35. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  36. GRB 240825A: Swift/UVOT Detection
  37. GRB 240825A: REM detection of the optical/NIR afterglow
  38. GRB 240825A: Montarrenti Observatory optical observations
  39. GRB 240825A: Enhanced Swift-XRT position
  40. GRB 240825A: LCO optical observations
  41. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  42. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  43. GRB 240824B: NOT optical upper limit
  44. GRB 240825A: GMG Optical Observation
  45. GRB 240825A: 1.6m Mephisto multi-band detection
  46. GRB 240825A: AKO Optical Afterglow Detection
  47. GRB 240825A: Skynet Optical Afterglow observations
  48. GRB 240825A: Nanshan/HMT optical afterglow observations
  49. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  50. GRB 240824A: SVOM/C-GFT optical upper limit
  51. GRB 240824B: Swift-XRT afterglow detection
  52. GRB 240824B: Swift ToO observations
  53. GRB 240824A: Swift/UVOT Upper Limits
  54. GRB 240821A: Swift/UVOT observations of the XRT sources.
  55. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  56. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  57. GRB 240824A: Skynet Optical Afterglow Discovery
  58. GRB 240824A: Swift detection of a burst
  59. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  60. GRB 240821A: Colibri Optical Upper Limit
  61. EP240820a: PRIME J-band Observations
  62. GRB 240821A: REM optical/NIR upper limits
  63. GRB 240821A: LCO optical observations
  64. GRB 240821A: JinShan optical upper limits
  65. GRB 240809A: Mondy and AbAO Optical Observations
  66. GRB 240821A: GMG Optical Upper Limit
  67. Fermi trigger No 745964969: Global MASTER-Net observations report
  68. GRB 240821A: Swift ToO observations
  69. Fermi-GBM Observations of the reactivation of SGR 1E 1841-045 / Kes 73
  70. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  71. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  72. EP240820a: TRT optical upper limit
  73. EP240820a: EP detection of a fast X-ray transient
  74. EP240816a: PRIME upper limits
  75. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  76. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  77. GRB 240819A: Swift ToO observations
  78. EP240816b: Liverpool Telescope optical follow-up observations
  79. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  80. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  81. EP240816b: TRT optical upper limit
  82. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  83. Fermi GRB 240814B: Global MASTER-Net observations report
  84. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  85. EP240807a: PRIME H-band upper limits
  86. GRB 240812B: AstroSat CZTI detection of a long burst
  87. GRB 240811A: Bassano Bresciano Observatory upper limit
  88. GRB 240811A: Swift/UVOT Upper Limits
  89. EP240801a: Assy-Turgen optical observations
  90. GRB 240811A: LCOGT Optical Upper Limit
  91. GRB 240811A: Enhanced Swift-XRT position
  92. GRB 240811A: Upper limits with Mephisto
  93. GRB 240811A: Swift detection of a burst
  94. GRB 240809A: REM detection of the optical afterglow
  95. GRB 240809A: Bassano Bresciano Observatory optical observations
  96. Konus-Wind detection of GRB 240807A (a counterpart of EP240807a)
  97. GRB 240809A: GIT afterglow observations
  98. GRB 240809A: Swift/UVOT Detection
  99. IPN triangulation of GRB 240807A / EP 240807a
  100. X-ray Transient EP240807a: PRIME near-infrared upper limits

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