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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"

21945 results found.

  1. GRB 241229B: SVOM/GRM observation
  2. LIGO/Virgo/KAGRA S241231bg: Identification of a GW compact binary merger candidate
  3. EP241217A: J band upper limit by SYSU 80cm telescope
  4. LIGO/Virgo/KAGRA S241230ev: Identification of a GW compact binary merger candidate
  5. GRB 241229B: SAO RAS optical upper limit
  6. GRB 241228B: SAO RAS optical observations
  7. GRB 241229A: SAO RAS optical observations
  8. Konus-Wind detection of GRB 241228A
  9. EP240702a: 7DT Optical upper limits
  10. GRB 240606B: 7DT Optical upper limits
  11. LIGO/Virgo/KAGRA S241230bd: Identification of a GW compact binary merger candidate
  12. LIGO/Virgo/KAGRA S241225c: Updated Sky localization and EM Bright Classification
  13. GRB241229B: UVOT upper limits
  14. GRB 241228B: Swift-XRT afterglow detection
  15. GRB 241229B: Fermi GBM Observation
  16. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  17. GRB 241228A: Mondy optical afterglow observations
  18. GRB 241229A: GOTO optical upper limits
  19. GRB 241228B: VLT/X-shooter redshift of z = 2.674
  20. GRB 241228A: NOT optical upper limits
  21. GRB 241228B: LCO optical observation
  22. GRB 241228A: Swift-BAT refined analysis
  23. GRB 241228B: Swift/BAT-GUANO localization skymap of a burst
  24. GRB241228B: GROWTH-India Telescope optical observations
  25. GRB 241226A: Swift/BAT-GUANO localization skymap of a burst
  26. GRB 241228A: GROWTH-India telescope optical upper limit
  27. GRB 241228B: TRT optical counterpart confirmation
  28. GRB 241228A: Swift/UVOT Upper Limits
  29. GRB 241228B: GOTO possible optical counterpart candidate
  30. GRB 241228A: Enhanced Swift-XRT position
  31. GRB 241228A: Swift detection of a burst
  32. GRB 241223A: GRBAlpha detection
  33. GRB 241212A: VZLUSAT-2 detection
  34. EP241223a: Mondy AZT-33IK optical observations
  35. GRB 241029A: LCO optical observation
  36. GRB 241223A: Swift-XRT observations
  37. LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
  38. GRB 241029A: AbAO AS-32 optical observations
  39. GRB 241223A: Fermi GBM Detection
  40. LIGO/Virgo/KAGRA S241225c: Identification of a GW compact binary merger candidate
  41. EP241223a
  42. EP241223a: EP-WXT detection of a fast X-ray transient
  43. EP241113a: Non-detection in Radio Follow-up Observations with eMERLIN
  44. GRB241113A: 7DT Optical upper limits
  45. GRB 241223A: GOTO optical observations summary
  46. GRB 241105A: JWST photometric observations of the host galaxy
  47. EP241217a: e-MERLIN radio observations
  48. The EP-WXT trigger 01709129287 is likely a flaring star
  49. EP241217a: Liverpool Telescope optical upper limit
  50. EP241021a: VLA radio detection
  51. GRB 241218A: Mondy AZT-33IK optical upper limit
  52. EP241217a : Leavitt Observatory optical upper limit
  53. EP241217a: 1.6m Mephisto multi-band optical observations
  54. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  55. GRB 241218A: Swift/UVOT Upper Limits
  56. EP241217a: optical upper limit with the Liverpool Telescope
  57. GRB 241218A: NOT optical upper limits
  58. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  59. EP 241217a: NIR detection with P200/WIRC
  60. EP 241217a: Possible J-band detection with WINTER
  61. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  62. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  63. GRB 241217A / EP241217b: NOT optical upper limits
  64. GRB 241218A: REM optical upper limit
  65. GRB 241217A/EP241217b: REM optical/NIR upper limits
  66. EP241217a: REM optical/NIR upper limits
  67. GRB 241217a: Liverpool Telescope optical follow-up
  68. EP241217a: Liverpool Telescope optical follow-up
  69. EP241217a: NOT optical observations
  70. EP241217a: GROWTH-India Telescope optical observations
  71. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  72. EP241119a: 7DT Optical upper limits
  73. EP241217a: Xinglong optical follow-up observations
  74. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  75. GRB 241218A: LCOGT Optical Upper Limit
  76. GRB 241218A: Enhanced Swift-XRT position
  77. GRB 241217A: GMG Optical Upper Limit
  78. GRB 241218A: Swift detection of a burst
  79. GRB 241217A : SVOM/VT optical afterglow detection
  80. GRB 241217A: Swift-XRT afterglow detection
  81. GRB 241217A: LCO optical upper limit
  82. GRB 241217A: GRANDMA/TAROT optical upperlimits
  83. EP241217a: Swift-XRT Detection
  84. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  85. EP241217a: Kinder optical follow-up observations
  86. GRB 241214A: GRBAlpha detection
  87. GRB 241213A (EP241213a): GRBAlpha detection
  88. GRB 241209D: GRBAlpha detection
  89. EP241217A: LCO optical observations
  90. EP241217a: Gemini-North detection of the likely optical counterpart
  91. EP241217a: EP detection of an X-ray transient
  92. EP241107a: VLA Radio Observation
  93. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  94. Konus-Wind detection of GRB 241213A (EP 241213a)
  95. GRB 241215A: Mondy AZT-33IK optical observations
  96. GRB 241212A: Swift-XRT observations
  97. GRB 241215A: Nanshan/HMT optical upper limit
  98. GRB 241215A: Montarrenti Observatory optical upper limit
  99. GRB 241215A: GROWTH-India telescope optical upper limit
  100. Integral GRB241215.58: Global MASTER-Net observations report

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