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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"

36166 results found.

  1. EP241217a : Leavitt Observatory optical upper limit
  2. GRB 241217A/EP241217b: tentative VLT spectroscopic redshift z=1.879
  3. GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
  4. GRB 241218A: Swift/UVOT Upper Limits
  5. GRB 241209B: EP-FXT afterglow detection
  6. Konus-Wind detection of GRB 241204A (short/hard)
  7. GRB 241218A: NOT optical upper limits
  8. GRB 241218A: Swift-BAT refined analysis
  9. GRB 241217A / EP241217B: GRANDMA/T1MPicduMidi optical upperlimits
  10. GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
  11. GRB 241217A / EP241217b: Nanshan/HMT optical upper limit
  12. GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
  13. GRB 241217A / EP241217b: NOT optical upper limits
  14. GRB 241218A: REM optical upper limit
  15. GRB 241217A/EP241217b: REM optical/NIR upper limits
  16. GRB 241218a: Liverpool Telescope optical follow-up
  17. GRB 241217a: Liverpool Telescope optical follow-up
  18. GRB 241218A: Swift-XRT refined Analysis
  19. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  20. GRB 241209A: ATCA radio follow-up observations
  21. EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
  22. GRB 241218A: LCOGT Optical Upper Limit
  23. GRB 241218A: Enhanced Swift-XRT position
  24. GRB 241217A: GMG Optical Upper Limit
  25. GRB 241218A: Swift detection of a burst
  26. GRB 241217A : SVOM/VT optical afterglow detection
  27. GRB 241217A: Swift-XRT afterglow detection
  28. GRB 241217A: LCO optical upper limit
  29. GRB 241217A: GRANDMA/TAROT optical upperlimits
  30. EP241217A: Non-detection from Fermi-GBM Observations
  31. GRB 241217A : SVOM/ECLAIRs,GRM,MXT detection of a long burst with a bright X-ray afterglow candidate
  32. GRB 241214A: GRBAlpha detection
  33. GRB 241213A (EP241213a): GRBAlpha detection
  34. GRB 241209D: GRBAlpha detection
  35. GRB 241213A: Swift-BAT refined analysis
  36. GRB 241214A: Swift/BAT-GUANO localization skymap of a burst
  37. Konus-Wind detection of GRB 241213A (EP 241213a)
  38. GRB 241215A: Mondy AZT-33IK optical observations
  39. GRB 241212A: Swift-XRT observations
  40. GRB 241214A: SVOM/GRM observation
  41. GRB 241215A: Nanshan/HMT optical upper limit
  42. GRB 241215A: Montarrenti Observatory optical upper limit
  43. GRB 241215A: GROWTH-India telescope optical upper limit
  44. GRB 241215A: A long GRB detected by INTEGRAL
  45. GRB 241213B: Swift-XRT observations
  46. GRB 241209D: CALET Gamma-Ray Burst Monitor detection
  47. GRB 241209B: SVOM/VT optical continuous fading
  48. GRB 241213A: SVOM/VT optical candidate
  49. GRB 241213B: Tiled Swift observations
  50. GRB 241213A: Swift/UVOT Upper Limits
  51. GRB 241213B: CALET Gamma-Ray Burst Monitor detection
  52. GRB 241213A: Swift-XRT refined Analysis
  53. GRB 241212A: Fermi GBM detection
  54. GRB 241212A: Swift ToO observations
  55. GRB 241213A: LCOGT Optical Upper Limits
  56. EP241213a/GRB241213a: Likely joint detection and INTEGRAL/SPI-ACS counterpart
  57. GRB 241213B: MAXI/GSC detection
  58. GRB 241213A: REM optical/NIR upper limits
  59. GRB 241213A: Enhanced Swift-XRT position
  60. GRB241212A: OHP/T193 optical observations
  61. GRB 241213A: SAO RAS optical upper limit
  62. Swift GRB 241213A: Global MASTER-Net observations report
  63. GRB 241213A: Swift detection of a burst
  64. GRB 241212A : SVOM/C-GFT optical upper limit at early phase
  65. GRB 241212A : SVOM/VT bright optical afterglow
  66. GRB 241212A: AstroSat CZTI detection
  67. GRB 241209B: GRANDMA/TRT upper limit
  68. GRB 241207A: TSHAO Zeiss-1000 optical observations
  69. GRB 241212A: SVOM detection of a bright long burst
  70. GRB 241212A: Fermi GBM Final Real-time Localization
  71. GRB 241209B: Mondy AZT-33IK and AbAO AS-32 optical observations
  72. GRB 241209A: Chandra X-ray Detection
  73. Konus-Wind detection of GRB 241209B
  74. GRB 241207A: EIRSAT-1 GMOD Detection
  75. GRB 241209A: Redshift of the likely host galaxy z = 0.784 from OSIRIS+/GTC
  76. GRB 241209B: GRBAlpha detection
  77. GRB 241206C: GRBAlpha detection
  78. GRB 241211A: Fermi GBM Final Real-time Localization
  79. GRB 241129A: Fermi GBM Observation
  80. GRB 241209B: Swift/BAT-GUANO localization skymap of a burst
  81. GRB 241209D: REM optical/NIR upper limits
  82. Konus-Wind detection of GRB 241209D
  83. GRB 241209B: Swift-XRT afterglow detection
  84. GRB 241209C: Fermi GBM Observation
  85. GRB 241209A: Swift-XRT refined Analysis
  86. Fermi Gamma-ray Burst Monitor trigger 755485387 / 241210044 is not a GRB
  87. GRB 241128A: CrAO ZTSh and Mondy AZT-33IK optical observations
  88. GRB 241209D: AstroSat CZTI detection
  89. GRB 241209A: EP-FXT follow-up observations
  90. GRB 241209B: SVOM/VT afterglow detection
  91. GRB 241207B: Fermi GBM Observation
  92. GRB 241209A: BOOTES-7 and 2.2m CAHA early optical upper limits
  93. GRB 241209D: Swift-XRT refined Analysis
  94. GRB 241209D: Fermi GBM Observation
  95. GRB 241209A: VLT/HAWK-I near-IR counterpart candidate
  96. GRB 241209D: COLIBRÍ detection of the afterglow
  97. GRB 241209A: COLIBRÍ Optical Upper Limit
  98. Fermi GRB 241209D: Global MASTER-Net observations report
  99. GRB 241209A: Fermi GBM Observation
  100. GRB 241209C: Swift/BAT-GUANO localization skymap of a burst

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