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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"

23695 results found.

  1. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  2. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  3. GRB 241218A: REM optical upper limit
  4. GRB 241217A/EP241217b: REM optical/NIR upper limits
  5. EP241217a: REM optical/NIR upper limits
  6. GRB 241218A: Swift-XRT refined Analysis
  7. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  8. EP241217a: Xinglong optical follow-up observations
  9. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  10. GRB 241217A: GMG Optical Upper Limit
  11. GRB 241218A: Swift detection of a burst
  12. GRB 241217A : SVOM/VT optical afterglow detection
  13. GRB 241217A: Swift-XRT afterglow detection
  14. EP241217a: Swift-XRT Detection
  15. EP241217A: Non-detection from Fermi-GBM Observations
  16. EP241217a: Kinder optical follow-up observations
  17. GRB 241214A: GRBAlpha detection
  18. GRB 241213A (EP241213a): GRBAlpha detection
  19. GRB 241209D: GRBAlpha detection
  20. EP241217A: LCO optical observations
  21. The EP-WXT trigger 01709129023 is likely a flaring star
  22. EP241107a: VLA Radio Observation
  23. GRB 241213A: Swift-BAT refined analysis
  24. Konus-Wind detection of GRB 241213A (EP 241213a)
  25. GRB 241212A: Swift-XRT observations
  26. The EP-WXT trigger 01709128948 is likely a flaring star
  27. GRB 241215A: Montarrenti Observatory optical upper limit
  28. The EP-WXT trigger 01709128921 is likely a flaring star
  29. GRB 241213B: Swift-XRT observations
  30. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  31. GRB 241209B: SVOM/VT optical continuous fading
  32. GRB 241213A: SVOM/VT optical candidate
  33. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  34. EP241208a: NOT optical upper limits
  35. GRB 241213B: MAXI/GSC detection
  36. GRB 241213A: REM optical/NIR upper limits
  37. GRB 241213A: SAO RAS optical upper limit
  38. GRB 241212A : SVOM/VT bright optical afterglow
  39. GRB 241212A: AstroSat CZTI detection
  40. GRB 241209B: GRANDMA/TRT upper limit
  41. GRB 241207A: TSHAO Zeiss-1000 optical observations
  42. GRB 241212A: SVOM detection of a bright long burst
  43. Konus-Wind detection of GRB 241209B
  44. GRB 241207A: EIRSAT-1 GMOD Detection
  45. GRB 241209B: GRBAlpha detection
  46. GRB 241206C: GRBAlpha detection
  47. GRB 241209D: REM optical/NIR upper limits
  48. Konus-Wind detection of GRB 241209D
  49. GRB 241209B: Swift-XRT afterglow detection
  50. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  51. EP241208a: Optical upper limit with Kinder observations
  52. GRB 241209D: AstroSat CZTI detection
  53. GRB 241209B: SVOM/VT afterglow detection
  54. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  55. GRB 241209D: Swift-XRT refined Analysis
  56. GRB 241209D: Fermi GBM Observation
  57. GRB 241209D: COLIBRÍ detection of the afterglow
  58. GRB 241209A: COLIBRÍ Optical Upper Limit
  59. GRB 241209A: GRANDMA/TAROT upper limit
  60. GRB 241209B: BOOTES-5 optical upper limit
  61. Swift GRB 241209D: Global MASTER-Net observations report
  62. LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
  63. GRB 241209A: REM optical/NIR observations
  64. GRB 241209D: Swift detection of a burst
  65. GRB 241114B: cubesat Avion detection
  66. GRB 241209A: VLT optical observations
  67. GRB 241209A: GOTO optical upper limits
  68. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  69. GRB 241209A: Swift detection of a short burst
  70. GRB 241206A: DDOTI Upper Limit on the Afterglow
  71. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  72. EP241206a: BOOTES Global Network optical limits
  73. GRB 241207C: MAXI/GSC detection
  74. GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
  75. EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
  76. GRB 241206A: Fermi GBM Final Real-time Localization
  77. GRB 241204A: COLIBRÍ Optical Upper Limit
  78. EP241202b: KAIT optical upper limit
  79. LIGO/Virgo/KAGRA S241125n: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
  80. GRB 241204A: DDOTI Upper Limits on the Afterglow
  81. GRB 241130A: CALET Gamma-Ray Burst Monitor detection
  82. GRB 241201A: GRBAlpha detection
  83. EP241202b: Upper limits from Fermi-GBM Observations
  84. EP241202b: Kinder optical counterpart candidate
  85. Konus-Wind detection of GRB 241130A
  86. EP241201a: BOOTES-5 optical upper limit
  87. EP241201a: NOT optical observations
  88. IPN triangulation of GRB 241130A
  89. GRB 241130A: EIRSAT-1 GMOD Detection
  90. EP241201a: Kinder optical counterpart candidate
  91. Konus-Wind detection of GRB 241114B
  92. LIGO/Virgo/KAGRA S241125n: GRANDMA Optical Upper Limits
  93. LIGO/Virgo/KAGRA S241130be: Identification of a GW compact binary merger candidate
  94. LIGO/Virgo/KAGRA S241130n: Identification of a GW compact binary merger candidate
  95. GRB 241128A: Swift-BAT refined analysis
  96. GRB 241127A: Swift-BAT refined analysis
  97. GRB 241128A: GRANDMA and Kilonova-Catcher Optical Afterglow Detections and Upperlimits
  98. Fermi-LAT gamma-ray observations of IceCube-241127A
  99. EP241126a: SVOM/VT observations
  100. LIGO/Virgo/KAGRA S241129aa: Identification of a GW compact binary merger candidate

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