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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.

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

21935 results found.

  1. LIGO/Virgo/KAGRA S241230bd: Identification of a GW compact binary merger candidate
  2. LIGO/Virgo/KAGRA S241225c: Updated Sky localization and EM Bright Classification
  3. GRB241229B: UVOT upper limits
  4. GRB 241228B: Swift-XRT afterglow detection
  5. GRB 241229B: Fermi GBM Observation
  6. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  7. GRB 241228A: Mondy optical afterglow observations
  8. GRB 241229A: GOTO optical upper limits
  9. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  10. GRB 241228A: NOT optical upper limits
  11. GRB 241228B: LCO optical observation
  12. GRB 241228A: Swift-BAT refined analysis
  13. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  14. GRB241228B: GROWTH-India Telescope optical observations
  15. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  16. GRB 241228A: GROWTH-India telescope optical upper limit
  17. GRB 241228B: TRT optical counterpart confirmation
  18. GRB 241228A: Swift/UVOT Upper Limits
  19. GRB 241228B: GOTO possible optical counterpart candidate
  20. GRB 241228A: Enhanced Swift-XRT position
  21. GRB 241228A: Swift detection of a burst
  22. GRB 241223A: GRBAlpha detection
  23. GRB 241212A: VZLUSAT-2 detection
  24. EP241223a: Mondy AZT-33IK optical observations
  25. GRB 241029A: LCO optical observation
  26. GRB 241223A: Swift-XRT observations
  27. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  28. GRB 241029A: AbAO AS-32 optical observations
  29. GRB 241223A: Fermi GBM Detection
  30. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  31. EP241223a
  32. EP241223a: EP-WXT detection of a fast X-ray transient
  33. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  34. GRB241113A: 7DT Optical upper limits
  35. GRB 241223A: GOTO optical observations summary
  36. GRB 241105A: JWST photometric observations of the host galaxy
  37. EP241217a: e-MERLIN radio observations
  38. The EP-WXT trigger 01709129287 is likely a flaring star
  39. EP241217a: Liverpool Telescope optical upper limit
  40. EP241021a: VLA radio detection
  41. GRB 241218A: Mondy AZT-33IK optical upper limit
  42. EP241217a : Leavitt Observatory optical upper limit
  43. EP241217a: 1.6m Mephisto multi-band optical observations
  44. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  45. GRB 241218A: Swift/UVOT Upper Limits
  46. EP241217a: optical upper limit with the Liverpool Telescope
  47. GRB 241218A: NOT optical upper limits
  48. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  49. EP 241217a: NIR detection with P200/WIRC
  50. EP 241217a: Possible J-band detection with WINTER
  51. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  52. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  53. GRB 241217A / EP241217b: NOT optical upper limits
  54. GRB 241218A: REM optical upper limit
  55. GRB 241217A/EP241217b: REM optical/NIR upper limits
  56. EP241217a: REM optical/NIR upper limits
  57. GRB 241217a: Liverpool Telescope optical follow-up
  58. EP241217a: Liverpool Telescope optical follow-up
  59. EP241217a: NOT optical observations
  60. EP241217a: GROWTH-India Telescope optical observations
  61. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  62. EP241119a: 7DT Optical upper limits
  63. EP241217a: Xinglong optical follow-up observations
  64. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  65. GRB 241218A: LCOGT Optical Upper Limit
  66. GRB 241218A: Enhanced Swift-XRT position
  67. GRB 241217A: GMG Optical Upper Limit
  68. GRB 241218A: Swift detection of a burst
  69. GRB 241217A : SVOM/VT optical afterglow detection
  70. GRB 241217A: Swift-XRT afterglow detection
  71. GRB 241217A: LCO optical upper limit
  72. GRB 241217A: GRANDMA/TAROT optical upperlimits
  73. EP241217a: Swift-XRT Detection
  74. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  75. EP241217a: Kinder optical follow-up observations
  76. GRB 241214A: GRBAlpha detection
  77. GRB 241213A (EP241213a): GRBAlpha detection
  78. GRB 241209D: GRBAlpha detection
  79. EP241217A: LCO optical observations
  80. EP241217a: Gemini-North detection of the likely optical counterpart
  81. EP241217a: EP detection of an X-ray transient
  82. EP241107a: VLA Radio Observation
  83. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  84. Konus-Wind detection of GRB 241213A (EP 241213a)
  85. GRB 241215A: Mondy AZT-33IK optical observations
  86. GRB 241212A: Swift-XRT observations
  87. GRB 241215A: Nanshan/HMT optical upper limit
  88. GRB 241215A: Montarrenti Observatory optical upper limit
  89. GRB 241215A: GROWTH-India telescope optical upper limit
  90. Integral GRB241215.58: Global MASTER-Net observations report
  91. GRB 241213A: Swift/UVOT Upper Limits
  92. EP241208a: NOT optical upper limits
  93. GRB 241213A: LCOGT Optical Upper Limits
  94. EP241213a: EP detection of An X-ray Transient
  95. GRB 241213A: REM optical/NIR upper limits
  96. GRB 241213A: Enhanced Swift-XRT position
  97. GRB241212A: OHP/T193 optical observations
  98. GRB 241213A: SAO RAS optical upper limit
  99. GRB 241213A: Swift detection of a burst
  100. GRB 241212A : SVOM/C-GFT optical upper limit at early phase

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