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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"

42828 results found.

  1. GRB 120404A: optical observations
  2. GRB 120404A: JCMT SCUBA-2 sub-mm observation
  3. GRB 120404A: SMARTS optical/IR observations
  4. GRB 120404A: EVLA Detection
  5. GRB 120404A: MASTER OT observations
  6. GRB120404A: GROND observations show steeply decaying afterglow
  7. GRB120404A: MOA optical observations of the initial rise afterglow
  8. GRB 120404A: VLT/X-shooter redshift confirmation
  9. GRB 120404A: Swift/UVOT Detection
  10. GRB 120403B: Swift-XRT refined Analysis
  11. GRB 120404A: Swift-XRT refined Analysis
  12. GRB 120404A : TNT optical observation
  13. GRB 120404A: Swift-BAT refined analysis
  14. GRB 120401A: GROND Detection of an optical/NIR afterglow candidate
  15. GRB 120404A: Enhanced Swift-XRT position
  16. GRB 120404A: Gemini-N Redshift correction
  17. GRB 120402B: MASTER early OT limit
  18. GRB 120403B: TAROT La Silla observatory optical observations
  19. GRB 120403B: Fermi GBM Observation
  20. GRB 120404A: Gemini-N Redshift
  21. GRB 120404A: MASTER early OT limit
  22. GRB 120404A: Faulkes Telescope North afterglow confirmation
  23. GRB 120404A: Swift detection of a burst with an optical counterpart
  24. GRB 120403B: Swift-BAT refined analysis
  25. GRB 120403B: Swift/UVOT Upper Limits
  26. GRB 120403B: Enhanced Swift-XRT position
  27. GRB 120403A: Swift/BAT spectral lag analysis
  28. GRB 120403B: Swift detection of a burst
  29. BAT trigger 519207 was a burst from Cyg X-1, was not GRB 120402A
  30. GRB 120402A: optical upper limit
  31. GRB 120320A: optical upper limit in Mondy observatory
  32. GRB 120320A: early optical upper limit
  33. GRB 120403A: MASTER follow up observations
  34. GRB 120402A: MASTER follow up observations
  35. GRB 120403A, Swift-BAT refined analysis
  36. GRB 120402B: Fermi GBM detection
  37. GRB 120403A: Swift detection of a burst
  38. GRB 120402A: Swift detection of a possible burst or noise
  39. GRB 120326A: Cima Rest and Bassano Brescia
  40. GRB 120327A: SMARTS optical/IR afterglow observations
  41. GRB 120401A: Swift-XRT refined Analysis
  42. GRB 120401A: Swift-BAT refined analysis
  43. GRB 120401A: Enhanced Swift-XRT position
  44. GRB 120401A: Prompt enhanced Swift-XRT position
  45. GRB 120401A: Swift detection of a burst
  46. GRB 120326A: EVLA Observations
  47. GRB120327A - ATCA radio afterglow detection at 34GHz
  48. GRB 120324A: CrAO optical upper limit
  49. GRB 120326A : Suzaku WAM observation of the prompt emission
  50. GRB 120326A: CARMA 3mm detection
  51. Swift trigger 518853 is most likely GX 301-2
  52. Swift trigger 518853: MASTER-ICATE possible OT
  53. The Swift-XRT source associated with trigger 518853 is a cosmic ray
  54. Trigger 518853: Swift detection of a probable Galactic transient
  55. GRB 120328B: Fermi-LAT Observations
  56. GRB 120327A: Zadko optical observations
  57. GRB 120328B: Fermi GBM detection
  58. long/intense GRB 120328B: MASTER follow up observations
  59. GRB 120328A: Swift/UVOT Upper Limits
  60. GRB 120326A: Bassano Bresciano Observatory further optical observations
  61. GRB 120328A: Swift-XRT refined Analysis
  62. Konus-Wind observation of GRB 120328B
  63. IPN Triangulation of GRB 120328B (long/intense)
  64. GRB 120328A: Swift-BAT refined analysis
  65. GRB 120328A: Enhanced Swift-XRT position
  66. GRB 120327A: NOT optical observations
  67. GRB 120328A: TAROT La Silla observatory optical observations
  68. GRB 120326A: Xinglong TNT further optical observation��correction for GCN Cir 13149)
  69. GRB 120326A: Xinglong TNT further optical observation
  70. Skynet/PROMPT observations of GRB120328A
  71. GRB 120328A: Swift detection of a burst
  72. GRB 120327A: GTC redshift confirmation
  73. GRB 120326A: Fermi GBM Observation
  74. GRB 120327A afterglow detection
  75. GRB 120326A: PAIRITEL NIR Observations
  76. GRB 120327A: Swift-XRT refined Analysis
  77. GRB 120326A: LOAO R-band Observations
  78. GRB 120327A: Swift/UVOT further analysis
  79. GRB 120327A: Swift-BAT refined analysis
  80. GRB 120326A : SMA submm observation
  81. GRB 120327A: Enhanced Swift-XRT position
  82. GRB 120327A: X-shooter redshift
  83. GRB 120327A: Gemini-South redshift
  84. GRB 120327A: TAROT La Silla observatory optical decay
  85. GRB120326A: TNT optical observation
  86. GRB 120327A: IAC80 I-band observations
  87. GROND observations of GRB 120327A
  88. GRB 120327A: REM NIR and optical observations
  89. Skynet/PROMPT observations of GRB120327A
  90. GRB 120326A: Maisoncelles Observatory optical observations
  91. GRB 120327A: TAROT La Silla observatory optical detection
  92. GRB 120327A: Swift detection of a burst with an optical counterpart
  93. GRB 120326A: optical observation of GMG
  94. GRB 120326A: Swift-BAT refined analysis
  95. GRB 120326A: T17 optical observations
  96. GRB 120326A: GTC redshift
  97. GRB 120323A: MASTER follow up observations
  98. GRB 120326A: Swift-XRT refined Analysis
  99. GRB 120326A: Swift/UVOT Detection
  100. GRB120326A: IAC80 observations

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