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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"

21985 results found.

  1. Fermi trigger No 720498201: Global MASTER-Net observations report
  2. Fermi trigger No 720415645: Global MASTER-Net observations report
  3. Fermi GRB 231030B: Global MASTER-Net observations report
  4. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  5. Fermi GRB 231030A: Global MASTER-Net observations report
  6. LIGO/Virgo/KAGRA S231029ai: Global MASTER-Net observations report
  7. LIGO/Virgo/KAGRA S231029k: Global MASTER-Net observations report
  8. Fermi trigger No 720224759: Global MASTER-Net observations report
  9. Swift GRB 231028A: Global MASTER-Net observations report
  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. GRB 231017A: Swift/UVOT Upper Limit
  30. GRB 230911C: ATCA detection of possible radio counterpart
  31. GRB 231017A: GOTO optical upper limits
  32. IC231004A: Classification of AT2023uqf/ZTF23abidzvf as a rapidly-evolving supernova with CSM interaction
  33. GRB 231017A: Swift-XRT observations
  34. GRB 231017A: Swift ToO observations
  35. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  36. Fermi-LAT gamma-ray observations of IceCube-231014A
  37. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  38. (correction) Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field
  39. Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field.
  40. IceCube-231004A: One Candidate Counterpart from the Zwicky Transient Facility
  41. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  42. Fermi-LAT gamma-ray observations of IceCube-231004A
  43. transient AT2023sva: radio observations with AMI-LA
  44. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  45. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  46. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  47. AT2023sva / GRB230916B: GIT observations of the afterglow
  48. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  49. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  51. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  52. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  53. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  54. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  55. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  56. LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP
  57. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  58. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  59. transient AT2023sva: imaging and spectroscopic observations from MISTRAL at Observatoire de Haute-Provence
  60. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  61. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  62. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  63. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  64. AT 2023sva: NOT observations of the ZTF candidate afterglow
  65. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  66. GRB 230812B: Radio observations with the uGMRT
  67. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  68. Swift GRB230916.18: Global MASTER-Net observations report
  69. Fermi trigger No 716572242: Global MASTER-Net observations report
  70. Fermi trigger No 716544961: Global MASTER-Net observations report
  71. Fermi-LAT gamma-ray observations of IceCube-230914A
  72. GRB 230915A: Swift/BAT-GUANO detection of a burst
  73. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  74. Swift GRB230916.19: Global MASTER-Net observations report
  75. Swift GRB230916.18: Global MASTER-Net observations report
  76. Swift GRB230916.13: Global MASTER-Net observations report
  77. Swift GRB230916.12: Global MASTER-Net observations report
  78. Swift GRB230916.11: Global MASTER-Net observations report
  79. GRB 230906A: optical counterpart
  80. GRB 230911A: Swift-XRT afterglow detection
  81. Fermi trigger No 716449174: Global MASTER-Net observations report
  82. IceCube Alert 230914.22: Global MASTER-Net observations report
  83. Fermi trigger No 716419312: Global MASTER-Net observations report
  84. Swift GRB230913.70: Global MASTER-Net observations report
  85. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  86. Swift GRB230913.70: Global MASTER-Net observations report
  87. GRB 230911A: Swift ToO observations
  88. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  89. Fermi GRB 230913A: Global MASTER-Net observations report
  90. GRB 230911A: GOTO optical counterpart candidate
  91. GRB 230906A: Chandra detection of the X-ray afterglow
  92. Swift GRB 230911C: Global MASTER-Net observations report
  93. GRB 230911C: Swift/UVOT Upper Limits
  94. Fermi trigger No 716145795: Global MASTER-Net observations report
  95. GRB 230911C: GOTO optical upper limits
  96. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  97. Fermi GRB 230911B: Global MASTER-Net observations report
  98. GRB 230903A: TESS observations of optical emission
  99. GRB 230906A: Swift/UVOT Upper Limits
  100. GRB 230818A: radio observation with the VLA

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