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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"

28233 results found.

  1. XRF 040912, identification of CXO sources
  2. XRF040912, BVRcIc field calibration
  3. XRF040916, BVRcIc field calibration
  4. GRB040916: Archival optical observations
  5. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  6. GRB040916: Optical observations
  7. GRB040912 (= H3557): Chandra Observations Scheduled
  8. GRB 040912: Optical Observations
  9. GRB/XRF040912,optical observations
  10. GRB 040912, BVRI observations
  11. Optical observations of field of GRB040912
  12. HETE 3557: Optical observations
  13. GRB040903 - A XRF?
  14. GRB040827: analysis of the XMM-Newton observation
  15. GRB040903, REM near-IR observation
  16. Very bright burst detected from SGR 1806-20
  17. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  18. Possible GRB 040903 - further analysis
  19. GRB 040827 - Radio Observations
  20. XMM-Newton Images of GRB 040827
  21. GRB 040827: optical and NIR observations at the VLT
  22. GRB 040827: UKIRT - 2nd epoch K-band imaging
  23. GRB 040827: 2nd epoch of Magellan K-band imaging
  24. GRB 040827: K imaging - no evidence of variability
  25. GRB 040827: Detection of NIR afterglow
  26. GRB040827 XMM-Newton observation
  27. GRB040825A: optical limit before GRB
  28. GRB 040825B: Optical observations
  29. GRB 040827 : Planned XMM-Newton observation
  30. GRB040825B, BVRcIc field photometry
  31. GRB040825A, BVRcIc field photometry
  32. GCN GRB OBSERBATION REPORT
  33. GRB 040825A,optical observations
  34. GRB040825A: optical observations
  35. GRB040825B: optical observations
  36. MASTER: GRB040825b optical observation
  37. GRB 040825: Optical observations
  38. XRF040812: possible afterglow second Chandra observation
  39. GRB 040812: Second epoch CXO Observations
  40. GRB040823,optical observation
  41. XRF040812: GMRT observations
  42. XRF 040812: optical observation at VLT
  43. GRB 040812: Optical counterparts of CXO sources
  44. XRF040812: possible afterglow
  45. CXO observation of GRB 040812
  46. GRB 040812: radio observations
  47. GRB040812, optical/IR observations
  48. GRB 040812: a long GRB detected by INTEGRAL
  49. XRF040701: Optical Observations at ESO
  50. GRB 040730, infrared observations
  51. GRB 040730: a long GRB detected with INTEGRAL
  52. Ongoing activity of SGR 1806-20
  53. GRB040624: optical monitoring at TNG
  54. XRF 040701 - optical observations of the decaying Chandra source
  55. XRF040701: Second-Epoch Chandra Observations
  56. XRF040701: VLA Observations
  57. XRF040701: First-Epoch Chandra Observations
  58. GRB040624, optical observations
  59. GRB040706:observation at University of Miyazaki
  60. Optical Observations of GRB040624
  61. GRB 040624: optical observations at TNG and VLT
  62. MASTER: GRB 040624 optical observation after 0,48d
  63. GRB 040624, optical observations
  64. GRB 040624 - A long GRB detected with INTEGRAL
  65. GRB 030329: Rebrightening of hyperluminal ejecta.
  66. IPN Summary of SGR1806-20 Activity in 2004
  67. SGR 1806-20: no IR variability of the proposed counterparts
  68. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  69. SGR 1806-20, potential NIR counterpart
  70. GRB 040606: Optical observations
  71. MASTER: HETE Alert 3274 optical observation
  72. Activivty of SGR 1806-20
  73. GRB 040511, very fast decay?
  74. GRB 030324: Detection and Color of Host Galaxy
  75. GRB 040511: NIR observations with REM
  76. GRB040511: Candidate optical/NIR afterglow
  77. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  78. GRB 040511: Second Epoch Optical Observations
  79. GRB 040511: Optical observations
  80. GRB 040511: Optical Observations
  81. GRB040511: Optical Observations
  82. GRB040511: Optical Observations
  83. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  84. GRB 040423 (=H3175): A Long GRB Localized by HETE
  85. GRB040422 : I-band follow-up observation at Lulin Observatory
  86. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  87. GRB040422, BVRcIc field calibration
  88. GRB 040422,optical observation
  89. GRB 040422: a long GRB detected with INTEGRAL
  90. GRB 040403, deep optical observations
  91. MASTER: HETE Alert 3163, 3167 technical optical observation
  92. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  93. GRB 040403: Optical observations
  94. GRB 040403: a long GRB detected with INTEGRAL
  95. GRB040323: NIR Observations and Variable Object
  96. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  97. GRB 040323, a dark GRB ?
  98. GRB 040323: a long GRB detected with INTEGRAL
  99. GRB040223: Deep NIR NTT data re-analysis
  100. GRB 040223: XMM-Newton results

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