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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"

19697 results found.

  1. GRB 090807, RIMOTS optical upper limits
  2. GRB 090807: Swift detection of a burst
  3. GRB 090802: Fermi GBM detection
  4. GRB 090726: optical observation
  5. Swift trigger 358760 is probably a noise event
  6. GRB 090727: GRT Optical Observation
  7. GRB 090726: GRT Optical Observation
  8. GRB 090727: Swift/UVOT Upper Limits
  9. GRB 090728: Swift/UVOT Upper Limits
  10. GRB 090728: Enhanced Swift-XRT position
  11. GRB 090728, RIMOTS optical upper limits
  12. GRB 090728: Swift detection of a burst
  13. GRB 090727: Enhanced Swift-XRT position
  14. GRB 090715B: Late-time Lick 3m observations
  15. GRB 090727: Swift detection of a burst
  16. GRB090726: Swift/UVOT observations
  17. GRB 090711: Fermi GBM detection
  18. GRB 090726: Enhanced Swift-XRT position
  19. GRB 090726: optical transient candidate
  20. GRB 090726: Swift/UVOT Finding Chart Observation
  21. Konus-Wind observations of bright hard GRB 090720B
  22. GRB 090720B: Fermi GBM detection
  23. Swift XRT and UVOT refned analysis of GRB 090720
  24. GRB 090709A: Swift XRT Timing Analysis
  25. GRB 090715B: VLA radio detection
  26. GRB 090720 Source found in ground processing of Swift-BAT data
  27. GRB 090717B: Fermi GBM detection
  28. GRB 090717: Fermi GBM detection
  29. GRB 090719: Fermi GBM detection
  30. GRB 090718B: Fermi GBM detection
  31. GRB 090720: Fermi GBM detection
  32. GRB 090715B: further NOT optical observations
  33. GRB 090709A - CARMA mm Observations
  34. GRB 090715A: VLA observations
  35. GRB 090715B: Swift/UVOT followup observations
  36. GRB 090715B: Enhanced Swift-XRT position
  37. GRB 090715B: Observation of the optical afterglow
  38. GRB 090715B: NOT optical observations
  39. GRB 090715B: Swift detection of a burst with a possible optical counterpart
  40. GRB 090712: Fermi GBM observation
  41. GRB 090713: Fermi GBM detection
  42. VLA radio observations of GRB 090709A
  43. GRB 090621B: MTM-500 optical observations
  44. GRB 090709A: deep optical observation with the 10.4m GTC
  45. GRB 090709A: Swift UVOT upper limits
  46. GRB 090709A: WHT LIRIS observations
  47. GRB 090709B: Fermi GBM detection
  48. GRB 090709A: confirmation of the periodicity in the SPI-ACS data
  49. GRB 090709A: P60 Observations
  50. GRB 090709A: Quasiperiodic variations in the BAT light curve
  51. GRB 090709A: NOT optical observations
  52. GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
  53. GRB090709A: High Energy BAT/XRT Analysis Suggests Low to Moderate Redshift
  54. GRB 090709A: Wyoming Infrared Observatory NIR upper limits
  55. GRB 090709A, RIMOTS optical upper limits
  56. GRB 090709A: Enhanced Swift-XRT position
  57. GRB 090709A: Subaru NIR observation
  58. GRB 090709 : planned Suzaku-ToO observation
  59. GRB 090708 : Fermi GBM detection
  60. GRB 090709: Faulkes Telescope North Upper Limits
  61. GRB 090709: PAIRITEL NIR Upper Limits
  62. GRB 090704: Fermi GBM observation
  63. GRB 090709: Swift detection of a bright burst
  64. GRB 090708: Early RAPTOR Optical Limits
  65. GRB 090708, Swift-BAT refined analysis
  66. GRB 090706: Fermi GBM detection
  67. GRB 090705: PAIRITEL NIR Observations
  68. GRB 090705: Swift detection of a possible burst
  69. XRF 090702 : RTT150 optical observations
  70. GRB 090529: CrAO optical upper limit
  71. GRB 090529: MTM-500 optical observations
  72. GRB 090703: Fermi GBM detection
  73. GRB 090702: UVOT upper limits
  74. XRF 090702: VLT imaging
  75. XRF 090702: Swift-XRT afterglow position
  76. GRB 090404: Deep optical imaging and possible host association
  77. GRB 090701: Fermi GBM detection
  78. GRB 090630: Fermi GBM detection
  79. GRB 090628: Swift/UVOT Upper Limits
  80. GRB080628: SAO RAS optical observations
  81. GRB 090628: GROND upper limits
  82. GRB 090628: Enhanced Swift-XRT position
  83. GRB 090626: IPN localization
  84. GRB 090628: Swift/UVOT Finding Chart Observation
  85. GRB 090625B: Fermi GBM observation
  86. GRB 090423: Spitzer observations of the z~8.3 burst
  87. GRB 090625B: Swift/UVOT Upper Limits
  88. GRB 090626: Fermi GBM detection
  89. GRB 090625B: GROND upper limits
  90. GRB090618: HCT optical observations
  91. GRB 090618: SARA Second Epoch Observations
  92. GRB 090625B: Swift observation of the INTEGRAL GRB 090625B
  93. GRB 090625: Fermi GBM detection
  94. GRB 090621A: Enhanced Swift-XRT position
  95. GRB 090623: Fermi GBM detection
  96. GRB 090621B: GRT Optical Observation
  97. GRB 090621A: GRT Optical Observation
  98. GRB 090621B: Fermi GBM detection
  99. GRB 090621B: I-band observations from 1.23m CAHA
  100. GRB 090621D: Fermi GBM detection

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