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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"
  1. SGR 0501+4516: Detection of possible optical counterpart
  2. SGR 0501+4516: WHT observations of the possible near-infrared counterpart
  3. GRB080825B: Swift/UVOT Upper Limits
  4. GRB 080828: Swift-XRT detection of a possible X-ray afterglow
  5. Swift-BAT trigger 322590 is not a GRB
  6. VLA non-detection of SGR 0501+4516
  7. Radio Detection of SGR 0501+4516: Retraction
  8. Swift trigger 322590: BAT detection of a possible burst
  9. SGR 0501+4516: XMM-Newton monitoring schedule
  10. GRB 080828: SuperAGILE GRB Localization
  11. SGR 0501+4516: Decline in Activity
  12. SGR 0501+4516: Proximity to supernova remnant HB9
  13. Enhanced Swift-XRT position of SGR 0501+4516
  14. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  15. SGR 0501+4516: Swift XRT measure of the spin period
  16. GRB080823: Fermi Gamma-ray Burst Monitor detection
  17. GRB 080824: Fermi Gamma Ray Burst Monitor detection
  18. GRB 080825B: pseudo-z= 0.83 from prompt emission spectrum
  19. Konus-Wind observation of GRB 080825B
  20. GRB080825C: GLAST Burst Monitor detection
  21. GRB 080825B: Swift-XRT team analysis
  22. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  23. Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
  24. GRB080825: Afterglow confirmation and redshift estimate
  25. Suzaku ToO Observation of SGR 0501+4516
  26. GRB 080825B - optical counterpart candidate
  27. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  28. GRB 080825B: GRB Localization by SuperAGILE
  29. Konus-Wind observations of new SGR 0501+4516
  30. INTEGRAL ToO Observation of SGR0501+4516
  31. Radio Detection of SGR 0501+4516
  32. SGR 0501+4516: MDM Optical Observations
  33. GRB 080822B, Swift-BAT refined analysis
  34. SGR 0501+4516: Astrotel-Caucasus optical observations
  35. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  36. SGR 0501+4516: WSRT Radio Observations
  37. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  38. GRB 080822B: MASTER optical observation
  39. New Soft Gamma Repeater 0501+4516 (GRB 080822): GLAST Burst Monitor detection
  40. SGR 0501+4516: optical observations
  41. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  42. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  43. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  44. GRB 080822B: Swift detection of a burst
  45. GRB080818B: GLAST Burst Monitor detection
  46. Third event from SGR 0501+4516
  47. GRB 080822 (SGR 0501+4516): archival optical observations
  48. New Soft Gamma Repeater 0501+4516 was GRB 080822
  49. GRB 080822: Swift detection of a short burst
  50. GLAST Burst Monitor detection of a GRB: 080816B
  51. GLAST Burst Monitor detection of GRB 080818
  52. GLAST Burst Monitor detection of GRB080817B
  53. GLAST Burst Monitor detection of GRB 080817
  54. GLAST Burst Monitor detection of GRB080816
  55. GRB080810 - optical observations
  56. GRB080810: optical observations
  57. GLAST Burst Monitor detection of GRB 080812
  58. Radio detection of GRB 080810 with the VLA
  59. GRB 080810: RTT150 optical observations
  60. GRB 080810: Konus-Wind and Swift/BAT joint spectral analysis
  61. GLAST Burst Monitor detection of GRB 080810
  62. GRB 080810: Liverpool and Faulkes North observations
  63. GRB 080810: RTT150 optical observations
  64. GRB080810: MITSuME optical observation
  65. First GLAST Burst Monitor GRB Circulars
  66. GRB 080810: Swift/UVOT Refined Analysis
  67. GRB 080810: optical observations
  68. GRB 080810: Liverpool Telescope observations
  69. GRB 080810: D50 optical observation
  70. GRB 080810: Kanazawa optical observation
  71. GRB 080810: OSN follow-up
  72. GRB 080810: Observations from NOT
  73. GRB 080810: RTT150 optical observations
  74. GRB 080810: Swift-XRT Team refined analysis
  75. GRB 080810: Enhanced Swift-XRT position
  76. GRB 080810: KANATA optical-NIR observation, update
  77. GRB 080810: ROTSE-III Prompt Detection of Optical Counterpart
  78. GRB 080810: Keck/HIRES Spectroscopy
  79. GRB 080810, Swift-BAT refined analysis
  80. GRB 080810 : optical observation with KANATA
  81. GRB 080810: Swift detection of a burst with a bright optical afterglow
  82. GRB 080723B: GROND upper limits
  83. GRB 080723B: XMM-Newton observation
  84. GRB 080805: VLT redshift update
  85. GRB 080805: Faulkes Telescope South optical observations
  86. GRB 080804: GROND observations
  87. GRB 080727B: Late VLT imaging
  88. GRB 080804: ATCA Radio Observations
  89. GRB 080805: Swift-XRT Refined Analysis
  90. GRB 080805: Swift/UVOT Upper Limits
  91. GRB 080804: Swift-XRT Refined Analysis
  92. GRB 080804: Swift/UVOT Refined Analysis
  93. GRB 080805, Swift-BAT refined analysis
  94. GRB 080804, Swift-BAT refined analysis
  95. GRB 080804: Enhanced Swift-XRT position
  96. GRB080804: Gemini South redshift confirmation
  97. GRB 080804: Faulkes Telescope South observations
  98. GRB080805 optical limit by "Pi of the Sky"
  99. GRB 080805: VLT redshift
  100. GRB 080805: Afterglow confirmation

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