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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"

37770 results found.

  1. GRB 230518B: VZLUSAT-2 detection
  2. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  3. Fermi trigger No 706328428: Global MASTER-Net observations report
  4. IPN triangulation of GRB 230518A (short)
  5. Fermi trigger No 706331483: Global MASTER-Net observations report
  6. Fermi trigger No 706317104: Global MASTER-Net observations report
  7. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  8. GRB 230521A: Fermi GBM Final Real-time Localization
  9. GRB 230520B is not a GRB
  10. GRB 230520B: Fermi GBM Final Real-time Localization
  11. GRB 230520A: MAXI/GSC detection
  12. GRB 230518A: Fermi GBM Observation
  13. LIGO/Virgo/KAGRA S230518h: Upper limits from Konus-Wind observations
  14. GRB 230518A: Swift/BAT-GUANO detection
  15. GRB 230518A: Fermi GBM Final Real-time Localization
  16. Fermi Gamma-ray Burst Monitor trigger 706068974/230518095 is not a GRB
  17. LIGO/Virgo/KAGRA S230518h: Upper limits from Fermi-GBM Observations
  18. LIGO/Virgo S230518h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  19. GRB 230513A: Zwicky Transient Facility continuous observations of a Fermi Short GRB (Trigger 705709044)
  20. GRB 230510B: GRBAlpha detection
  21. Fermi trigger No 706014351: Global MASTER-Net observations report
  22. GRB 230517A: BALROG localization (Fermi Trigger 706014351 / GRB 230517462)
  23. Improved IPN triangulation of GRB 230512A
  24. GRB 230517A: Fermi GBM Final Real-time Localization
  25. GRB 230510B: Fermi GBM detection
  26. Fermi trigger No 705952199: Global MASTER-Net observations report
  27. GRB 230516A: Fermi GBM Final Real-time Localization
  28. IPN triangulation of GRB 230511D (short)
  29. IPN triangulation of GRB 230512A
  30. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  31. GRB 230512A: Nanshan/NEXT non-detection of GRB afterglow candidate
  32. GRB 230512A: Zwicky Transient Facility non-detection of GRB afterglow candidate
  33. GRB 230512A: Liverpool Telescope observations
  34. GRB 230512A: GIT non detection of afterglow candidate
  35. GRB 230512A: Kitab possible afterglow candidate
  36. GRB 230512A: GRBAlpha detection
  37. GRB 230510A: GRBAlpha detection
  38. GRB 230513A: Fermi GBM Final Real-time Localization
  39. Fermi trigger No 705565670: Global MASTER-Net observations report
  40. Fermi-LAT gamma-ray observations of IceCube-230511A
  41. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  42. GRB 230512A: Swift-XRT observations
  43. GRB 230512A: GIT optical follow-up ZTF candidates
  44. GRB 230512A: Fermi GBM detection
  45. GRB 230512A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705565670)
  46. GRB 230430A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 704533643)
  47. GRB 230511D: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705537623)
  48. GRB 230512A: Tiled Swift observations
  49. GRB 230512A: Fermi-LAT detection
  50. GRB 230512A: AstroSat CZTI detection
  51. GRB 230512A: Fermi GBM Final Localization
  52. GRB 230510A: GIT optical upper limits
  53. GRB 230510A: LCOGT Optical Upper Limit
  54. GRB 230511D: Fermi GBM Final Real-time Localization
  55. GRB 230510A: Swift/UVOT Observations
  56. IceCube-230511A: IceCube observation of a high-energy neutrino candidate
  57. GRB 230510B: AstroSat CZTI detection
  58. GRB 230511C: Fermi GBM Final Localization
  59. Fermi trigger No 705503315: Global MASTER-Net observations report
  60. GRB 230511B: Fermi GBM Final Real-time Localization
  61. Fermi trigger No 705496510: Global MASTER-Net observations report
  62. GRB 230511A: Fermi GBM Final Real-time Localization
  63. GRB 230510A: Fermi GBM detection
  64. Fermi trigger No 705446499: Global MASTER-Net observations report
  65. GRB 230510A: Gaoyazi/GOT optical upper limit
  66. GRB 230510B: CALET Gamma-Ray Burst Monitor detection
  67. GRB 230510A: CALET Gamma-Ray Burst Monitor detection
  68. GRB 230510A: Nanshan/NEXT optical afterglow detection
  69. GRB 230510B: MAXI/GSC detection
  70. GRB 230510B: Fermi GBM Final Real-time Localization
  71. GRB 230506B: Fermi GBM detection
  72. GRB 230510A: Swift-XRT refined Analysis
  73. GRB 230510A: Enhanced Swift-XRT position
  74. GRB 230506C: Fermi GBM detection
  75. Fermi trigger No 705413051: Global MASTER-Net observations report
  76. Fermi Gamma-ray Burst Monitor trigger 230510133/705381054 is not a GRB
  77. GRB 230510A: Swift detection of a burst
  78. GRB 230510A: Fermi GBM Final Real-time Localization
  79. GRB 230506B: Swift/UVOT further analysis
  80. GRB 230506C: T193-OHP MISTRAL tentative redshift
  81. GRB 230506C: SAO RAS optical observations
  82. GRB 230307A: JWST second-epoch observations
  83. Fermi-LAT gamma-ray observations of IceCube-230506A
  84. GRB 230506C: Swift-XRT refined Analysis
  85. GRB 230506C: Swift-BAT refined analysis
  86. GRB 230506B: Swift-BAT refined analysis
  87. GRB 230506C: spectro-imaging observations of the optical afterglow with T193-OHP
  88. GRB 230506B: LCOGT Optical Upper Limits
  89. GRB 230506C: Swift/UVOT Upper Limits
  90. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  91. GRB 230506B: Swift-XRT refined Analysis
  92. GRB 230506C: Swift-XRT analysis
  93. GRB 230506C: Candidate afterglow observation by D50
  94. GRB 230506C: TSHAO possible afterglow candidate
  95. GRB 230506B: Swift/UVOT Detection
  96. IceCube-230506A: IceCube observation of a high-energy neutrino candidate
  97. GRB 230506C: Swift detection of a burst
  98. GRB 230506B: Swift detection of a burst
  99. GRB 230506B: MASTER optical observations
  100. GRB 230506B: Swift detection of a burst

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