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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"

42673 results found.

  1. GRB040916: Archival optical observations
  2. XRF 040916, optical follow-up
  3. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  4. GRB040916: Optical observations
  5. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  6. GRB040916 (= H3558): Improved Localization from HETE WXM
  7. GRB040916 (= H3558): A Long XRF Localized by HETE
  8. GRB040912 (= H3557): Chandra Observations Scheduled
  9. GRB 040912: Optical Observations
  10. GRB/XRF040912,optical observations
  11. GRB 040912, BVRI observations
  12. An intense burst from SGR1806-20
  13. GRB040912 : Kiso Optical follow-up observation
  14. IBAS GRB Alerts 1978-1980
  15. Optical observations of field of GRB040912
  16. HETE 3557: Optical observations
  17. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  18. GRB040903 - A XRF?
  19. GRB040827: analysis of the XMM-Newton observation
  20. GRB040903, REM near-IR observation
  21. GRB 040903 - INTEGRAL data analysis
  22. IBAS Alert 1974. Not a real GRB
  23. Very bright burst detected from SGR 1806-20
  24. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  25. Possible GRB 040903 detected with INTEGRAL
  26. GRB 040827 - Radio Observations
  27. GRB040825A: Optical observations
  28. GRB 040827: optical and NIR observations at the VLT
  29. GRB 040827: UKIRT - 2nd epoch K-band imaging
  30. GRB 040827: 2nd epoch of Magellan K-band imaging
  31. GRB 040827: K imaging - no evidence of variability
  32. GRB 040827: Detection of NIR afterglow
  33. GRB 040827: Possible detection of optical afterglow
  34. GRB 040827: RTT150 optical observations
  35. GRB040827 XMM-Newton observation
  36. MASTER: GRB040827 possible OT
  37. GRB 040825B: Optical observations
  38. GRB040827 optical observations
  39. GRB 040827 - A long GRB detected by INTEGRAL
  40. GRB040825B, BVRcIc field photometry
  41. GRB040825A, BVRcIc field photometry
  42. Increase of SGR 1806-20 activity
  43. GRB040825A: optical observations
  44. GRB040825B: optical observations
  45. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  46. GRB 040825A: Optical observations.
  47. GRB 040825: Optical observations
  48. XRF040812: possible afterglow second Chandra observation
  49. GRB 040812: Second epoch CXO Observations
  50. GRB040823,optical observation
  51. XRF040812: GMRT observations
  52. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  53. XRF 040812: optical observation at VLT
  54. GRB 040812: Optical counterparts of CXO sources
  55. XRF040812: possible afterglow
  56. CXO observation of GRB 040812
  57. Bursting activity from SGR 1806-20 detected with IBAS
  58. IPN/HETE localizations of GRB040810 (=H3489)
  59. GRB 040812: Keck and LCO optical observations
  60. GRB 040812: Keck and LCO observations
  61. GRB 040812: radio observations
  62. GRB040812, optical/IR observations
  63. Konus-Wind observation of GRB040810 (=H3489)
  64. GRB 040812: a long GRB detected by INTEGRAL
  65. GRB 040810: Optical observations of a limited region
  66. XRF040701: Optical Observations at ESO
  67. IPN/HETE triangulation of GRB040802 (=H3485)
  68. GRB 040730, infrared observations
  69. GRB 040730: Optical observations
  70. GRB 040730: a long GRB detected with INTEGRAL
  71. Ongoing activity of SGR 1806-20
  72. GRB040624: optical monitoring at TNG
  73. XRF 040701 - optical observations of the decaying Chandra source
  74. XRF040701: Second-Epoch Chandra Observations
  75. XRF040701: VLA Observations
  76. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  77. XRF040701: First-Epoch Chandra Observations
  78. IBAS Alert 1836: NOT a real GRB
  79. GRB040709 J,H-band observations
  80. GRB040624, optical observations
  81. XRF 040701, optical observations
  82. XRF040701 (=U11548): a bright XRF detected by HETE
  83. GRB 040624: optical observations
  84. Optical Observations of GRB040624
  85. GRB 040624: optical observations at TNG and VLT
  86. GRB 040624: R-band observations
  87. GRB 040624, optical observations
  88. GRB 040624 - A long GRB detected with INTEGRAL
  89. GRB 030329: Rebrightening of hyperluminal ejecta.
  90. IPN Summary of SGR1806-20 Activity in 2004
  91. GRB040511: Retraction of redshift identification
  92. SGR 1806-20: no IR variability of the proposed counterparts
  93. SGR 1806-20, potential NIR counterpart
  94. GRB 040606: Optical observations
  95. Activivty of SGR 1806-20
  96. IPN triangulation of an intense intermediate burst from SGR1806-20
  97. GRB 040511, very fast decay?
  98. GRB 030324: Detection and Color of Host Galaxy
  99. GRB 040511: NIR observations with REM
  100. GRB040511: Redshift identifcation

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