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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"

21089 results found.

  1. GRB 240529A: MASTER prompt OT detection
  2. GRB 240529A: continued SAO RAS optical observations
  3. Fermi GRB 240602A: Global MASTER-Net observations report
  4. GRB 240529A: OSN optical detection
  5. GRB 240529A: further SAO RAS optical observations
  6. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  7. LXT 240528A: GSP optical upper limit
  8. GRB 240529A: 1.3m DFOT Optical observations
  9. GRB 240529A : Mondy optical observations
  10. GRB 240529A: SAO RAS optical observations
  11. GRB 240529A: optical photometry from Konkoly
  12. GRB 240529A: T193/MISTRAL observations
  13. GRB 240529A: AKO Optical Afterglow Detection
  14. GRB 240529A: J-band detections with WINTER
  15. GRB 240529A: Skynet Optical Observations
  16. LXT 240528A: LEIA detection of a fast X-ray transient
  17. LIGO/Virgo S240527fv: GRANDMA/FRAM-Auger Optical Observations
  18. GRB 240529A: Swift/UVOT Detection
  19. GRB 240529A: NOT optical observations
  20. GRB 240529A: GOTO optical afterglow detection
  21. GRB 240527B: Swift-XRT afterglow detection
  22. Swift GRB240529.12: Global MASTER-Net observations report
  23. Fermi GRB 240527A: Global MASTER-Net observations report
  24. LAT GRB240527.59: Global MASTER-Net observations report
  25. Fermi GRB 240527B: Global MASTER-Net observations report
  26. Fermi trigger No 738348224: Global MASTER-Net observations report
  27. Fermi trigger No 738330463: Global MASTER-Net observations report
  28. GRB 240513A: Swift-XRT afterglow detection
  29. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  30. Fermi trigger No 737996942: Global MASTER-Net observations report
  31. EP240518a: GSP optical upper limit
  32. GRB 240516A: Swift/UVOT Upper Limits
  33. Fermi trigger No 737788024: Global MASTER-Net observations report
  34. EP240518a: EP-WXT detection of a new X-ray transient
  35. Fermi GRB 240517A: Global MASTER-Net observations report
  36. GRB 240516A ATCA radio observations
  37. GRB 240513A: Swift ToO observations
  38. GRB 240514E: A possible candidate BD-21 1074
  39. Fermi trigger No 737559855: Global MASTER-Net observations report
  40. GRB 240511A: Observations from GTC/OSIRIS+
  41. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  42. Fermi trigger No 737523389: Global MASTER-Net observations report
  43. Swift GRB240516.15: Global MASTER-Net observations report
  44. Fermi trigger No 737476171: Global MASTER-Net observations report
  45. GRB 240511A: radio detection of afterglow candidate
  46. GRB 240514B: GOTO candidate optical counterpart
  47. MAXI GRB240514.78: Global MASTER-Net observations report
  48. LIGO/Virgo/KAGRA S240422ed: Las Cumbres Observatory Follow-up Observations of the Localization Region
  49. GRB 240513A: Swift-XRT observations
  50. Fermi GRB 240514B: Global MASTER-Net observations report
  51. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  52. GRB 240513A: Tiled Swift observations
  53. LAT GRB240513.31: Global MASTER-Net observations report
  54. Fermi GRB 240513B: Global MASTER-Net observations report
  55. Fermi trigger No 737277727: Global MASTER-Net observations report
  56. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  57. Fermi trigger No 737258655: Global MASTER-Net observations report
  58. GRB 240511A: J-band observations with WINTER
  59. Fermi trigger No 737247400: Global MASTER-Net observations report
  60. Fermi trigger No 737244199: Global MASTER-Net observations report
  61. Fermi trigger No 737218721: Global MASTER-Net observations report
  62. Fermi trigger No 737196587: Global MASTER-Net observations report
  63. Fermi trigger No 737168073: Global MASTER-Net observations report
  64. GRB 240511A: optical afterglow detection from the NOT
  65. Fermi trigger No 737173236: Global MASTER-Net observations report
  66. Fermi GRB 240511A: Global MASTER-Net observations report
  67. Swift GRB 240511A: Global MASTER-Net observations report
  68. Fermi trigger No 737105243: Global MASTER-Net observations report
  69. Fermi trigger No 737152719: Global MASTER-Net observations report
  70. Fermi trigger No 737102480: Global MASTER-Net observations report
  71. Fermi trigger No 737111207: Global MASTER-Net observations report
  72. LIGO/Virgo/KAGRA S240422ed: GMOS-S photometry of J-GEM24a
  73. LIGO/Virgo/KAGRA S240422ed: P200 observations of AT2024hit
  74. LIGO/Virgo/KAGRA S240422ed: Candidates from the latest GW-MMADS DECam Observations
  75. Fermi trigger No 736967879: Global MASTER-Net observations report
  76. EP240506a: CrAO ZTSH optical upper limit
  77. EP240506a: Archival radio searching
  78. EP240506a: TRT optical upper limit
  79. Fermi trigger No 736733320: Global MASTER-Net observations report
  80. EP240506a: Optical upper limit with Kinder observations
  81. EP240506a: EP-WXT detection of a new fast X-ray transient
  82. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  83. LIGO/Virgo/KAGRA S240422ed: Swope Follow-up of AT2024hfr and AT2024hfs
  84. Fermi trigger No 736564880: Global MASTER-Net observations report
  85. IceCube-240424A: GRANDMA Optical Upper Limit of Fermi J2151.3+0220
  86. GRB 240502C: Zeiss-1000 at Koshka observatory observations of GOTO optical counterpart candidates
  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. GW170817: VLA observations at ~5.5 yrs since merger
  91. Fermi trigger No 736387941: Global MASTER-Net observations report
  92. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  93. GRB 240502A: GOTO optical upper limit
  94. Fermi trigger No 736379109: Global MASTER-Net observations report
  95. GRB 240502C: GOTO possible optical counterpart candidates
  96. Fermi GRB 240502B: Global MASTER-Net observations report
  97. Fermi GRB 240502A: Global MASTER-Net observations report
  98. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  99. Integral GRB240502.23: Global MASTER-Net observations report
  100. LIGO/Virgo/KAGRA S240422ed: Host redshifts of AT2024hfq, AT2024hfu, and AT2024hmo from DBSP

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