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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"

32721 results found.

  1. TAROT Observations of GRB 040916 (HETE #3558)
  2. GRB040912(=H3557): Candidate Optical Afterglow
  3. XRF040916, optical observations
  4. XRF040916: Optical Transient Candidate by Subaru
  5. XRF 040912, identification of CXO sources
  6. XRF040916, Ic observations
  7. XRF040916: optical follow-up observations
  8. XRF040912, BVRcIc field calibration
  9. XRF040916, BVRcIc field calibration
  10. GRB040916: Archival optical observations
  11. XRF 040916, optical follow-up
  12. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  13. GRB040916: Optical observations
  14. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  15. GRB040916 (= H3558): A Long XRF Localized by HETE
  16. GRB040912 (= H3557): Chandra Observations Scheduled
  17. GRB 040912, BVRI observations
  18. GRB040912 : Kiso Optical follow-up observation
  19. IBAS GRB Alerts 1978-1980
  20. Optical observations of field of GRB040912
  21. GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
  22. GRB040903 - A XRF?
  23. GRB040827: analysis of the XMM-Newton observation
  24. GRB040903, REM near-IR observation
  25. GRB 040903 - INTEGRAL data analysis
  26. Very bright burst detected from SGR 1806-20
  27. ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
  28. Possible GRB 040903 - further analysis
  29. GRB 040827 - Radio Observations
  30. XMM-Newton Images of GRB 040827
  31. GRB040825A: Optical observations
  32. GRB040825A: Optical observations
  33. GRB 040827: optical and NIR observations at the VLT
  34. GRB 040827: UKIRT - 2nd epoch K-band imaging
  35. GRB 040827: 2nd epoch of Magellan K-band imaging
  36. GRB 040827: K imaging - no evidence of variability
  37. GRB 040827: Detection of NIR afterglow
  38. GRB 040827: Possible detection of optical afterglow
  39. GRB 040827: RTT150 optical observations
  40. MASTER: GRB040827 possible OT
  41. GRB 040825B: Optical observations
  42. GRB040827 optical observations
  43. GRB 040827 - Refined position
  44. GRB040825B, BVRcIc field photometry
  45. GCN GRB OBSERBATION REPORT
  46. GRB040825B: optical observations
  47. GRB040825B (=H3510): An XRF Localized in Real Time by HETE
  48. GRB040825B: Correction to GCN 2657
  49. XRF040812: possible afterglow second Chandra observation
  50. GRB 040812: Second epoch CXO Observations
  51. XRF040812: GMRT observations
  52. XRF 040812: optical observation at VLT
  53. GRB 040812: Optical counterparts of CXO sources
  54. XRF040812: possible afterglow
  55. CXO observation of GRB 040812
  56. IPN/HETE localizations of GRB040810 (=H3489)
  57. GRB 040812: Keck and LCO optical observations
  58. GRB 040812: Keck and LCO observations
  59. GRB 040812: radio observations
  60. GRB040812, optical/IR observations
  61. XRF040701: Optical Observations at ESO
  62. IPN/HETE triangulation of GRB040802 (=H3485)
  63. GRB 040730, infrared observations
  64. GRB 040730: Optical observations
  65. Ongoing activity of SGR 1806-20
  66. GRB040624: optical monitoring at TNG
  67. XRF 040701 - optical observations of the decaying Chandra source
  68. XRF040701: Second-Epoch Chandra Observations
  69. XRF040701: VLA Observations
  70. XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
  71. XRF040701: First-Epoch Chandra Observations
  72. GRB040709 J,H-band observations
  73. GRB040624, optical observations
  74. XRF 040701, optical observations
  75. GRB 040624: optical observations
  76. Optical Observations of GRB040624
  77. GRB 040624: optical observations at TNG and VLT
  78. GRB 040624: R-band observations
  79. GRB 040624, optical observations
  80. GRB 030329: Rebrightening of hyperluminal ejecta.
  81. IPN Summary of SGR1806-20 Activity in 2004
  82. GRB040511: Retraction of redshift identification
  83. SGR 1806-20: no IR variability of the proposed counterparts
  84. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  85. Activivty of SGR 1806-20
  86. GRB 040511, very fast decay?
  87. GRB 030324: Detection and Color of Host Galaxy
  88. GRB 040511: NIR observations with REM
  89. GRB040511: Redshift identifcation
  90. GRB 040511: Optical limit
  91. GRB040511: Candidate optical/NIR afterglow
  92. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  93. GRB 040511: Second Epoch Optical Observations
  94. GRB 040511: Optical observations
  95. GRB 040511: Optical Observations
  96. GRB040511: Optical Observations
  97. GRB040511: Optical Observations
  98. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  99. IPN triangulation of GRB040425 (=H3183)
  100. On Line Availability of Archival HETE Fregate Data and Lightcurves

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