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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"

28118 results found.

  1. GRB 211225A/MAXI J0827-071: MAXI/GSC detection
  2. GRB 211106A: Third HST Observation
  3. Fermi trigger No 662010159: Global MASTER-Net observations report
  4. GRB 211223C: Swift-BAT refined analysis
  5. Fermi GBM Sub-Threshold Detection of GRB 211221A
  6. Fermi GBM Sub-Threshold Detection of GRB 211207A
  7. GRB 211221A: Swift-BAT refined analysis
  8. GRB 211223C: Swift detection of a burst
  9. GRB 211223A: GECAM detection
  10. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  11. GRB 211219B: AstroSat CZTI detection
  12. GRB 211219A: AstroSat CZTI detection
  13. GRB 211221A: Swift-XRT refined Analysis
  14. GRB 211218A: MITSuME Akeno optical upper limits
  15. GRB 211221A: MeerLICHT optical limits
  16. GRB 211221A: NOT optical limits
  17. GRB 211221A: Enhanced Swift-XRT position
  18. GRB 211221A: Swift detection of a burst
  19. IceCube-211216B: No significant detection in HAWC
  20. IceCube-211216A: No significant detection in HAWC
  21. GRB 211219A: Swift/BAT-GUANO detection outside the coded FOV
  22. GRB 211216A: Fermi GBM observation
  23. IceCube-211216B: No neutrino counterpart candidates in ANTARES search
  24. GRB 211218A, MAXI J0909-041: MAXI/GSC detection
  25. MAXI GRB211218.04: Global MASTER-Net observations report
  26. Fermi-LAT Gamma-ray Observations of IceCube-211216B
  27. Fermi-LAT Gamma-ray Observations of IceCube-211216A
  28. IceCube-211216A: Upper limits from a search for additional neutrino events in IceCube
  29. IceCube-211216A: No neutrino counterpart candidates in ANTARES search
  30. GRB 211217A: GECAM detection
  31. GRB 211216A: Swift/BAT-GUANO detection outside the coded FOV
  32. GRB 211216B: GECAM detection
  33. IceCube-211216A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  34. GRB 211211A: TNG NIR observations
  35. GRB 211216A: GECAM detection
  36. GRB 211216A: BALROG localization (Fermi Trigger 661329957 / GRB 211216282)
  37. GRB 211211A - Gemini K-band detection
  38. GRB 211211A: SAO RAS optical observations
  39. GRB 211211A: AbAO optical observations
  40. GRB 211211A: GMG upper limit
  41. Chandra observation of GW170817 at ~1575 days since merger (all epochs)
  42. GRB 211211A: redshift estimation and SPI-ACS/INTEGRAL detection
  43. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  44. GRB 211211A: HCT and GIT optical follow up observations
  45. IceCube-211208A: No neutrino counterpart detected with ANTARES
  46. GRB 211211A: Swift/UVOT detection
  47. GRB 211211B: GECAM detection
  48. GRB 211211A: Afterglow detection from CAFOS/2.2m CAHA
  49. GRB 211211A: MITSuME Akeno optical observation
  50. GRB 211211A: LCO Optical Observations
  51. GRB 211211A: Nanshan/NEXT optical observations
  52. GRB 211211A: Swift-XRT refined Analysis
  53. GRB 211211A: Fermi GBM observation
  54. GRB 211211A: Swift-BAT refined analysis
  55. GRB 211211A: Enhanced Swift-XRT position
  56. GRB 211207A: Swift/UVOT Detection
  57. GRB 211211A: Swift detection of a bright burst
  58. IceCube-211208A: No significant detection in HAWC
  59. AMON NuEm-211020A: No neutrino counterpart detected with ANTARES
  60. GRB 211130A: MeerLICHT identification of possible afterglow candidate
  61. IceCube-211208A: Upper limits from a search for additional neutrino events in IceCube
  62. Fermi-LAT Gamma-ray Observations of IceCube-211208A
  63. IceCube-211208A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  64. GRB 211207A: Swift-BAT refined analysis
  65. Chandra observation of GW170817 at ~1573 days since merger (Epoch 1 of 4)
  66. GRB 211207A: Swift-XRT refined Analysis
  67. GRB 211207A: Enhanced Swift-XRT position
  68. GRB 211207A: Swift detection of a burst with an optical counterpart
  69. GRB 211206A: AstroSat CZTI detection
  70. GRB 211206B: AstroSat CZTI detection
  71. GRB 211204C: AstroSat CZTI detection
  72. IPN triangulation of GRB 211204C
  73. GRB 211206A: Swift/BAT-GUANO detection outside the coded FOV
  74. GRB 211204C: Swift/BAT-GUANO detection outside the coded FOV
  75. GRB 211204C: GECAM detection
  76. GRB 211124A: Fermi GBM Observation
  77. Fermi GBM Upper limits for GRB 211203A
  78. GRB 211203A: Swift detection of a burst
  79. GRB 211201A: Swift/BAT-GUANO detection likely outside the coded FOV
  80. GRB 211106A: Second HST Observation
  81. GRB 211201A: Fermi GBM Final Real-time Localization
  82. IceCube-211125A: No significant detection in HAWC
  83. GRB 211130A: BALROG localization (Fermi Trigger 659978192 / GRB 211130636)
  84. GRB 211129A: Swift-BAT refined analysis
  85. GRB 211129A: Swift-XRT refined Analysis
  86. GRB 211129A: Swift/UVOT Upper Limits
  87. GRB 211106A: HST Observations
  88. GRB 211106A: Chandra Observations
  89. IceCube-Cascade 211128A: Upper limits from a search for additional neutrino events in IceCube
  90. IceCube-211125A: Upper limits from a search for additional neutrino events in IceCube
  91. GRB 211129A: Fermi GBM observation
  92. GRB 211129A: Nanshan/NEXT optical upper limit
  93. GRB 211129A: Enhanced Swift-XRT position
  94. IPN triangulation of GRB 211118A
  95. GRB 211129A: MITSuME Akeno optical upper limits
  96. GRB 211129A: Swift detection of a burst
  97. IceCube-211125A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  98. GRB 211023A: Xinglong 2.16m optical observations
  99. Fermi-LAT Gamma-ray Observations of IceCube-211125A
  100. GRB 211120548: Fermi GBM observation

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