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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"

19689 results found.

  1. GRB 241229A: SVOM detection of a long burst
  2. GRB241228B: GROWTH-India Telescope optical observations
  3. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  4. GRB 241228A: GROWTH-India telescope optical upper limit
  5. GRB 241228B: Swift ToO observations
  6. GRB 241228B: TRT optical counterpart confirmation
  7. GRB 241228A: Swift-XRT refined Analysis
  8. GRB 241228A: Swift/UVOT Upper Limits
  9. GRB 241228A: Enhanced Swift-XRT position
  10. GRB 241228A: Swift detection of a burst
  11. EP241223a: Mondy AZT-33IK optical observations
  12. GRB 241029A: LCO optical observation
  13. GRB 241223A: Swift-XRT observations
  14. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  15. GRB 241029A: AbAO AS-32 optical observations
  16. EP241223a
  17. EP241223a: EP-WXT detection of a fast X-ray transient
  18. GRB241113A: 7DT Optical upper limits
  19. GRB 241105A: JWST photometric observations of the host galaxy
  20. GRB 241223A: Swift ToO observations
  21. EP241217a: Liverpool Telescope optical upper limit
  22. EP241021a: VLA radio detection
  23. GRB 241218A: Mondy AZT-33IK optical upper limit
  24. EP241217a : Leavitt Observatory optical upper limit
  25. EP241217a: 1.6m Mephisto multi-band optical observations
  26. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  27. GRB 241218A: Swift/UVOT Upper Limits
  28. EP241217a: optical upper limit with the Liverpool Telescope
  29. GRB 241218A: NOT optical upper limits
  30. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  31. EP 241217a: NIR detection with P200/WIRC
  32. EP 241217a: Possible J-band detection with WINTER
  33. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  34. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  35. GRB 241217A / EP241217b: NOT optical upper limits
  36. GRB 241218A: REM optical upper limit
  37. GRB 241217A/EP241217b: REM optical/NIR upper limits
  38. EP241217a: REM optical/NIR upper limits
  39. GRB 241217a: Liverpool Telescope optical follow-up
  40. EP241217a: Liverpool Telescope optical follow-up
  41. EP241217a: NOT optical observations
  42. EP241217a: GROWTH-India Telescope optical observations
  43. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  44. EP241119a: 7DT Optical upper limits
  45. EP241217a: Xinglong optical follow-up observations
  46. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  47. GRB 241218A: LCOGT Optical Upper Limit
  48. GRB 241218A: Enhanced Swift-XRT position
  49. GRB 241217A: GMG Optical Upper Limit
  50. GRB 241218A: Swift detection of a burst
  51. GRB 241217A : SVOM/VT optical afterglow detection
  52. GRB 241217A: Swift-XRT afterglow detection
  53. GRB 241217A: LCO optical upper limit
  54. GRB 241217A: GRANDMA/TAROT optical upperlimits
  55. EP241217a: Swift-XRT Detection
  56. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  57. EP241217a: Kinder optical follow-up observations
  58. EP241217A: LCO optical observations
  59. EP241217a: Gemini-North detection of the likely optical counterpart
  60. EP241217a: EP detection of an X-ray transient
  61. EP241107a: VLA Radio Observation
  62. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  63. GRB 241215A: Mondy AZT-33IK optical observations
  64. GRB 241212A: Swift-XRT observations
  65. GRB 241215A: Nanshan/HMT optical upper limit
  66. GRB 241215A: Montarrenti Observatory optical upper limit
  67. GRB 241215A: GROWTH-India telescope optical upper limit
  68. GRB 241213B: Tiled Swift observations
  69. GRB 241213A: Swift/UVOT Upper Limits
  70. EP241208a: NOT optical upper limits
  71. GRB 241212A: Swift ToO observations
  72. GRB 241213A: LCOGT Optical Upper Limits
  73. EP 241208A : Detection of a long soft transient by SVOM/ECLAIRs
  74. EP241213a: EP detection of An X-ray Transient
  75. GRB 241213A: REM optical/NIR upper limits
  76. GRB 241213A: Enhanced Swift-XRT position
  77. GRB241212A: OHP/T193 optical observations
  78. GRB 241213A: SAO RAS optical upper limit
  79. GRB 241213A: Swift detection of a burst
  80. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  81. GRB 241209B: GRANDMA/TRT upper limit
  82. GRB 241212A: SVOM detection of a bright long burst
  83. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  84. GRB 241209D: REM optical/NIR upper limits
  85. GRB 241209B: Swift-XRT afterglow detection
  86. EP241208a: Optical upper limit with Kinder observations
  87. GRB 241209D: AstroSat CZTI detection
  88. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  89. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  90. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  91. GRB 241209D: COLIBRÍ detection of the afterglow
  92. GRB 241209A: COLIBRÍ Optical Upper Limit
  93. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  94. GRB 241209A: GRANDMA/TAROT upper limit
  95. GRB 241209B: Swift ToO observations
  96. GRB 241209A: REM optical/NIR observations
  97. GRB 241209D: Enhanced Swift-XRT position
  98. GRB 241209D: Swift detection of a burst
  99. GRB 241209A: Enhanced Swift-XRT position
  100. GRB 241114B: cubesat Avion detection

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