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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. GRB041006, BVRcIc field calibration
  2. GRB 040924: VLT spectroscopy
  3. GRB 041006: SARA afterglow observations
  4. GRB041006, optical observation in CrAO
  5. Search for SN light in XRF 040912 with MEGACAM
  6. GRB 040916: Afterglow Color at Early Times
  7. GRB 041006 Optical afterglow observations
  8. IBAS GRB Alert # 2010
  9. GRB 041006: BR observations with VATT
  10. GRB 041006: Redshift confirmed
  11. GRB041006: Liverpool Telescope optical observations
  12. GRB 041006: Colour measurement
  13. GRB041006: break in the light curve
  14. GRB 041006: Radio Observations
  15. GRB041006, further submilllimetre observations
  16. GRB 041006 : optical follow-up observation at Lulin Observatory
  17. SUBJECT: GRB 041006 : Optical follow-up observation at TAROT
  18. GRB041006: Optical photometry and spectroscopy at TNG
  19. GRB 041006: presice astrometry
  20. GRB041006 (= H3570): Chandra Observations In Progress
  21. GRB 041006 : optical observation at Bisei
  22. GRB041006, optical I observation
  23. GRB041006 (=HETE3570): optical observations
  24. ROTSE-IIIa Observations of GRB 041006
  25. GRB041006, optical observation
  26. GRB041006, submillimetre observations
  27. GRB041006: MASTER optical observations
  28. GRB041006,optical observation
  29. GRB 041006: Optical decay
  30. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  31. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  32. GRB041006: Fading of optical afterglow candidate
  33. GRB 041006 : Optical follow-up observation at KISO
  34. GRB 041006: Finding chart
  35. GRB 041006: Optical afterglow candidate
  36. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  37. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  38. XRF 020903: Observations of the Host Galaxy (authors)
  39. XRF 020903: Observations of the Host Galaxy
  40. SGR 1806-20 still active
  41. GRB 040924: Second Epoch WSRT Radio Observations
  42. radio observations, GRB 040924
  43. IBAS Alert 1991. Not a real GRB
  44. GRB040929,optical observation
  45. GRB040929: MASTER optical observations
  46. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  47. GRB040924,optical observation
  48. GRB040924, RTT150 optical observation
  49. GRB040924,optical observation
  50. GRB 040924: detection of possible host galaxy by Subaru
  51. GRB040924, RTT150 optical observation
  52. GRB040924: KAIT observations
  53. GRB040924: Afterglow magnitude at t=17.5hr
  54. GRB 040924: WSRT Radio Observations
  55. GRB 040924: NIR finding chart
  56. GRB040924 : Optical candidate observations at Lulin observatory
  57. GRB040924 : Optical candidate observations at Lulin observatory
  58. GRB 040924: Subaru NIR observation
  59. GRB040924: Optical afterglow properties
  60. GRB 040924: RTT150 optical observations
  61. GRB 040924, optical follow-up
  62. GRB040924: MASTER: OT decay
  63. GRB040924: MASTER Optical observations
  64. IPN triangulation of GRB040924 (H3564)
  65. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  66. GRB040924 (H3564): Optical afterglow candidate
  67. XRF 040912: Radio Observations
  68. XRF 040916: Radio Observations
  69. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  70. XRF040916: continuing decay of OT
  71. TAROT Observations of GRB 040916 (HETE #3558)
  72. GRB040912(=H3557): Candidate Optical Afterglow
  73. XRF040916, optical observations
  74. XRF040916: Optical Transient Candidate by Subaru
  75. GRB040916 optical limits 17 min after GRB
  76. XRF 040912, identification of CXO sources
  77. XRF 040912 (=H3557): Spectral and Temporal Properties
  78. XRF040916, Ic observations
  79. XRF040916: optical follow-up observations
  80. XRF040912, BVRcIc field calibration
  81. XRF040916, BVRcIc field calibration
  82. GRB040916: Archival optical observations
  83. XRF 040916, optical follow-up
  84. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  85. GRB040916: Optical observations
  86. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  87. GRB040916 (= H3558): Improved Localization from HETE WXM
  88. GRB040916 (= H3558): A Long XRF Localized by HETE
  89. GRB040912 (= H3557): Chandra Observations Scheduled
  90. GRB 040912: Optical Observations
  91. GRB/XRF040912,optical observations
  92. GRB 040912, BVRI observations
  93. Optical observations of GRB/XRF 040912 = HETE 3557
  94. An intense burst from SGR1806-20
  95. GRB040912 : Kiso Optical follow-up observation
  96. IBAS GRB Alerts 1978-1980
  97. Optical observations of field of GRB040912
  98. HETE 3557: Optical observations
  99. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  100. GRB 040827: XMM-Newton data

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