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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"

37756 results found.

  1. GRB 090423: CARMA mm observations
  2. GRB 090423: millimeter detection
  3. GRB 090426: Swift/BAT spectral lag results
  4. GRB 090425: Fermi GBM detection
  5. GRB 090424: Suzaku WAM observation of the prompt emission
  6. GRB 090426: VLT spectroscopy
  7. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  8. GRB 090426: Near infrared observation with ISLE at OAO
  9. GRB 090426: Okayama MITSuME optical observation
  10. GRB 090426 Keck LRIS redshift
  11. GRB 090426: Swift-BAT refined analysis
  12. GRB 090426: Swift-XRT refined analysis
  13. GRB 090423: GROND second epoch imaging and refined SED
  14. Detection of bright radio afterglow of GRB 090424 with the VLA
  15. GRB 090426: Enhanced Swift-XRT position
  16. GRB090426: Observation for Optical counterpart from MIRO
  17. GRB 090426, RIMOTS optical upper limits
  18. GRB 090426: inspection of SDSS images
  19. GRB 090426: TNT confimation of optical counterpart
  20. GRB 090426: Swift detection of a burst with an optical counterpart
  21. GRB 090424: MASTER-Net prompt optical limit
  22. GRB 090423: Fermi GBM observation (correction of isotropic equivalent energy)
  23. GRB 090424: WHT ISIS spectroscopy
  24. VLA radio observation of high-z GRB 090423
  25. GRB 090424 : Lulin 1m telescope optical observations
  26. GRB 090424: THO optical observations
  27. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  28. GRB 090424 Gemini-South Redshift
  29. GRB 090423: Y-band field calibration update/correction
  30. GRB 090423: Swift/BAT spectral lag results
  31. GRB 090424 : TAOS optical detection
  32. GRB 090424 optical observations
  33. GRB 090424: Liverpool Telescope observations
  34. GRB 090424: Swift-XRT refined analysis
  35. GRB 090424: Optical observations from 1.23m CAHA
  36. GRB 090423: energetic, luminosity and jet break
  37. Swift/UVOT observations of GRB 090424
  38. GRB 090424: MASTER-Net prompt optical observations
  39. GRB 090424: Enhanced Swift-XRT position
  40. GRB 090424: Swift-BAT refined analysis
  41. GRB 090424: Fermi GBM Observation
  42. GRB 090423: Fermi GBM observation
  43. GRB 090422: Fermi GBM observation
  44. GRB 090423: Ep,i - Eiso correlation
  45. GRB 090424: SDSS Galaxy at the Swift position
  46. GRB 090424: TNT optical observations
  47. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  48. GRB 090424: Swift detection of a burst with an optical counterpart
  49. GRB 090423: Refined TNG analysis
  50. GRB090423: Y-band field calibration
  51. GRB 090423 limiting magnitudes
  52. GRB 090423: VLT/ISAAC spectroscopy
  53. GRB 090423: Near infrared observation at Okayama Observatory
  54. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  55. GRB 090423: TNG Amici spectrum
  56. GRB 090423: GROND detection and preliminary photo-z
  57. GRB 090423: NOT z-band limit
  58. GRB 090423: Correction to NIR photometry
  59. GRB 090423: Swift-XRT refined analysis
  60. GRB090423 - Swift/UVOT upper limits.
  61. GRB 090423: NIR photometry and evidence for spectral break
  62. GRB 090422: Swift-XRT refined analysis
  63. GRB 090423: UKIRT data further analysis
  64. GRB 090423: Enhanced Swift-XRT position
  65. GRB 090423: Swift-BAT refined analysis
  66. GRB 090422: Swift/UVOT Upper Limits
  67. GRB 090423: UKIRT K-band observations
  68. GRB 090423: P60 Observations
  69. GRB 090423: Faulkes Telescope South observations
  70. GRB 090418A: R and I band observation
  71. GRB 090423: Swift detection of a burst
  72. GRB 090422: Liverpool Telescope possible candidate
  73. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  74. GRB 090422: Swift-BAT refined analysis
  75. GRB 090422: Enhanced Swift-XRT position
  76. GRB 090410: Erratum in GCN 9189
  77. GRB 090408A: Erratum in GCN 9188
  78. GRB 090418B: RTT150 optical observations
  79. GRB 090418A: RTT150 optical observations
  80. GRB 080410: GAO 150cm telescope Optical Observation
  81. GRB 080408A: GAO 150cm telescope Optical Observation
  82. GRB 090422: Liverpool Telescope observations
  83. GRB 090418B: Suzaku WAM observation of the prompt emission
  84. GRB 090422: Swift detection of a burst
  85. GRB 090418C: Fermi GBM Detection
  86. GRB 090418A: Swift/UVOT Detection of the Neighbouring Galaxy
  87. Swift-BAT trigger 349718 is not a burst
  88. GRB 090418B: GRAS002 observatios
  89. GRB 090417B: Optical observation
  90. GRB 090418A: optical observations
  91. GRB 090418B: GROND observations
  92. GRB 090419: Swift/UVOT Observations
  93. GRB 090418B: Faulkes Telescope North observations
  94. GRB 090418A: Swift/UVOT Observations
  95. GRB 090417B: Swift/UVOT Upper Limits
  96. GRB 090417B Correction to the BAT refined analysis position
  97. GRB 090419: Swift-XRT refined analysis
  98. Konus-Wind observation of GRB 090418B
  99. GRB 090418: Erratum in GCN 9168
  100. GRB 090419: GROND detection of afterglow candidate

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