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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"

23707 results found.

  1. LIGO/Virgo/KAGRA S240601aj: Identification of a GW compact binary merger candidate
  2. Konus-Wind detection of GRB 240529A
  3. LIGO/Virgo/KAGRA S240531bp: Identification of a GW compact binary merger candidate
  4. GRB 240529A: T193/MISTRAL observations
  5. GRB 240529A: Redshift from GTC/OSIRIS+
  6. LIGO/Virgo/KAGRA S240530a: Identification of a GW compact binary merger candidate
  7. GRB 240529A: J-band detections with WINTER
  8. GRB 240529A: Skynet Optical Observations
  9. LXT 240528A: LEIA detection of a fast X-ray transient
  10. GRB 240529A: Swift-BAT refined analysis
  11. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  12. GRB240529A: BOOTES-6/DPRT optical detection
  13. GRB 240529A: NOT optical observations
  14. GRB 240529A: AstroSat CZTI detection
  15. GRB 240529A: GOTO optical afterglow detection
  16. GRB 240529A: Swift detection of a burst with an optical counterpart
  17. Swift GRB240529.12: Global MASTER-Net observations report
  18. Fermi GRB 240527A: Global MASTER-Net observations report
  19. LIGO/Virgo/KAGRA S240527fv: Identification of a GW compact binary merger candidate
  20. LAT GRB240527.59: Global MASTER-Net observations report
  21. LIGO/Virgo/KAGRA S240527en: Identification of a GW compact binary merger candidate
  22. Fermi GRB 240527B: Global MASTER-Net observations report
  23. GRB 240523A: Swift-BAT refined analysis
  24. Fermi trigger No 738348224: Global MASTER-Net observations report
  25. Fermi trigger No 738330463: Global MASTER-Net observations report
  26. GRB 240523A: Swift detection of a burst
  27. Fermi GBM Sub-Threshold Detection of GRB 240516B
  28. GRB 240513A: Swift-XRT afterglow detection
  29. Fermi trigger No 737996942: Global MASTER-Net observations report
  30. EP240518a: GSP optical upper limit
  31. GRB 240514B: VZLUSAT-2 detection
  32. GRB 240504A: VZLUSAT-2 detection
  33. GRB 240502A: VZLUSAT-2 detection
  34. GRB 240519A: GRBAlpha detection
  35. GRB 240516A: Swift/UVOT Upper Limits
  36. GRB 240519A: AstroSat CZTI detection
  37. Fermi trigger No 737788024: Global MASTER-Net observations report
  38. EP240518a: possibly identified with a flare star by EP-FXT
  39. EP240518a: EP-WXT detection of a new X-ray transient
  40. GRB 240516A: Swift-BAT refined analysis
  41. Fermi GRB 240517A: Global MASTER-Net observations report
  42. IPN triangulation of GRB 240514B (short)
  43. Konus-Wind detection of GRB 240513A
  44. GRB 240514E: A possible candidate BD-21 1074
  45. Fermi trigger No 737559855: Global MASTER-Net observations report
  46. GRB 240516A: Fermi GBM Observation
  47. GRB 240511A: Observations from GTC/OSIRIS+
  48. GRB 240516A: GOTO optical upper limit
  49. Fermi trigger No 737523389: Global MASTER-Net observations report
  50. GRB 240516A: Swift detection of a burst
  51. Swift GRB240516.15: Global MASTER-Net observations report
  52. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  53. Fermi trigger No 737476171: Global MASTER-Net observations report
  54. GRB 240514B: GOTO candidate optical counterpart
  55. MAXI GRB240514.78: Global MASTER-Net observations report
  56. GRB 240514E: MAXI/GSC detection of a probable afterglow
  57. GRB 240514B: GRBAlpha detection
  58. LIGO/Virgo/KAGRA S240515m: Identification of a GW compact binary merger candidate
  59. GRB 240513A: Swift-XRT observations
  60. LIGO/Virgo/KAGRA S240514x: Identification of a GW compact binary merger candidate
  61. GRB 240514D: AstroSat CZTI detection
  62. Fermi GRB 240514B: Global MASTER-Net observations report
  63. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  64. LAT GRB240513.31: Global MASTER-Net observations report
  65. LIGO/Virgo/KAGRA S240513ei: Identification of a GW compact binary merger candidate
  66. GRB 240511A: Swift-BAT refined analysis
  67. Fermi GRB 240513B: Global MASTER-Net observations report
  68. Fermi trigger No 737277727: Global MASTER-Net observations report
  69. GRB 240513A: AstroSat CZTI detection
  70. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  71. Fermi trigger No 737258655: Global MASTER-Net observations report
  72. GRB 240511A: J-band observations with WINTER
  73. Fermi trigger No 737247400: Global MASTER-Net observations report
  74. Fermi trigger No 737244199: Global MASTER-Net observations report
  75. Fermi trigger No 737218721: Global MASTER-Net observations report
  76. Fermi trigger No 737196587: Global MASTER-Net observations report
  77. Fermi trigger No 737168073: Global MASTER-Net observations report
  78. GRB 240511A : MITSuME Akeno optical upper limits
  79. GRB 240511A: Swift-XRT refined Analysis
  80. Fermi trigger No 737173236: Global MASTER-Net observations report
  81. Fermi GRB 240511A: Global MASTER-Net observations report
  82. Swift GRB 240511A: Global MASTER-Net observations report
  83. Fermi trigger No 737105243: Global MASTER-Net observations report
  84. Fermi trigger No 737152719: Global MASTER-Net observations report
  85. GRB 240511A: Swift detection of a burst
  86. Fermi trigger No 737102480: Global MASTER-Net observations report
  87. Fermi trigger No 737111207: Global MASTER-Net observations report
  88. LIGO/Virgo/KAGRA S240511i: Identification of a GW compact binary merger candidate
  89. Fermi trigger No 736967879: Global MASTER-Net observations report
  90. EP240506a: Xinglong optical upper limit
  91. EP240506a: Archival radio searching
  92. EP240506a: TRT optical upper limit
  93. EP240506a: BOOTES Network optical upper limit
  94. Fermi trigger No 736733320: Global MASTER-Net observations report
  95. EP240506a: Optical upper limit with Kinder observations
  96. IPN triangulation of GRB 240504A
  97. EP240506a: EP-WXT detection of a new fast X-ray transient
  98. LIGO/Virgo/KAGRA S240507p: Identification of a GW compact binary merger candidate
  99. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  100. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs

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