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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

2722 results found.

  1. IPN triangulation of GRB 220624A
  2. GRB 220623A: BOOTES-5/JGT optical afterglow detection
  3. Fermi trigger No 677377371: Global MASTER-Net observations report
  4. Fermi GRB 220620A: Global MASTER-Net observations report
  5. GRB 220619A: AstroSat CZTI detection
  6. Fermi GRB 220617A: Global MASTER-Net observations report
  7. Fermi trigger No 676909037: Global MASTER-Net observations report
  8. MAXI GRB220607.31: Global MASTER-Net observations report
  9. MAXI GRB220607.41: Global MASTER-Net observations report
  10. Fermi trigger No 675992935: Global MASTER-Net observations report
  11. IPN triangulation of GRB 220528A (short)
  12. Fermi GRB 220530A: Global MASTER-Net observations report
  13. GRB 220528B: Swift/BAT-GUANO detection outside the coded FOV
  14. Fermi trigger No 675411172: Global MASTER-Net observations report
  15. IPN triangulation of GRB 220524B
  16. IPN triangulation of GRB 220522B
  17. GRB 220521A: classification and detection by SPI-ACS/INTEGRAL
  18. Fermi GRB 220518B: Global MASTER-Net observations report
  19. GRB 220518A: Swift/UVOT Detection
  20. GRB 220514A: MITSuME Akeno optical observation
  21. IceCube-220513A: No Candidate Counterparts from the Zwicky Transient Facility
  22. IceCube Alert 220513.97: Global MASTER-Net observations report
  23. Fermi GRB 220513A: Global MASTER-Net observations report
  24. GRB 220511A: Swift/BAT-GUANO arcminute localization
  25. Fermi trigger No 673846271: Global MASTER-Net observations report
  26. GRB 220506A: MITSuME Akeno optical upper limits
  27. GRB 220506A: GIT optical upper limit.
  28. GRB 220506A/MAXI J1558-266: MAXI/GSC detection
  29. IPN triangulation of GRB 220423A
  30. IceCube-220501A: No Candidate Counterparts from the Zwicky Transient Facility
  31. IceCube Alert 220501.95: Global MASTER-Net observations report
  32. GRB 220426A: Swift-XRT and UVOT observations
  33. Konus-Wind detection of GRB 220426A
  34. Fermi trigger No 672492774: Global MASTER-Net observations report
  35. GRB 220421B: Detection by VZLUSAT-2
  36. Fermi GRB 220417A: Global MASTER-Net observations report
  37. Fermi trigger No 671729344: Global MASTER-Net observations report
  38. GRB 220412A: Continued RATIR Observations and Steepening of the Light Curve
  39. GRB 220408A: KAIT Optical Observations
  40. GRB 220408A: Swift detection of a burst with an optical counterpart, possibly associated with M51
  41. IceCube-220405A: No Candidate Counterparts from the Zwicky Transient Facility
  42. IceCube-220405B: No Candidate Counterparts from the Zwicky Transient Facility
  43. GRB 220404A: Swift-BAT refined analysis
  44. GRB 220404B: Fermi GBM Final Real-time Localization
  45. GRB 220403B: Nanshan/NEXT optical afterglow power-law decay
  46. Fermi GRB 220330A: Global MASTER-Net observations report
  47. GRB220319A: Optical observations from NOT
  48. IceCube-220317A: MASTER Global Robotic Net optical observations
  49. GRB 220315A: Fermi GBM Final Real-time Localization
  50. GRB 220308A: AGILE detection
  51. GRB 220310A: MAXI/GSC detection
  52. Fermi GRB 220309A: Global MASTER-Net observations report
  53. IPN triangulation of GRB 220305B
  54. Fermi trigger No 666962499: Global MASTER-Net observations report
  55. ZTF22aaajecp/AT2022cmc: Zeiss-1000 of Koshka observatory continued optical observations
  56. ZTF22aaajecp/AT2022cmc: Zeiss-1000 of Koshka observatory optical observations
  57. Fermi GRB 220209A: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 220128A
  59. Fermi GRB 220131A: Global MASTER-Net observations report
  60. GRB 220117C: Swift/BAT-GUANO arcminute localization
  61. Fermi trigger No 663966693: Global MASTER-Net observations report
  62. Fermi GRB 220111A: Global MASTER-Net observations report
  63. Fermi trigger No 663406755: Global MASTER-Net observations report
  64. GRB 220101A: TNG NIR afterglow detection
  65. Fermi trigger No 662768315: Global MASTER-Net observations report
  66. Fermi trigger No 662084433: Global MASTER-Net observations report
  67. GRB 211222A: Fermi GBM Final Real-time Localization
  68. GRB 211218A: MITSuME Akeno optical upper limits
  69. GRB 211106A: XMM-Newton monitoring campaign detections
  70. Fermi GRB 211216A: Global MASTER-Net observations report
  71. GRB 211211A: Further observations from CAFOS/2.2m CAHA
  72. Fermi GRB 211212B: Global MASTER-Net observations report
  73. Fermi GRB 211211B: Global MASTER-Net observations report
  74. Fermi trigger No 660868196: Global MASTER-Net observations report
  75. Fermi trigger No 660736561: Global MASTER-Net observations report
  76. Fermi GRB 211204C: Global MASTER-Net observations report
  77. GRB 211204C: Fermi GBM Final Real-time Localization
  78. Fermi GRB 211204B: Global MASTER-Net observations report
  79. GRB 211129A: Enhanced Swift-XRT position
  80. IPN triangulation of GRB 211118A
  81. GRB 211129A: Swift detection of a burst
  82. GRB 211120548: Fermi GBM observation
  83. IceCube Alert 211125.27: Global MASTER-Net observations report
  84. Fermi trigger No 659106591: Global MASTER-Net observations report
  85. Fermi trigger No 658971499: Global MASTER-Net observations report
  86. IceCube-211116A: No neutrino counterpart detected with ANTARES
  87. Fermi trigger No 658755664: Global MASTER-Net observations report
  88. Fermi trigger No 658764238: Global MASTER-Net observations report
  89. Fermi GRB 211112A: Global MASTER-Net observations report
  90. Fermi trigger No 658214822: Global MASTER-Net observations report
  91. GRB 211109B: Fermi GBM Final Real-time Localization
  92. GRB 211023B: MITSuME Akeno optical upper limits
  93. GRB 211102A: Fermi GBM Final Real-time Localization
  94. Fermi GRB 211031A: Global MASTER-Net observations report
  95. IPN triangulation of GRB 211022A
  96. GRB 211023A: continued Mondy optical observations
  97. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  98. Fermi GRB 211027A: Global MASTER-Net observations report
  99. GRB211023A: optical afterglow detection from Konkoly Observatory
  100. Swift GRB 211023B: Global MASTER-Net observations report

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