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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

20840 results found.

  1. GRB 240825A: SVOM/VT optical detection
  2. GRB 240828A: Swift-XRT afterglow detection
  3. GRB 240825A: further SAO RAS optical observations
  4. GRB 240825A: iTelescope optical observations
  5. GRB 240828B: Swift-XRT afterglow detection
  6. GRB 240829A: Swift detection of a burst
  7. GRB 240828A: AstroSat CZTI detection of a long burst
  8. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  9. GRB 240819A as a likely X-Ray Flash
  10. GRB 240821A: PRIME near-infrared observations
  11. GRB 240828B : Detection of a possible very soft X-ray transient by SVOM/ECLAIRs
  12. GRB 240821A: the second and third EP-FXT follow-up observations and afterglow candidates
  13. GRB 240825A: SAO RAS optical observations
  14. GRB 240824A: GIT optical upper limit
  15. GRB 240819A: Swift afterglow confirmation
  16. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  17. GRB 240825A: GMG Continued Optical Observation on the Second Night
  18. GRB 240825A: PRIME near-infrared detection
  19. GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
  20. GRB 240825A: AstroSat CZTI detection of the long bright burst
  21. SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
  22. GRB 240825A: Swift/UVOT Detection
  23. GRB 240825A: REM detection of the optical/NIR afterglow
  24. GRB 240825A: Montarrenti Observatory optical observations
  25. GRB 240825A: Enhanced Swift-XRT position
  26. GRB 240825A: MASTER optical counterpart observation
  27. GRB 240825A: LCO optical observations
  28. SGR 1E 1841-045 / Kes 73 (Trigger 1249878): Osservatorio Atronomico Nastro Verde optical upper limit
  29. GRB 240824B: Fermi GBM Observation
  30. SGR 1E 1841-045 / Kes 73 (Trigger 1249653) - Osservatorio Astronomico Nastro Verde upper limit
  31. GRB 240824B: NOT optical upper limit
  32. GRB 240825A: GMG Optical Observation
  33. GRB 240825A: 1.6m Mephisto multi-band detection
  34. GRB 240825A: AKO Optical Afterglow Detection
  35. GRB 240825A: Skynet Optical Afterglow observations
  36. GRB 240825A: Nanshan/HMT optical afterglow observations
  37. GRB 240825A: Swift detection of a burst with a bright optical counterpart
  38. GRB 240824A: SVOM/C-GFT optical upper limit
  39. GRB 240824B: Swift-XRT afterglow detection
  40. GRB 240824A: Swift-XRT observations
  41. LIGO/Virgo/KAGRA S240825ar: Identification of a GW compact binary merger candidate
  42. GRB 240824B: Swift/BAT arcminute localization of a burst
  43. GRB 240824A: Swift/UVOT Upper Limits
  44. GRB 240821A: Swift/UVOT observations of the XRT sources.
  45. GRB240824A: GRANDMA/TAROT-TCA Upper Limit
  46. SGR 1E 1841-045 / Kes 73: Leavitt Observatory optical upper limit
  47. GRB 240824A: Skynet Optical Afterglow Discovery
  48. GRB 240824A: Swift detection of a burst
  49. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  50. GRB 240821A: Colibri Optical Upper Limit
  51. EP240820a: PRIME J-band Observations
  52. GRB 240821A: Swift-XRT observations
  53. GRB 240821A: REM optical/NIR upper limits
  54. GRB 240821A: LCO optical observations
  55. GRB 240821A: JinShan optical upper limits
  56. GRB 240809A: Mondy and AbAO Optical Observations
  57. GRB 240821A: GMG Optical Upper Limit
  58. EP240801a: Keck/LRIS spectroscopic redshift confirmation
  59. GRB 240821A: GRANDMA/LesMakes-T60 Upper Limit
  60. Trigger 1249878: Swift detection of another burst from SGR 1E 1841-045 / Kes 73
  61. GRB 240821A : a likely short GRB detected by SVOM/ECLAIRs
  62. GRB 240819A: Swift-XRT observations
  63. GRB 240819A: JinShan optical upper limits on one Swift/XRT source
  64. EP240820a: TRT optical upper limit
  65. EP240820a: EP detection of a fast X-ray transient
  66. EP240816a: PRIME upper limits
  67. Trigger 1249653: Swift detection of SGR 1E 1841-045 / Kes 73
  68. GRB 240819A : an X-ray transient detected by SVOM/ECLAIRs
  69. GRB 240819A: TRT optical upper limits on the Swift/XRT and EP/FXT sources
  70. GRB 240819A: X-ray follow-up observation with EP-FXT
  71. EP240816b: Liverpool Telescope optical follow-up observations
  72. GRB 240805B: Osservatorio Astronomico Nastro Verde upper limit
  73. EP240816a: EP detection of a fast X-ray transient and follow-up observation
  74. EP240816b: TRT optical upper limit
  75. EP240816b: EP-WXT detection and EP-FXT follow-up observation of a fast X-ray transient
  76. EP240802a: Kinder optical, SWIFT-UVOT, and SWIFT-XRT upper limits 6 days after the WXT detection
  77. Konus-Wind detection of GRB 240810A
  78. LIGO/Virgo/KAGRA S240813d: Identification of a GW compact binary merger candidate
  79. LIGO/Virgo/KAGRA S240813c: Identification of a GW compact binary merger candidate
  80. GRB 240809A: ATA radio non-detection
  81. GRB 240809A : RAPAS follow-up observations
  82. IPN triangulation of GRB 240810A (short)
  83. EP240807a: PRIME H-band upper limits
  84. GRB 240812B: AstroSat CZTI detection of a long burst
  85. GRB 240811A: Bassano Bresciano Observatory upper limit
  86. GRB 240811A: Swift/UVOT Upper Limits
  87. EP240801a: Assy-Turgen optical observations
  88. GRB 240811A: LCOGT Optical Upper Limit
  89. GRB 240811A: Enhanced Swift-XRT position
  90. GRB 240811A: Upper limits with Mephisto
  91. GRB 240811A: Swift detection of a burst
  92. GRB 240809A: REM detection of the optical afterglow
  93. GRB 240809A: Bassano Bresciano Observatory optical observations
  94. GRB 240808A: AstroSat CZTI detection
  95. GRB 240809A: GIT afterglow observations
  96. GRB 240809A: Swift/UVOT Detection
  97. IPN triangulation of GRB 240807A / EP 240807a
  98. LIGO/Virgo/KAGRA S240807h: Updated Sky localization and EM Bright Classification
  99. X-ray Transient EP240807a: PRIME near-infrared upper limits
  100. GRB 240809A: JinShan optical observations

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