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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"

28244 results found.

  1. GRB 110928A: P60 Observations
  2. GRB 110928A: Further PAIRITEL NIR Observations
  3. GRB 110928A: Swift-XRT observations
  4. GRB 110928A: Swift/UVOT finding chart observation
  5. GRB 110928A: Swift detection of a burst
  6. Swift-BAT trigger 503926 is noise
  7. GRB 110924A: Swift detection of a possible burst
  8. GRB110918A: Lick Observations
  9. GRB 110921A: NOT observations
  10. GRB 110921A: TNT astrometry
  11. GRB 110921A: Swift-XRT refined Analysis
  12. GRB 110918A: Liverpool Telescope optical observations
  13. GRB 110918A: submm observations from APEX
  14. GRB 110921A: optical observations in Mt. Terskol and Maidanak observatories
  15. GRB 110921A: Enhanced Swift-XRT position
  16. GRB 110921A: MITSuME Akeno Optical Observation
  17. GRB 110921A : TNT optical counterpart candidate
  18. GRB 110918A: Swift-XRT refined Analysis
  19. GRB 110918A: Spectroscopy from GTC
  20. GRB 110921A: Swift detection of a burst
  21. GRB 110915B : X-ray afterglow confirmation
  22. GRB 110918A: Swift/UVOT Detection of the Optical Counterpart
  23. GRB 110918A: rest-frame energetics in gamma-gays
  24. GRB 110918A: Gemini-N redshift
  25. GRB 110918A: Afterglow Confirmation from PTF
  26. GRB 110918A: GROND detection of the afterglow candidate
  27. GRB 110918A: INT optical detection of Swift candidate afterglow
  28. GRB 110918A: Swift-XRT observations
  29. MAXI/GSC detection of a short soft X-ray transient
  30. Swift detection of short bursts from PSR J1647-4552
  31. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  32. GRB 110915A: Swift/UVOT Upper Limits
  33. GRB 110915B: Swift/UVOT Upper Limits
  34. GRB 110915A: GROND Upper limits
  35. GRB 110915A: Swift-XRT refined Analysis
  36. GRB 110915B: Afterglow candidate from OSN
  37. GRB 110915A: Deep Near-IR Limits from Magellan
  38. GRB 110915B: XRT afterglow candidate
  39. GRB 110915A: Deep Gemini-South i/z-band imaging
  40. GRB110915A MITSuME Okayama J-band upper-limit
  41. GRB 110915A: MITSuME Okayama and Ishigakijima Optical upper limits
  42. GRB 110915A: NOT observations
  43. GRB 110915A: 1.23m CAHA I-band observations
  44. GRB 110915A: Enhanced Swift-XRT position
  45. GRB 110915A: GMG optical upper limit
  46. GRB 110915A: MITSuME Akeno Optical upper limits
  47. GRB 110915A: Prompt enhanced Swift-XRT position
  48. GRB 110915A: Swift detection of a burst
  49. GRB 110825A: Further Swift/XRT Observations
  50. GRB 110906A(?): Burst detection (unconfirmed) from Swift-BAT slew data
  51. GRB 110905A: Potential BAT trigger on MAXI J1836-194
  52. GRB 110905A: Swift detection of a burst
  53. GRB 110903A: Swift/UVOT Upper Limits
  54. GRB 110903A: Swift-XRT observations
  55. GRB 110820A: optical upper limit
  56. Trigger 502024: Swift detection of KS 1741-293
  57. Swift detection of an SGR burst from Swift J1834.9-0846
  58. GRB 110825A: GMG optical observation
  59. GRB110825A: ROTSE early time optical limit
  60. GRB 110825A: optical afterglow candidate
  61. GRB 110827A: Swift detection of a burst
  62. GRB 110825A: field inspection and possible host galaxy
  63. GRB110825A: Swift target of opportunity observation
  64. Swift-BAT Trigger 501485 is noise
  65. GRB 110820A: Swift/UVOT Upper Limits
  66. GRB 110820A: Position udpate + 2nd epoch data
  67. GRB 110820A: CQUEAN izY Observation
  68. GRB 110820A: Swift-XRT refined Analysis
  69. GRB110820A: MITSuME Ishigakijima Optical Upper Limits
  70. GRB 110820A: Enhanced Swift-XRT position
  71. GRB 110820A: CrAO optical upper limit
  72. GRB 110820A: Swift detection of a burst
  73. GRB 110818A: Swift/UVOT Upper Limits
  74. GRB 110818A: Enhanced Swift-XRT position
  75. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  76. GRB 110818A: Swift-XRT refined Analysis
  77. GRB 110815A: Swift-XRT and UVOT refined Analysis
  78. GRB 110818A: Swift detection of a burst
  79. GRB 110801A: optical observations at Mt. Terskol observatory
  80. Reprocessed enhanced Swift-XRT positions and GRB products: update
  81. SGR 1834.9-0846/ GRB 110807A, I-band observations
  82. A new photometric resource for GRB observers
  83. RXTE Discovery of the Spin Period of Swift J1834.9-0846
  84. SGR 1834.9-0846/ GRB 110807A: archival IR observations
  85. GRB 110808A: Swift/UVOT Detection
  86. GRB 110808A: Swift-XRT refined Analysis
  87. SGR J1834.9-0846: A Neutron Star in W41?
  88. Swift SGR 1834.9-0846: Swift-BAT refined analysis
  89. GRB 110808A: VLT/X-shooter spectroscopy
  90. GRB 110808A: Enhanced Swift-XRT position
  91. GRB 110808A: Swift detection of a burst with optical counterpart
  92. Fermi GBM detection of a SGR-like burst
  93. GRB 110807A: SAO RAS observations
  94. GRB 110807A: Swift detection of a burst or a posible new SGR
  95. Reprocessed enhanced Swift-XRT positions and GRB products
  96. EVLA observation for Fermi burst GRB 110721A
  97. GRB 110726A: Swift-XRT refined Analysis
  98. GRB110731A: MOA optical observations of the steeply fading afterglow
  99. GRB110801A: MITSuME Ishigakijima Optical Observation at 1 day after the burst
  100. GRB 110801A: Evidence for a jet break

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