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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"
  1. GRB 110820A: CrAO optical upper limit
  2. GRB 110820A: MASTER-NET observations
  3. GRB 110820A: Swift detection of a burst
  4. GRB 110818A: Fermi GBM observation
  5. GRB 110818A: Swift/UVOT Upper Limits
  6. GRB 110818A: Enhanced Swift-XRT position
  7. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  8. GRB 110818A: Swift-XRT refined Analysis
  9. GRB 110815A: Swift-XRT and UVOT refined Analysis
  10. GRB 110818A, Swift-BAT refined analysis
  11. GRB 110815A : Suzaku WAM observation of the prompt emission
  12. GRB 110818A: Swift detection of a burst
  13. Konus-Wind observation of GRB 110815A
  14. IPN triangulation of GRB110815A (long, intense)
  15. GRB 110801A: Konus-Wind and Swift/BAT joint spectral analysis
  16. GRB 110801A: optical observations at Mt. Terskol observatory
  17. GRB 110812A: SuperAGILE localization of a long GRB.
  18. Reprocessed enhanced Swift-XRT positions and GRB products: update
  19. SGR 1834.9-0846/ GRB 110807A, I-band observations
  20. Konus-Wind observation of GRB 110808B
  21. Konus-Wind observation of GRB 110808A
  22. IPN triangulation of GRB 110808B (short/hard/intense)
  23. A new photometric resource for GRB observers
  24. RXTE Discovery of the Spin Period of Swift J1834.9-0846
  25. SGR 1834.9-0846/ GRB 110807A: archival IR observations
  26. Fermi Gamma-ray Burst Monitor trigger 110809.346 is not a GRB
  27. GRB 110808A: Swift/UVOT Detection
  28. Swift Trigger 458942 is probably not a burst
  29. GRB 110808A: Swift-BAT refined analysis
  30. GRB 110808A: Swift-XRT refined Analysis
  31. SGR J1834.9-0846: A Neutron Star in W41?
  32. Swift SGR 1834.9-0846: Swift-BAT refined analysis
  33. GRB 110808A: VLT/X-shooter spectroscopy
  34. GRB 110808A: Enhanced Swift-XRT position
  35. GRB 110808A: Swift detection of a burst with optical counterpart
  36. Fermi GBM detection of a SGR-like burst
  37. GRB 110807A: SAO RAS observations
  38. GRB 110807A: Swift detection of a burst or a posible new SGR
  39. Fermi Gamma-ray Burst Monitor trigger 110806.263 is not a GRB
  40. GRB 110726A: two epochs of SAO RAS optical observations
  41. Reprocessed enhanced Swift-XRT positions and GRB products
  42. Konus-Wind observation of GRB 110802A
  43. Fermi GBM trigger 334123030 (110804165) is not a GRB
  44. IPN triangulation of GRB110802A (short/hard burst)
  45. GRB 110801A: optical observations in CrAO
  46. EVLA observation for Fermi burst GRB 110721A
  47. GRB 110731A : Suzaku WAM observation of the prompt emission
  48. GRB 110726A: Swift-XRT refined Analysis
  49. GRB110731A: MOA optical observations of the steeply fading afterglow
  50. GRB 110801A: SAO RAS optical observations
  51. GRB110801A: MITSuME Ishigakijima Optical Observation at 1 day after the burst
  52. GRB 110801A: Evidence for a jet break
  53. GRB 110801A: MASTER OT observations
  54. GRB 110801A: Swift-BAT refined analysis
  55. Swift/UVOT observations of GRB110801A
  56. GRB 110801A: Swift-XRT refined Analysis
  57. GRB 110801A: Afterglow redshift from 10.4m GTC
  58. GRB110801A: MITSuME Ishigakijima Optical Observation
  59. GRB 110801A: Enhanced Swift-XRT position
  60. AXP 4U 0142+61: Fermi GBM detection
  61. GRB 110801A: TLS Optical afterglow confirmation
  62. GRB 110801A: ROTSE-III Detection of re-brightening from OT
  63. GRB 110801A: Swift detection of a burst with an optical counterpart
  64. GRB 110731A / EVLA upper limits
  65. GRB110731A: MITSuME Ishigakijima Optical Upper Limits
  66. GRB 110731A Gemini-N redshift
  67. GRB 110731A: Swift-XRT refined Analysis
  68. Konus-Wind observation of GRB 110731A
  69. GRB110731A: Swift/UVOT Observations
  70. GRB 110731A: Fermi GBM observation
  71. GRB 110731A: NOT photometry
  72. GRB 110731A: Enhanced Swift-XRT position
  73. Fermi-LAT Detection of GRB110731A
  74. GRB 110731A: Swift-BAT refined analysis
  75. GRB 110731A: FTN+FTS afterglow observations
  76. GRB 110731A: Swift detection of a burst with an optical counterpart
  77. Sw J1644+57 (GRB 110328A): Continued VLBA Observations
  78. INTEGRAL Weak trigger #6331: GRT Optical Observation
  79. GRB 110721A: Swift observations of afterglow candidate
  80. AXP 4U 0142+61: Swift-BAT refined analysis
  81. GRB 110726A: optical upper limit in CrAO
  82. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  83. Swift triggers 458268 and 458269 are not astrophysical
  84. GRB 110726A: EVLA observations
  85. GRB 110726A: IAC80 R-band observations
  86. GRB 110726A: ROTSE-III refined analysis, fast decay in early phase
  87. GRB110726A: MITSuME Ishigakijima Optical Observation
  88. GRB 110726A: Further Swift/UVOT Observations
  89. GRB110726A: Gemini-N tentative redshift
  90. GRB 110726A: Swift-BAT refined analysis
  91. GRB 110726A: Enhanced Swift-XRT position
  92. GRB 110726A: Swift/UVOT Detection
  93. GRB 110726A: Liverpool Telescope observations
  94. GRB 110726: ROTSE-III Detection of Optical Counterpart
  95. GRB 110726A: Swift detection of a burst
  96. IPN triangulation of GRB 110721A
  97. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  98. GRB 110721A: Gemini-South spectroscopy of the potential optical counterpart
  99. GRB 110721A: potential counterpart candidate
  100. Konus-Wind observation of GRB 110721A

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