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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

12407 results found.

  1. GRB 240606B: Swift-XRT afterglow detection
  2. Swift GRB240606.15: Global MASTER-Net observations report
  3. Fermi GRB 240604A: Global MASTER-Net observations report
  4. Fermi GRB 240605A: Global MASTER-Net observations report
  5. Fermi GRB 240605C: Global MASTER-Net observations report
  6. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  7. Fermi GRB 240603C: Global MASTER-Net observations report
  8. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  9. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  10. Swift Trigger 1232465: consistent with noise
  11. Fermi GRB 240602A: Global MASTER-Net observations report
  12. Swift Trigger 1232465 is not a GRB
  13. LXT 240528A: GSP optical upper limit
  14. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  16. GRB 240529A: Swift/UVOT Detection
  17. GRB 240527B: Swift-XRT afterglow detection
  18. Swift GRB240529.12: Global MASTER-Net observations report
  19. Fermi GRB 240527A: Global MASTER-Net observations report
  20. LAT GRB240527.59: Global MASTER-Net observations report
  21. Fermi GRB 240527B: Global MASTER-Net observations report
  22. Fermi trigger No 738348224: Global MASTER-Net observations report
  23. Fermi trigger No 738330463: Global MASTER-Net observations report
  24. GRB 240523A: Swift detection of a burst
  25. Fermi trigger No 737996942: Global MASTER-Net observations report
  26. EP240518a: GSP optical upper limit
  27. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  28. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  29. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  30. IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
  31. GRB 240516A: Swift/UVOT Upper Limits
  32. Fermi trigger No 737788024: Global MASTER-Net observations report
  33. Fermi GRB 240517A: Global MASTER-Net observations report
  34. GRB 240516A ATCA radio observations
  35. GRB 240516A: Swift-XRT refined Analysis
  36. Fermi trigger No 737559855: Global MASTER-Net observations report
  37. GRB 240516A: GOTO optical upper limit
  38. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  39. Fermi trigger No 737523389: Global MASTER-Net observations report
  40. GRB 240516A: Swift detection of a burst
  41. Swift GRB240516.15: Global MASTER-Net observations report
  42. Fermi trigger No 737476171: Global MASTER-Net observations report
  43. MAXI GRB240514.78: Global MASTER-Net observations report
  44. GRB 240514E: MAXI/GSC detection of a probable afterglow
  45. LIGO/Virgo/KAGRA S240422ed: Las Cumbres Observatory Follow-up Observations of the Localization Region
  46. GRB 240513A: Swift-XRT observations
  47. Fermi GRB 240514B: Global MASTER-Net observations report
  48. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  49. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  50. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  51. LAT GRB240513.31: Global MASTER-Net observations report
  52. Fermi GRB 240513B: Global MASTER-Net observations report
  53. Fermi trigger No 737277727: Global MASTER-Net observations report
  54. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  55. Fermi trigger No 737258655: Global MASTER-Net observations report
  56. GRB 240511A: J-band observations with WINTER
  57. Fermi trigger No 737247400: Global MASTER-Net observations report
  58. Fermi trigger No 737244199: Global MASTER-Net observations report
  59. Fermi trigger No 737218721: Global MASTER-Net observations report
  60. Fermi trigger No 737196587: Global MASTER-Net observations report
  61. Fermi trigger No 737168073: Global MASTER-Net observations report
  62. GRB 240511A : MITSuME Akeno optical upper limits
  63. Fermi trigger No 737173236: Global MASTER-Net observations report
  64. Fermi GRB 240511A: Global MASTER-Net observations report
  65. Swift GRB 240511A: Global MASTER-Net observations report
  66. Fermi trigger No 737105243: Global MASTER-Net observations report
  67. Fermi trigger No 737152719: Global MASTER-Net observations report
  68. GRB 240511A: Swift detection of a burst
  69. Fermi trigger No 737102480: Global MASTER-Net observations report
  70. Fermi trigger No 737111207: Global MASTER-Net observations report
  71. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  72. LIGO/Virgo/KAGRA S240422ed: P200 observations of AT2024hit
  73. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  74. Fermi trigger No 736967879: Global MASTER-Net observations report
  75. EP240506a: Xinglong optical upper limit
  76. EP240506a: CrAO ZTSH optical upper limit
  77. EP240506a: TRT optical upper limit
  78. EP240506a: BOOTES Network optical upper limit
  79. LIGO/Virgo/KAGRA S240422ed: Upper limits from a two-week IceCube neutrino search
  80. Fermi trigger No 736733320: Global MASTER-Net observations report
  81. EP240506a: Optical upper limit with Kinder observations
  82. GRB 240502A: 1.3m DFOT Optical upper limit
  83. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  84. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  85. Fermi trigger No 736564880: Global MASTER-Net observations report
  86. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  87. Fermi trigger No 736461232: Global MASTER-Net observations report
  88. Fermi GRB 240504A: Global MASTER-Net observations report
  89. Fermi trigger No 736472503: Global MASTER-Net observations report
  90. Fermi trigger No 736387941: Global MASTER-Net observations report
  91. GRB 240502A: GOTO optical upper limit
  92. Fermi trigger No 736379109: Global MASTER-Net observations report
  93. GRB 240415A 1.3m DFOT Optical upper limit
  94. Fermi GRB 240502B: Global MASTER-Net observations report
  95. Fermi GRB 240502A: Global MASTER-Net observations report
  96. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  97. Integral GRB240502.23: Global MASTER-Net observations report
  98. LIGO/Virgo/KAGRA S240422ed: Host redshifts of AT2024hfq, AT2024hfu, and AT2024hmo from DBSP
  99. Fermi GRB 240501A: Global MASTER-Net observations report
  100. Fermi trigger No 736197684: Global MASTER-Net observations report

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