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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"

39383 results found.

  1. Fermi trigger No 706014351: Global MASTER-Net observations report
  2. GRB 230517A: BALROG localization (Fermi Trigger 706014351 / GRB 230517462)
  3. Improved IPN triangulation of GRB 230512A
  4. GRB 230517A: Fermi GBM Final Real-time Localization
  5. GRB 230510B: Fermi GBM detection
  6. Fermi trigger No 705952199: Global MASTER-Net observations report
  7. GRB 230516A: Fermi GBM Final Real-time Localization
  8. IPN triangulation of GRB 230511D (short)
  9. IPN triangulation of GRB 230512A
  10. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  11. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  12. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate
  13. GRB 230512A: Liverpool Telescope observations
  14. GRB 230512A: GIT non detection of afterglow candidate
  15. GRB 230512A: Kitab possible afterglow candidate
  16. GRB 230512A: GRBAlpha detection
  17. GRB 230510A: GRBAlpha detection
  18. GRB 230513A: Fermi GBM Final Real-time Localization
  19. Fermi trigger No 705565670: Global MASTER-Net observations report
  20. Fermi-LAT gamma-ray observations of IceCube-230511A
  21. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  22. GRB 230512A: Swift-XRT observations
  23. GRB 230512A: GIT optical follow-up ZTF candidates
  24. GRB 230512A: Fermi GBM detection
  25. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  26. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  27. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  28. GRB 230512A: Tiled Swift observations
  29. GRB 230512A: Fermi-LAT detection
  30. GRB 230512A: AstroSat CZTI detection
  31. GRB 230512A: Fermi GBM Final Localization
  32. GRB 230510A: GIT optical upper limits
  33. GRB 230510A: LCOGT Optical Upper Limit
  34. GRB 230511D: Fermi GBM Final Real-time Localization
  35. GRB 230510A: Swift/UVOT Observations
  36. IceCube-230511A: IceCube observation of a high-energy neutrino candidate
  37. GRB 230510B: AstroSat CZTI detection
  38. GRB 230511C: Fermi GBM Final Localization
  39. Fermi trigger No 705503315: Global MASTER-Net observations report
  40. GRB 230511B: Fermi GBM Final Real-time Localization
  41. Fermi trigger No 705496510: Global MASTER-Net observations report
  42. GRB 230511A: Fermi GBM Final Real-time Localization
  43. GRB 230510A: Fermi GBM detection
  44. Fermi trigger No 705446499: Global MASTER-Net observations report
  45. GRB 230510A: Gaoyazi/GOT optical upper limit
  46. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  47. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  48. GRB 230510A: Nanshan/NEXT optical afterglow detection
  49. GRB 230510B: MAXI/GSC detection
  50. GRB 230510B: Fermi GBM Final Real-time Localization
  51. GRB 230506B: Fermi GBM detection
  52. GRB 230510A: Swift-XRT refined Analysis
  53. GRB 230510A: Enhanced Swift-XRT position
  54. GRB 230506C: Fermi GBM detection
  55. Fermi trigger No 705413051: Global MASTER-Net observations report
  56. Fermi Gamma-ray Burst Monitor trigger 230510133/705381054 is not a GRB
  57. GRB 230510A: Swift detection of a burst
  58. GRB 230510A: Fermi GBM Final Real-time Localization
  59. GRB 230506B: Swift/UVOT further analysis
  60. GRB 230506C: T193-OHP MISTRAL tentative redshift
  61. GRB 230506C: SAO RAS optical observations
  62. GRB 230307A: JWST second-epoch observations
  63. Fermi-LAT gamma-ray observations of IceCube-230506A
  64. GRB 230506C: Swift-XRT refined Analysis
  65. GRB 230506C: Swift-BAT refined analysis
  66. GRB 230506B: Swift-BAT refined analysis
  67. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  68. GRB 230506B: LCOGT Optical Upper Limits
  69. GRB 230506C: Swift/UVOT Upper Limits
  70. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  71. GRB 230506B: Swift-XRT refined Analysis
  72. GRB 230506C: Swift-XRT analysis
  73. GRB 230506C: Candidate afterglow observation by D50
  74. GRB 230506C: TSHAO possible afterglow candidate
  75. GRB 230506B: Swift/UVOT Detection
  76. IceCube-230506A: IceCube observation of a high-energy neutrino candidate
  77. GRB 230506C: Swift detection of a burst
  78. Swift GRB230506.71: Global MASTER-Net observations report
  79. GRB 230506B: Swift detection of a burst
  80. GRB 230506B: MASTER optical observations
  81. GRB 230506B: Swift detection of a burst
  82. GRB 230506A: Fermi GBM Final Real-time Localization
  83. GRB 230420A: Mondy optical afterglow detection, TSHAO, CrAO optical upper limit
  84. Fermi trigger No 704837952: Global MASTER-Net observations report
  85. GRB 230430A: A short GRB from a neutron star merger
  86. GRB 230427A: Swift-BAT refined analysis
  87. GRB 230503A: Fermi GBM Final Real-time Localization
  88. Konus-Wind detection of GRB 230430A
  89. IPN triangulation of GRB 230430A (short)
  90. GRB 230420A: AROMA-N Optical Upper Limit
  91. GRB 230430B: Fermi GBM Final Localization
  92. GRB 230430A: Fermi GBM observation
  93. GRB 230430A: AstroSat CZTI detection
  94. GRB 230430A: Fermi GBM Final Real-time Localization
  95. GRB 230427A: NOT optical upper limit
  96. GRB 230427A: TSHAO, SAO RAS, AbAO optical upper limit
  97. GRB 230427A: Swift/UVOT Detection
  98. GRB 230427A: Gaoyazi/GOT optical upper limit
  99. GRB 230427A: OHP/T193 spectroscopy observations of WISEA J101316.01+481158.7
  100. GRB 230427A: Nanshan/HMT optical upper limit

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