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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"

39364 results found.

  1. GRB 231015A: Glowbug gamma-ray detection
  2. GRB 231017A: LCOGT Optical Upper Limits
  3. GRB231017A: GROWTH-India upper limits on the optical afterglow
  4. GRB 231015A: AstroSat CZTI detection
  5. GRB 231018A: Fermi GBM Detection
  6. GRB 231017A: Fermi GBM Detection
  7. GRB 231017A: Swift-XRT observations
  8. GRB 231012B may not be a GRB
  9. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  10. GRB 231018A: Fermi GBM Final Real-time Localization
  11. GRB 231017A: Swift ToO observations
  12. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  13. GRB231017A: Fermi GBM Final Localization
  14. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  15. (correction) Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field
  16. Discovery of an optical transient with strong flaring activity: a new blazar candidate in the Messier 31 field.
  17. IceCube-231014A - IceCube observation of a high-energy neutrino candidate track-like event
  18. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  19. GRB 231012A: Fermi GBM Final Real-time Localization
  20. GRB 231012A: Fermi GBM Final Real-time Localization
  21. GRB 231004A: Glowbug gamma-ray detection
  22. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  23. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  24. Fermi-LAT gamma-ray observations of IceCube-231004A
  25. GRB 231004A: Fermi GBM Final Real-time Localization
  26. GRB 231003A is not a GRB
  27. GRB 231003A: Fermi GBM Final Real-time Localization
  28. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  29. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  30. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  31. GRB 230827B: 10.4m GTC spectroscopic redshift
  32. GRB 230930A: Fermi GBM Final Real-time Localization
  33. AT2023sva / GRB230916B: GIT observations of the afterglow
  34. transient AT2023sva: A Binary Driven Hypernova with a possible associated supernova
  35. Konus-Wind detection of GRB 230919A
  36. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  37. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  38. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  39. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  40. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  41. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  42. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  43. GRB 230921A: Fermi GBM Final Real-time Localization
  44. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  45. IPN triangulation of GRB 230919A (short)
  46. LIGO/Virgo/KAGRA S230904n: Classification of the candidate AT2023rkw with DBSP
  47. GRB 230919A: Fermi GBM Observation
  48. Fermi GBM Statement for Trigger 716527670/230916144
  49. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  50. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  51. GRB 230919A: AstroSat CZTI detection
  52. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  53. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  54. GRB 230919A: Fermi GBM Final Real-time Localization
  55. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  56. GRB 230918B: Fermi GBM Final Real-time Localization
  57. GRB 230918A (short): Glowbug gamma-ray detection
  58. GRB 230916B: Glowbug gamma-ray detection
  59. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  60. GRB 230915A: Fermi GBM observation
  61. GRB 230812B: Radio observations with the uGMRT
  62. GRB 230918A: Fermi GBM Final Real-time Localization
  63. GRB 230917A: AstroSat CZTI detection
  64. GRB 230915B: Glowbug gamma-ray detection
  65. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  66. GRB 230911A: Fermi GBM Observation
  67. Swift GRB230916.18: Global MASTER-Net observations report
  68. Fermi trigger No 716572242: Global MASTER-Net observations report
  69. Fermi trigger No 716544961: Global MASTER-Net observations report
  70. GRB 230915A: Swift/BAT-GUANO detection of a burst
  71. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  72. GRB 230911D: GRBAlpha detection
  73. Swift GRB230916.19: Global MASTER-Net observations report
  74. Swift GRB230916.18: Global MASTER-Net observations report
  75. Swift GRB230916.13: Global MASTER-Net observations report
  76. Swift GRB230916.12: Global MASTER-Net observations report
  77. Swift GRB230916.11: Global MASTER-Net observations report
  78. Swift Trigger 1192233 is not a GRB
  79. GRB 230906A: optical counterpart
  80. GRB 230911A: Swift-XRT afterglow detection
  81. Fermi trigger No 716449174: Global MASTER-Net observations report
  82. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  83. IceCube Alert 230914.22: Global MASTER-Net observations report
  84. Fermi trigger No 716419312: Global MASTER-Net observations report
  85. GRB 230913A: Glowbug gamma-ray detection
  86. GRB 230812B: Bad Time Intervals for Fermi GBM data
  87. IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event
  88. Swift GRB230913.70: Global MASTER-Net observations report
  89. GRB 230913A: Fermi GBM Observation
  90. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  91. Swift Trigger 1191904 is not a GRB
  92. Swift GRB230913.70: Global MASTER-Net observations report
  93. GRB 230911A: Swift ToO observations
  94. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  95. Fermi GRB 230913A: Global MASTER-Net observations report
  96. GRB 230911A: GOTO optical counterpart candidate
  97. GRB 230913A: Fermi GBM Final Real-time Localization
  98. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  99. GRB 230911D: NuSTAR Detection of Prompt Emission
  100. GRB 230911B: AstroSat CZTI detection

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