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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"

32549 results found.

  1. GRB 041006: Optical afterglow candidate
  2. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  3. XRF 020903: Observations of the Host Galaxy (authors)
  4. XRF 020903: Observations of the Host Galaxy
  5. GRB 040924: Second Epoch WSRT Radio Observations
  6. radio observations, GRB 040924
  7. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  8. GRB040924,optical observation
  9. GRB040924, RTT150 optical observation
  10. GRB040924,optical observation
  11. GRB 040924: detection of possible host galaxy by Subaru
  12. GRB040924, RTT150 optical observation
  13. GRB040924: KAIT observations
  14. GRB040924: Afterglow magnitude at t=17.5hr
  15. GRB 040924: WSRT Radio Observations
  16. GRB 040924: NIR finding chart
  17. GRB040924 : Optical candidate observations at Lulin observatory
  18. GRB040924 : Optical candidate observations at Lulin observatory
  19. GRB 040924: Subaru NIR observation
  20. GRB 040924: RTT150 optical observations
  21. GRB 040924, optical follow-up
  22. GRB040924: MASTER: OT decay
  23. IPN triangulation of GRB040924 (H3564)
  24. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  25. XRF 040912: Radio Observations
  26. XRF 040916: Radio Observations
  27. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  28. XRF040916: continuing decay of OT
  29. TAROT Observations of GRB 040916 (HETE #3558)
  30. GRB040912(=H3557): Candidate Optical Afterglow
  31. XRF040916, optical observations
  32. XRF040916: Optical Transient Candidate by Subaru
  33. XRF 040912, identification of CXO sources
  34. XRF040916, Ic observations
  35. XRF040916: optical follow-up observations
  36. XRF040912, BVRcIc field calibration
  37. XRF040916, BVRcIc field calibration
  38. GRB040916: Archival optical observations
  39. XRF 040916, optical follow-up
  40. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  41. GRB040916: Optical observations
  42. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  43. GRB040916 (= H3558): A Long XRF Localized by HETE
  44. GRB040912 (= H3557): Chandra Observations Scheduled
  45. GRB 040912, BVRI observations
  46. GRB040912 : Kiso Optical follow-up observation
  47. IBAS GRB Alerts 1978-1980
  48. Optical observations of field of GRB040912
  49. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  50. GRB040903 - A XRF?
  51. GRB040827: analysis of the XMM-Newton observation
  52. GRB040903, REM near-IR observation
  53. GRB 040903 - INTEGRAL data analysis
  54. Very bright burst detected from SGR 1806-20
  55. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  56. Possible GRB 040903 - further analysis
  57. GRB 040827 - Radio Observations
  58. XMM-Newton Images of GRB 040827
  59. GRB040825A: Optical observations
  60. GRB040825A: Optical observations
  61. GRB 040827: optical and NIR observations at the VLT
  62. GRB 040827: UKIRT - 2nd epoch K-band imaging
  63. GRB 040827: 2nd epoch of Magellan K-band imaging
  64. GRB 040827: K imaging - no evidence of variability
  65. GRB 040827: Detection of NIR afterglow
  66. GRB 040827: Possible detection of optical afterglow
  67. GRB 040827: RTT150 optical observations
  68. MASTER: GRB040827 possible OT
  69. GRB 040825B: Optical observations
  70. GRB040827 optical observations
  71. GRB 040827 - Refined position
  72. GRB040825B, BVRcIc field photometry
  73. GCN GRB OBSERBATION REPORT
  74. GRB040825B: optical observations
  75. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  76. GRB040825B: Correction to GCN 2657
  77. XRF040812: possible afterglow second Chandra observation
  78. GRB 040812: Second epoch CXO Observations
  79. XRF040812: GMRT observations
  80. XRF 040812: optical observation at VLT
  81. GRB 040812: Optical counterparts of CXO sources
  82. XRF040812: possible afterglow
  83. CXO observation of GRB 040812
  84. IPN/HETE localizations of GRB040810 (=H3489)
  85. GRB 040812: Keck and LCO optical observations
  86. GRB 040812: Keck and LCO observations
  87. GRB 040812: radio observations
  88. GRB040812, optical/IR observations
  89. XRF040701: Optical Observations at ESO
  90. IPN/HETE triangulation of GRB040802 (=H3485)
  91. GRB 040730, infrared observations
  92. GRB 040730: Optical observations
  93. Ongoing activity of SGR 1806-20
  94. GRB040624: optical monitoring at TNG
  95. XRF 040701 - optical observations of the decaying Chandra source
  96. XRF040701: Second-Epoch Chandra Observations
  97. XRF040701: VLA Observations
  98. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  99. XRF040701: First-Epoch Chandra Observations
  100. GRB040709 J,H-band observations

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