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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"

32717 results found.

  1. XRF 040912, identification of CXO sources
  2. XRF040916, Ic observations
  3. XRF040916: optical follow-up observations
  4. XRF040912, BVRcIc field calibration
  5. XRF040916, BVRcIc field calibration
  6. GRB040916: Archival optical observations
  7. XRF 040916, optical follow-up
  8. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  9. GRB040916: Optical observations
  10. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  11. GRB040916 (= H3558): A Long XRF Localized by HETE
  12. GRB040912 (= H3557): Chandra Observations Scheduled
  13. GRB 040912, BVRI observations
  14. GRB040912 : Kiso Optical follow-up observation
  15. IBAS GRB Alerts 1978-1980
  16. Optical observations of field of GRB040912
  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. Very bright burst detected from SGR 1806-20
  23. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  24. Possible GRB 040903 - further analysis
  25. GRB 040827 - Radio Observations
  26. XMM-Newton Images of GRB 040827
  27. GRB040825A: Optical observations
  28. GRB040825A: Optical observations
  29. GRB 040827: optical and NIR observations at the VLT
  30. GRB 040827: UKIRT - 2nd epoch K-band imaging
  31. GRB 040827: 2nd epoch of Magellan K-band imaging
  32. GRB 040827: K imaging - no evidence of variability
  33. GRB 040827: Detection of NIR afterglow
  34. GRB 040827: Possible detection of optical afterglow
  35. GRB 040827: RTT150 optical observations
  36. MASTER: GRB040827 possible OT
  37. GRB 040825B: Optical observations
  38. GRB040827 optical observations
  39. GRB 040827 - Refined position
  40. GRB040825B, BVRcIc field photometry
  41. GCN GRB OBSERBATION REPORT
  42. GRB040825B: optical observations
  43. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  44. GRB040825B: Correction to GCN 2657
  45. XRF040812: possible afterglow second Chandra observation
  46. GRB 040812: Second epoch CXO Observations
  47. XRF040812: GMRT observations
  48. XRF 040812: optical observation at VLT
  49. GRB 040812: Optical counterparts of CXO sources
  50. XRF040812: possible afterglow
  51. CXO observation of GRB 040812
  52. IPN/HETE localizations of GRB040810 (=H3489)
  53. GRB 040812: Keck and LCO optical observations
  54. GRB 040812: Keck and LCO observations
  55. GRB 040812: radio observations
  56. GRB040812, optical/IR observations
  57. XRF040701: Optical Observations at ESO
  58. IPN/HETE triangulation of GRB040802 (=H3485)
  59. GRB 040730, infrared observations
  60. GRB 040730: Optical observations
  61. Ongoing activity of SGR 1806-20
  62. GRB040624: optical monitoring at TNG
  63. XRF 040701 - optical observations of the decaying Chandra source
  64. XRF040701: Second-Epoch Chandra Observations
  65. XRF040701: VLA Observations
  66. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  67. XRF040701: First-Epoch Chandra Observations
  68. GRB040709 J,H-band observations
  69. GRB040624, optical observations
  70. XRF 040701, optical observations
  71. GRB 040624: optical observations
  72. Optical Observations of GRB040624
  73. GRB 040624: optical observations at TNG and VLT
  74. GRB 040624: R-band observations
  75. GRB 040624, optical observations
  76. GRB 030329: Rebrightening of hyperluminal ejecta.
  77. IPN Summary of SGR1806-20 Activity in 2004
  78. GRB040511: Retraction of redshift identification
  79. SGR 1806-20: no IR variability of the proposed counterparts
  80. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  81. Activivty of SGR 1806-20
  82. GRB 040511, very fast decay?
  83. GRB 030324: Detection and Color of Host Galaxy
  84. GRB 040511: NIR observations with REM
  85. GRB040511: Redshift identifcation
  86. GRB 040511: Optical limit
  87. GRB040511: Candidate optical/NIR afterglow
  88. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  89. GRB 040511: Second Epoch Optical Observations
  90. GRB 040511: Optical observations
  91. GRB 040511: Optical Observations
  92. GRB040511: Optical Observations
  93. GRB040511: Optical Observations
  94. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  95. IPN triangulation of GRB040425 (=H3183)
  96. On Line Availability of Archival HETE Fregate Data and Lightcurves
  97. GRB040422, optical observations at Loiano
  98. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  99. GRB040422, BVRcIc field calibration
  100. GRB040422: optical and NIR observations at the VLT

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