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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"

28302 results found.

  1. EP 241217a: Possible J-band detection with WINTER
  2. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  3. EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
  4. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  5. GRB 241217A / EP241217b: NOT optical upper limits
  6. GRB 241218A: REM optical upper limit
  7. GRB 241217A/EP241217b: REM optical/NIR upper limits
  8. EP241217a: REM optical/NIR upper limits
  9. GRB 241217a: Liverpool Telescope optical follow-up
  10. EP241217a: Liverpool Telescope optical follow-up
  11. GRB 241218A: Swift-XRT refined Analysis
  12. EP241217a: NOT optical observations
  13. EP241217a: GROWTH-India Telescope optical observations
  14. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  15. EP241119a: 7DT Optical upper limits
  16. EP241217a: Xinglong optical follow-up observations
  17. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  18. GRB 241218A: LCOGT Optical Upper Limit
  19. GRB 241218A: Enhanced Swift-XRT position
  20. GRB 241217A: GMG Optical Upper Limit
  21. GRB 241218A: Swift detection of a burst
  22. GRB 241217A : SVOM/VT optical afterglow detection
  23. GRB 241217A: Swift-XRT afterglow detection
  24. GRB 241217A: LCO optical upper limit
  25. GRB 241217A: GRANDMA/TAROT optical upperlimits
  26. EP241217a: Swift-XRT Detection
  27. EP241217A: Non-detection from Fermi-GBM Observations
  28. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  29. EP241217a: Kinder optical follow-up observations
  30. EP241217A: LCO optical observations
  31. EP241217a: Gemini-North detection of the likely optical counterpart
  32. EP241217a: EP detection of an X-ray transient
  33. EP241107a: VLA Radio Observation
  34. GRB 241213A: Swift-BAT refined analysis
  35. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  36. GRB 241215A: Mondy AZT-33IK optical observations
  37. GRB 241212A: Swift-XRT observations
  38. GRB 241215A: Nanshan/HMT optical upper limit
  39. GRB 241215A: Montarrenti Observatory optical upper limit
  40. GRB 241215A: GROWTH-India telescope optical upper limit
  41. GRB 241215A: A long GRB detected by INTEGRAL
  42. Integral GRB241215.58: Global MASTER-Net observations report
  43. GRB 241213B: Swift-XRT observations
  44. GRB 241213A: Swift/UVOT Upper Limits
  45. GRB 241213A: Swift-XRT refined Analysis
  46. GRB 241212A: Fermi GBM detection
  47. EP241208a: NOT optical upper limits
  48. GRB 241213A: LCOGT Optical Upper Limits
  49. GRB 241213B: MAXI/GSC detection
  50. EP241213a: EP detection of An X-ray Transient
  51. GRB 241213A: REM optical/NIR upper limits
  52. GRB 241213A: Enhanced Swift-XRT position
  53. GRB241212A: OHP/T193 optical observations
  54. GRB 241213A: SAO RAS optical upper limit
  55. LIGO/Virgo/KAGRA S241210fu: Updated Sky localization
  56. GRB 241213A: Swift detection of a burst
  57. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  58. GRB 241212A: AstroSat CZTI detection
  59. GRB 241209B: GRANDMA/TRT upper limit
  60. GRB 241207A: TSHAO Zeiss-1000 optical observations
  61. GRB 241212A: SVOM detection of a bright long burst
  62. GRB 241207A: EIRSAT-1 GMOD Detection
  63. LIGO/Virgo/KAGRA S241210cw: Updated Sky localization
  64. LIGO/Virgo/KAGRA S241210d: Updated Sky localization and EM Bright Classification
  65. GRB 241129A: Fermi GBM Observation
  66. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  67. GRB 241209D: REM optical/NIR upper limits
  68. GRB 241209B: Swift-XRT afterglow detection
  69. GRB 241209C: Fermi GBM Observation
  70. GRB 241209A: Swift-XRT refined Analysis
  71. LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
  72. EP241208a: Optical upper limit with Kinder observations
  73. GRB 241209B: SVOM/VT afterglow detection
  74. LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
  75. LIGO/Virgo/KAGRA S241210d: Identification of a GW compact binary merger candidate
  76. GRB 241207B: Fermi GBM Observation
  77. GRB 241209D: Swift-XRT refined Analysis
  78. GRB 241209D: Fermi GBM Observation
  79. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  80. GRB 241209D: COLIBRÍ detection of the afterglow
  81. GRB 241209A: COLIBRÍ Optical Upper Limit
  82. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst
  83. GRB 241209A: GRANDMA/TAROT upper limit
  84. GRB 241209A: REM optical/NIR observations
  85. GRB 241209D: Enhanced Swift-XRT position
  86. GRB 241209D: Swift detection of a burst
  87. GRB 241209A: Enhanced Swift-XRT position
  88. GRB 241114B: cubesat Avion detection
  89. GRB 241209A: VLT optical observations
  90. GRB 241209A: GOTO optical upper limits
  91. GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
  92. EP241208a: EP detection of a fast X-ray transient
  93. GRB 241209A: Swift detection of a short burst
  94. Fermi GRB 241207B: Global MASTER-Net observations report
  95. GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
  96. GRB 241206A: DDOTI Upper Limit on the Afterglow
  97. AT2024adec: X-ray Upper Limits from EP-FXT Observation
  98. GRB 241207C: MAXI/GSC detection
  99. EP241206a: EP detection of a fast X-ray transient
  100. GRB 241206A: Fermi GBM observation

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