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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"

22208 results found.

  1. Fermi trigger No 720415645: Global MASTER-Net observations report
  2. Fermi GRB 231030B: Global MASTER-Net observations report
  3. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  4. Fermi GRB 231030A: Global MASTER-Net observations report
  5. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S231029k: Global MASTER-Net observations report
  7. Fermi trigger No 720224759: Global MASTER-Net observations report
  8. Swift GRB 231028A: Global MASTER-Net observations report
  9. GRB 231028A: Swift detection of a burst
  10. IceCube Alert 231027.18: Global MASTER-Net observations report
  11. LIGO/Virgo/KAGRA S231025t: Global MASTER-Net observations report
  12. LIGO/Virgo/KAGRA S231025a: Global MASTER-Net observations report
  13. IC231004A: GRANDMA observations of AT2023uqf/ZTF23abidzvf candidate
  14. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  15. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  16. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  17. GRB 231024A: GOTO optical counterpart candidate
  18. Fermi trigger No 719846439: Global MASTER-Net observations report
  19. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  20. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  21. LIGO/Virgo/KAGRA S231021az: Coverage and upper limits from MAXI/GSC observations
  22. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  23. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  24. Fermi GRB 231020A: Global MASTER-Net observations report
  25. LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
  26. GRB 231017A: 1.3m DFOT Optical upper limit
  27. IceCube-231004A: Upper limits from Fermi-GBM Observations
  28. Fermi GRB 231019A: Global MASTER-Net observations report
  29. Konus-Wind detection of GRB 231018A
  30. GRB 231017A: Swift/UVOT Upper Limit
  31. GRB 230911C: ATCA detection of possible radio counterpart
  32. GRB 231017A: GOTO optical upper limits
  33. IC231004A: Classification of AT2023uqf/ZTF23abidzvf as a rapidly-evolving supernova with CSM interaction
  34. GRB 231017A: Swift-XRT observations
  35. GRB 231017A: Swift ToO observations
  36. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  37. Fermi-LAT gamma-ray observations of IceCube-231014A
  38. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  39. (correction) Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field
  40. Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field.
  41. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  42. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  43. Fermi-LAT gamma-ray observations of IceCube-231004A
  44. transient AT2023sva: radio observations with AMI-LA
  45. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  47. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  48. AT2023sva / GRB230916B: GIT observations of the afterglow
  49. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  50. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  52. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  53. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  54. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  55. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  56. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  57. LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP
  58. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  59. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  60. transient AT2023sva: imaging and spectroscopic observations from MISTRAL at Observatoire de Haute-Provence
  61. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  62. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  63. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  64. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  65. AT 2023sva: NOT observations of the ZTF candidate afterglow
  66. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  67. GRB 230812B: Radio observations with the uGMRT
  68. Swift Triggers 1192480, 1192481, 1192482 and 1192483 are not astrophysical events
  69. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  70. Swift GRB230916.18: Global MASTER-Net observations report
  71. Fermi trigger No 716572242: Global MASTER-Net observations report
  72. Fermi trigger No 716544961: Global MASTER-Net observations report
  73. Fermi-LAT gamma-ray observations of IceCube-230914A
  74. GRB 230915A: Swift/BAT-GUANO detection of a burst
  75. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  76. Swift GRB230916.19: Global MASTER-Net observations report
  77. Swift GRB230916.18: Global MASTER-Net observations report
  78. Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events
  79. Swift GRB230916.13: Global MASTER-Net observations report
  80. Swift GRB230916.12: Global MASTER-Net observations report
  81. Swift GRB230916.11: Global MASTER-Net observations report
  82. GRB 230906A: optical counterpart
  83. GRB 230911A: Swift-XRT afterglow detection
  84. Fermi trigger No 716449174: Global MASTER-Net observations report
  85. IceCube Alert 230914.22: Global MASTER-Net observations report
  86. Fermi trigger No 716419312: Global MASTER-Net observations report
  87. Swift GRB230913.70: Global MASTER-Net observations report
  88. Swift GRB230913.70: Global MASTER-Net observations report
  89. GRB 230911A: Swift ToO observations
  90. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  91. Fermi GRB 230913A: Global MASTER-Net observations report
  92. GRB 230911A: GOTO optical counterpart candidate
  93. GRB 230906A: Chandra detection of the X-ray afterglow
  94. Swift GRB 230911C: Global MASTER-Net observations report
  95. GRB 230911C: Swift/UVOT Upper Limits
  96. Fermi trigger No 716145795: Global MASTER-Net observations report
  97. GRB 230911C: GOTO optical upper limits
  98. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  99. Konus-Wind detection of GRB 230811D
  100. Fermi GRB 230911B: Global MASTER-Net observations report

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